Most of our understanding of the human visual system comes from comparison with experimental data, especially single-cell data, obtained in monkeys. The problem has been that one has to compare results obtained not only in different species but also with different techniques. A considerable advance could be made if one could compare the functional imaging results in human to those obtained with the same technique in monkeys and then in a second step compare within the same species functional imaging data with single-cell or other experimental data. To that end one needs functional magnetic resonance imaging (fMRI) in the awake, behaving monkey.

The overall aim is to perfect the monkey fMRI technique already in place in order to compare different types of fMRI analysis with an existing metabolic mapping standard in the monkey and to compare directly cortical networks in human and non human primates. We will use fMRI to map visual cortical regions responsive to different types of visual stimuli and active in visual discrimination tasks in monkeys and in humans. We will within the same monkey subject compare activation maps measured with fMRI and those obtained by metabolic labeling (double label 2deoxyglucose - 2DG). This latter data will serve as ''ground truth'' with which to compare the results of the different analysis techniques for the fMRI signals. We will also use ICA to develop new tools to estimate functional connectivity and compare this to the extensive anatomical knowledge available in the monkey.

Keywords: visual cortex, magnetic resonance imaging, functional MRI, monkeys, humans, functional mapping, activity maps, metabolic labeling, registration