Assessing the influence of emotional expressions on perceptual sensitivity to faces overcoming interocular suppression.

Abstract

Detecting faces and identifying their emotional expressions are essential for social interaction. The importance of expressions has prompted suggestions that some emotionally relevant facial features may be processed unconsciously, and it has been further suggested that this unconscious processing yields preferential access to awareness. Evidence for such preferential access has predominantly come from reaction times in the breaking continuous flash suppression (bCFS) paradigm, which measures how long it takes different stimuli to overcome interocular suppression. For instance, it has been claimed that fearful expressions break through suppression faster than neutral expressions. However, in the bCFS procedure, observers can decide how much information they receive before committing to a report, so although their responses may reflect differential detection sensitivity, they may also be influenced by differences in decision criteria, stimulus identification, and response production processes. Here, we employ a procedure that directly measures sensitivity for both face detection and identification of facial expressions, using predefined exposure durations. We apply diverse psychophysical approaches-forced-choice localization, presence/absence detection, and staircase-based threshold measurement; across six experiments, we find that emotional expressions do not alter detection sensitivity to faces as they break through CFS. Our findings constrain the possible mechanisms underlying previous findings: faster reporting of emotional expressions' breakthrough into awareness is unlikely to be due to the presence of emotion affecting perceptual sensitivity; the source of such effects is likely to reside in one of the many other processes that influence response times.

Spatial perspective and identity in visual awareness of the bodily self-other distinction

“…Additionally, disparities in the low-level visual features and/or response bias can alter breakthrough times, thereby compromising the validity of the technique for studying unconscious processes. Capitalizing on such evidence, the scientific community also relied on non-speeded accuracy-based methods with objective awareness measures 30 , 33 , 34 . However, this does not imply that the bCFS should be discarded or does not convey theoretical values.…”

“…Some of these high-level effects have been replicated also with more objective and accuracy-based techniques (e.g., face orientation 34 and eye gaze direction 48 ). However, others were not, being confounded by differences in low-level features 49 , 50 , decision criteria 33 , and object-scene integration 51 , 52 , highlighting how such factors might impact on conscious access measures misinterpreting the scopes and the limits of unconscious perception. But what about the interpretation of the specific access to awareness advantage of the first-, with respect to the third-, person perspective that we reported here?…”

Physiological arousal underlies preferential access to visual awareness of fear-conditioned (and possibly disgust-conditioned) stimuli.

“…Taking recent methodological considerations into account (Lanfranco et al, 2023a(Lanfranco et al, , 2023bStein, 2019), we decided to use an accuracy-based b-CFS method which was slightly modified to fit the purposes of the current study (Figure 1). In each of the trials, participants were presented with a target stimulus (a clipped annulus) in one eye, and a rapidly flashing mask in the other eye.…”

Intra-group differences in skin tone influence evaluative and perceptual face processing

“…The decision to employ non-Melanesian faces was motivated by two factors: First, it is well-established that faces representing one's racial group are processed more effectively and evaluated more favorably than faces from other racial groups due to being encountered more frequently during development [10][11][12]. Second, there are currently no validated databases of Melanesian faces that have been controlled for attractiveness, emotionality, and/or other features known to influence face processing [13]. Both concerns were addressed by using non-Melanesian faces from a validated database [14] categorized along ethnicity (Asian, Black, Latin, White), sex (male, female), and attractiveness (low, high).…”