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Takami A, Kawajiri T, Komiyama T, Aoyama C, Shimegi S. Transcranial static magnetic field stimulation over hMT+ inhibits visual motion discriminability. Sci Rep 2024; 14:1109. [PMID: 38212348 PMCID: PMC10784584 DOI: 10.1038/s41598-023-51097-x] [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: 09/26/2023] [Accepted: 12/30/2023] [Indexed: 01/13/2024] Open
Abstract
Visuomotor performance acting on a moving target is fundamentally based on visual motion discriminability, and its neural basis is presumed to be human MT (hMT+), a motion vision center of the dorsal visual pathway. In this study, we investigated whether and how the accuracy and speed of motion discrimination are affected by applying transcranial static magnetic field stimulation (tSMS) to hMT+, which reduces cortical excitability. Sixteen participants performed a motion direction discrimination (MDD) task using a random dot kinematogram before (Pre-test) and during (During-test) application of the tSMS over left hMT+. The correct rate of the MDD task was significantly lower in the During-test compared to the Pre-test, an effect not seen with the sham condition. The inhibition effects were observed only for the right visual field corresponding to hMT+ in the stimulated hemisphere. On the other hand, no modulatory effect of tSMS was observed in the reaction time. We, therefore, demonstrated the inhibitory effect of tSMS on the left hMT+ impairs the accuracy but not the speed of motion information processing in the contralateral visual field.
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Affiliation(s)
- Ayaka Takami
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka, Japan
- Center for Education in Liberal Arts and Sciences, Osaka University, Toyonaka, Osaka, Japan
| | - Toshitaka Kawajiri
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka, Japan
| | - Takaaki Komiyama
- Center for Education in Liberal Arts and Sciences, Osaka University, Toyonaka, Osaka, Japan
| | - Chisa Aoyama
- Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan
| | - Satoshi Shimegi
- Graduate School of Frontier Biosciences, Osaka University, Toyonaka, Osaka, Japan.
- Center for Education in Liberal Arts and Sciences, Osaka University, Toyonaka, Osaka, Japan.
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2
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Rowe EG, Zhang Y, Garrido MI. Evidence for adaptive myelination of subcortical shortcuts for visual motion perception in healthy adults. Hum Brain Mapp 2023; 44:5641-5654. [PMID: 37608684 PMCID: PMC10619379 DOI: 10.1002/hbm.26467] [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: 02/15/2023] [Revised: 05/27/2023] [Accepted: 08/08/2023] [Indexed: 08/24/2023] Open
Abstract
Conscious visual motion information follows a cortical pathway from the retina to the lateral geniculate nucleus (LGN) and on to the primary visual cortex (V1) before arriving at the middle temporal visual area (MT/V5). Alternative subcortical pathways that bypass V1 are thought to convey unconscious visual information. One flows from the retina to the pulvinar (PUL) and on to medial temporal visual area (MT); while the other directly connects the LGN to MT. Evidence for these pathways comes from non-human primates and modest-sized studies in humans with brain lesions. Thus, the aim of the current study was to reconstruct these pathways in a large sample of neurotypical individuals and to determine the degree to which these pathways are myelinated, suggesting information flow is rapid. We used the publicly available 7T (N = 98; 'discovery') and 3T (N = 381; 'validation') diffusion magnetic resonance imaging datasets from the Human Connectome Project to reconstruct the PUL-MT (including all subcompartments of the PUL) and LGN-MT pathways. We found more fibre tracts with greater density in the left hemisphere. Although the left PUL-MT path was denser, the bilateral LGN-MT tracts were more heavily myelinated, suggesting faster signal transduction. We suggest that this apparent discrepancy may be due to 'adaptive myelination' caused by more frequent use of the LGN-MT pathway that leads to greater myelination and faster overall signal transmission.
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Affiliation(s)
- Elise G. Rowe
- Melbourne School of Psychological SciencesThe University of MelbourneParkvilleVictoriaAustralia
| | - Yubing Zhang
- Melbourne School of Psychological SciencesThe University of MelbourneParkvilleVictoriaAustralia
| | - Marta I. Garrido
- Melbourne School of Psychological SciencesThe University of MelbourneParkvilleVictoriaAustralia
- Graeme Clark Institute for Biomedical EngineeringThe University of MelbourneParkvilleVictoriaAustralia
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3
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Van Swol JM, Thompson EB, Joffe JA, Nguyen SA, Berman EL. Akinetopsia: A Systematic Review. J Neuroophthalmol 2023:00041327-990000000-00496. [PMID: 37938052 DOI: 10.1097/wno.0000000000002032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
ABSTRACT Selective motion blindness, also known as akinetopsia, is infrequently reported in the literature. Hence, little is known about the condition including its causes, time course, pathophysiology, and current diagnostic methods. In this investigation, we comprehensively surveyed the literature using a systematic review to identify each reported case of the condition. The purpose of this study was to provide an exhaustive catalog of every published occurrence to date to identify and discuss trends, commonalities, and differences among them. Our results revealed distinct characteristics for the various etiologies of this phenomenon in addition to a shared pathophysiologic pathway among them.
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Affiliation(s)
- Joshua M Van Swol
- Department of Ophthalmology (JMVS), Texas Tech Health Sciences Center, Lubbock, Texas; College of Medicine (EBT), Medical University of South Carolina, Charleston, South Carolina; College of Medicine (JAJ), University of South Carolina School of Medicine, Greenville, South Carolina; and Departments of Otolaryngology-Head and Neck Surgery (SAN) and Ophthalmology-Neuro-Ophthalmology (EB), Medical University of South Carolina, Charleston, South Carolina
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Yan S, Zhang Y, Yin X, Chen J, Zhu Z, Jin H, Li H, Yin J, Jiang Y. Alterations in white matter integrity and network topological properties are associated with a decrease in global motion perception in older adults. Front Aging Neurosci 2023; 15:1045263. [PMID: 36967826 PMCID: PMC10034108 DOI: 10.3389/fnagi.2023.1045263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 02/20/2023] [Indexed: 03/11/2023] Open
Abstract
Previous studies have mainly explored the effects of structural and functional aging of cortical regions on global motion sensitivity in older adults, but none have explored the structural white matter (WM) substrates underlying the age-related decrease in global motion perception (GMP). In this study, random dot kinematogram and diffusion tensor imaging were used to investigate the effects of age-related reductions in WM fiber integrity and connectivity across various regions on GMP. We recruited 106 younger adults and 94 older adults and utilized both tract-based spatial statistics analysis and graph theoretical analysis to comprehensively investigate group differences in WM microstructural and network connections between older and younger adults at the microscopic and macroscopic levels. Moreover, partial correlation analysis was used to explore the relationship between alterations in WM and the age-related decrease in GMP. The results showed that decreased GMP in older adults was related to decreased fractional anisotropy (FA) of the inferior frontal-occipital fasciculus, inferior longitudinal fasciculus, anterior thalamic radiation, superior longitudinal fasciculus, and cingulum cingulate gyrus. Decreased global efficiency of the WM structural network and increased characteristic path length were closely associated with decreased global motion sensitivity. These results suggest that the reduced GMP in older adults may stem from reduced WM integrity in specific regions of WM fiber tracts as well as decreased efficiency of information integration and communication between distant cortical regions, supporting the “disconnection hypothesis” of cognitive aging.
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Affiliation(s)
- Shizhen Yan
- Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Yuping Zhang
- Medicine School of Rehabilitation, Henan University of Chinese Medicine, Zhengzhou, China
| | - Xiaojuan Yin
- Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Juntao Chen
- Faculty of Psychology, Tianjin Normal University, Tianjin, China
| | - Ziliang Zhu
- State Key Laboratory for Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
| | - Hua Jin
- Faculty of Psychology, Tianjin Normal University, Tianjin, China
- Key Research Base of Humanities and Social Sciences of the Ministry of Education, Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
- *Correspondence: Hua Jin,
| | - Han Li
- The First Central Clinical College of Tianjin Medical University, Tianjin, China
| | - Jianzhong Yin
- Department of Radiology, People’s Hospital of Haikou, Haikou, China
| | - Yunpeng Jiang
- Faculty of Psychology, Tianjin Normal University, Tianjin, China
- Key Research Base of Humanities and Social Sciences of the Ministry of Education, Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China
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5
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Suzuki Y, Atmaca S, Laeng B. The lateralized flash-lag illusion: A psychophysical and pupillometry study. Brain Cogn 2023; 166:105956. [PMID: 36736146 DOI: 10.1016/j.bandc.2023.105956] [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: 09/12/2022] [Revised: 01/21/2023] [Accepted: 01/22/2023] [Indexed: 02/04/2023]
Abstract
The flash-lag illusion (FLI) is a visual phenomenon where a flashed object, either co-localized or in physical alignment with another continuously moving object, is perceived to lag behind the path of the moving object. In the present study, we reveal an anisotropy of the FLI between the lateral visual fields that was expressed psychophysically as different points of subjective equality, depending on the hemifield in which the stimuli appeared. Specifically, the study confirmed that, as seen in two previous studies, the FLI was significantly larger in the left visual field (LVF) than in the right (RVF). In addition, pupil dilations were larger in the RVF than in the LVF as well as returning to baseline levels more rapidly in the LVF. We interpret these findings as converging on revealing more efficient spatial and attentional processing and, in turn, extrapolation of motion in the LVF/right hemisphere than in the RVF/left hemisphere.
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Affiliation(s)
- Yuta Suzuki
- NTT Communication Science Laboratories, NTT Corporation, Kanagawa 243-0198, Japan.
| | - Sumeyya Atmaca
- Department of Psychology, University of Oslo, 0373 Oslo, Norway
| | - Bruno Laeng
- Department of Psychology, University of Oslo, 0373 Oslo, Norway; RITMO Centre for Interdisciplinary Studies in Rhythm, Time and Motion, University of Oslo, Oslo, Norway
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Wilkerson GB, Colston MA, Acocello SN, Hogg JA, Carlson LM. Subtle impairments of perceptual-motor function and well-being are detectable among military cadets and college athletes with self-reported history of concussion. Front Sports Act Living 2023; 5:1046572. [PMID: 36761780 PMCID: PMC9905443 DOI: 10.3389/fspor.2023.1046572] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 01/03/2023] [Indexed: 01/26/2023] Open
Abstract
Introduction A lack of obvious long-term effects of concussion on standard clinical measures of behavioral performance capabilities does not preclude the existence of subtle neural processing impairments that appear to be linked to elevated risk for subsequent concussion occurrence, and which may be associated with greater susceptibility to progressive neurodegenerative processes. The purpose of this observational cohort study was to assess virtual reality motor response variability and survey responses as possible indicators of suboptimal brain function among military cadets and college athletes with self-reported history of concussion (HxC). Methods The cohort comprised 75 college students (20.7 ± 2.1 years): 39 Reserve Officer Training Corp (ROTC) military cadets (10 female), 16 football players, and 20 wrestlers; HxC self-reported by 20 (29.2 ± 27.1 months prior, range: 3-96). A virtual reality (VR) test involving 40 lunging/reaching responses to horizontally moving dots (filled/congruent: same direction; open/incongruent: opposite direction) was administered, along with the Sport Fitness and Wellness Index (SFWI) survey. VR Dispersion (standard deviation of 12 T-scores for neck, upper extremity, and lower extremity responses to congruent vs. incongruent stimuli originating from central vs. peripheral locations) and SFWI response patterns were the primary outcomes of interest. Results Logistic regression modeling of VR Dispersion (range: 1.5-21.8), SFWI (range: 44-100), and an interaction between them provided 81% HxC classification accuracy (Model χ 2[2] = 26.03, p < .001; Hosmer & Lemeshow χ 2[8] = 1.86, p = .967; Nagelkerke R 2 = .427; Area Under Curve = .841, 95% CI: .734, .948). Binary modeling that included VR Dispersion ≥3.2 and SFWI ≤86 demonstrated 75% sensitivity and 86% specificity with both factors positive (Odds Ratio = 17.6, 95% CI: 5.0, 62.1). Discussion/Conclusion Detection of subtle indicators of altered brain processes that might otherwise remain unrecognized is clearly important for both short-term and long-term clinical management of concussion. Inconsistency among neck, upper extremity, and lower extremity responses to different types of moving visual stimuli, along with survey responses suggesting suboptimal well-being, merit further investigation as possible clinical indicators of persisting effects of concussion that might prove to be modifiable.
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Affiliation(s)
- Gary B Wilkerson
- Department of Health and Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN, United States
| | - Marisa A Colston
- Department of Health and Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN, United States
| | - Shellie N Acocello
- Department of Health and Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN, United States
| | - Jennifer A Hogg
- Department of Health and Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN, United States
| | - Lynette M Carlson
- Department of Health and Human Performance, University of Tennessee at Chattanooga, Chattanooga, TN, United States
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7
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Butler CR, Rhodes E, Blackmore J, Cheng X, Peach RL, Veldsman M, Sheerin F, Cleveland RO. Transcranial ultrasound stimulation to human middle temporal complex improves visual motion detection and modulates electrophysiological responses. Brain Stimul 2022; 15:1236-1245. [PMID: 36067978 DOI: 10.1016/j.brs.2022.08.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Transcranial ultrasound stimulation (TUS) holds promise as a novel technology for non-invasive neuromodulation, with greater spatial precision than other available methods and the ability to target deep brain structures. However, its safety and efficacy for behavioural and electrophysiological modulation remains controversial and it is not yet clear whether it can be used to manipulate the neural mechanisms supporting higher cognitive function in humans. Moreover, concerns have been raised about a potential TUS-induced auditory confound. OBJECTIVES We aimed to investigate whether TUS can be used to modulate higher-order visual function in humans in an anatomically-specific way whilst controlling for auditory confounds. METHODS We used participant-specific skull maps, functional localisation of brain targets, acoustic modelling and neuronavigation to guide TUS delivery to human visual motion processing cortex (hMT+) whilst participants performed a visual motion detection task. We compared the effects of hMT+ stimulation with sham and control site stimulation and examined EEG data for modulation of task-specific event-related potentials. An auditory mask was applied which prevented participants from distinguishing between stimulation and sham trials. RESULTS Compared with sham and control site stimulation, TUS to hMT+ improved accuracy and reduced response times of visual motion detection. TUS also led to modulation of the task-specific event-related EEG potential. The amplitude of this modulation correlated with the performance benefit induced by TUS. No pathological changes were observed comparing structural MRI obtained before and after stimulation. CONCLUSIONS The results demonstrate for the first time the precision, efficacy and safety of TUS for stimulation of higher-order cortex and cognitive function in humans whilst controlling for auditory confounds.
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Affiliation(s)
- Christopher R Butler
- Department of Brain Sciences, Imperial College London, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, UK.
| | - Edward Rhodes
- Department of Brain Sciences, Imperial College London, UK; UK Dementia Research Institute, Imperial College London, UK
| | | | - Xinghao Cheng
- Institute of Biomedical Engineering, University of Oxford, UK
| | - Robert L Peach
- Department of Brain Sciences, Imperial College London, UK; Department of Neurology, University Hospital of Würzburg, Germany
| | | | - Fintan Sheerin
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
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8
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Wang W, Lei X, Gong W, Liang K, Chen L. Facilitation and inhibition effects of anodal and cathodal tDCS over areas MT+ on the flash-lag effect. J Neurophysiol 2022; 128:239-248. [PMID: 35766444 DOI: 10.1152/jn.00091.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The perceived position of a moving object in vision entails an accumulation of neural signals over space and time. Due to neural signal transmission delays, the visual system can not acquire immediate information about the moving object's position. Although physiological and psychophysical studies on the flash-lag effect (FLE), a moving object is perceived ahead of a flash even they are aligned at the same location, have shown that the visual system develops the mechanisms of predicting the object's location to compensate for the neural delays, the neural mechanisms of motion-induced location prediction are not still understood well. Here, we investigated the role of neural activity changes in areas MT+ (specialized for motion processing) and the potential contralateral processing preference of MT+ in modulating the FLE. Using transcranial direct current stimulations (tDCS) over the left and right MT+ between pre-and post-tests of the FLE in different motion directions, we measured the effects of tDCS on the FLE. The results found that anodal and cathodal tDCS enhanced and reduced the FLE with the moving object heading to but not deviating from the side of the brain stimulated, respectively, compared to sham tDCS. These findings suggest a causal role of area MT+ in motion-induced location prediction, which may involve the integration of position information.
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Affiliation(s)
- Wu Wang
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| | - Xiao Lei
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Wenxiao Gong
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| | - Kun Liang
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
| | - Lihan Chen
- School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China
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9
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Whitton S, Kim JM, Scurry AN, Otto S, Zhuang X, Cordes D, Jiang F. Multisensory temporal processing in early deaf. Neuropsychologia 2021; 163:108069. [PMID: 34715119 PMCID: PMC8653765 DOI: 10.1016/j.neuropsychologia.2021.108069] [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: 12/22/2020] [Revised: 08/01/2021] [Accepted: 10/21/2021] [Indexed: 10/20/2022]
Abstract
Navigating the world relies on understanding progressive sequences of multisensory events across time. Early deaf (ED) individuals are more precise in visual detection of space and motion than their normal hearing (NH) counterparts. However, whether ED individuals show altered multisensory temporal processing abilities is less clear. According to the connectome model, brain development depends on experience, and therefore the lack of audition may affect how the brain responds to remaining senses and how they are functionally connected. We used a temporal order judgment (TOJ) task to examine multisensory (visuotactile) temporal processing in ED and NH groups. We quantified BOLD responses and functional connectivity (FC) in both groups. ED and NH groups performed similarly for the visuotactile TOJ task. Bilateral posterior superior temporal sulcus (pSTS) BOLD responses during the TOJ task were significantly larger in the ED group than in NH. Using anatomically defined pSTS seeds, our FC analysis revealed stronger somatomotor and weaker visual regional connections in the ED group than in NH during the TOJ task. These results suggest that a lack of auditory input might alter the balance of tactile and visual area FC with pSTS when a multisensory temporal task is involved.
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Affiliation(s)
- Simon Whitton
- Department of Psychology, University of Nevada, Reno, USA.
| | - Jung Min Kim
- Department of Psychology, University of Nevada, Reno, USA
| | | | - Stephanie Otto
- Department of Psychology, University of Nevada, Reno, USA
| | - Xiaowei Zhuang
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, USA
| | - Dietmar Cordes
- Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, USA
| | - Fang Jiang
- Department of Psychology, University of Nevada, Reno, USA
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10
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V5/MT+ modulates spatio-temporal integration differently across and within hemifields: Causal evidence from TMS. Neuropsychologia 2021; 161:107995. [PMID: 34425143 DOI: 10.1016/j.neuropsychologia.2021.107995] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/09/2021] [Accepted: 08/17/2021] [Indexed: 11/22/2022]
Abstract
It is unclear how the brain reaches the correct balance between temporal and spatial processing necessary to perceive motion across space. Here, we tested whether visual motion area V5/MT + plays a causal role in Ternus illusion. Ternus displays can be perceived as showing either group motion or element motion and are empirically useful for dissociating temporal and spatial grouping across visual fields. Online single-pulse TMS was applied to observers during the presentation of Ternus displays, either within or across hemifields, over left V5/MT + or, respectively, a control site in the left somatosensory cortex, or an additional 'Sham' control condition. In the cross-hemifields condition, observers perceived more element motion with TMS over left V5/MT + than in either control condition. By contrast, in the within-hemifield condition, observers reported more group motion after left V5/MT + TMS. Our findings demonstrate a causal role of left V5/MT+ in the spatio-temporal grouping of Ternus apparent motion, and in maintaining the balance of spatio-temporal processing both within and across individual hemifields.
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11
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Chakraborty A, Tran TT, Silva AE, Giaschi D, Thompson B. Continuous theta burst TMS of area MT+ impairs attentive motion tracking. Eur J Neurosci 2021; 54:7289-7300. [PMID: 34591329 DOI: 10.1111/ejn.15480] [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: 02/09/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 11/28/2022]
Abstract
Attentive motion tracking deficits measured using multiple object tracking (MOT) tasks have been identified in a number of neurodevelopmental disorders such as amblyopia and autism. These deficits are often attributed to the abnormal development of high-level attentional networks. However, neuroimaging evidence from amblyopia suggests that reduced MOT performance can be explained by impaired function in motion-sensitive area MT+ alone. To test the hypothesis that a subtle disruption of MT+ function could cause MOT impairment, we assessed whether continuous theta burst stimulation (cTBS) of MT+ influenced MOT task accuracy in individuals with normal vision. The MOT stimulus consisted of four target and four distractor dots and was presented at ±10° eccentricity (right/left hemifield). fMRI-guided cTBS was applied to left MT+. Participants (n = 13, age: 27 ± 3) attended separate active and sham cTBS sessions where the MOT task was completed before, 5-min post- and 30-min post-cTBS. Active cTBS significantly impaired MOT task accuracy relative to baseline for the right (stimulated) hemifield 5-min (10 ± 2% reduction) and 30-min (14 ± 3% reduction) post-stimulation. No impairment occurred within the left (control) hemifield after active cTBS or for either hemifield after sham cTBS. These results highlight the importance of lower level motion processing for MOT, suggesting that a minor disruption of MT+ function alone is sufficient to cause a deficit in MOT performance.
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Affiliation(s)
- Arijit Chakraborty
- School of Optometry and Vision Science, Faculty of Science, University of Waterloo, Waterloo, Ontario, Canada.,Chicago College of Optometry, Midwestern University, Downers Grove, Illinois, USA
| | - Tiffany T Tran
- School of Optometry and Vision Science, Faculty of Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Andrew E Silva
- School of Optometry and Vision Science, Faculty of Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Deborah Giaschi
- Department of Ophthalmology and Visual Sciences, University of British Columbia/B.C. Children's Hospital, Vancouver, British Columbia, Canada
| | - Benjamin Thompson
- School of Optometry and Vision Science, Faculty of Science, University of Waterloo, Waterloo, Ontario, Canada.,Centre for Eye and Vision Research (CEVR), Hong Kong, China.,Liggins Institute, University of Auckland, Auckland, New Zealand
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12
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Schmitt C, Baltaretu BR, Crawford JD, Bremmer F. A Causal Role of Area hMST for Self-Motion Perception in Humans. Cereb Cortex Commun 2020; 1:tgaa042. [PMID: 34296111 PMCID: PMC8152865 DOI: 10.1093/texcom/tgaa042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/12/2020] [Accepted: 07/22/2020] [Indexed: 02/04/2023] Open
Abstract
Previous studies in the macaque monkey have provided clear causal evidence for an involvement of the medial-superior-temporal area (MST) in the perception of self-motion. These studies also revealed an overrepresentation of contraversive heading. Human imaging studies have identified a functional equivalent (hMST) of macaque area MST. Yet, causal evidence of hMST in heading perception is lacking. We employed neuronavigated transcranial magnetic stimulation (TMS) to test for such a causal relationship. We expected TMS over hMST to induce increased perceptual variance (i.e., impaired precision), while leaving mean heading perception (accuracy) unaffected. We presented 8 human participants with an optic flow stimulus simulating forward self-motion across a ground plane in one of 3 directions. Participants indicated perceived heading. In 57% of the trials, TMS pulses were applied, temporally centered on self-motion onset. TMS stimulation site was either right-hemisphere hMST, identified by a functional magnetic resonance imaging (fMRI) localizer, or a control-area, just outside the fMRI localizer activation. As predicted, TMS over area hMST, but not over the control-area, increased response variance of perceived heading as compared with noTMS stimulation trials. As hypothesized, this effect was strongest for contraversive self-motion. These data provide a first causal evidence for a critical role of hMST in visually guided navigation.
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Affiliation(s)
- Constanze Schmitt
- Department of Neurophysics, University of Marburg, Marburg, Germany.,Center for Mind, Brain and Behavior-CMBB, University of Marburg and Justus-Liebig-University Giessen, Germany.,International Research Training Group 1901: The Brain in Action
| | - Bianca R Baltaretu
- International Research Training Group 1901: The Brain in Action.,Centre for Vision Research and Vision: Science to Applications (VISTA) Program, York University, Toronto, Ontario, Canada.,Department of Biology, York University, Toronto, Ontario, Canada
| | - J Douglas Crawford
- International Research Training Group 1901: The Brain in Action.,Centre for Vision Research and Vision: Science to Applications (VISTA) Program, York University, Toronto, Ontario, Canada.,Departments of Psychology, Biology, Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Frank Bremmer
- Department of Neurophysics, University of Marburg, Marburg, Germany.,Center for Mind, Brain and Behavior-CMBB, University of Marburg and Justus-Liebig-University Giessen, Germany.,International Research Training Group 1901: The Brain in Action
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