Supplementary MaterialsSupplementary File. three small regions selective for Rabbit Polyclonal to HARS face were revealed in the frontal cortex by functional imaging: area PL, below the principal sulcus; PA in the anterior lender of the arcuate sulcus; and PO, in the lateral orbital sulcus (20). In these areas the hemodynamic response was stronger for face expression compared with neutral faces. This difference was stronger in the orbitofrontal cortex, suggesting that this region is involved in processing the emotional content of faces. The presence of this face-selective area among the heterogeneous functions of the surrounding orbitofrontal cortex may set the stage for multidimensional information processing related to face, person, and emotion. Specifically, surrounding areas are linked to computing reward values or preference (21C26) and to processing social information. With respect to the latter, orbitofrontal cortex (OFC) cells are modulated by the viewing of a live monkey receiving a shared prize, suggesting that cells code the value of the prize as modulated by the identity of the monkey with whom prize was shared (27). In addition, neurons in the OFC are more sensitive to rewards when they are not shared, suggesting that they code the interpersonal context of a given reward (28). Further, other neurons therein encode the motivational values of interpersonal stimuli such as dominant faces or perinea (29). In addition, there are findings from human imaging and lesion studies showing that this OFC is involved in interpersonal judgments (30, 31). In sum, we induce from this literature that neurons specifically coding faces in the orbitofrontal cortex represent interpersonal attributes of the faces. To test this hypothesis, we operationally defined social attributes as elements providing information about (= 14 for which a characterization was possible out of 32 face-selective cells) permits only tentative conclusions. Here we systematically characterized the properties of a large number of face-selective cells (= 179) recorded in the lateral orbitofrontal sulcus by addressing three questions: Are these face cells coding social dimensions of faces, such as age, gender, or expressions? Are the responses MLN4924 kinase inhibitor of these face-selective cells also triggered by a vocal stimulus, such as a call which can be considered the acoustic counterpart of the face? Are these responses modified by a learned positive or negative Pavlovian association? We also compared the results obtained with the selective face cell population to a control population of nonCface-selective cells to rule out responses based on low-level stimulus properties. Our findings reveal that only OFC face-selective cells encode faces in different categories such as facial expression, age, and gender. The cells appear to be primarily visual and are not sensitive to learned MLN4924 kinase inhibitor associations between a face and a reward or a punisher. In combination, MLN4924 kinase inhibitor these data imply that the cells provide an independent matrix within the OFC to represent socially and emotionally relevant categories. Results Identifying a Face-Selective Area. To localize the stereotaxic coordinates of the lateral orbital sulcus along which lies a robust face-selective area [PO (19, 20)], we used MRI scans on each monkey. Then we placed a recording chamber above those coordinates (for monkey Y, AP is +27, ML is +12, right hemisphere; for monkey D, AP is +31, ML is ?10, left hemisphere; and Fig. 1 0.05, one-way ANOVAs with stimulus category as a factor). This second criterion was used offline to discriminate.