Functional anatomy and neural mechanisms of face recognition in macaque monkeys using fMRI, electrophysiology, and microstimulation.
Final Report Abstract
Research conducted in this project has revealed new insights into the neural mechanisms of object recognition. The project was focused on understanding and characterizing the neural substrate efface recognition in macaque monkeys, but in two projects we aimed to take the approach into other domains of visual information processing and across species boundaries to compare face processing in macaque monkeys and humans. The approach we used is characterized by the combination of functional magnetic resonance imaging, a technique that provides an overview over functional specializations within the entire brain, and electrophysiological techniques targeted to regions of functional specialization for faces ("face patches") in order to investigate the properties of individual cells within these regions. Thus two different levels of organization can be bridged: brain regions and single neurons. Our chief discoveries were: (1) the six face patches in the macaque temporal lobe are selectively coupled to each other to form an integrated face-processing network. (2) This network extends into prefrontal cortex including three more face-selective areas. (3) Of four face patches targeted for electrophysiological recordings, each was entirely devoted to face processing, but each revealed a unique functional specialization for a different aspect efface recognition. (4) A detailed, quantitative characterization efface representations in two face areas revealed that cells in this region encode individual faces, but that this representation depends on holistic face properties. (5) Multiple face-selective areas exist in humans, including one hitherto unknown area anterior to the Fusiform Face Area. Thus similarities in systems for face representations exist in two species separated by some fifteen million years of evolution.
Publications
- Comparing face patch systems in macaques and humans, Proceedings National Academy of Science 2008
Doris Y. Tsao, Sebastian Moeller, and Winrich A. Freiwald
- Patches of face-selective cortex in the macaque frontal lobe, Nature Neuroscience 2008
Doris Y. Tsao, Nicole Schweers, Sebastian Moeller, Winrich A. Freiwald
- Patches with Links: A Unified System for Processing Faces in the Macaque Temporal Lobe, Science 2008
Sebastian Moeller, Winrich A. Freiwald, Doris Y. Tsao
- Face Feature Space in the Macaque Temporal Lobe, Nature Neuroscience 2009
Winrich A. Freiwald, Doris Y. Tsao, Margaret S. Livingstone
- Functional connectivity of the macaque brain across stimulus and arousal states, Journal of Neuroscience 2009
Sebastian Moeller, Nambi Nallasamy, Doris Y. Tsao, Winrich A. Freiwald