Abstract
Configural face processing is considered to be vital for face perception. If configural face processing requires an evaluation of spatial information, might this process involve interactions between ventral stream face-processing regions and dorsal stream visuospatial-processing regions? We explored this possibility using thetaburst stimulation (TBS) with fMRI in humans. Participants were shown two faces that differed in either the shape (featural differences) or the spatial configuration (configural differences) of their features. TBS applied on dorsal location-processing regions: 1) reduced fMRI activity within ventral stream face-processing regions during configural but not featural face processing; and 2) reduced functional connectivity between these face regions significantly more for configural than featural face processing. No changes occurred when TBS was delivered on the vertex control site for either face task. We conclude that ventral stream face-processing regions receive visuospatial information from dorsal stream location-processing regions during configural face processing.
Significance statement Face perception is thought to be mediated exclusively by neural substrates within the ventral visual pathway. However, by using non-invasive brain stimulation (thetabust transcranial magnetic stimulation) in healthy human adults, we demonstrate that the face-processing regions of the ventral visual pathway receive information from visuospatial-processing regions of the dorsal visual pathway during configural face processing, a vital function in face perception. Our findings thus indicate that veridical face perception may depend on both the ventral and dorsal visual pathways.
Footnotes
1 Contributed to the design of the experiment, the collection and analyses of the data, and writing the manuscript.
2 Contributed to the analyses of the data and writing the manuscript.
3 Contributed to the design of the experiment and writing the manuscript.
Conflict of Interest: The authors declare no competing financial interests.