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Top-down modulation of visual cortical processing after transient congenital blindness
Maria J S Guerreiro1, Ramesh Kekunnaya2, Brigitte Röder3
1Biological Psychology and Neuropsychology, Institute for Psychology, University of Hamburg, Von-Melle-Park 11, D-20146, Hamburg, Germany; Biological Psychology, Department of Psychology, School of Medicine and Health Sciences, Carl von Ossietzky University of Oldenburg, Ammerländer Heerstr. 114-118, 26111, Oldenburg, Germany.
Neuropsychologia
|August 5, 2022
Summary
Early visual deprivation impacts motion processing in the brain but not attentional modulation. The visual cortex
Area of Science:
- Neuroscience
- Visual Perception
- Brain Development
Background:
- Early visual experience is crucial for developing visual and multisensory functions.
- The impact of early visual deprivation on functional brain organization is not well understood.
- Attentional modulation of visual processing is key to how the brain prioritizes information.
Purpose of the Study:
- To investigate how early visual deprivation affects top-down attentional modulation in the occipito-temporal cortex.
- To determine if early visual deprivation alters the response of the motion-selective area hMT to moving visual stimuli.
- To compare brain activity in cataract-reversal participants and normally sighted controls.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used to compare brain activity.
- Cortical responses in the motion-sensitive area hMT and the fusiform face area (FFA) were analyzed.
- Participants viewed moving and stationary face stimuli, varying in task relevance.
Main Results:
- Both groups showed increased responses in area hMT to moving stimuli, but this effect was reduced in the cataract-reversal group.
- Task relevance significantly enhanced responses in area hMT and FFA for both groups, with no group differences.
- Early visual deprivation appears to partially disrupt the functional specialization of area hMT for motion processing.
Conclusions:
- Top-down attentional modulation of visual processing in area hMT and FFA is independent of early visual experience.
- Early visual deprivation can partially impair the brain's motion processing capabilities, specifically in area hMT.
- The findings highlight the critical role of early visual input in establishing specialized visual functions.
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