Elucidating brain imaging signals, illuminating functional principles of the visual brain
Our lab focuses on two goals. The first is to understand functional brain imaging signals, and to evaluate the degree to which they reflect the underlying neuronal activity.
The second is to elucidate the principles and processes used by the cerebral cortex to analyze visual information and to create coherent visual perception, with emphasis on understanding interactions between visual areas.
Functional brain imaging signals
Many scientists around the world study human brain activity associated with a variety of conditions and tasks. These researchers rely on non-invasive functional brain imaging methods, which measure increased blood flow to active regions in the brain.
Identical imaging methods are increasingly used for clinical diagnosis and for monitoring psychiatric and neurological disorders. The changes in blood flow are indirect measures of changes in neuronal activity. Therefore, to correctly interpret these imaging signals, it is imperative to understand the coupling of blood flow to the underlying neuronal activity.
The lab employs an integrative approach, using a combination of imaging and electrical recording techniques. These include functional Magnetic
Resonance Imaging (fMRI), optical imaging using intrinsic signals and voltage sensitive dyes, multi-channel neurophysiological recordings,
and neurophysiology simultaneously with fMRI. Together, these techniques encompass multiple levels of spatial and temporal
resolution. Brain activity signals obtained by large scale non-invasive imaging methods are compared to activity of ensembles of neurons imaged
optically, and to electrically-recorded activity obtained from groups of neurons and single neurons. The measurements are carried out while
different types of visual stimuli are projected to the eyes.