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Modularity of Mind and Brain and the Case of the FFA| title | Modularity of Mind and Brain and the Case of the FFA |
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| start_date | 2023/12/07 |
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| schedule | 14h |
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| online | no |
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| location_info | Salle des Actes |
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| summary | Is the human mind structured, and if so what is that structure ? This classic question, long the purview of philosophers, became scientifically tractable first as neurologists studied the sometimes specific cognitive deficits that resulted from brain damage, later as cognitive and developmental psychologists traced dissociations in the cognitive abilities of infants and children, and most recently as cognitive neuroscientists measured neural responses from the human brain. In this lecture I consider the case of face perception, charting the many lines of evidence that specialized neural machinery in the fusiform gyrus plays a specific and causal role in the perception and recognition of faces. The advent of fMRI in the 1990s for the first time enabled us to find and characterize the fusiform face area (FFA) noninvasively in normal subjects, and hence to study it in detail. Because the precise location of this region varies across individuals, we first localize it functionally in each participant individually, and then measure its response in a wide variety of conditions. We found that the FFA is a parade case of functional specificity, responding twice as strongly to faces as to any other stimuli. The response of this region is correlated with awareness of a face in binocular rivalry, modulated by spatial and object-based attention, and selectively increased when people closed their eyes and simply imagine faces. Electrical stimulation of the FFA produces a face percept, demonstrating the selective causal role of this region in face perception. Tsao and Freiwald further showed that macaques have similar face-selective patches, and then used the powerful tools available in animals to map out the sequence of representations across these face patches and their connectivity. The upshot of this story is that at least one patch of the human brain is extremely specific for the single mental function of face perception. But that conclusion raises an obvious question, tackled in the next lecture. |
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| responsibles | de Vignemont |
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Workflow history| from state (1) | to state | comment | date |
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| submitted | published | | 2023/09/26 13:56 UTC |
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