Increased Early Sensitivity to Eyes in Mouthless Faces: In Support of the LIFTED Model of Early Face Processing
- 299 Downloads
The N170 ERP component is a central neural marker of early face perception usually thought to reflect holistic processing. However, it is also highly sensitive to eyes presented in isolation and to fixation on the eyes within a full face. The lateral inhibition face template and eye detector (LIFTED) model (Nemrodov et al. in NeuroImage 97:81–94, 2014) integrates these views by proposing a neural inhibition mechanism that perceptually glues features into a whole, in parallel to the activity of an eye detector that accounts for the eye sensitivity. The LIFTED model was derived from a large number of results obtained with intact and eyeless faces presented upright and inverted. The present study provided a control condition to the original design by replacing eyeless with mouthless faces, hereby enabling testing of specific predictions derived from the model. Using the same gaze-contingent approach, we replicated the N170 eye sensitivity regardless of face orientation. Furthermore, when eyes were fixated in upright faces, the N170 was larger for mouthless compared to intact faces, while inverted mouthless faces elicited smaller amplitude than intact inverted faces when fixation was on the mouth and nose. The results are largely in line with the LIFTED model, in particular with the idea of an inhibition mechanism involved in holistic processing of upright faces and the lack of such inhibition in processing inverted faces. Some modifications to the original model are also proposed based on these results.
KeywordsFaces Eyes N170 ERPs Gaze-contingent procedure Inhibition
This work was supported by the Natural Sciences and Engineering Research Council of Canada (NSERC Discovery Grants #418431); the Ontario government (Early Researcher Award, ER11-08-172); the Canada Foundation for Innovation (Grant #213322); and the Canada Research Chairs program (Grants #213322 and #230407) to RJI. We would also like to thank Marina Ren for help with testing, supported by an NSERC Undergraduate Studies Research Award (USRA).
- Eimer M (2011) The face-sensitive N170 component of the event-related brain potential. In: Calder AJ, Rhodes G, Johnson MH and Haxby JV (eds) The oxford handbook of face perception. Oxford University Press, Oxford, pp. 329–344Google Scholar
- Rossion B (2009) Distinguishing the cause and consequence of face inversion: the perceptual field hypothesis. Acta Physiol 132(3):300–312Google Scholar
- Rossion B, Jacques C (2012) The N170: understanding the time course of face perception in the human brain. In: Luck SJ, and Kappenman ES (eds) The oxford handbook of event-related potential components. Oxford university Press, Oxford, pp. 115–141Google Scholar
- Rossion B, Gauthier I, Tarr MJ, Despland P, Bruyer R, Linotte S et al (2000) The N170 occipito-temporal component is delayed and enhanced to inverted faces but not to inverted objects: an electrophysiological account of face-specific processes in the human brain. Neuroreport 11(120147456):69–74CrossRefPubMedGoogle Scholar
- Shepherd J, Davies G, Ellis H (1981) Studies of cue saliency. In: Davies G, Ellis HD, Shepherd J (eds) Perceiving and remembering faces. Academic Press, New York, pp 105–131Google Scholar
- Tanaka JW, Gordon I (2011) Features, configuration, and holistic face processing. In: Calder AJ, Rhodes G, Johnson MJ, Haxby JV (eds) The Oxford handbook of face perception. Oxford University Press, New York, pp 177–194Google Scholar