Human Face Identity Categorization: Bridging the Gap between Vision and Social Semantics

Introduction

HUMANFACE is based on a proposed global theory of human face identity recognition, conceptualized as a categorization function (i.e., Face Identity Categorization, FIC). FIC is considered the pinnacle of categorization in human adults, who perform this function rapidly and automatically, despite a large, undetermined, and flexible number of categories of identities experienced throughout life.

Theoretical Hypothesis

The core theoretical hypothesis of HUMANFACE is that semantic representations of person identity precede and guide the development of visual face identity representations throughout a lifetime. Hence, contrary to standard theoretical models, there is no border between visual perception and semantic memory, but a postero-anterior gradient of sensitivity to physical and semantic features of identity in the human ventral occipito-temporal cortex (vOTC).

Integration of Observations

The theory integrates a number of observations from single neurons to behavior, making predictions tested in five work packages:

1. WP1: Valid measures of rapid, automatic FIC in human adults are optimized, to be used in WP2, testing the modulation of FIC by, and integration with, social semantics.

2. WP3: To map the neural basis of FIC as constrained by social semantics, including its temporal dynamics and critical relation to behavior, WP3 consists of intracerebral recordings and stimulation across the vOTC.

3. WP4: To show the emergence and strengthening of representations of facial identity by multimodal person knowledge, studies in infants and children will be conducted in WP4.

4. WP5: Finally, to test hypotheses about the coding of facial identities across degenerate minicolumns of neurons, recordings will be made at the level of single neurons in the vOTC.

Expected Outcomes

The project will generate a large corpus of data and original methodologies to make decisive progress in understanding one of the most complex functions of the human mind/brain, shedding new light on how humans give meaning to their physical and social environment.