Greater sensitivity of the cortical face processing system to perceptually-equated face detection

Abstract

Face detection, the perceptual capacity to identify a visual stimulus as a face before probing deeper into specific attributes (such as its identity or emotion), is essential for social functioning. Despite the importance of this functional capacity, face detection and its underlying brain mechanisms are not well understood. This study evaluated the roles that the cortical face processing system, which is identified largely through studying other aspects of face perception, play in face detection. Specifically, we used functional magnetic resonance imaging (fMRI) to examine the activations of the fusifom face area (FFA), occipital face area (OFA) and superior temporal sulcus (STS) when face detection was isolated from other aspects of face perception and when face detection was perceptually-equated across individual human participants (n=20). During face detection, FFA and OFA were significantly activated, even for stimuli presented at perceptual-threshold levels, whereas STS was not. During tree detection, however, FFA and OFA were responsive only for highly salient (i.e., high contrast) stimuli. Moreover, activation of FFA during face detection predicted a significant portion of the perceptual performance levels that were determined psychophysically for each participant. This pattern of result indicates that FFA and OFA have a greater sensitivity to face detection signals and selectively support the initial process of face vs. non-face object perception.

Impairments of facial detection in tobacco use disorder: baseline data and impact of smoking duration

“… 9 The ability to detect and, subsequently, process the details of a visual scene is determined by the ability of the visual system to isolate and characterize differences in contrast, color, and shape, to cite just a few. 10 , 11 Thus, the ability to detect faces in visual scenes involves the detection of variations not only in facial characteristics, 9 but also in environmental and health conditions. In addition, it is related to the perceptive capacity of the observer.…”

Recognition memory for low- and high-frequency-filtered emotional faces: Low spatial frequencies drive emotional memory enhancement, whereas high spatial frequencies drive the emotion-induced recognition bias

“…Although the specific contrast-response functions vary across brain areas and specific cells, many neuronal responses are nearly saturated at Michelson contrasts above 0.3 (e.g., V1 and LGN;Sclar, Maunsell, & Lennie, 1990) or at less than 40% RMS contrast (in V1 and fusiform face area (FFA);Yue, Cassidy, Devaney, Holt, & Tootell, 2011). A recent study byMaher et al (2016) also showed that the FFA already responds to faces at very low contrasts, and that the response does not change with increasing contrast. Thus, it is very unlikely that differences in the RMS contrasts of the stimuli had an influence onto the results.Mem Cogn (2017) 45:699-715…”