Basavaraju G. Sanganahalli1, Peter Herman1,2, Christopher J. Bailey3, Douglas L. Rothman1,4, Fahmeed Hyder1,4
1Diagnostic Radiology, Yale University, New Haven, CT, USA; 2Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, Budapest, CT, Hungary; 3CFIN, Aarhus University, Aarhus, Denmark; 4Biomedical Engineering, Yale University, New Haven, CT, USA
Current understanding about BOLD signal and the underlying neurophysiology is based predominantly on functions of the cerebral cortex. BOLD activations of subcortical regions, in contrast, are hard to detect because of low sensitivity and/or difficult access. The goal of the present work was to study subcortical mechanisms underlying dispersed cortical activations during sensory stimulation in rat brain by fMRI. Our results demonstrate reproducible thalamus and superior colliculus activity during forepaw, whisker, and visual stimuli in anesthetized rats. These experiments should provide insights into understudied interactions between cortical and subcortical areas and provide a mechanistic basis to understand multisensory integration.