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Philipsen MH, Ranjbari E, Gu C, Ewing AG. Mass Spectrometry Imaging Shows Modafinil, A Student Study Drug, Changes the Lipid Composition of the Fly Brain. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mai H. Philipsen
- Department of Chemistry and Molecular Biology University of Gothenburg Kemigården 4 41296 Göteborg Sweden
| | - Elias Ranjbari
- Department of Chemistry and Molecular Biology University of Gothenburg Kemigården 4 41296 Göteborg Sweden
| | - Chaoyi Gu
- Department of Chemistry and Molecular Biology University of Gothenburg Kemigården 4 41296 Göteborg Sweden
| | - Andrew G. Ewing
- Department of Chemistry and Molecular Biology University of Gothenburg Kemigården 4 41296 Göteborg Sweden
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Philipsen MH, Ranjbari E, Gu C, Ewing AG. Mass Spectrometry Imaging Shows Modafinil, A Student Study Drug, Changes the Lipid Composition of the Fly Brain. Angew Chem Int Ed Engl 2021; 60:17378-17382. [PMID: 34041832 PMCID: PMC8361715 DOI: 10.1002/anie.202105004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Indexed: 12/17/2022]
Abstract
Modafinil, a widely used psychoactive drug, has been shown to exert a positive impact on cognition and is used to treat sleep disorders and hyperactivity. Using time-of-flight secondary ion mass spectrometric imaging, we studied the changes of brain lipids of Drosophila melanogaster induced by modafinil to gain insight into the functional mechanism of modafinil in the brain. We found that upon modafinil treatment, the abundance of phosphatidylcholine and sphingomyelin species in the central brain of Drosophila is significantly decreased, whereas the levels of phosphatidylethanolamine and phosphatidylinositol in the brains show significant enhancement compared to the control flies. The alteration of brain lipids caused by modafinil is consistent with previous studies about cognition-related drugs and offers a plausible mechanism regarding the action of modafinil in the brain as well as a potential target for the treatment of certain disorders.
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Affiliation(s)
- Mai H. Philipsen
- Department of Chemistry and Molecular BiologyUniversity of GothenburgKemigården 441296GöteborgSweden
| | - Elias Ranjbari
- Department of Chemistry and Molecular BiologyUniversity of GothenburgKemigården 441296GöteborgSweden
| | - Chaoyi Gu
- Department of Chemistry and Molecular BiologyUniversity of GothenburgKemigården 441296GöteborgSweden
| | - Andrew G. Ewing
- Department of Chemistry and Molecular BiologyUniversity of GothenburgKemigården 441296GöteborgSweden
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3
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Perez-Martinez CA, Leal M. Lizards as models to explore the ecological and neuroanatomical correlates of miniaturization. BEHAVIOUR 2021. [DOI: 10.1163/1568539x-bja10104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Extreme body size reductions bring about unorthodox anatomical arrangements and novel ways in which animals interact with the environment. Drawing from studies of vertebrates and invertebrates, we provide a theoretical framework for miniaturization to inform hypotheses using lizards as a study system. Through this approach, we demonstrate the repeated evolution of miniaturization across 11 families and a tendency for miniaturized species to occupy terrestrial microhabitats, possibly driven by physiological constraints. Differences in gross brain morphology between two gecko species demonstrate a proportionally larger telencephalon and smaller olfactory bulbs in the miniaturized species, though more data are needed to generalize this trend. Our study brings into light the potential contributions of miniaturized lizards to explain patterns of body size evolution and its impact on ecology and neuroanatomy. In addition, our findings reveal the need to study the natural history of miniaturized species, particularly in relation to their sensory and physiological ecology.
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Affiliation(s)
| | - Manuel Leal
- Division of Biological Sciences, University of Missouri, Columbia, MO 65201, USA
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4
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Romano D, Benelli G, Stefanini C. Opposite valence social information provided by bio-robotic demonstrators shapes selection processes in the green bottle fly. J R Soc Interface 2021; 18:20210056. [PMID: 33726543 PMCID: PMC8086872 DOI: 10.1098/rsif.2021.0056] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/23/2021] [Indexed: 02/05/2023] Open
Abstract
Social learning represents a high-level complex process to acquire information about the environment, which is increasingly reported in invertebrates. The animal-robot interaction paradigm turned out to be an encouraging strategy to unveil social learning in vertebrates, but it has not been fully exploited in invertebrates. In this study, Lucilia sericata adults were induced to observe bio-robotic conspecific and predator demonstrators to reproduce different flower foraging choices. Can a fly manage two flows of social information with opposite valence? Herein, we attempt a reply. The selection process of L. sericata was affected by social information provided through different bio-robotic demonstrators, by avoiding coloured discs previously visited by a bio-robotic predator and preferring coloured discs previously visited by a bio-robotic conspecific. When both bio-robotic demonstrators visited the same disc, the latency duration increased and the flies significantly tended to avoid this disc. This indicates the complex risk-benefit evaluation process carried out by L. sericata during the acquisition of such social information. Overall, this article provides a unique perspective on the behavioural ecology of social learning in non-social insects; it also highlights the high potential of the animal-robot interaction approach for unveiling the full spectrum of invertebrates' abilities in using social information.
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Affiliation(s)
- Donato Romano
- The BioRobotics Institute, Sant'Anna School of Advanced Studies, viale Rinaldo Piaggio 34, Pisa, Pontedera 56025, Italy
- Department of Excellence in Robotics and AI, Sant'Anna School of Advanced Studies, Pisa 56127, Italy
| | - Giovanni Benelli
- Department of Agriculture, Food and Environment, University of Pisa, via del Borghetto 80, Pisa 56124, Italy
| | - Cesare Stefanini
- The BioRobotics Institute, Sant'Anna School of Advanced Studies, viale Rinaldo Piaggio 34, Pisa, Pontedera 56025, Italy
- Department of Excellence in Robotics and AI, Sant'Anna School of Advanced Studies, Pisa 56127, Italy
- Healthcare Engineering Innovation Center (HEIC), Khalifa University, Abu Dhabi, United Arab Emirates
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5
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Leung A, Cohen D, van Swinderen B, Tsuchiya N. Integrated information structure collapses with anesthetic loss of conscious arousal in Drosophila melanogaster. PLoS Comput Biol 2021; 17:e1008722. [PMID: 33635858 PMCID: PMC7946294 DOI: 10.1371/journal.pcbi.1008722] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 03/10/2021] [Accepted: 01/18/2021] [Indexed: 01/12/2023] Open
Abstract
The physical basis of consciousness remains one of the most elusive concepts in current science. One influential conjecture is that consciousness is to do with some form of causality, measurable through information. The integrated information theory of consciousness (IIT) proposes that conscious experience, filled with rich and specific content, corresponds directly to a hierarchically organised, irreducible pattern of causal interactions; i.e. an integrated informational structure among elements of a system. Here, we tested this conjecture in a simple biological system (fruit flies), estimating the information structure of the system during wakefulness and general anesthesia. Consistent with this conjecture, we found that integrated interactions among populations of neurons during wakefulness collapsed to isolated clusters of interactions during anesthesia. We used classification analysis to quantify the accuracy of discrimination between wakeful and anesthetised states, and found that informational structures inferred conscious states with greater accuracy than a scalar summary of the structure, a measure which is generally championed as the main measure of IIT. In stark contrast to a view which assumes feedforward architecture for insect brains, especially fly visual systems, we found rich information structures, which cannot arise from purely feedforward systems, occurred across the fly brain. Further, these information structures collapsed uniformly across the brain during anesthesia. Our results speak to the potential utility of the novel concept of an “informational structure” as a measure for level of consciousness, above and beyond simple scalar values. The physical basis of consciousness remains elusive. Efforts to measure consciousness have generally been restricted to simple, scalar quantities which summarise the complexity of a system, inspired by integrated information theory, which links a multi-dimensional, informational structure to the contents of experience in a system. Due to the complexity of the definition of the structure, assessment of its utility as a measure of conscious arousal in a system has largely been ignored. In this manuscript we evaluate the utility of such an information structure in measuring the level of arousal in the fruit fly. Our results indicate that this structure can be more informative about the level of arousal in a system than even the single-value summary proposed by the theory itself. These results may push consciousness research towards the notion of multi-dimensional informational structures, instead of traditional scalar summaries.
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Affiliation(s)
- Angus Leung
- School of Psychological Sciences, Monash University, Melbourne, Australia
- * E-mail: (AL); (NT)
| | - Dror Cohen
- School of Psychological Sciences, Monash University, Melbourne, Australia
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Osaka, Japan
| | - Bruno van Swinderen
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | - Naotsugu Tsuchiya
- School of Psychological Sciences, Monash University, Melbourne, Australia
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Osaka, Japan
- Monash Institute of Cognitive and Clinical Neuroscience (MICCN), Monash University, Melbourne, Australia
- Advanced Telecommunications Research Computational Neuroscience Laboratories, Kyoto, Japan
- * E-mail: (AL); (NT)
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Naz F, Rahul, Fatima M, Naseem S, Khan W, Mondal AC, Siddique YH. Ropinirole silver nanocomposite attenuates neurodegeneration in the transgenic Drosophila melanogaster model of Parkinson's disease. Neuropharmacology 2020; 177:108216. [PMID: 32707222 DOI: 10.1016/j.neuropharm.2020.108216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/06/2020] [Accepted: 06/15/2020] [Indexed: 12/11/2022]
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disease due to the degeneration of dopaminergic neurons in substantia nigra pars compacta of the mid brain. The present study investigates the neuro-protective role of synthesized ropinirole silver nanocomposite (RPAgNC) in Drosophila model of PD. α-synuclein accumulation in the brain of flies (PD flies) leads to the damage of dopaminergic neurons, dopamine depletion, impaired muscular coordination, memory decline and increase in oxidative stress. Ingestion of the RPAgNC by Drosophila significantly prevented the neuronal degeneration compared to only ropinirole. The results confirm that the RPAgNC exerts more neuro-protective effect compared to dopamine agonist i.e. ropinirole as such drug in experimental PD flies. This article is part of the special issue entitled 'The Quest for Disease-Modifying Therapies for Neurodegenerative Disorders'.
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Affiliation(s)
- Falaq Naz
- Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India
| | - Rahul
- Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India
| | - Mahino Fatima
- Laboratory of Cellular and Molecular Neurobiology, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Swaleha Naseem
- Interdisciplinary Nanotechnology Centre, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India
| | - Wasi Khan
- Department of Physics, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India
| | - Amal Chandra Mondal
- Laboratory of Cellular and Molecular Neurobiology, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Yasir Hasan Siddique
- Drosophila Transgenic Laboratory, Section of Genetics, Department of Zoology, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, 202002, Uttar Pradesh, India.
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An infection of Enterobacter ludwigii affects development and causes age-dependent neurodegeneration in Drosophila melanogaster. INVERTEBRATE NEUROSCIENCE 2019; 19:13. [PMID: 31641932 DOI: 10.1007/s10158-019-0233-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 10/10/2019] [Indexed: 02/06/2023]
Abstract
The effects of teeth-blackening bacteria Enterobacter ludwigii on the physiological system were investigated using the model organism Drosophila melanogaster. The bacteria were mixed with the fly food, and its effect was checked on the growth, development and behaviour of Drosophila. Microbes generate reactive oxygen species (ROS) within the haemolymph of the larvae once it enters into the body. The increased amount of ROS was evidenced by the NBT assay and using 2',7'-dichlorofluorescin diacetate dye, which indicates the mitochondrial ROS. The increased amount of ROS resulted in a number of abnormal nuclei within the gut. Besides that larvae walking became sluggish in comparison with wild type although the larvae crawling path did not change much. Flies hatched from the infectious larvae have the posterior scutellar bristle absent from the thorax and abnormal mechanosensory hairs in the eye, and they undergo time-dependent neurodegeneration as evidenced by the geotrophic and phototrophic assays. To decipher the mechanism of neurodegeneration, flies were checked for the presence of four important bioamines: tyramine, cadaverine, putrescine and histamine. Out of these four, histamine was found to be absent in infected flies. Histamine is a key molecule required for the functioning of the photoreceptor as well as mechanoreceptors. The mechanism via which mouth infectious bacteria E. ludwigii can affect the development and cause age-dependent neurodegeneration is explained in this paper.
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Sharma N, Khurana N, Muthuraman A. Lower vertebrate and invertebrate models of Alzheimer's disease - A review. Eur J Pharmacol 2017; 815:312-323. [PMID: 28943103 DOI: 10.1016/j.ejphar.2017.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/20/2017] [Accepted: 09/13/2017] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease is a common neurodegenerative disorder which is characterized by the presence of beta- amyloid protein and neurofibrillary tangles (NFTs) in the brain. Till now, various higher vertebrate models have been in use to study the pathophysiology of this disease. But, these models possess some limitations like ethical restrictions, high cost, difficult maintenance of large quantity and lesser reproducibility. Besides, various lower chordate animals like Danio rerio, Drosophila melanogaster, Caenorhabditis elegans and Ciona intestinalis have been proved to be an important model for the in vivo determination of targets of drugs with least limitations. In this article, we reviewed different studies conducted on theses models for the better understanding of the pathophysiology of AD and their subsequent application as a potential tool in the preclinical evaluation of new drugs.
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Affiliation(s)
- Neha Sharma
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Navneet Khurana
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Arunachalam Muthuraman
- Department of Pharmacology, Akal College of Pharmacy and Technical Education, Mastuana Sahib, Sangrur, Punjab, India; Department of Pharmacology, JSS College of Pharmacy, Jagadguru Sri Shivarathreeshwara University, Mysuru 570015, Karnataka, India.
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9
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10
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Exploring miniature insect brains using micro-CT scanning techniques. Sci Rep 2016; 6:21768. [PMID: 26908205 PMCID: PMC4764865 DOI: 10.1038/srep21768] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 01/29/2016] [Indexed: 01/10/2023] Open
Abstract
The capacity to explore soft tissue structures in detail is important in understanding animal physiology and how this determines features such as movement, behaviour and the impact of trauma on regular function. Here we use advances in micro-computed tomography (micro-CT) technology to explore the brain of an important insect pollinator and model organism, the bumblebee (Bombus terrestris). Here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue free from trauma and in its natural stereo-geometry, and showcase our 3D reconstructions and analyses of 19 individual brains at high resolution. Development of this protocol allows relatively rapid and cost effective brain reconstructions, making it an accessible methodology to the wider scientific community. The protocol describes the necessary steps for sample preparation, tissue staining, micro-CT scanning and 3D reconstruction, followed by a method for image analysis using the freeware SPIERS. These image analysis methods describe how to virtually extract key composite structures from the insect brain, and we demonstrate the application and precision of this method by calculating structural volumes and investigating the allometric relationships between bumblebee brain structures.
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11
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König C, Schleyer M, Leibiger J, El-Keredy A, Gerber B. Bitter-sweet processing in larval Drosophila. Chem Senses 2014; 39:489-505. [PMID: 24833133 DOI: 10.1093/chemse/bju016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
"Sweet-" and "bitter-" tasting substances distinctively support attractive and aversive choice behavior, respectively, and therefore are thought to be processed by distinct pathways. Interestingly, electrophysiological recordings in adult Drosophila suggest that bitter and salty tastants, in addition to activating bitter, salt, or bitter/salt sensory neurons, can also inhibit sweet-sensory neurons. However, the behavioral significance of such a potential for combinatorial coding is little understood. Using larval Drosophila as a study case, we find that the preference towards fructose is inhibited when assayed in the background of the bitter tastant quinine. When testing the influence of quinine on the preference to other, equally preferred sweet tastants, we find that these sweet tastants differ in their susceptibility to be inhibited by quinine. Such stimulus specificity argues that the inhibitory effect of quinine is not due to general effects on locomotion or nausea. In turn, not all bitter tastants have the same potency to inhibit sweet preference; notably, their inhibitory potency is not determined by the strength of the avoidance of them. Likewise, equally avoided concentrations of sodium chloride differ in their potency to inhibit sugar preference. Furthermore, Gr33a-Gal4-positive neurons, while being necessary for bitter avoidance, are dispensable for inhibition of the sweet pathway. Thus, interactions across taste modalities are behaviorally significant and, as we discuss, arguably diverse in mechanism. These results suggest that the coding of tastants and the organization of gustatory behavior may be more combinatorial than is generally acknowledged.
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Affiliation(s)
- Christian König
- Department of Genetics, Institute of Biology, University of Leipzig, Talstr. 33, 04103 Leipzig, Germany, Research Group Molecular Systems Biology of Learning, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
| | - Michael Schleyer
- Department of Genetics, Institute of Biology, University of Leipzig, Talstr. 33, 04103 Leipzig, Germany, Department of Genetics of Learning and Memory, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
| | - Judith Leibiger
- Department of Genetics, Institute of Biology, University of Leipzig, Talstr. 33, 04103 Leipzig, Germany, Department of Genetics of Learning and Memory, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
| | - Amira El-Keredy
- Department of Genetics, Faculty of Agriculture, Tanta University, Tanta-Kafr El-Sheikh Road, Seberbay Campus, 31527 Tanta, Egypt
| | - Bertram Gerber
- Department of Genetics of Learning and Memory, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany, Institute of Biology, Otto von Guericke University of Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany and Center for Behavioral Brain Sciences, Universitätsplatz 2, 39106 Magdeburg, Germany
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12
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Manger P. Questioning the interpretations of behavioral observations of cetaceans: Is there really support for a special intellectual status for this mammalian order? Neuroscience 2013; 250:664-96. [DOI: 10.1016/j.neuroscience.2013.07.041] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/17/2013] [Indexed: 11/26/2022]
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13
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Richardson K. The evolution of intelligent developmental systems. ADVANCES IN CHILD DEVELOPMENT AND BEHAVIOR 2013; 44:127-59. [PMID: 23834004 DOI: 10.1016/b978-0-12-397947-6.00005-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This chapter aims to understand the relations between the evolution and development of complex cognitive functions by emphasizing the context of complex, changeable environments. What evolves and develops in such contexts cannot be achieved by linear deterministic processes based on stable "codes". Rather, what is needed, even in the molecular ensembles of single-cell organisms, are "intelligent" systems with nonlinear dynamic processing, sensitive to informational structures, not just elements, in environments. This is the view emerging in recent molecular biology. The research is also constructing a new "biologic" of both evolution and development, providing a clearer rationale for transitions into more complex forms, including epigenetic, physiological, nervous, cognitive, and human sociocognitive forms. This chapter explains how these transitions form a nested hierarchical system in which the dynamics within and between levels creates emergent abilities so often underestimated or even demeaned in previous accounts, especially regarding human cognition. The implications of the view for human development in modern societies are also briefly considered.
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Giurfa M. Cognition with few neurons: higher-order learning in insects. Trends Neurosci 2013; 36:285-94. [PMID: 23375772 DOI: 10.1016/j.tins.2012.12.011] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 12/10/2012] [Accepted: 12/28/2012] [Indexed: 11/25/2022]
Abstract
Insects possess miniature brains but exhibit a sophisticated behavioral repertoire. Recent studies have reported the existence of unsuspected cognitive capabilities in various insect species that go beyond the traditionally studied framework of simple associative learning. Here, I focus on capabilities such as attentional modulation and concept learning and discuss their mechanistic bases. I analyze whether these behaviors, which appear particularly complex, can be explained on the basis of elemental associative learning and specific neural circuitries or, by contrast, require an explanatory level that goes beyond simple associative links. In doing this, I highlight experimental challenges and suggest future directions for investigating the neurobiology of higher-order learning in insects, with the goal of uncovering the basic neural architectures underlying cognitive processing.
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Affiliation(s)
- Martin Giurfa
- Université de Toulouse (UPS), Centre de Recherches sur la Cognition Animale, 31062 Toulouse cedex 9, France.
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15
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Wiederman S, O’Carroll D. Selective Attention in an Insect Visual Neuron. Curr Biol 2013; 23:156-61. [DOI: 10.1016/j.cub.2012.11.048] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 11/08/2012] [Accepted: 11/26/2012] [Indexed: 11/24/2022]
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16
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Okray Z, Hassan BA. Genetic approaches in Drosophila for the study neurodevelopmental disorders. Neuropharmacology 2012; 68:150-6. [PMID: 23067575 DOI: 10.1016/j.neuropharm.2012.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 08/31/2012] [Accepted: 09/07/2012] [Indexed: 12/16/2022]
Abstract
The fruit fly Drosophila melanogaster is one of the premier genetic model organisms used in biomedical research today owing to the extraordinary power of its genetic tool-kit. Made famous by numerous seminal discoveries of basic developmental mechanisms and behavioral genetics, the power of fruit fly genetics is becoming increasingly applied to questions directly relevant to human health. In this review we discuss how Drosophila research is applied to address major questions in neurodevelopmental disorders. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'.
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Affiliation(s)
- Zeynep Okray
- Laboratory of Neurogenetics, VIB Center for the Biology of Disease, VIB, Herestraat 49, Leuven, Belgium
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17
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Morawetz L, Spaethe J. Visual attention in a complex search task differs between honeybees and bumblebees. J Exp Biol 2012; 215:2515-23. [DOI: 10.1242/jeb.066399] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Mechanisms of spatial attention are used when the amount of gathered information exceeds processing capacity. Such mechanisms have been proposed in bees, but have not yet been experimentally demonstrated. We provide evidence that selective attention influences the foraging performance of two social bee species, the honeybee Apis mellifera and the bumblebee Bombus terrestris. Visual search tasks, originally developed for application in human psychology, were adapted for behavioural experiments on bees. We examined the impact of distracting visual information on search performance, which we measured as error rate and decision time. We found that bumblebees were significantly less affected by distracting objects than honeybees. Based on the results, we conclude that the search mechanism in honeybees is serial like, whereas in bumblebees it shows the characteristics of a restricted parallel-like search. Furthermore, the bees differed in their strategy to solve the speed–accuracy trade-off. Whereas bumblebees displayed slow but correct decision-making, honeybees exhibited fast and inaccurate decision-making. We propose two neuronal mechanisms of visual information processing that account for the different responses between honeybees and bumblebees, and we correlate species-specific features of the search behaviour to differences in habitat and life history.
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Affiliation(s)
- Linde Morawetz
- Department of Evolutionary Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Johannes Spaethe
- Department of Evolutionary Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
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18
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Brembs B. Towards a scientific concept of free will as a biological trait: spontaneous actions and decision-making in invertebrates. Proc Biol Sci 2011; 278:930-9. [PMID: 21159679 PMCID: PMC3049057 DOI: 10.1098/rspb.2010.2325] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 11/25/2010] [Indexed: 11/12/2022] Open
Abstract
Until the advent of modern neuroscience, free will used to be a theological and a metaphysical concept, debated with little reference to brain function. Today, with ever increasing understanding of neurons, circuits and cognition, this concept has become outdated and any metaphysical account of free will is rightfully rejected. The consequence is not, however, that we become mindless automata responding predictably to external stimuli. On the contrary, accumulating evidence also from brains much smaller than ours points towards a general organization of brain function that incorporates flexible decision-making on the basis of complex computations negotiating internal and external processing. The adaptive value of such an organization consists of being unpredictable for competitors, prey or predators, as well as being able to explore the hidden resource deterministic automats would never find. At the same time, this organization allows all animals to respond efficiently with tried-and-tested behaviours to predictable and reliable stimuli. As has been the case so many times in the history of neuroscience, invertebrate model systems are spearheading these research efforts. This comparatively recent evidence indicates that one common ability of most if not all brains is to choose among different behavioural options even in the absence of differences in the environment and perform genuinely novel acts. Therefore, it seems a reasonable effort for any neurobiologist to join and support a rather illustrious list of scholars who are trying to wrestle the term 'free will' from its metaphysical ancestry. The goal is to arrive at a scientific concept of free will, starting from these recently discovered processes with a strong emphasis on the neurobiological mechanisms underlying them.
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Affiliation(s)
- Björn Brembs
- Freie Universität Berlin, Institute for Biology-Neurobiology, Berlin, Germany.
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19
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Abstract
Variation in learning and memory abilities among closely related species, or even among populations of the same species, has opened research into the relationship between cognition, ecological context and the fitness costs, and benefits of learning and memory. Such research programmes have long been dominated by vertebrate studies and by the assumption of a relationship between cognitive abilities, brain size and metabolic costs. Research on these 'large brained' organisms has provided important insights into the understanding of cognitive functions and their adaptive value. In the present review, we discuss some aspects of the fitness costs of learning and memory by focusing on 'mini-brain' studies. Research on learning and memory in insects has challenged some traditional positions and is pushing the boundaries of our understanding of the evolution of learning and memory.
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Affiliation(s)
- James G Burns
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
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Mendoza-Angeles K, Hernández-Falcón J, Ramón F. Slow waves during sleep in crayfish. Origin and spread. J Exp Biol 2010; 213:2154-64. [DOI: 10.1242/jeb.038240] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Previous results show that when unrestrained crayfish sleep, the electrical activity of the brain changes from multiple spikes (frequencies above 300 Hz) on a flat baseline to continuous slow waves at a frequency of 15–20 Hz. To study the temporal organization of such activity, we developed a tethered crayfish preparation that allows us to place electrodes on visually identified regions of the brain. Recording the electrical activity of different brain areas shows that when the animal is active (awake), slow waves are present only in the central complex. However, simultaneously with the animal becoming limp (sleeping), slow waves spread first to deuto- and then to protocerebrum, suggesting that the central complex of the crayfish brain acts as the sleep generator.
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Affiliation(s)
- Karina Mendoza-Angeles
- UNAM, Facultad de Ingeniería, División de Ingeniería Eléctrica, Av Universidad 3000, Mexico, D., 04510, Mexico
| | - Jesús Hernández-Falcón
- UNAM, Facultad de Medicina, Departamento de Fisiología, Av Universidad 3000, Mexico, D., 04510, Mexico
| | - Fidel Ramón
- UNAM, Facultad de Medicina, División de Investigación, Av Universidad 3000, Mexico, D., 04510, Mexico
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Research progress on Drosophila visual cognition in China. SCIENCE CHINA-LIFE SCIENCES 2010; 53:374-384. [DOI: 10.1007/s11427-010-0073-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 01/19/2010] [Indexed: 02/07/2023]
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Abstract
It is argued that conscious emotional feelings can not be adequately explained by just particular circuits or coherent activations within the brain, as is conventionally believed; nor by activations representing environmental stimuli going to the brain. According to the model suggested herein, the limbic system responds to sensory and other inputs according to how closely they are associated with built-in rewards or punishments. It does this by (a) activating the autonomic nervous system so that it prepares the body to acquire a reward or avoid a punishment, and (b) also activating the prefrontal cortex (PFC). The PFC activations are temporally correlated with the autonomic activations and the feedback to them, so that they become identified with the autonomic attempts to acquire (a reward) or avoid (a punishment). The PFC circuit thus acquires a valence. The valence, along with arousal in a given context, underlies conscious emotional feelings. The model is related to: (a) how attention progresses along networks within working memory; (b) how a single, unified percept is formed; (c) how both value-based and cognitive-based responses are formulated; and (d) how the stream of consciousness is put together and driven forward. These concepts are integrated into a scenario of the orchestration of conscious experience and behaviour by subcortical-limbic system structures interacting with the cortex, and are shown to be consistent with much of the literature.
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Abstract
Schizophrenia is a debilitating mental illness that affects 1% of the population worldwide. Although its molecular etiology remains unclear, recent advances in human psychiatric genetics have identified a large number of candidate genetic risk factors involved in schizophrenia. Modeling the disease in genetically tractable animals is thus a challenging but increasingly important task. In this review, I discuss the potential problems and perspectives associated with modeling schizophrenia in fruit flies, and briefly review the recent studies analyzing the molecular and cellular functions of Disrupted-In-Schizophrenia-1 (DISC1) in transgenic flies.
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Affiliation(s)
- Katsuo Furukubo-Tokunaga
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennodai, Tsukuba, Japan.
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Xi W, Peng Y, Guo J, Ye Y, Zhang K, Yu F, Guo A. Mushroom bodies modulate salience-based selective fixation behavior in Drosophila. Eur J Neurosci 2008; 27:1441-51. [DOI: 10.1111/j.1460-9568.2008.06114.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Exploratory behaviour in NO-dependent cyclase mutants of Drosophila shows defects in coincident neuronal signalling. BMC Neurosci 2007; 8:65. [PMID: 17683617 PMCID: PMC1963332 DOI: 10.1186/1471-2202-8-65] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Accepted: 08/06/2007] [Indexed: 11/25/2022] Open
Abstract
Background Drosophila flies explore the environment very efficiently in order to colonize it. They explore collectively, not individually, so that when a few land on a food spot, they attract the others by signs. This behaviour leads to aggregation of individuals and optimizes the screening of mates and egg-laying on the most favourable food spots. Results Flies perform cycles of exploration/aggregation depending on the resources of the environment. This behavioural ecology constitutes an excellent model for analyzing simultaneous processing of neurosensory information. We reasoned that the decision of flies to land somewhere in order to achieve aggregation is based on simultaneous integration of signals (visual, olfactory, acoustic) during their flight. On the basis of what flies do in nature, we designed laboratory tests to analyze the phenomenon of neuronal coincidence. We screened many mutants of genes involved in neuronal metabolism and the synaptic machinery. Conclusion Mutants of NO-dependent cyclase show a specifically-marked behaviour phenotype, but on the other hand they are associated with moderate biochemical defects. We show that these mutants present errors in integrative and/or coincident processing of signals, which are not reducible to the functions of the peripheral sensory cells.
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Abstract
Previous exposure to a pattern in the visual scene can enhance subsequent recognition of that pattern in many species from honeybees to humans. However, whether previous experience with a visual feature of an object, such as color or shape, can also facilitate later recognition of that particular feature from multiple visual features is largely unknown. Visual feature extraction is the ability to select the key component from multiple visual features. Using a visual flight simulator, we designed a novel protocol for visual feature extraction to investigate the effects of previous experience on visual reinforcement learning in Drosophila. We found that, after conditioning with a visual feature of objects among combinatorial shape-color features, wild-type flies exhibited poor ability to extract the correct visual feature. However, the ability for visual feature extraction was greatly enhanced in flies trained previously with that visual feature alone. Moreover, we demonstrated that flies might possess the ability to extract the abstract category of "shape" but not a particular shape. Finally, this experience-dependent feature extraction is absent in flies with defective MBs, one of the central brain structures in Drosophila. Our results indicate that previous experience can enhance visual feature extraction in Drosophila and that MBs are required for this experience-dependent visual cognition.
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Affiliation(s)
- Yueqing Peng
- Institute of Neuroscience, Key Laboratory for Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China, and
| | - Wang Xi
- Institute of Neuroscience, Key Laboratory for Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China, and
| | - Wei Zhang
- Institute of Neuroscience, Key Laboratory for Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China, and
| | - Ke Zhang
- Institute of Neuroscience, Key Laboratory for Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- Graduate School of the Chinese Academy of Sciences, Beijing 100049, China, and
| | - Aike Guo
- Institute of Neuroscience, Key Laboratory for Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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Clarac F, Pearlstein E. Invertebrate preparations and their contribution to neurobiology in the second half of the 20th century. ACTA ACUST UNITED AC 2007; 54:113-61. [PMID: 17500093 DOI: 10.1016/j.brainresrev.2006.12.007] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This review summarized the contribution to neurobiology achieved through the use of invertebrate preparations in the second half of the 20th century. This fascinating period was preceded by pioneers who explored a wide variety of invertebrate phyla and developed various preparations appropriate for electrophysiological studies. Their work advanced general knowledge about neuronal properties (dendritic, somatic, and axonal excitability; pre- and postsynaptic mechanisms). The study of invertebrates made it possible to identify cell bodies in different ganglia, and monitor their operation in the course of behavior. In the 1970s, the details of central neural circuits in worms, molluscs, insects, and crustaceans were characterized for the first time and well before equivalent findings were made in vertebrate preparations. The concept and nature of a central pattern generator (CPG) have been studied in detail, and the stomatogastric nervous system (STNS) is a fine example, having led to many major developments since it was first examined. The final part of the review is a discussion of recent neuroethological studies that have addressed simple cognitive functions and confirmed the utility of invertebrate models. After presenting our invertebrate "mice," the worm Caenorhabditis elegans and the fruit fly Drosophila melanogaster, our conclusion, based on arguments very different from those used fifty years ago, is that invertebrate models are still essential for acquiring insight into the complexity of the brain.
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Affiliation(s)
- François Clarac
- P3M, CNRS, Université de la Méditerranée, Marseille, France.
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Nichols CD. Drosophila melanogaster neurobiology, neuropharmacology, and how the fly can inform central nervous system drug discovery. Pharmacol Ther 2006; 112:677-700. [PMID: 16935347 DOI: 10.1016/j.pharmthera.2006.05.012] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Accepted: 05/24/2006] [Indexed: 01/25/2023]
Abstract
Central nervous system (CNS) drug discovery in the post-genomic era is rapidly evolving. Older empirical methods are giving way to newer technologies that include bioinformatics, structural biology, genetics, and modern computational approaches. In the search for new medical therapies, and in particular treatments for disorders of the central nervous system, there has been increasing recognition that identification of a single biological target is unlikely to be a recipe for success; a broad perspective is required. Systems biology is one such approach, and has been increasingly recognized as a very important area of research, as it places specific molecular targets within a context of overall biochemical action. Understanding the complex interactions between the components within a given biological system that lead to modifications in output, such as changes in behavior or development, may be important avenues of discovery to identify new therapies. One avenue to drug discovery that holds tremendous potential is the use of model genetic organisms such as the fruit fly, Drosophila melanogaster. The similarity between mode of drug action, behavior, and gene response in D. melanogaster and mammalian systems, combined with the power of genetics, have recently made the fly a very attractive system to study fundamental neuropharmacological processes relevant to human diseases. The promise that the use of model organisms such as the fly offers is speed, high throughput, and dramatically reduced overall costs that together should result in an enhanced rate of discovery.
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Affiliation(s)
- Charles D Nichols
- Department of Pharmacology and Experimental Therapeutics, LSU Health Sciences Center, 1901 Perdido St., New Orleans, LA 70112, USA.
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Butler AB, Cotterill RMJ. Mammalian and avian neuroanatomy and the question of consciousness in birds. THE BIOLOGICAL BULLETIN 2006; 211:106-27. [PMID: 17062871 DOI: 10.2307/4134586] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Some birds display behavior reminiscent of the sophisticated cognition and higher levels of consciousness usually associated with mammals, including the ability to fashion tools and to learn vocal sequences. It is thus important to ask what neuroanatomical attributes these taxonomic classes have in common and whether there are nevertheless significant differences. While the underlying brain structures of birds and mammals are remarkably similar in many respects, including high brain-body ratios and many aspects of brain circuitry, the architectural arrangements of neurons, particularly in the pallium, show marked dissimilarity. The neural substrate for complex cognitive functions that are associated with higher-level consciousness in mammals and birds alike may thus be based on patterns of circuitry rather than on local architectural constraints. In contrast, the corresponding circuits in reptiles are substantially less elaborated, with some components actually lacking, and in amphibian brains, the major thalamopallial circuits involving sensory relay nuclei are conspicuously absent. On the basis of these criteria, the potential for higher-level consciousness in these taxa appears to be lower than in birds and mammals.
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Affiliation(s)
- Ann B Butler
- The Krasnow Institute for Advanced Study and Department of Psychology, George Mason University, Fairfax, Virginia 22030, USA.
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Brembs B, Hempel de Ibarra N. Different parameters support generalization and discrimination learning in Drosophila at the flight simulator. Learn Mem 2006; 13:629-37. [PMID: 17015859 PMCID: PMC1783617 DOI: 10.1101/lm.319406] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Accepted: 06/20/2006] [Indexed: 11/24/2022]
Abstract
We have used a genetically tractable model system, the fruit fly Drosophila melanogaster to study the interdependence between sensory processing and associative processing on learning performance. We investigated the influence of variations in the physical and predictive properties of color stimuli in several different operant-conditioning procedures on the subsequent learning performance. These procedures included context and stimulus generalization as well as color, compound, and conditional discrimination (colors and patterns). A surprisingly complex dependence of the learning performance on the colors' physical and predictive properties emerged, which was clarified by taking into account the fly-subjective perception of the color stimuli. Based on estimates of the stimuli's color and brightness values, we propose that the different tasks are supported by different parameters of the color stimuli; generalization occurs only if the chromaticity is sufficiently similar, whereas discrimination learning relies on brightness differences.
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Affiliation(s)
- Björn Brembs
- Institute of Biology and Neurobiology, Freie Universität Berlin, 14195 Berlin, Germany.
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Wessnitzer J, Webb B. Multimodal sensory integration in insects--towards insect brain control architectures. BIOINSPIRATION & BIOMIMETICS 2006; 1:63-75. [PMID: 17671308 DOI: 10.1088/1748-3182/1/3/001] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Although a variety of basic insect behaviours have inspired successful robot implementations, more complex capabilities in these 'simple' animals are often overlooked. By reviewing the general architecture of their nervous systems, we gain insight into how they are able to integrate behaviours, perform pattern recognition, context-dependent learning, and combine many sensory inputs in tasks such as navigation. We review in particular what is known about two specific 'higher' areas in the insect brain, the mushroom bodies and the central complex, and how they are involved in controlling an insect's behaviour. While much of the functional interpretation of this information is still speculative, it nevertheless suggests some promising new approaches to obtaining adaptive behaviour in robots.
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Affiliation(s)
- Jan Wessnitzer
- Institute of Perception, Action and Behaviour, School of Informatics, University of Edinburgh, Scotland, UK.
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Affiliation(s)
- Alan Gelperin
- Monell Chemical Senses Center, Philadelphia, Pennsylvania 19104, USA.
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Tsitolovsky LE. Protection from neuronal damage evoked by a motivational excitation is a driving force of intentional actions. ACTA ACUST UNITED AC 2005; 49:566-94. [PMID: 16269320 DOI: 10.1016/j.brainresrev.2005.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Revised: 12/16/2004] [Accepted: 02/25/2005] [Indexed: 01/13/2023]
Abstract
Motivation may be understood as an organism's subjective attitude to its current physiological state, which somehow modulates generation of actions until the organism attains an optimal state. How does this subjective attitude arise and how does it modulate generation of actions? Diverse lines of evidence suggest that elemental motivational states (hunger, thirst, fear, drug-dependence, etc.) arise as the result of metabolic disturbances and are related to transient injury, while rewards (food, water, avoidance, drugs, etc.) are associated with the recovery of specific neurons. Just as motivation and the very life of an organism depend on homeostasis, i.e., maintenance of optimum performance, so a neuron's behavior depends on neuronal (i.e., ion) homeostasis. During motivational excitation, the conventional properties of a neuron, such as maintenance of membrane potential and spike generation, are disturbed. Instrumental actions may originate as a consequence of the compensational recovery of neuronal excitability after the excitotoxic damage induced by a motivation. When the extent of neuronal actions is proportional to a metabolic disturbance, the neuron theoretically may choose a beneficial behavior even, if at each instant, it acts by chance. Homeostasis supposedly may be directed to anticipating compensation of the factors that lead to a disturbance of the homeostasis and, as a result, participates in the plasticity of motivational behavior. Following this line of thought, I suggest that voluntary actions arise from the interaction between endogenous compensational mechanisms and excitotoxic damage of specific neurons, and thus anticipate the exogenous compensation evoked by a reward.
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Affiliation(s)
- Lev E Tsitolovsky
- Department of Life Science, Bar-Ilan University, Ramat-Gan 52900, Israel.
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Abstract
Alertness and behavioral performance depend on an animal's level of arousal. In vertebrates, reinforcement and maintenance of arousal in the cortex are ensured by diffuse inputs from neurons releasing biogenic amine neuromodulators. Fruit flies similarly use dopamine for arousal control, indicating an ancient evolutionary origin of this essential feature of the functioning brain.
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Affiliation(s)
- Serge Birman
- IBDM-Developmental Biology Institute, CNRS-INSERM-Université de la Méditerranée, Marseille, France.
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