Marlene Behrmann¹ (), Galia Avidan², Janita N. Turchi³, Fadila Hadj-Bouziane⁴, Ning Liu⁵; ¹Department of Ophthalmology, University of Pittsburgh, and Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213 USA, ²Department of Psychology, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel, ³Laboratory of Neuropsychology, NIMH, NIH, Bethesda, Maryland, 20892, USA, ⁴INSERM, U1028, CNRS UMR5292, Lyon Neuroscience Research Center, ImpAct Team, Lyon, F-69000, France, ⁵State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China

Although the presence of face patches in primate inferotemporal (IT) cortex is well established, the functional and causal relationships among these patches remain elusive. In two monkeys, muscimol was infused sequentially into each patch or pair of patches to assess their respective influence on the remaining IT face network and on the amygdala, as determined using fMRI. The results revealed that anterior face patches required input from middle face patches for their responses to both faces and objects, while the face selectivity in middle face patches arose, in part, from top-down input from anterior face patches. Moreover, we uncovered a parallel fundal-lateral functional organization in the IT face network, supporting dual routes (dorsal-ventral) in face processing within IT cortex as well as between IT cortex and the amygdala. These findings of the causal relationship among the face patches demonstrate that the IT face circuit is organized into multiple functional compartments.

Acknowledgements: This work was supported by the NIMH Intramural Research Program to LGU, and a grant from the NEI, support from P30 CORE award, NEI, and funds from The Research to Prevent Blindness Inc, NY, and the Eye & Ear Foundation of Pittsburgh to MB.