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Shiotani K, Tanisumi Y, Osako Y, Murata K, Hirokawa J, Sakurai Y, Manabe H. An intra-oral flavor detection task in freely moving mice. iScience 2024; 27:108924. [PMID: 38327778 PMCID: PMC10847684 DOI: 10.1016/j.isci.2024.108924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 12/05/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
Flavor plays a critical role in the pleasure of food. Flavor research has mainly focused on human subjects and revealed that many brain regions are involved in flavor perception. However, animal models for elucidating the mechanisms of neural circuits are lacking. Herein, we demonstrate the use of a novel behavioral task in which mice are capable of flavor detection. When the olfactory pathways of the mice were blocked, they could not perform the task. However, behavioral accuracy was not affected when the gustatory pathway was blocked by benzocaine. These results indicate that the mice performed this detection task mainly based on the olfaction. We conclude that this novel task can contribute to research on the neural mechanisms of flavor perception.
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Affiliation(s)
- Kazuki Shiotani
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Laboratory of Brain Network Information, College of Life Sciences, Ritsumeikan University, Shiga, Japan
| | - Yuta Tanisumi
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Department of Anatomy and Molecular Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Division of Multicellular Circuit Dynamics, National Institute for Physiological Sciences, National Institute of Natural Sciences, Nagoya, Japan
- Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan
| | - Yuma Osako
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, United States
| | - Koshi Murata
- Division of Brain Structure and Function, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Junya Hirokawa
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Department of Functional Brain Imaging, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Yoshio Sakurai
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
| | - Hiroyuki Manabe
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, Kyoto, Japan
- Department of Neurophysiology, Nara Medical University, Nara, Japan
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2
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Dera AM, Shen T, Thackray AE, Hinton EC, King JA, James L, Morgan PS, Rush N, Miyashita M, Batterham RL, Stensel DJ. The influence of physical activity on neural responses to visual food cues in humans: A systematic review of functional magnetic resonance imaging studies. Neurosci Biobehav Rev 2023; 152:105247. [PMID: 37236384 DOI: 10.1016/j.neubiorev.2023.105247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 05/28/2023]
Abstract
This systematic review examined whether neural responses to visual food-cues measured by functional magnetic resonance imaging (fMRI) are influenced by physical activity. Seven databases were searched up to February 2023 for human studies evaluating visual food-cue reactivity using fMRI alongside an assessment of habitual physical activity or structured exercise exposure. Eight studies (1 exercise training, 4 acute crossover, 3 cross-sectional) were included in a qualitative synthesis. Structured acute and chronic exercise appear to lower food-cue reactivity in several brain regions, including the insula, hippocampus, orbitofrontal cortex (OFC), postcentral gyrus and putamen, particularly when viewing high-energy-density food cues. Exercise, at least acutely, may enhance appeal of low-energy-density food-cues. Cross-sectional studies show higher self-reported physical activity is associated with lower reactivity to food-cues particularly of high-energy-density in the insula, OFC, postcentral gyrus and precuneus. This review shows that physical activity may influence brain food-cue reactivity in motivational, emotional, and reward-related processing regions, possibly indicative of a hedonic appetite-suppressing effect. Conclusions should be drawn cautiously given considerable methodological variability exists across limited evidence.
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Affiliation(s)
- Abdulrahman M Dera
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; College of Sport Sciences, Jeddah University, Saudi Arabia; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK
| | - Tonghui Shen
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK
| | - Alice E Thackray
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK
| | - Elanor C Hinton
- National Institute for Health and Care Research (NIHR) Bristol Biomedical Centre Diet and Physical Activity Theme, University of Bristol, UK; Oxford Medical Products Limited, Witney Business and Innovation Centre, Witney, UK
| | - James A King
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK
| | - Lewis James
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK
| | - Paul S Morgan
- Radiological Sciences, School of Medicine, University of Nottingham, UK; National Institute for Health and Care Research (NIHR) Nottingham Biomedical Research Centre, Nottingham, UK
| | - Nathan Rush
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK
| | - Masashi Miyashita
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan; Department of Sports Science and Physical Education, The Chinese University of Hong Kong, Hong Kong
| | - Rachel L Batterham
- Department of Medicine, Centre for Obesity Research, University College London, UK; National Institute for Health and Care Research, University College London Hospitals Biomedical Research Centre, London, UK
| | - David J Stensel
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, UK; National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and University of Leicester, UK; Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan; Department of Sports Science and Physical Education, The Chinese University of Hong Kong, Hong Kong.
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3
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Avery JA, Carrington M, Martin A. A common neural code for representing imagined and inferred tastes. Prog Neurobiol 2023; 223:102423. [PMID: 36805499 PMCID: PMC10040442 DOI: 10.1016/j.pneurobio.2023.102423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/11/2023] [Accepted: 02/15/2023] [Indexed: 02/18/2023]
Abstract
Inferences about the taste of foods are a key aspect of our everyday experience of food choice. Despite this, gustatory mental imagery is a relatively under-studied aspect of our mental lives. In the present study, we examined subjects during high-field fMRI as they actively imagined basic tastes and subsequently viewed pictures of foods dominant in those specific taste qualities. Imagined tastes elicited activity in the bilateral dorsal mid-insula, one of the primary cortical regions responsive to the experience of taste. In addition, within this region we reliably decoded imagined tastes according to their dominant quality - sweet, sour, or salty - thus indicating that, like actual taste, imagined taste activates distinct quality-specific neural patterns. Using a cross-task decoding analysis, we found that the neural patterns for imagined tastes and food pictures in the mid-insula were reliably similar and quality-specific, suggesting a common code for representing taste quality regardless of whether explicitly imagined or automatically inferred when viewing food. These findings have important implications for our understanding of the mechanisms of mental imagery and the multimodal nature of presumably primary sensory brain regions like the dorsal mid-insula.
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Affiliation(s)
- Jason A Avery
- Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20892, United States.
| | - Madeline Carrington
- Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20892, United States
| | - Alex Martin
- Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20892, United States
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4
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Edwin Thanarajah S, DiFeliceantonio AG, Albus K, Kuzmanovic B, Rigoux L, Iglesias S, Hanßen R, Schlamann M, Cornely OA, Brüning JC, Tittgemeyer M, Small DM. Habitual daily intake of a sweet and fatty snack modulates reward processing in humans. Cell Metab 2023; 35:571-584.e6. [PMID: 36958330 DOI: 10.1016/j.cmet.2023.02.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/21/2022] [Accepted: 02/23/2023] [Indexed: 03/25/2023]
Abstract
Western diets rich in fat and sugar promote excess calorie intake and weight gain; however, the underlying mechanisms are unclear. Despite a well-documented association between obesity and altered brain dopamine function, it remains elusive whether these alterations are (1) pre-existing, increasing the individual susceptibility to weight gain, (2) secondary to obesity, or (3) directly attributable to repeated exposure to western diet. To close this gap, we performed a randomized, controlled study (NCT05574660) with normal-weight participants exposed to a high-fat/high-sugar snack or a low-fat/low-sugar snack for 8 weeks in addition to their regular diet. The high-fat/high-sugar intervention decreased the preference for low-fat food while increasing brain response to food and associative learning independent of food cues or reward. These alterations were independent of changes in body weight and metabolic parameters, indicating a direct effect of high-fat, high-sugar foods on neurobehavioral adaptations that may increase the risk for overeating and weight gain.
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Affiliation(s)
- Sharmili Edwin Thanarajah
- Max Planck Institute for Metabolism Research, Cologne, Germany; Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe University, Frankfurt, Germany
| | - Alexandra G DiFeliceantonio
- Fralin Biomedical Research Institute at Virginia Tech Carilion & Department of Human Nutrition, Foods, and Exercise, College of Agriculture and Life Sciences, Roanoke, VA, USA
| | - Kerstin Albus
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD) & Excellence Center for Medical Mycology (ECMM), Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | | | - Lionel Rigoux
- Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Sandra Iglesias
- Translational Neuromodeling Unit, Institute for Biomedical Engineering, University of Zurich and Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Ruth Hanßen
- Max Planck Institute for Metabolism Research, Cologne, Germany; Policlinic for Endocrinology, Diabetes and Preventive Medicine (PEPD), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Marc Schlamann
- Department of Neuroradiology, University Hospital of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Oliver A Cornely
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD) & Excellence Center for Medical Mycology (ECMM), Faculty of Medicine and University Hospital Cologne, Cologne, Germany; German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, Cologne, Germany; Clinical Trials Centre Cologne (ZKS Köln), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Policlinic for Endocrinology, Diabetes and Preventive Medicine (PEPD), University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Marc Tittgemeyer
- Max Planck Institute for Metabolism Research, Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
| | - Dana M Small
- Modern Diet and Physiology Research Center, New Haven, CT, USA; Yale University School of Medicine, Department of Psychiatry, New Haven, CT, USA.
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Zhang X, Wen K, Han J, Chen H. The Neural Processes in Food Decision-making and their Effect on Daily Diet Management in Successful and Unsuccessful Restrained Eaters. Neuroscience 2023; 517:1-17. [PMID: 36764599 DOI: 10.1016/j.neuroscience.2023.01.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/08/2023] [Accepted: 01/20/2023] [Indexed: 02/11/2023]
Abstract
This study aimed to explore the neural mechanisms underlying food decision making in unsuccessful restrained eaters (US-REs) and successful restrained eaters (S-REs). During a functional magnetic resonance imaging scan, participants were required to choose between pairs of high- and low-calorie foods under the following conditions: the congruent condition (choose between high- and low-calorie foods with the same level of tastiness) and incongruent condition (choose between high-calorie foods tastier than the corresponding low-calorie foods). Subsequently, the participants' diets were monitored for one week. The behavioral results showed that US-REs (n = 28) chose more high-calorie foods than S-REs (n = 26); in contrast, S-REs spent more time in choosing for the incongruent than the congruent condition. The fMRI results found that US-REs exhibited more activity in reward regions (caudate and thalamus) than S-REs in the congruent condition. In the incongruent condition, S-REs showed stronger functional connectivity between the conflict-monitoring region (anterior cingulate cortex) and inhibitory-control regions (inferior frontal gyrus [IFG] and medial frontal gyrus) than US-REs. In both the conditions, increased activation of the insula, putamen, middle frontal gyrus, and IFG could predict increased food intake among US-REs in the following week. Furthermore, in both the conditions, increased IFG activation could predict decreased food cravings among S-REs during the following week. Our results suggest that US-REs have a strong reward response to food. Compared to US-REs, S-REs are more guided more by the goal of weight control, and exhibit strong functional connections between the conflict-monitoring and inhibitory-control regions. Therefore, eating enjoyment and weight-control goals influence restrained eating in daily life.
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Affiliation(s)
- Xuemeng Zhang
- School of Psychology, Southwest University, Chongqing, China; Research Center for Brain and Cognitive Science, Chongqing Normal University, Chongqing, China
| | - Ke Wen
- Research Center for Brain and Cognitive Science, Chongqing Normal University, Chongqing, China
| | - Jinfeng Han
- School of Psychology, Southwest University, Chongqing, China
| | - Hong Chen
- School of Psychology, Southwest University, Chongqing, China.
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6
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Rolls ET. The orbitofrontal cortex, food reward, body weight and obesity. Soc Cogn Affect Neurosci 2023; 18:nsab044. [PMID: 33830272 PMCID: PMC9997078 DOI: 10.1093/scan/nsab044] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/17/2021] [Accepted: 04/08/2021] [Indexed: 12/23/2022] Open
Abstract
In primates including humans, the orbitofrontal cortex is the key brain region representing the reward value and subjective pleasantness of the sight, smell, taste and texture of food. At stages of processing before this, in the insular taste cortex and inferior temporal visual cortex, the identity of the food is represented, but not its affective value. In rodents, the whole organisation of reward systems appears to be different, with reward value reflected earlier in processing systems. In primates and humans, the amygdala is overshadowed by the great development of the orbitofrontal cortex. Social and cognitive factors exert a top-down influence on the orbitofrontal cortex, to modulate the reward value of food that is represented in the orbitofrontal cortex. Recent evidence shows that even in the resting state, with no food present as a stimulus, the liking for food, and probably as a consequence of that body mass index, is correlated with the functional connectivity of the orbitofrontal cortex and ventromedial prefrontal cortex. This suggests that individual differences in these orbitofrontal cortex reward systems contribute to individual differences in food pleasantness and obesity. Implications of how these reward systems in the brain operate for understanding, preventing and treating obesity are described.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, UK
- Department of Computer Science, University of Warwick, Coventry, UK
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7
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Mulheren R, Westemeyer RM, Dietsch AM. The effect of taste on swallowing: A scoping and systematic review. Crit Rev Food Sci Nutr 2022; 64:1256-1282. [PMID: 36036968 DOI: 10.1080/10408398.2022.2115003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Consuming foods and liquids for nutrition requires the coordination of several muscles. Swallowing is triggered and modified by sensory inputs from the aerodigestive tract. Taste has recently received attention as a potential modulator of swallowing physiology, function, and neural activation; additionally, taste impairment is a sequela of COVID-19. This review presents factors impacting taste and swallowing, systematically summarizes the existing literature, and assesses the quality of included studies. A search was conducted for original research including taste stimulation, deglutition-related measure(s), and human participants. Study design, independent and dependent variables, and participant characteristics were coded; included studies were assessed for quality and risk of bias. Forty-eight articles were included after abstract and full-text review. Synthesis was complicated by variable sensory components of stimuli (taste category and intensity, pure taste vs. flavor, chemesthesis, volume/amount, consistency, temperature), participant characteristics, confounding variables such as genetic taster status, and methods of measurement. Most studies had a high risk of at least one type of bias and were of fair or poor quality. Interpretation is limited by wide variability in methods, taste stimulation, confounding factors, and lower-quality evidence. Existing studies suggest that taste can modulate swallowing, but more rigorous and standardized research is needed.
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Affiliation(s)
- Rachel Mulheren
- Department of Psychological Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ross M Westemeyer
- Department of Special Education and Communication Disorders, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Angela M Dietsch
- Department of Special Education and Communication Disorders, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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Parsons N, Steward T, Clohesy R, Almgren H, Duehlmeyer L. A systematic review of resting-state functional connectivity in obesity: Refining current neurobiological frameworks and methodological considerations moving forward. Rev Endocr Metab Disord 2022; 23:861-879. [PMID: 34159504 DOI: 10.1007/s11154-021-09665-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/09/2021] [Indexed: 02/07/2023]
Abstract
Obesity is the second most common cause of preventable morbidity worldwide. Resting-state functional magnetic resonance imaging (fMRI) has been used extensively to characterise altered communication between brain regions in individuals with obesity, though findings from this research have not yet been systematically evaluated within the context of prominent neurobiological frameworks. This systematic review aggregated resting-state fMRI findings in individuals with obesity and evaluated the contribution of these findings to current neurobiological models. Findings were considered in relation to a triadic model of problematic eating, outlining disrupted communication between reward, inhibitory, and homeostatic systems. We identified a pattern of consistently increased orbitofrontal and decreased insula cortex resting-state functional connectivity in individuals with obesity in comparison to healthy weight controls. BOLD signal amplitude was also increased in people with obesity across studies, predominantly confined to subcortical regions, including the hippocampus, amygdala, and putamen. We posit that altered orbitofrontal cortex connectivity may be indicative of a shift in the valuation of food-based rewards and that dysfunctional insula connectivity likely contributes to altered homeostatic signal processing. Homeostatic violation signals in obesity may be maintained despite satiety, thereby 'hijacking' the executive system and promoting further food intake. Moving forward, we provide a roadmap for more reliable resting-state and task-based functional connectivity experiments, which must be reconciled within a common framework if we are to uncover the interplay between psychological and biological factors within current theoretical frameworks.
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Affiliation(s)
- Nicholas Parsons
- Cognitive Neuroscience Unit, School of Psychology, Deakin University, Melbourne Burwood Campus, VIC, Australia
| | - Trevor Steward
- Melbourne School of Psychological Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Rebecca Clohesy
- School of Psychology, Deakin University, Melbourne Burwood Campus, VIC, Australia
| | - Hannes Almgren
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Department of Data Analysis, Faculty of Psychology and Educational Sciences, Ghent University, Ghent, Belgium
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Oren S, Tittgemeyer M, Rigoux L, Schlamann M, Schonberg T, Kuzmanovic B. Neural Encoding of Food and Monetary Reward Delivery. Neuroimage 2022; 257:119335. [PMID: 35643268 DOI: 10.1016/j.neuroimage.2022.119335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 11/18/2022] Open
Abstract
Different types of rewards such as food and money can similarly drive our behavior owing to shared brain processes encoding their subjective value. However, while the value of money is abstract and needs to be learned, the value of food is rooted in the innate processing of sensory properties and nutritional utilization. Yet, the actual consumption of food and the receipt of money have never been directly contrasted in the same experiment, questioning what unique neural processes differentiate those reward types. To fill this gap, we examined the distinct and common neural responses to the delivery of food and monetary rewards during fMRI. In a novel experimental approach, we parametrically manipulated the subjective value of food and monetary rewards by modulating the quantities of administered palatable milkshake and monetary gains. The receipt of increasing amounts of milkshake and money recruited the ventral striatum and the ventromedial prefrontal cortex, previously associated with value encoding. Notably, the consumption and the subsequent evaluation of increasing quantities of milkshake relative to money revealed an extended recruitment of brain regions related to taste, somatosensory processing, and salience. Moreover, we detected a decline of reward encoding in the ventral tegmental area, nucleus accumbens, and vmPFC, indicating that these regions may be susceptible to time-dependent effects upon accumulation of food and money rewards. Relative to monetary gains, the consumption and evaluation of palatable milkshakes engaged complex neural processing over and above value tracking, emphasizing the critical contribution of taste and other sensory properties to the processing of food rewards. Furthermore, our results highlight the need to closely monitor metabolic states and neural responses to the accumulation of rewards to pinpoint the mechanisms underlying time-dependent dynamics of reward-related processing.
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Affiliation(s)
- Shiran Oren
- Sagol School of Neuroscience, Tel Aviv University, P.O. Box 39040, Tel Aviv 6997801, Israel; Translational Neurocircuitry Group, Max Planck Institute for Metabolism Research, Gleuelerstr. 50, Cologne 50931, Germany
| | - Marc Tittgemeyer
- Translational Neurocircuitry Group, Max Planck Institute for Metabolism Research, Gleuelerstr. 50, Cologne 50931, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, Cologne 50931, Germany
| | - Lionel Rigoux
- Translational Neurocircuitry Group, Max Planck Institute for Metabolism Research, Gleuelerstr. 50, Cologne 50931, Germany
| | - Marc Schlamann
- Institute for Diagnostic and Interventional Radiology, University Hospital Cologne, Kerpenerstr. 62, Cologne 50937, Germany
| | - Tom Schonberg
- Sagol School of Neuroscience, Tel Aviv University, P.O. Box 39040, Tel Aviv 6997801, Israel; Department of Neurobiology, The George S. Wise Faculty of Life Sciences, P.O. Box 39040, Tel Aviv 6997801, Israel
| | - Bojana Kuzmanovic
- Translational Neurocircuitry Group, Max Planck Institute for Metabolism Research, Gleuelerstr. 50, Cologne 50931, Germany.
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Althubeati S, Avery A, Tench CR, Lobo DN, Salter A, Eldeghaidy S. Mapping brain activity of gut-brain signaling to appetite and satiety in healthy adults: A systematic review and functional neuroimaging meta-analysis. Neurosci Biobehav Rev 2022; 136:104603. [PMID: 35276299 PMCID: PMC9096878 DOI: 10.1016/j.neubiorev.2022.104603] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 02/20/2022] [Accepted: 03/06/2022] [Indexed: 12/19/2022]
Abstract
Understanding how neurohormonal gut-brain signaling regulates appetite and satiety is vital for the development of therapies for obesity and altered eating behavior. However, reported brain areas associated with appetite or satiety regulators show inconsistency across functional neuroimaging studies. The aim of this study was to systematically assess the convergence of brain regions modulated by appetite and satiety regulators. Twenty-five studies were considered for qualitative synthesis, and 14 independent studies (20-experiments) found eligible for coordinate-based neuroimaging meta-analyses across 212 participants and 123 foci. We employed two different meta-analysis approaches. The results from the systematic review revealed the modulation of insula, amygdala, hippocampus, and orbitofrontal cortex (OFC) with appetite regulators, where satiety regulators were more associated with caudate nucleus, hypothalamus, thalamus, putamen, anterior cingulate cortex in addition to the insula and OFC. The two neuroimaging meta-analyses methods identified the caudate nucleus as a key area associated with satiety regulators. Our results provide quantitative brain activation maps of neurohormonal gut-brain signaling in heathy-weight adults that can be used to define alterations with eating behavior.
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Affiliation(s)
- Sarah Althubeati
- Division of Food, Nutrition & Dietetics, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK; Faculty of Applied Medical Sciences, Department of Clinical Nutrition, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Amanda Avery
- Division of Food, Nutrition & Dietetics, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK
| | - Christopher R Tench
- Division of Clinical Neurosciences, Clinical Neurology, University of Nottingham, Queen's Medical Centre, Nottingham, UK; NIHR Nottingham Biomedical Research Centre, Queen's Medical Centre, University of Nottingham, Nottingham, UK
| | - Dileep N Lobo
- Nottingham Digestive Diseases Centre, National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK; MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Andrew Salter
- Division of Food, Nutrition & Dietetics and Future Food Beacon, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK
| | - Sally Eldeghaidy
- Division of Food, Nutrition & Dietetics and Future Food Beacon, School of Biosciences, University of Nottingham, Loughborough LE12 5RD, UK; Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK.
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12
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Iceta S, Panahi S, García-García I, Michaud A. The Impact of Restrictive and Non-restrictive Dietary Weight Loss Interventions on Neurobehavioral Factors Related to Body Weight Control: the Gaps and Challenges. Curr Obes Rep 2021; 10:385-395. [PMID: 34318394 DOI: 10.1007/s13679-021-00452-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/03/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE OF REVIEW Restrictive diets, such as low-calorie diets, are difficult to maintain in the long term. For this reason, their popularity has decreased compared to non-restrictive approaches, which instead promote healthy eating strategies. Since both strategies may entail different neurobiological mechanisms, this review will examine the current evidence on the effects of restrictive and non-restrictive interventions on neurobehavioral factors. RECENT FINDINGS Restrictive diets appear to improve eating behaviors, and the evidence reviewed argues against the notion that they may worsen the severity of binge eating. Moreover, they may lead to short-term changes in brain structure and improvements in cerebrovascular markers which, in turn, could impact eating behaviors. Non-restrictive interventions may have a positive effect on weight management and eating behaviors. However, evidence of their neural effects is scarce. Small sample sizes, short follow-ups, and the absence of control groups are limitations of the studies targeting both interventions. Rigorous long-term randomized studies are needed to examine the neurobehavioral effects of restrictive and non-restrictive approaches.
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Affiliation(s)
- Sylvain Iceta
- Quebec Heart and Lung Institute Research Center, Québec, QC, G1V 4G5, Canada
- Centre Nutrition, Santé et Société (NUTRISS), Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Québec, QC, G1V OA6, Canada
- School of Nutrition, Université Laval, Québec, QC, G1V OA6, Canada
| | - Shirin Panahi
- Centre Nutrition, Santé et Société (NUTRISS), Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Québec, QC, G1V OA6, Canada
- Faculty of Educational Sciences, Department of Physical Education, Université Laval, Québec, QC, G1V OA6, Canada
- Faculty of Medicine, Department of Kinesiology, Université Laval, Québec, QC, G1V OA6, Canada
| | - Isabel García-García
- Department of Clinical Psychology and Psychobiology, University of Barcelona, 08035, Barcelona, Spain
| | - Andréanne Michaud
- Quebec Heart and Lung Institute Research Center, Québec, QC, G1V 4G5, Canada.
- Centre Nutrition, Santé et Société (NUTRISS), Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Québec, QC, G1V OA6, Canada.
- School of Nutrition, Université Laval, Québec, QC, G1V OA6, Canada.
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13
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Hébert-Seropian B, Boucher O, Jutras-Aswad D, Nguyen DK. Uncommon case of complete loss of hunger following an isolated left insular stroke. Neurocase 2021; 27:349-353. [PMID: 34397317 DOI: 10.1080/13554794.2021.1966044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The insula has long been among the least understood regions of the human brain, in part due to its restricted accessibility. Mounting evidence suggests that the insula is a prominent player in gustatory, interoceptive, and emotional processing, and likely integrates these different functions to contribute to the homeostatic control of food intake. Here we report the case of a young adult patient who lost the subjective experience of hunger following an ischemic stroke localized in the posterior left insula. The loss of hunger was not attributable to medication, substance use, or a clinical disorder, and lasted for a period of 15 months. In line with the role attributed to the insula in gustation and interoception, we suggest that the insula integrates information about taste, interoception, and the hedonic value of food in the service of homeostatic regulation.
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Affiliation(s)
- Benjamin Hébert-Seropian
- Département de psychologie, Université du Québec à Montréal, Montreal, Quebec, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Olivier Boucher
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.,Département de psychologie, Université de Montréal, Montreal, Quebec, Canada.,Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, Canada
| | - Didier Jutras-Aswad
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.,Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, Canada.,Département de psychiatrie et addictologie, Université de Montréal, Montreal, Quebec, Canada
| | - Dang Khoa Nguyen
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.,Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, Canada.,Département de neurosciences, Université de Montréal, Montreal, Quebec, Canada
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14
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Hébert-Seropian B, Boucher O, Citherlet D, Roy-Côté F, Gravel V, Obaid S, Bouthillier A, Nguyen DK. Decreased self-reported appetite following insular cortex resection in patients with epilepsy. Appetite 2021; 166:105479. [PMID: 34186157 DOI: 10.1016/j.appet.2021.105479] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 01/10/2023]
Abstract
Entrenched deep within the Sylvian fissure, the insula has long been considered one of the least understood regions of the human brain, in part due to its restricted accessibility. However, recent evidence suggests that the insula plays a key role in gustation, interoception, cognitive and emotional processes, and likely integrates these different functions to contribute to the homeostatic control of food intake. In the past decade, our team has identified the insula as a potential site of epileptogenicity, which can be successfully treated by microsurgical resection. While most surgeries are successful in controlling insular epileptic seizures and lead to few postoperative deficits, the subtle changes that may occur in food-related experiences are still unknown. Using a self-report questionnaire, the present study sought to fill this gap by assessing changes in appetite in patients who underwent unilateral partial or complete insular resections (n = 17) as part of their epilepsy surgery. We compared them to a group of patients who underwent temporal lobe epilepsy surgery (n = 22) as a lesion-control group. A majority (59%) of the insular patients reported an alteration in appetite, with most of these changes being characterized by a persistent reduction. Such changes were rarely reported following temporal lobectomy (14%). While they significantly differed in terms of appetite changes, both groups were similar when examining post-surgical changes in weight, diet, exercise and eating habits. Insular patients with altered appetite also showed behavioral signs of dysfunctional interoceptive and gustatory functions, corroborating the idea that these systems play a role in the regulation of feeding behaviours. This research pushes our understanding of the mechanisms underlying food intake and could lead to avenues for the treatment of eating disorders.
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Affiliation(s)
- Benjamin Hébert-Seropian
- Département de psychologie, Université du Québec à Montréal, Montreal, QC, Canada; Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Olivier Boucher
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Département de psychologie, Université de Montréal, Montreal, QC, Canada; Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Daphné Citherlet
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Département de neurosciences, Université de Montréal, Montreal, QC, Canada
| | - Frédérique Roy-Côté
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Département de psychologie, Université de Montréal, Montreal, QC, Canada
| | - Victoria Gravel
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Département de psychologie, Université de Montréal, Montreal, QC, Canada
| | - Sami Obaid
- Division de neurochirurgie, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada; Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Alain Bouthillier
- Division de neurochirurgie, Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada; Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Dang Khoa Nguyen
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada; Département de neurosciences, Université de Montréal, Montreal, QC, Canada; Centre Hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada.
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15
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Avery JA. Against gustotopic representation in the human brain: There is no Cartesian Restaurant. CURRENT OPINION IN PHYSIOLOGY 2021; 20:23-28. [PMID: 33521413 PMCID: PMC7839947 DOI: 10.1016/j.cophys.2021.01.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The insular cortex is still one of the least understood cortical regions in the human brain. This review will highlight research on taste quality representation within the human insular cortex. Much of the controversy surrounding this topic is based in the ongoing debate over different theories of peripheral taste coding. When translated to the study of gustatory cortex, this has generated a distinct set of theoretical models, namely the topographic (or 'gustotopic') and population coding models of taste organization. Recent investigations into this topic have employed high-resolution functional neuroimaging methods and multivariate analytic approaches to examine taste quality coding in the human brain. Collectively, these recent studies do not support the topographic model of taste quality representation, but rather one where taste quality is represented by distributed patterns of activation within gustatory regions of the insula.
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Affiliation(s)
- Jason A Avery
- Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD, United States, 20892
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16
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Gautron L. The Phantom Satiation Hypothesis of Bariatric Surgery. Front Neurosci 2021; 15:626085. [PMID: 33597843 PMCID: PMC7882491 DOI: 10.3389/fnins.2021.626085] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 01/06/2021] [Indexed: 01/26/2023] Open
Abstract
The excitation of vagal mechanoreceptors located in the stomach wall directly contributes to satiation. Thus, a loss of gastric innervation would normally be expected to result in abrogated satiation, hyperphagia, and unwanted weight gain. While Roux-en-Y-gastric bypass (RYGB) inevitably results in gastric denervation, paradoxically, bypassed subjects continue to experience satiation. Inspired by the literature in neurology on phantom limbs, I propose a new hypothesis in which damage to the stomach innervation during RYGB, including its vagal supply, leads to large-scale maladaptive changes in viscerosensory nerves and connected brain circuits. As a result, satiation may continue to arise, sometimes at exaggerated levels, even in subjects with a denervated or truncated stomach. The same maladaptive changes may also contribute to dysautonomia, unexplained pain, and new emotional responses to eating. I further revisit the metabolic benefits of bariatric surgery, with an emphasis on RYGB, in the light of this phantom satiation hypothesis.
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Affiliation(s)
- Laurent Gautron
- Department of Internal Medicine, Center for Hypothalamic Research, The University of Texas Southwestern Medical Center, Dallas, TX, United States
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17
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Sun W, Kober H. Regulating food craving: From mechanisms to interventions. Physiol Behav 2020; 222:112878. [PMID: 32298667 PMCID: PMC7321886 DOI: 10.1016/j.physbeh.2020.112878] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/25/2020] [Accepted: 03/15/2020] [Indexed: 01/01/2023]
Abstract
Craving, defined here as a strong desire to eat, is a common experience that drives behavior. Here we discuss the concept of craving from historical, physiological, and clinical perspectives, and review work investigating the effects of cue reactivity and cue-induced craving on eating and weight outcomes, as well as underlying neural mechanisms. We also highlight the significance of cue reactivity and craving in the context of our "toxic food environment" and the obesity epidemic. We then summarize our work developing the Regulation of Craving (ROC) task, used to test the causal effects of cognitive strategies on craving for food and drugs as well as the underlying neural mechanisms of such regulation. Next, we review our recent development of a novel ROC-based intervention that trains individuals to use cognitive strategies to regulate craving, with promising effects on subsequent food choice and caloric consumption. We end by discussing future directions for this important line of work.
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Affiliation(s)
- Wendy Sun
- Yale University, New Haven, CT 06510, United States; Harvard University, Boston, MA 02115, United States
| | - Hedy Kober
- Yale University, New Haven, CT 06510, United States.
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18
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Baldwin MW, Ko MC. Functional evolution of vertebrate sensory receptors. Horm Behav 2020; 124:104771. [PMID: 32437717 DOI: 10.1016/j.yhbeh.2020.104771] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 04/20/2020] [Accepted: 04/28/2020] [Indexed: 12/15/2022]
Abstract
Sensory receptors enable animals to perceive their external world, and functional properties of receptors evolve to detect the specific cues relevant for an organism's survival. Changes in sensory receptor function or tuning can directly impact an organism's behavior. Functional tests of receptors from multiple species and the generation of chimeric receptors between orthologs with different properties allow for the dissection of the molecular basis of receptor function and identification of the key residues that impart functional changes in different species. Knowledge of these functionally important sites facilitates investigation into questions regarding the role of epistasis and the extent of convergence, as well as the timing of sensory shifts relative to other phenotypic changes. However, as receptors can also play roles in non-sensory tissues, and receptor responses can be modulated by numerous other factors including varying expression levels, alternative splicing, and morphological features of the sensory cell, behavioral validation can be instrumental in confirming that responses observed in heterologous systems play a sensory role. Expression profiling of sensory cells and comparative genomics approaches can shed light on cell-type specific modifications and identify other proteins that may affect receptor function and can provide insight into the correlated evolution of complex suites of traits. Here we review the evolutionary history and diversity of functional responses of the major classes of sensory receptors in vertebrates, including opsins, chemosensory receptors, and ion channels involved in temperature-sensing, mechanosensation and electroreception.
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Affiliation(s)
| | - Meng-Ching Ko
- Max Planck Institute for Ornithology, Seewiesen, Germany
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19
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Yu DD, You LZ, Huang WQ, Cao H, Wang FJ, Tang XQ, Fang ZH, Shen GM, Guan YX. Effects of traditional Chinese exercises on blood glucose and hemoglobin A1c levels in patients with prediabetes: A systematic review and meta-analysis. JOURNAL OF INTEGRATIVE MEDICINE 2020; 18:292-302. [PMID: 32534937 DOI: 10.1016/j.joim.2020.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 01/06/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Traditional Chinese exercises (TCEs) have a positive effect on glycemic control and hemoglobin A1c (HbA1c), but there is no consensus on the benefits of TCEs for patients with prediabetes. OBJECTIVE The objective of this study was to systematically investigate the effects of TCEs on blood glucose control in patients with prediabetes. SEARCH STRATEGY Comprehensive retrieval of randomized controlled trials (RCTs) was carried out using PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals, Wanfang Data Knowledge Service Platform, China Biology Medicine disc, Google Scholar and Baidu academic databases. The retrieval window ranged from the establishment of the database to December 2018, and references related to the included trials were searched without language restrictions. INCLUSION CRITERIA The study included RCTs with a clinical diagnosis of prediabetes that was also treated with TCEs. DATA EXTRACTION AND ANALYSIS Literature screening, data extraction and literature quality assessment were performed independently by two researchers. In the case of disagreement, a third party was invited to negotiate and make a decision. Standardized mean difference (SMD) was used to estimate the therapeutic effect. Meta-analysis was performed using Review Manager 5.3.5 and Stata 15.0. Heterogeneity was assessed using Q test and I2, and the source of heterogeneity was determined using Galbraith diagram and sensitivity analysis. A Q test resulting in P < 0.1 and I2 > 50% indicated significant difference and random effect model analysis was performed. Otherwise, a fixed effect model was applied. Begg's and Egger's tests were used to assess publication bias. RESULTS Nine RCTs involving 485 participants were included in this study. The results showed that TCEs could reduce fasting blood glucose (FBG), 2 h blood glucose (2hPBG) and HbA1c in patients with prediabetes. The treatment subgroup showed that an intervention of 6 months had better results, while the Gongfa subgroup showed that the TCE Baduanjin yielded better results. (1) FBG: SMD = -0.73, 95% confidence interval (CI) [-0.97, -0.50], P < 0.00001; Baduanjin: SMD = -0.83, 95% CI [-1.13, -0.53], P < 0.00001; 6 month treatment: SMD = -0.73, 95% CI [-1.20, -0.26], P = 0.002. (2) 2hPBG: SMD = -0.75, 95% CI [-0.94, -0.57], P < 0.00001; Baduanjin: SMD = -0.62, 95% CI [-0.91, -0.32], P < 0.00001; 6 month treatment: SMD = -0.91, 95% CI [-1.39, -0.44], P = 0.0002. (3) HbA1c: SMD = -0.56, 95% CI [-0.89, -0.23], P = 0.00008; Baduanjin: SMD = -0.46, 95% CI [-0.83, -0.08], P = 0.02; 6 month treatment: SMD = -0.77, 95% CI [-1.24, -0.29], P = 0.002. CONCLUSION TCEs had positive effects in improving blood glucose levels in patients with prediabetes. Hence, TCEs may be of potential therapeutic value for patients with prediabetes, as an adjuvant therapy along with other treatments. Although the evidence suggests that the intervention is effective for 6 months, the mechanism of TCEs on glycemic control, the minimum exercise dose and their safety remain to be further studied.
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Affiliation(s)
- Dong-Dong Yu
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Liang-Zhen You
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Wan-Qiu Huang
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Hui Cao
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Fan-Jing Wang
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Xiu-Qin Tang
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China
| | - Zhao-Hui Fang
- Endocrinology Department, the First Affiliated Hospital, Anhui University of Chinese Medicine, Hefei 230031, Anhui Province, China
| | - Guo-Ming Shen
- Graduate School, Anhui University of Chinese Medicine, Hefei 230038, Anhui Province, China.
| | - Yu-Xiang Guan
- Endocrinology Department, the First Affiliated Hospital, Anhui University of Chinese Medicine, Hefei 230031, Anhui Province, China.
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20
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Abstract
The conscious perception of the hedonic sensory properties of caloric foods is commonly believed to guide our dietary choices. Current and traditional models implicate the consciously perceived hedonic qualities of food as driving overeating, whereas subliminal signals arising from the gut would curb our uncontrolled desire for calories. Here we review recent animal and human studies that support a markedly different model for food reward. These findings reveal in particular the existence of subcortical body-to-brain neural pathways linking gastrointestinal nutrient sensors to the brain's reward regions. Unexpectedly, consciously perceptible hedonic qualities appear to play a less relevant, and mostly transient, role in food reinforcement. In this model, gut-brain reward pathways bypass cranial taste and aroma sensory receptors and the cortical networks that give rise to flavor perception. They instead reinforce behaviors independently of the cognitive processes that support overt insights into the nature of our dietary decisions.
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Affiliation(s)
- Ivan E. de Araujo
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
| | - Mark Schatzker
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
| | - Dana M. Small
- Modern Diet and Physiology Research Center, Yale University, New Haven, Connecticut 06511, USA
- Departments of Psychiatry and Psychology, Yale University, New Haven, Connecticut 06511, USA
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21
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Curtis K, Stewart CJ, Robinson M, Molfese DL, Gosnell SN, Kosten TR, Petrosino JF, De La Garza R, Salas R. Insular resting state functional connectivity is associated with gut microbiota diversity. Eur J Neurosci 2019; 50:2446-2452. [PMID: 30554441 DOI: 10.1111/ejn.14305] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 11/19/2018] [Accepted: 11/26/2018] [Indexed: 01/08/2023]
Abstract
The gut microbiota has recently gained attention as a possible modulator of brain activity. A number of reports suggest that the microbiota may be associated with neuropsychiatric conditions such as major depressive disorder, autism and anxiety. The gut microbiota is thought to influence the brain via vagus nerve signalling, among other possible mechanisms. The insula processes and integrates these vagal signals. To determine if microbiota diversity and structure modulate brain activity, we collected faecal samples and examined insular function using resting state functional connectivity (RSFC). Thirty healthy participants (non-smokers, tobacco smokers and electronic cigarette users, n = 10 each) were studied. We found that the RSFC between the insula and several regions (frontal pole left, lateral occipital cortex right, lingual gyrus right and cerebellum 4, 5 and vermis 9) were associated with bacterial microbiota diversity and structure. In addition, two specific bacteria genera, Prevotella and Bacteroides, were specifically different in tobacco smokers and also associated with insular connectivity. In conclusion, we show that insular connectivity is associated with microbiome diversity, structure and at least two specific bateria genera. Furthemore, this association is potentially modulated by tobacco smoking, although the sample sizes for the different smoking groups were small and this result needs validation in a larger cohort. While replication is necessary, the microbiota is a readily accessible therapeutic target for modulating insular connectivity, which has previously been shown to be abnormal in anxiety and tobacco use disorders.
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Affiliation(s)
- Kaylah Curtis
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA
| | - Christopher J Stewart
- Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Meghan Robinson
- Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA
| | - David L Molfese
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA
| | - Savannah N Gosnell
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Thomas R Kosten
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Joseph F Petrosino
- Alkek Center for Metagenomics and Microbiome Research, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
| | - Richard De La Garza
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Ramiro Salas
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, One Baylor Plaza, A277, Houston, TX, 77030, USA.,Michael E DeBakey VA Medical Center, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
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22
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Thanarajah SE, Backes H, DiFeliceantonio AG, Albus K, Cremer AL, Hanssen R, Lippert RN, Cornely OA, Small DM, Brüning JC, Tittgemeyer M. Food Intake Recruits Orosensory and Post-ingestive Dopaminergic Circuits to Affect Eating Desire in Humans. Cell Metab 2019; 29:695-706.e4. [PMID: 30595479 DOI: 10.1016/j.cmet.2018.12.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/18/2018] [Accepted: 12/04/2018] [Indexed: 01/07/2023]
Abstract
Pleasant taste and nutritional value guide food selection behavior. Here, orosensory features of food may be secondary to its nutritional value in underlying reinforcement, but it is unclear how the brain encodes the reward value of food. Orosensory and peripheral physiological signals may act together on dopaminergic circuits to drive food intake. We combined fMRI and a novel [11C]raclopride PET method to assess systems-level activation and dopamine release in response to palatable food intake in humans. We identified immediate orosensory and delayed post-ingestive dopamine release. Both responses recruit segregated brain regions: specialized integrative pathways and higher cognitive centers. Furthermore, we identified brain areas where dopamine release reflected the subjective desire to eat. Immediate dopamine release in these wanting-related regions was inversely correlated with, and presumably inhibited, post-ingestive release in the dorsal striatum. Our results highlight the role of brain and periphery in interacting to reinforce food intake in humans.
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Affiliation(s)
- Sharmili Edwin Thanarajah
- Max Planck Institute for Metabolism Research, Cologne, Germany; Department of Neurology, University Hospital of Cologne, Cologne, Germany
| | - Heiko Backes
- Max Planck Institute for Metabolism Research, Cologne, Germany.
| | - Alexandra G DiFeliceantonio
- Max Planck Institute for Metabolism Research, Cologne, Germany; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Modern Diet and Physiology Research Center, New Haven, CT, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kerstin Albus
- Cologne Cluster of Excellence in Cellular Stress and Aging-Associated Disease (CECAD), Cologne, Germany
| | | | - Ruth Hanssen
- Max Planck Institute for Metabolism Research, Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEPD), University Hospital of Cologne, Cologne, Germany
| | | | - Oliver A Cornely
- Cologne Cluster of Excellence in Cellular Stress and Aging-Associated Disease (CECAD), Cologne, Germany; Department I of Internal Medicine, University Hospital of Cologne, Cologne, Germany; Clinical Trials Centre Cologne (ZKS Köln), University of Cologne, Cologne, Germany
| | - Dana M Small
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Psychology, Yale University, New Haven, CT, USA; Modern Diet and Physiology Research Center, New Haven, CT, USA
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Cologne, Germany; Cologne Cluster of Excellence in Cellular Stress and Aging-Associated Disease (CECAD), Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEPD), University Hospital of Cologne, Cologne, Germany
| | - Marc Tittgemeyer
- Max Planck Institute for Metabolism Research, Cologne, Germany; Cologne Cluster of Excellence in Cellular Stress and Aging-Associated Disease (CECAD), Cologne, Germany; Modern Diet and Physiology Research Center, New Haven, CT, USA
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23
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Abstract
Taste pathways in humans and other primates project from the nucleus of the solitary tract directly to the taste thalamus, and then to the taste insula. The taste cortex in the anterior insula provides separate and combined representations of the taste, temperature, and texture of food in the mouth independently of hunger and thus of reward value and pleasantness. One synapse on, in the orbitofrontal cortex, these sensory inputs are for some neurons combined by associative learning with olfactory inputs received from the pyriform cortex, and visual inputs from the temporal lobe, and these neurons encode food reward value in that they only respond to food when hungry, and in that activations correlate linearly with subjective pleasantness. Cognitive factors, including word-level descriptions, and selective attention to affective value, modulate the representation of the reward value of taste, olfactory and flavor stimuli in the orbitofrontal cortex and a region to which it projects, the anterior cingulate cortex. These food reward representations are important in the control of appetite, and the liking of food. Individual differences in these reward representations may contribute to obesity, and there are age-related differences in these reward representations.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, United Kingdom.
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24
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Travers S, Breza J, Harley J, Zhu J, Travers J. Neurons with diverse phenotypes project from the caudal to the rostral nucleus of the solitary tract. J Comp Neurol 2018; 526:2319-2338. [PMID: 30325514 PMCID: PMC6193849 DOI: 10.1002/cne.24501] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 07/05/2018] [Accepted: 07/08/2018] [Indexed: 12/31/2022]
Abstract
The nucleus of the solitary tract is a potential site for taste-visceral interactions. Connections from the caudal, visceral area of the nucleus (cNST) to the rostral, gustatory zone (rNST) have been described, but the phenotype of cells giving rise to the projection(s) and their distribution among rNST subdivisions are unknown. To determine these characteristics of the intrasolitary pathway, we injected pan-neuronal and floxed AAV viruses into the cNST of mice expressing cre in glutamatergic, GABAergic, or catecholaminergic neurons. Particular attention was paid to the terminal field distribution in rNST subdivisions by simultaneously visualizing P2X2 localized to gustatory afferent terminals. All three phenotypically identified pathways terminated in rNST, with the density greatest for glutamatergic and sparsest for catecholaminergic projections, observations supported by retrograde tracing. Interestingly, cNST neurons had more prominent projections to rNST regions medial and ventral to P2X2 staining, i.e., the medial and ventral subdivisions. In addition, GABAergic neurons projected robustly to the lateral subdivision and adjacent parts of the reticular formation and spinal trigeminal nucleus. Although cNST neurons also projected to the P2X2-rich central subdivision, such projections were sparser. These findings suggest that cNST visceral signals exert stronger excitatory and inhibitory influences on local autonomic and reflex pathways associated with the medial and ventral subdivisions compared to weaker modulation of ascending pathways arising from the central subdivision and ultimately destined for the forebrain.
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Affiliation(s)
- Susan Travers
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, Ohio
| | - Joseph Breza
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, Ohio
| | - Jacob Harley
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, Ohio
| | - JiuLin Zhu
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, Ohio
| | - Joseph Travers
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, Ohio
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25
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Yu AP, Tam BT, Lai CW, Yu DS, Woo J, Chung KF, Hui SS, Liu JY, Wei GX, Siu PM. Revealing the Neural Mechanisms Underlying the Beneficial Effects of Tai Chi: A Neuroimaging Perspective. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2018. [PMID: 29542330 DOI: 10.1142/s0192415x18500131] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Tai Chi Chuan (TCC), a traditional Chinese martial art, is well-documented to result in beneficial consequences in physical and mental health. TCC is regarded as a mind-body exercise that is comprised of physical exercise and meditation. Favorable effects of TCC on body balance, gait, bone mineral density, metabolic parameters, anxiety, depression, cognitive function, and sleep have been previously reported. However, the underlying mechanisms explaining the effects of TCC remain largely unclear. Recently, advances in neuroimaging technology have offered new investigative opportunities to reveal the effects of TCC on anatomical morphologies and neurological activities in different regions of the brain. These neuroimaging findings have provided new clues for revealing the mechanisms behind the observed effects of TCC. In this review paper, we discussed the possible effects of TCC-induced modulation of brain morphology, functional homogeneity and connectivity, regional activity and macro-scale network activity on health. Moreover, we identified possible links between the alterations in brain and beneficial effects of TCC, such as improved motor functions, pain perception, metabolic profile, cognitive functions, mental health and sleep quality. This paper aimed to stimulate further mechanistic neuroimaging studies in TCC and its effects on brain morphology, functional homogeneity and connectivity, regional activity and macro-scale network activity, which ultimately lead to a better understanding of the mechanisms responsible for the beneficial effects of TCC on human health.
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Affiliation(s)
- Angus P Yu
- * School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Bjorn T Tam
- ‡ Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Christopher W Lai
- § Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China
| | - Doris S Yu
- ∥ The Nethersole School of Nursing, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Jean Woo
- ** Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Ka-Fai Chung
- † Department of Psychiatry, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Stanley S Hui
- †† Department of Sports Science and Physical Education, Faculty of Education, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Justina Y Liu
- ¶ School of Nursing, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China
| | - Gao X Wei
- ‡‡ Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Parco M Siu
- * School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
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26
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Han JE, Boachie N, Garcia-Garcia I, Michaud A, Dagher A. Neural correlates of dietary self-control in healthy adults: A meta-analysis of functional brain imaging studies. Physiol Behav 2018; 192:98-108. [PMID: 29496487 DOI: 10.1016/j.physbeh.2018.02.037] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/31/2018] [Accepted: 02/16/2018] [Indexed: 02/02/2023]
Affiliation(s)
- Jung Eun Han
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada, 3801 University Street, Montreal H3A 2B4, QC, Canada.
| | - Nadia Boachie
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada, 3801 University Street, Montreal H3A 2B4, QC, Canada.
| | - Isabel Garcia-Garcia
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada, 3801 University Street, Montreal H3A 2B4, QC, Canada.
| | - Andréanne Michaud
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada, 3801 University Street, Montreal H3A 2B4, QC, Canada.
| | - Alain Dagher
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada, 3801 University Street, Montreal H3A 2B4, QC, Canada.
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27
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Jiang H, Kim HF. Anatomical Inputs From the Sensory and Value Structures to the Tail of the Rat Striatum. Front Neuroanat 2018; 12:30. [PMID: 29773980 PMCID: PMC5943565 DOI: 10.3389/fnana.2018.00030] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 04/05/2018] [Indexed: 11/17/2022] Open
Abstract
The caudal region of the rodent striatum, called the tail of the striatum (TS), is a relatively small area but might have a distinct function from other striatal subregions. Recent primate studies showed that this part of the striatum has a unique function in encoding long-term value memory of visual objects for habitual behavior. This function might be due to its specific connectivity. We identified inputs to the rat TS and compared those with inputs to the dorsomedial striatum (DMS) in the same animals. The TS directly received anatomical inputs from both sensory structures and value-coding regions, but the DMS did not. First, inputs from the sensory cortex and sensory thalamus to the TS were found; visual, auditory, somatosensory and gustatory cortex and thalamus projected to the TS but not to the DMS. Second, two value systems innervated the TS; dopamine and serotonin neurons in the lateral part of the substantia nigra pars compacta (SNc) and dorsal raphe nucleus projected to the TS, respectively. The DMS received inputs from the separate group of dopamine neurons in the medial part of the SNc. In addition, learning-related regions of the limbic system innervated the TS; the temporal areas and the basolateral amygdala selectively innervated the TS, but not the DMS. Our data showed that both sensory and value-processing structures innervated the TS, suggesting its plausible role in value-guided sensory-motor association for habitual behavior.
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Affiliation(s)
- Haiyan Jiang
- Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon, South Korea
| | - Hyoung F Kim
- Center for Neuroscience Imaging Research, Institute for Basic Science (IBS), Suwon, South Korea.,Department of Biomedical Engineering, Sungkyunkwan University (SKKU), Suwon, South Korea
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28
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Avery JA, Powell JN, Breslin FJ, Lepping RJ, Martin LE, Patrician TM, Donnelly JE, Savage CR, Simmons WK. Obesity is associated with altered mid-insula functional connectivity to limbic regions underlying appetitive responses to foods. J Psychopharmacol 2017; 31:1475-1484. [PMID: 28944718 PMCID: PMC6527420 DOI: 10.1177/0269881117728429] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Obesity is fundamentally a disorder of energy balance. In obese individuals, more energy is consumed than is expended, leading to excessive weight gain through the accumulation of adipose tissue. Complications arising from obesity, including cardiovascular disease, elevated peripheral inflammation, and the development of Type II diabetes, make obesity one of the leading preventable causes of morbidity and mortality. Thus, it is of paramount importance to both individual and public health that we understand the neural circuitry underlying the behavioral regulation of energy balance. To this end, we sought to examine obesity-related differences in the resting state functional connectivity of the dorsal mid-insula, a region of gustatory and interoceptive cortex associated with homeostatically sensitive responses to food stimuli. Within the present study, obese and healthy weight individuals completed resting fMRI scans during varying interoceptive states, both while fasting and after a standardized meal. We examined group differences in the pre- versus post-meal functional connectivity of the mid-insula, and how those differences were related to differences in self-reported hunger ratings and ratings of meal pleasantness. Obese and healthy weight individuals exhibited opposing patterns of eating-related functional connectivity between the dorsal mid-insula and multiple brain regions involved in reward, valuation, and satiety, including the medial orbitofrontal cortex, the dorsal striatum, and the ventral striatum. In particular, healthy weight participants exhibited a significant positive relationship between changes in hunger and changes in medial orbitofrontal functional connectivity, while obese participants exhibited a complementary negative relationship between hunger and ventral striatum connectivity to the mid-insula. These obesity-related alterations in dorsal mid-insula functional connectivity patterns may signify a fundamental difference in the experience of food motivation in obese individuals, wherein approach behavior toward food is guided more by reward-seeking than by homeostatically relevant interoceptive information from the body.
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Affiliation(s)
| | - Joshua N. Powell
- Laureate Institute for Brain Research, Tulsa, OK,Center for Health Behavior Neuroscience, University of Kansas Medical Center, Kansas City, KS,Graduate School of Social Work, University of Denver, Denver, CO
| | - Florence J. Breslin
- Laureate Institute for Brain Research, Tulsa, OK,Center for Health Behavior Neuroscience, University of Kansas Medical Center, Kansas City, KS
| | - Rebecca J. Lepping
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, KS
| | - Laura E. Martin
- Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, KS
| | | | - Joseph E. Donnelly
- Center for Physical Activity and Weight Management, University of Kansas Medical Center, Kansas City, KS
| | - Cary R. Savage
- Center for Health Behavior Neuroscience, University of Kansas Medical Center, Kansas City, KS,Center for Physical Activity and Weight Management, University of Kansas Medical Center, Kansas City, KS
| | - W. Kyle Simmons
- Laureate Institute for Brain Research, Tulsa, OK,Banner Alzheimer’s Institute, Phoenix, AZ
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29
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Cameron JD, Chaput JP, Sjödin AM, Goldfield GS. Brain on Fire: Incentive Salience, Hedonic Hot Spots, Dopamine, Obesity, and Other Hunger Games. Annu Rev Nutr 2017; 37:183-205. [PMID: 28564556 DOI: 10.1146/annurev-nutr-071816-064855] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review examines human feeding behavior in light of psychological motivational theory and highlights the importance of midbrain dopamine (DA). Prospective evidence of both reward surfeit and reward deficit pathways to increased body weight are evaluated, and we argue that it is more complex than an either/or scenario when examining DA's role in reward sensitivity, eating, and obesity. The Taq1A genotype is a common thread that ties the contrasting models of DA reward and obesity; this genotype related to striatal DA is not associated with obesity class per se but may nevertheless confer an increased risk of weight gain. We also critically examine the concept of so-called food addiction, and despite growing evidence, we argue that there is currently insufficient human data to warrant this diagnostic label. The surgical and pharmacological treatments of obesity are discussed, and evidence is presented for the selective use of DA-class drugs in obesity treatment.
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Affiliation(s)
- Jameason D Cameron
- Healthy Active Living and Obesity (HALO) Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 5B2, Canada; , ,
| | - Jean-Philippe Chaput
- Healthy Active Living and Obesity (HALO) Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 5B2, Canada; , ,
| | - Anders M Sjödin
- Department of Nutrition, Exercise and Sports, Faculty of Sciences, University of Copenhagen, 1165 Copenhagen, Denmark;
| | - Gary S Goldfield
- Healthy Active Living and Obesity (HALO) Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario K1H 5B2, Canada; , ,
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30
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Avery JA, Gotts SJ, Kerr KL, Burrows K, Ingeholm JE, Bodurka J, Martin A, Kyle Simmons W. Convergent gustatory and viscerosensory processing in the human dorsal mid-insula. Hum Brain Mapp 2017; 38:2150-2164. [PMID: 28070928 DOI: 10.1002/hbm.23510] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 11/06/2022] Open
Abstract
The homeostatic regulation of feeding behavior requires an organism to be able to integrate information from its internal environment, including peripheral visceral signals about the body's current energy needs, with information from its external environment, such as the palatability of energy-rich food stimuli. The insula, which serves as the brain's primary sensory cortex for representing both visceral signals from the body and taste signals from the mouth and tongue, is a likely candidate region in which this integration might occur. However, to date it has been unclear whether information from these two homeostatically critical faculties is merely co-represented in the human insula, or actually integrated there. Recent functional neuroimaging evidence of a common substrate for visceral interoception and taste perception within the human dorsal mid-insula suggests a model whereby a single population of neurons may integrate viscerosensory and gustatory signals. To test this model, we used fMRI-Adaptation to identify whether insula regions that exhibit repetition suppression following repeated interoception trials would then also exhibit adapted responses to subsequent gustatory stimuli. Multiple mid and anterior regions of the insula exhibited adaptation to interoceptive trials specifically, but only the dorsal mid-insula regions exhibited an adapted gustatory response following interoception. The discovery of this gustatory-interoceptive convergence within the neurons of the human insula supports the existence of a heretofore-undocumented neural pathway by which visceral signals from the periphery modulate the activity of brain regions involved in feeding behavior. Hum Brain Mapp 38:2150-2164, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Jason A Avery
- Laureate Institute for Brain Research, Tulsa, Oklahoma.,Department of Biological Sciences, The University of Tulsa, Tulsa, Oklahoma
| | - Stephen J Gotts
- Laboratory of Brain and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Bethesda, Maryland
| | - Kara L Kerr
- Laureate Institute for Brain Research, Tulsa, Oklahoma.,Department of Psychology, The University of Tulsa, Tulsa, Oklahoma
| | | | - John E Ingeholm
- Laboratory of Brain and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Bethesda, Maryland
| | - Jerzy Bodurka
- Laureate Institute for Brain Research, Tulsa, Oklahoma
| | - Alex Martin
- Laboratory of Brain and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Bethesda, Maryland
| | - W Kyle Simmons
- Laureate Institute for Brain Research, Tulsa, Oklahoma.,School of Community Medicine, The University of Tulsa, Tulsa, Oklahoma
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31
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Micturition Drive is Associated with Decreased Brain Response to Palatable Milkshake in the Human Anterior Insular Cortex. CHEMOSENS PERCEPT 2016. [DOI: 10.1007/s12078-016-9215-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Iranpour J, Morrot G, Claise B, Jean B, Bonny JM. Using High Spatial Resolution to Improve BOLD fMRI Detection at 3T. PLoS One 2015; 10:e0141358. [PMID: 26550990 PMCID: PMC4638337 DOI: 10.1371/journal.pone.0141358] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/07/2015] [Indexed: 11/19/2022] Open
Abstract
For different functional magnetic resonance imaging experiments using blood oxygenation level-dependent (BOLD) contrast, the acquisition of T2*-weighted scans at a high spatial resolution may be advantageous in terms of time-course signal-to-noise ratio and of BOLD sensitivity when the regions are prone to susceptibility artifacts. In this study, we explore this solution by examining how spatial resolution influences activations elicited when appetizing food pictures are viewed. Twenty subjects were imaged at 3 T with two different voxel volumes, 3.4 μl and 27 μl. Despite the diminution of brain coverage, we found that high-resolution acquisition led to a better detection of activations. Though known to suffer to different degrees from susceptibility artifacts, the activations detected by high spatial resolution were notably consistent with those reported in published activation likelihood estimation meta-analyses, corresponding to taste-responsive regions. Furthermore, these regions were found activated bilaterally, in contrast with previous findings. Both the reduction of partial volume effect, which improves BOLD contrast, and the mitigation of susceptibility artifact, which boosts the signal to noise ratio in certain regions, explained the better detection noted with high resolution. The present study provides further evidences that high spatial resolution is a valuable solution for human BOLD fMRI, especially for studying food-related stimuli.
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Affiliation(s)
| | - Gil Morrot
- Laboratoire Charles Coulomb—UMR 5221 CNRS, Université des Sciences et Techniques—Montpellier 2, place Eugène-Bataillon, 34090, Montpellier, France
| | - Béatrice Claise
- Neuroradiologie A, Plateforme Recherche IRM—CHU Gabriel-Montpied, F63000, Clermont-Ferrand, France
| | - Betty Jean
- Neuroradiologie A, Plateforme Recherche IRM—CHU Gabriel-Montpied, F63000, Clermont-Ferrand, France
| | - Jean-Marie Bonny
- UR370 QuaPA—INRA, F-63122, Saint-Genès-Champanelle, France
- * E-mail:
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33
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Rolls ET. Functions of the anterior insula in taste, autonomic, and related functions. Brain Cogn 2015; 110:4-19. [PMID: 26277487 DOI: 10.1016/j.bandc.2015.07.002] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/10/2015] [Accepted: 07/11/2015] [Indexed: 10/23/2022]
Abstract
The anterior insula contains the primary taste cortex, in which neurons in primates respond to different combinations providing a distributed representation of different prototypical tastes, oral texture including fat texture, and oral temperature. These taste neurons do not represent food reward value, in that feeding to satiety does not reduce their responses to zero, in contrast to the next stage of processing, the orbitofrontal cortex, where food reward value is represented. Corresponding results are found with fMRI in humans. A more ventral part of the anterior insula is implicated using fMRI in autonomic-visceral functions. 'Salient' stimuli, including rewarding, punishing, non-rewarding, and novel stimuli may activate this viscero-autonomic system, via inputs received from regions that represent these stimuli such as the orbitofrontal and anterior cingulate cortex. More posteriorly in the insula, there is an oral somatosensory region, and posterior to this somatosensory regions that respond to touch to the body. These taste and somatosensory representations in the insula provide representations that are about the external world (touch), are intermediate (oral taste and texture), and are about internal signals related to visceral and autonomic function. This functionality needs to be taken into account when considering activations of the insula found in cognitive tasks.
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Affiliation(s)
- Edmund T Rolls
- Oxford Centre for Computational Neuroscience, Oxford, UK.
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34
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Avery JA, Kerr KL, Ingeholm JE, Burrows K, Bodurka J, Simmons WK. A common gustatory and interoceptive representation in the human mid-insula. Hum Brain Mapp 2015; 36:2996-3006. [PMID: 25950427 DOI: 10.1002/hbm.22823] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 03/27/2015] [Accepted: 04/16/2015] [Indexed: 11/10/2022] Open
Abstract
The insula serves as the primary gustatory and viscerosensory region in the mammalian cortex. It receives visceral and gustatory afferent projections through dedicated brainstem and thalamic nuclei, which suggests a potential role as a site for homeostatic integration. For example, while human neuroimaging studies of gustation have implicated the dorsal mid-insular cortex as one of the primary gustatory regions in the insula, other recent studies have implicated this same region of the insula in interoception. This apparent convergence of gustatory and interoceptive information could reflect a common neural representation in the insula shared by both interoception and gustation. This idea finds support in translational studies in rodents, and may constitute a medium for integrating homeostatic information with feeding behavior. To assess this possibility, healthy volunteers were asked to undergo fMRI while performing tasks involving interoceptive attention to visceral sensations as well as a gustatory mapping task. Analysis of the unsmoothed, high-resolution fMRI data confirmed shared representations of gustatory and visceral interoception within the dorsal mid-insula. Group conjunction analysis revealed overlapping patterns of activation for both tasks in the dorsal mid-insula, and region-of-interest analyses confirmed that the dorsal mid-insula regions responsive for visceral interoception also exhibit strong responses to tastants.
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Affiliation(s)
- Jason A Avery
- Laureate Institute for Brain Research, Tulsa, Oklahoma, 74136.,Department of Biological Sciences, The University of Tulsa, Tulsa, Oklahoma, 74104
| | - Kara L Kerr
- Laureate Institute for Brain Research, Tulsa, Oklahoma, 74136.,Department of Psychology, The University of Tulsa, Tulsa, Oklahoma, 74104
| | - John E Ingeholm
- Laboratory of Brain and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health (NIH), Bethesda, Maryland, 20892
| | - Kaiping Burrows
- Laureate Institute for Brain Research, Tulsa, Oklahoma, 74136
| | - Jerzy Bodurka
- Laureate Institute for Brain Research, Tulsa, Oklahoma, 74136.,College of Engineering, The University of Oklahoma, Norman, Oklahoma, 73071.,Center for Biomedical Engineering, The University of Oklahoma, Norman, Oklahoma, 73071
| | - W Kyle Simmons
- Laureate Institute for Brain Research, Tulsa, Oklahoma, 74136.,Department of Community Medicine, The University of Tulsa, Tulsa, Oklahoma, 74104
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35
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Rolls ET. Taste, olfactory, and food reward value processing in the brain. Prog Neurobiol 2015; 127-128:64-90. [DOI: 10.1016/j.pneurobio.2015.03.002] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 03/03/2015] [Accepted: 03/15/2015] [Indexed: 01/10/2023]
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36
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Tang DW, Fellows LK, Dagher A. Behavioral and neural valuation of foods is driven by implicit knowledge of caloric content. Psychol Sci 2014; 25:2168-76. [PMID: 25304885 DOI: 10.1177/0956797614552081] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The factors that affect food choices are critical to understanding obesity. In the present study, healthy participants were shown pictures of foods to determine the impact of caloric content on food choice. Brain activity was then measured while participants bid for a chance to purchase and eat one item. True caloric density, but not individual estimates of calorie content, predicted how much participants were willing to pay for each item. Caloric density also correlated with the neural response to food pictures in the ventromedial prefrontal cortex, a brain area that encodes the value of stimuli and predicts immediate consumption. That same region exhibited functional connectivity with an appetitive brain network, and this connectivity was modulated by willingness to pay. Despite the fact that participants were poor at explicitly judging caloric content, their willingness to pay and brain activity both correlated with actual caloric density. This suggests that the reward value of a familiar food is dependent on implicit knowledge of its caloric content.
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37
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Geha P, deAraujo I, Green B, Small DM. Decreased food pleasure and disrupted satiety signals in chronic low back pain. Pain 2014; 155:712-722. [DOI: 10.1016/j.pain.2013.12.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 12/10/2013] [Accepted: 12/20/2013] [Indexed: 01/22/2023]
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38
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de Araujo IE, Lin T, Veldhuizen MG, Small DM. Metabolic regulation of brain response to food cues. Curr Biol 2013; 23:878-83. [PMID: 23643837 DOI: 10.1016/j.cub.2013.04.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 03/06/2013] [Accepted: 04/02/2013] [Indexed: 11/20/2022]
Abstract
Identification of energy sources depends upon the ability to form associations between food cues and nutritional value. As such, cues previously paired with calories elicit neuronal activation in the nucleus accumbens (NAcc), which reflects the reinforcing value of food. The identity of the physiological signals regulating this response remains elusive. Using fMRI, we examined brain response to noncaloric versions of flavors that had been consumed in previous days with either 0 or 112.5 calories from undetected maltodextrin. We report a small but perceptually meaningful increase in liking for the flavor that had been paired with calories and find that change in liking was associated with changes in insular responses to this beverage. In contrast, NAcc and hypothalamic response to the calorie-paired flavor was unrelated to liking but was strongly associated with the changes in plasma glucose levels produced by ingestion of the beverage when consumed previously with calories. Importantly, because each participant ingested the same caloric dose, the change in plasma glucose depended upon individual differences in glucose metabolism. We conclude that glucose metabolism is a critical signal regulating NAcc and hypothalamic response to food cues, and that this process operates independently from the ability of calories to condition liking.
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Nakamura Y, Tokumori K, Tanabe HC, Yoshiura T, Kobayashi K, Nakamura Y, Honda H, Yoshiura K, Goto TK. Localization of the primary taste cortex by contrasting passive and attentive conditions. Exp Brain Res 2013; 227:185-97. [PMID: 23604572 DOI: 10.1007/s00221-013-3499-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/22/2013] [Indexed: 11/30/2022]
Abstract
The primary taste cortex is located in the insula. However, exactly where in the insula the human primary taste cortex is located remains a controversial issue. Human neuroimaging studies have shown prominent variation concerning the location of taste-responsive activation within the insula. A standard protocol for gustatory testing in neuroimaging studies has not been developed, which might underlie such variations. In order to localize the primary taste cortex in an fMRI experiment, we used a taste delivery system to suppress non-taste stimuli and psychological effects. Then, we compared brain response to taste solution during a passive tasting task condition and a taste quality identification task condition to verify whether this cognitive task affected the location of taste-responsive activation within the insula. To examine which part of insula is the primary taste area, we performed dynamic causal modeling (DCM) to verify the neural network of the taste coding-related region and random-effects Bayesian model selection (BMS) at the family level to reveal the optimal input region. Passive tasting resulted in activation of the right middle insula (MI), and the most favorable model selected by DCM analysis showed that taste effect directly influenced the MI. Additionally, BMS results at the family level suggested that the taste inputs entered into the MI. Taken together, our results suggest that the human primary taste cortex is located in the MI.
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Affiliation(s)
- Yuko Nakamura
- Department of Oral and Maxillofacial Radiology, Faculty of Dental Science, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
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Abstract
PURPOSE OF REVIEW Eating behavior depends heavily on brain function. In recent years, brain imaging has proved to be a powerful tool to elucidate brain function and brain structure in the context of eating. In this review, we summarize recent findings in the fast growing body of literature in the field and provide an overview of technical aspects as well as the basic brain mechanisms identified with imaging. Furthermore, we highlight findings linking neural processing of eating-related stimuli with obesity. RECENT FINDINGS The consumption of food is based on a complex interplay between homeostatic and hedonic mechanisms. Several hormones influence brain activity to regulate food intake and interact with the brain's reward circuitry, which is partly mediated by dopamine signaling. Additionally, it was shown that food stimuli trigger cognitive control mechanisms that incorporate internal goals into food choice. The brain mechanisms observed in this context are strongly influenced by genetic factors, sex and personality traits. SUMMARY Overall, a complex picture arises from brain-imaging findings, because a multitude of factors influence human food choice. Although several key mechanisms have been identified, there is no comprehensive model that is able to explain the behavioral observations to date. Especially a careful characterization of patients according to genotypes and phenotypes could help to better understand the current and future findings in neuroimaging studies.
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Affiliation(s)
- Maurice Hollmann
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
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Dagher A. Functional brain imaging of appetite. Trends Endocrinol Metab 2012; 23:250-60. [PMID: 22483361 DOI: 10.1016/j.tem.2012.02.009] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/22/2012] [Accepted: 02/28/2012] [Indexed: 01/01/2023]
Abstract
Obesity is a neurobehavioral disorder that results from a combination of overeating and insufficient physical activity. Finely tuned mechanisms exist to match food intake to caloric expenditure. However, faced with abundant inexpensive and calorie-dense foods, many humans (and perhaps most) have a tendency to consume beyond their caloric needs. The brain controls food intake by sensing internal energy-balance signals and external cues of food availability, and by controlling feeding behavior; it is therefore at the centre of the obesity problem. This article reviews the recent use of functional brain imaging in humans to study the neural control of appetite, and how the neural systems involved may cause vulnerability to overeating in the obesogenic environment.
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Affiliation(s)
- Alain Dagher
- Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, Quebec, H3A 2B4, Canada.
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Food and drug cues activate similar brain regions: a meta-analysis of functional MRI studies. Physiol Behav 2012; 106:317-24. [PMID: 22450260 DOI: 10.1016/j.physbeh.2012.03.009] [Citation(s) in RCA: 291] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 01/17/2023]
Abstract
In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards.
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