The functional neuroanatomy of face perception

Summary

Date: 
December 8, 2015 - 12:00pm
Location: 
NW 243
About the Speaker
Name: 
Kalanit Grill-Spector (Stanford)

I will describe recent results from my lab examining the computations, representations, and neural implementation of the cortical system for face perception. Specifically, I will present data arguing against prevailing ideas that receptive fields and anatomy are irrelevant for understanding the function of high-level visual areas, such as those involved in face perception.

In contrast to predictions of classical theories, recent data from our lab reveals that computations in face-selective regions in human ventral temporal cortex can be characterized with a population receptive field (pRF) model, which predicts the location and spatial extent of the visual field that is processed by the neural population in a voxel. Additionally, our research shows that attention to faces modulates pRF properties in face-selective regions, consequently enhancing the representation of faces in the peripheral visual field where visual acuity is the lowest. Furthermore, our data demonstrate that pRF properties in VTC are correlated with face perception abilities: participants with larger pRFs perform better in face recognition. These data suggest that computations performed by pRFs in face-selective regions may form a neural basis for holistic processing necessary for face recognition.

Finally, I will describe recent observations showing that spatial organization of functional regions in ventral temporal cortex relative to the anatomy is much more consistent than previously thought. These observations have led us to examine which factors may constrain this organization. We find that both the long-range white matter connections and the underlying cytoarchitectonic organization constrain the location of functional regions in ventral temporal cortex. Overall, these data highlight the importance of elucidating fundamental computational and anatomical properties of neural populations, as they offer a new mechanistic understanding of the neural basis of face perception.

This work has been done in collaboration with Kevin Weiner, Kendrick Kay, Nathan Witthoft & Jesse Gomez.