Impaired holistic and analytic face processing in congenital prosopagnosia: Evidence from the eye-contingent mask/window paradigm

Abstract

There is abundant evidence that face recognition, in comparison to the recognition of other objects, is based on holistic processing rather than analytic processing. One line of research that provides evidence for this hypothesis is based on the study of people who experience pronounced difficulties in visually identifying conspecifics on the basis of their face. Earlier, we developed a behavioural paradigm to directly test analytic vs. holistic face processing. In comparison to a to be remembered reference face stimulus, one of two test stimuli was either presented in full view, with an eye-contingently moving window (only showing the fixated face feature, and therefore only affording analytic processing), or with an eye-contingently moving mask or scotoma (masking the fixated face feature, but still allowing holistic processing). In the present study we use this paradigm (that we used earlier in acquired prosopagnosia) to study face perception in congenital prosopagnosia (people having difficulties recognizing faces from birth on, without demonstrable brain damage). We observe both holistic and analytic face processing deficits in people with congenital prosopagnosia. Implications for a better understanding, both of congenital prosopagnosia and of normal face perception, are discussed.

Keywords:

• Prosopagnosia
• Face processing
• Holistic perception

The writing of the article was supported by a grant from the Fund for Scientific Research [Flanders G.0810.13], awarded to KV. GVB is supported by the Belgian National Fund for Scientific Research (FNRS).

The writing of the article was supported by a grant from the Fund for Scientific Research [Flanders G.0810.13], awarded to KV. GVB is supported by the Belgian National Fund for Scientific Research (FNRS).

Notes

¹ Köhler described the effect as follows: “For this experiment I select a picture, or outline-drawing of an object, which shows a conspicuous change in appearance when it is upside down. This is the case, for instance, with photographs of known or unknown persons. They change so much that what we call facial expression disappears almost entirely in the abnormal orientation” (1940, p. 25–26).

² Note that, because the window and mask conditions also differ in terms of their reliance on foveal and peripheral processing (in addition to the analytic vs. holistic difference), this tendency could imply that patients might be differentially impacted by the absence of fine perceptual detail in the mask condition (Reingold, 2002). We are examining this issue by systematically manipulating the spatial frequency content of the face stimuli.