Brain areas involved in echolocation motion processing in blind echolocation experts

2012 ◽  
Vol 25 (0) ◽  
pp. 140
Author(s):  
Lore Thaler ◽  
Jennifer Milne ◽  
Stephen R. Arnott ◽  
Melvyn A. Goodale
Keyword(s):  
Visual Motion ◽  
Brain Activity ◽  
Temporal Cortex ◽  
Spatial Arrangement ◽  
Inferior Temporal Cortex ◽  
Motion Processing ◽  
Brain Areas ◽  
Area Mt ◽  
Visual Motion Processing ◽  
Source Motion

People can echolocate their distal environment by making mouth-clicks and listening to the click-echoes. In previous work that used functional magnetic resonance imaging (fMRI) we have shown that the processing of echolocation motion increases activity in posterior/inferior temporal cortex (Thaler et al., 2011). In the current study we investigated, if brain areas that are sensitive to echolocation motion in blind echolocation experts correspond to visual motion area MT+. To this end we used fMRI to measure brain activity of two early blind echolocation experts while they listened to recordings of echolocation and auditory source sounds that could be either moving or stationary, and that could be located either to the left or to the right of the listener. A whole brain analysis revealed that echo motion and source motion activated different brain areas in posterior/inferior temporal cortex. Furthermore, the relative spatial arrangement of echo and source motion areas appeared to match the relative spatial arrangement of area MT+ and source motion areas that has been reported for sighted people (Saenz et al., 2008). Furthermore, we found that brain areas that were sensitive to echolocation motion showed a larger response to echo motion presented in contra-lateral space, a response pattern typical for visual motion processing in area MT+. In their entirety the data are consistent with the idea that brain areas that process echolocation motion in blind echolocation experts correspond to area MT+.

scholarly journals White matter deficits correlate with visual motion perception impairments in dyslexic carriers of the DCDC2 genetic risk variant

2021 ◽  
Author(s):  
Daniela Perani ◽  
Paola Scifo ◽  
Guido M. Cicchini ◽  
Pasquale Della Rosa ◽  
Chiara Banfi ◽  
...  
Keyword(s):  
White Matter ◽  
Motion Perception ◽  
Visual Motion ◽  
Visual Analysis ◽  
Temporal Cortex ◽  
Inferior Temporal Cortex ◽  
Motion Processing ◽  
Motion Direction ◽  
Risk Variant ◽  
Visual Motion Processing

AbstractMotion perception deficits in dyslexia show a large intersubjective variability, partly reflecting genetic factors influencing brain architecture development. In previous work, we have demonstrated that dyslexic carriers of a mutation of the DCDC2 gene have a very strong impairment in motion perception. In the present study, we investigated structural white matter alterations associated with the poor motion perception in a cohort of twenty dyslexics with a subgroup carrying the DCDC2 gene deletion (DCDC2d+) and a subgroup without the risk variant (DCDC2d–). We observed significant deficits in motion contrast sensitivity and in motion direction discrimination accuracy at high contrast, stronger in the DCDC2d+ group. Both motion perception impairments correlated significantly with the fractional anisotropy in posterior ventral and dorsal tracts, including early visual pathways both along the optic radiation and in proximity of occipital cortex, MT and VWFA. However, the DCDC2d+ group showed stronger correlations between FA and motion perception impairments than the DCDC2d– group in early visual white matter bundles, including the optic radiations, and in ventral pathways located in the left inferior temporal cortex. Our results suggest that the DCDC2d+ group experiences higher vulnerability in visual motion processing even at early stages of visual analysis, which might represent a specific feature associated with the genotype and provide further neurobiological support to the visual-motion deficit account of dyslexia in a specific subpopulation.

Neural correlates of motion processing through echolocation, source hearing, and vision in blind echolocation experts and sighted echolocation novices

2014 ◽  
Vol 111 (1) ◽  
pp. 112-127 ◽  
Author(s):  
L. Thaler ◽  
J. L. Milne ◽  
S. R. Arnott ◽  
D. Kish ◽  
M. A. Goodale
Keyword(s):  
Visual Motion ◽  
Brain Activity ◽  
Region Of Interest ◽  
Occipital Cortex ◽  
Neural Substrates ◽  
Motion Processing ◽  
Planum Temporale ◽  
Show Evidence ◽  
Visual Cortical ◽  
Source Motion

We have shown in previous research (Thaler L, Arnott SR, Goodale MA. PLoS One 6: e20162, 2011) that motion processing through echolocation activates temporal-occipital cortex in blind echolocation experts. Here we investigated how neural substrates of echo-motion are related to neural substrates of auditory source-motion and visual-motion. Three blind echolocation experts and twelve sighted echolocation novices underwent functional MRI scanning while they listened to binaural recordings of moving or stationary echolocation or auditory source sounds located either in left or right space. Sighted participants' brain activity was also measured while they viewed moving or stationary visual stimuli. For each of the three modalities separately (echo, source, vision), we then identified motion-sensitive areas in temporal-occipital cortex and in the planum temporale. We then used a region of interest (ROI) analysis to investigate cross-modal responses, as well as laterality effects. In both sighted novices and blind experts, we found that temporal-occipital source-motion ROIs did not respond to echo-motion, and echo-motion ROIs did not respond to source-motion. This double-dissociation was absent in planum temporale ROIs. Furthermore, temporal-occipital echo-motion ROIs in blind, but not sighted, participants showed evidence for contralateral motion preference. Temporal-occipital source-motion ROIs did not show evidence for contralateral preference in either blind or sighted participants. Our data suggest a functional segregation of processing of auditory source-motion and echo-motion in human temporal-occipital cortex. Furthermore, the data suggest that the echo-motion response in blind experts may represent a reorganization rather than exaggeration of response observed in sighted novices. There is the possibility that this reorganization involves the recruitment of “visual” cortical areas.

Cortical Dynamics of Anticipatory Mechanisms in Interception: A Neuromagnetic Study

2008 ◽  
Vol 20 (10) ◽  
pp. 1827-1838 ◽  
Author(s):  
Patrice Senot ◽  
Sylvain Baillet ◽  
Bernard Renault ◽  
Alain Berthoz
Keyword(s):  
Visual Motion ◽  
Brain Activity ◽  
Motion Processing ◽  
Experimental Conditions ◽  
Visuomotor Task ◽  
Visual Motion Processing ◽  
Spatio Temporal ◽  
Cortical Regions ◽  
Ball Trajectory ◽  
Free Falling

Humans demonstrate an amazing ability for intercepting and catching moving targets, most noticeably in fast-speed ball games. However, the few studies exploring the neural bases of interception in humans and the classical studies on visual motion processing and visuomotor interactions have reported rather long latencies of cortical activations that cannot explain the performances observed in most natural interceptive actions. The aim of our experiment was twofold: (1) describe the spatio-temporal unfolding of cortical activations involved in catching a moving target and (2) provide evidence that fast cortical responses can be elicited by a visuomotor task with high temporal constraints and decide if these responses are task or stimulus dependent. Neuromagnetic brain activity was recorded with whole-head coverage while subjects were asked to catch a free-falling ball or simply pay attention to the ball trajectory. A fast, likely stimulus-dependent, propagation of neural activity was observed along the dorsal visual pathway in both tasks. Evaluation of latencies of activations in the main cortical regions involved in the tasks revealed that this entire network of regions was activated within 40 msec. Moreover, comparison of experimental conditions revealed similar patterns of activation except in contralateral sensorimotor regions where common and catch-specific activations were differentiated.

scholarly journals Visual Motion Processing by Neurons in Area MT of Macaque Monkeys with Experimental Amblyopia

2010 ◽  
Vol 30 (36) ◽  
pp. 12198-12209 ◽  
Author(s):  
Y. El-Shamayleh ◽  
L. Kiorpes ◽  
A. Kohn ◽  
J. A. Movshon
Keyword(s):  
Visual Motion ◽  
Motion Processing ◽  
Area Mt ◽  
Macaque Monkeys ◽  
Visual Motion Processing

Pursuit and optokinetic deficits following chemical lesions of cortical areas MT and MST

1988 ◽  
Vol 60 (3) ◽  
pp. 940-965 ◽  
Author(s):  
M. R. Dursteler ◽  
R. H. Wurtz
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Visual Motion ◽  
Ibotenic Acid ◽  
Motion Processing ◽  
Temporal Area ◽  
Target Speed ◽  
Pursuit Eye Movements ◽  
Medial Superior Temporal ◽  
Visual Motion Processing

1. Previous experiments have shown that punctate chemical lesions within the middle temporal area (MT) of the superior temporal sulcus (STS) produce deficits in the initiation and maintenance of pursuit eye movements (10, 34). The present experiments were designed to test the effect of such chemical lesions in an area within the STS to which MT projects, the medial superior temporal area (MST). 2. We injected ibotenic acid into localized regions of MST, and we observed two deficits in pursuit eye movements, a retinotopic deficit and a directional deficit. 3. The retinotopic deficit in pursuit initiation was characterized by the monkey's inability to match eye speed to target speed or to adjust the amplitude of the saccade made to acquire the target to compensate for target motion. This deficit was related to the initiation of pursuit to targets moving in any direction in the visual field contralateral to the side of the brain with the lesion. This deficit was similar to the deficit we found following damage to extrafoveal MT except that the affected area of the visual field frequently extended throughout the entire contralateral visual field tested. 4. The directional deficit in pursuit maintenance was characterized by a failure to match eye speed to target speed once the fovea had been brought near the moving target. This deficit occurred only when the target was moving toward the side of the lesion, regardless of whether the target began to move in the ipsilateral or contralateral visual field. There was no deficit in the amplitude of saccades made to acquire the target, or in the amplitude of the catch-up saccades made to compensate for the slowed pursuit. The directional deficit is similar to the one we described previously following chemical lesions of the foveal representation in the STS. 5. Retinotopic deficits resulted from any of our injections in MST. Directional deficits resulted from lesions limited to subregions within MST, particularly lesions that invaded the floor of the STS and the posterior bank of the STS just lateral to MT. Extensive damage to the densely myelinated area of the anterior bank or to the posterior parietal area on the dorsal lip of the anterior bank produced minimal directional deficits. 6. We conclude that damage to visual motion processing in MST underlies the retinotopic pursuit deficit just as it does in MT. MST appears to be a sequential step in visual motion processing that occurs before all of the visual motion information is transmitted to the brainstem areas related to pursuit.(ABSTRACT TRUNCATED AT 400 WORDS)

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