For more than a decade, we have studied the human visual cortex using functional Magnetic Resonance Imaging (fMRI). In our studies, we use advanced high-resolution neuroimaging techniques and the state-of-the-art equipment to reveal fine mesoscale neural structures that shape human behavior.
In collaboration with clinicians in Massachusetts General Hospital (MGH) and Boston Children’s Hospital (BCH), we also study the impacts of various neurodegenerative, neuropsychological and developmental disorders on visual perception and the neural mechanisms underlying them.
Functional MRI (fMRI) is a non-invasive approach to study the brain activity. Despite its exceptional capabilities in localizing neuronal responses, applications of this technique in studying fast brain activities are limited.
In Nasr et al. (2021), we introduced a new approach to assess the link between fMRI fluctuations and fast brain responses. We showed that the level of fMRI co-fluctuations, measured between the fine-scale cross-hemispheric cortical sites, varies with the spatial organization of visual stimuli – a feature encoded by gamma-band neuronal activities. In this study, we have also assessed the impact of multiple factors on the level this co-fluctuation, including the stimulus noise and location, cognitive tasks and cortical depth.