Interference between face and non-face domains of perceptual expertise: a replication and extension

Holistic processing is modulated by the probability that parts contain task-congruent information

Holistic processing of face and non-face stimuli has been framed as a perceptual strategy, with classic hallmarks of holistic processing, such as the composite effect, reflecting a failure of selective attention, which is a consequence of this strategy. Further, evidence that holistic processing is impacted by training different patterns of attentional prioritization suggest that it may be a result of learned attention to the whole, which renders it difficult to attend to only part of a stimulus. If so, holistic processing should be modulated by the same factors that shape attentional selection, such as the probability that distracting or task-relevant information will be present. In contrast, other accounts suggest that it is the match to an internal face template that triggers specialized holistic processing mechanisms. Here we probed these accounts by manipulating the probability, across different testing sessions, that the task-irrelevant face part in the composite face task will contain task-congruent or -incongruent information. Attentional accounts of holistic processing predict that when the probability that the task-irrelevant part contains congruent information is low (25%), holistic processing should be attenuated compared to when this probability is high (75%). In contrast, template-based accounts of holistic face processing predict that it will be unaffected by manipulation given the integrity of the faces remains intact. Experiment 1 found evidence consistent with attentional accounts of holistic face processing and Experiment 2 extends these findings to holistic processing of non-face stimuli. These findings are broadly consistent with learned attention accounts of holistic processing.

The time course of holistic processing is similar for face and non-face Gestalt stimuli

There is evidence that holistic processing of faces and other stimuli rich in Gestalt perceptual grouping cues recruit overlapping mechanisms at early processing stages, but not at later stages where faces and objects of expertise likely overlap. This has led to suggestions of dual pathways supporting holistic processing; an early stimulus-based pathway (supporting processing of stimuli rich in perceptual grouping cues) and an experience-based pathway (supporting processing of object of expertise), with both pathways supporting face processing. Holistic processing markers are present when upright faces are presented for as little as 50-ms. If the overlap between holistic processing of faces and stimuli rich in grouping cues occurs early in processing, markers of holistic processing for these Gestalt stimuli should be present as early as those for faces. In Experiment 1, we investigate the time-course of the emergence of holistic processing markers for face and non-face Gestalt stimuli. The emergence of these markers for faces and the Gestalt stimuli was strikingly similar; both emerged with masked presentations as little as 50-ms. In Experiment 2, where the stimulus presentation was not masked, thus the presentation duration, but not the post-presentation perceptual processing, was constrained, patterns of holistic processing for these stimuli still did not diverge. These findings are consistent with an early, and possibly extended, temporal locus for the overlap in the holistic processing of faces and non-face stimuli rich in grouping cues.

The constancy of the holistic processing of unfamiliar faces: Evidence from the study-test consistency effect and the within-person motion and viewpoint invariance

It has been well documented that static face processing is holistic. Faces contain variant (e.g., motion, viewpoint) and invariant (race, sex) features. However, little research has focused on whether holistic face representations are tolerant of within-person variations. The present study thus investigated whether holistic face representations of faces are tolerant of within-person motion and viewpoint variations by manipulating study-test consistency using a complete composite paradigm. Participants were shown two faces sequentially and were asked to judge whether the faces' top halves were identical or different. The first face was a static face or a dynamic face rotated in depth at 30°, 60°, and 90°. The second face was either a different front-view static face (Experiment 1a, study-test inconsistent) or identical to the first face (Experiment 1b, study-test consistent). In Experiment 2, study-test consistency was manipulated within subjects, and inverted faces were included. Our results show that study-test consistency significantly enhanced the holistic processing of upright and inverted faces; this study-test consistency effect and holistic processing were not modulated by motion and viewpoint changes via depth rotation. Interestingly, we found holistic processing for moving study-test consistent inverted faces, but not for static inverted faces. What these results tell us about the nature of holistic face representation is discussed in depth with respect to earlier and current theories on face processing.

Car expertise does not compete with face expertise during ensemble coding

When objects from two categories of expertise (e.g., faces and cars in dual car/face experts) are processed simultaneously, competition occurs across a variety of tasks. Here, we investigate whether competition between face and car processing also occurs during ensemble coding. The relationship between single object recognition and ensemble coding is debated, but if ensemble coding relies on the same ability as object recognition, we expect cars to interfere with ensemble coding of faces as a function of car expertise. We measured the ability to judge the variability in identity of arrays of faces, in the presence of task-irrelevant distractors (cars or novel objects). On each trial, participants viewed two sequential arrays containing four faces and four distractors, judging which array was the more diverse in terms of face identity. We measured participants' car expertise, object recognition ability, and face recognition ability. Using Bayesian statistics, we found evidence against competition as a function of car expertise during ensemble coding of faces. Face recognition ability predicted ensemble judgments for faces, regardless of the category of task-irrelevant distractors. The result suggests that ensemble coding is not susceptible to competition between different domains of similar expertise, unlike single-object recognition.

Alternating dual-task interference between visual words and faces

The many-to-many hypothesis proposes that face and visual word recognition share and even compete for high-level perceptual resources in both hemispheres. However, it is still not clear whether the processing performed by the two hemispheres on faces and visual words is equivalent or complementary. We performed an alternating dual-task experiment to determine if the processing of visual words and faces interfered with each other, and if such interference depended upon the stimulus attribute being processed. Subjects saw a series of alternating stimuli and made same-different judgments comparing the current stimulus with the one two trials before. In some blocks faces or visual words alternated with colored gratings, in other blocks they alternated between different sets of words or different sets of faces. In the key experimental blocks they alternated between visual words and faces. Subjects were also asked to focus on different properties of the stimuli (identity or speech sounds for faces, handwriting or word content for visual words, color or orientation for gratings). There was no evidence of specific interference when subjects alternated between face and word attributes thought to be processed by opposite hemispheres (e.g. face identity and word identity, facial speech and handwriting). Rather interference occurred when subjects alternated between attributes that may be processed by the same hemisphere. The results support a modified version of the many-to-many hypothesis which takes into account complementary functions of the left and the right hemispheres in the processing of faces and visual words.

Real world familiarity does not reduce susceptibility to emotional disruption of perception: evidence from two temporal attention tasks

The visual system has been found to prioritise emotional stimuli so robustly that their presence can temporarily "blind" people to non-emotional targets in their direct line of vision. This has ostensible implications for the real world: medics must not be blinded to important information despite the trauma they confront, and drivers must not be blinded when passing emotionally engaging billboards. One possibility is that the familiarity of goal-relevant information can protect people's perception of it despite emotional distraction (e.g. drivers' perception might be less impaired by graphic ads when on a familiar road). In two experiments, we tested whether familiarity renders targets more perceptible following the presentation of an emotional distractor in two temporal attention tasks, emotion-induced blindness (Experiment 1) and the attentional blink (Experiment 2). Targets were pictures of familiar or unfamiliar locations. Although, overall, familiar targets were seen better than unfamiliar targets in both studies, stimulus familiarity did not reduce the relative perceptual impairments caused by emotional distractors.

Neuroemergentism: A Framework for Studying Cognition and the Brain

There has been virtual explosion of studies published in cognitive neuroscience primarily due to increased accessibility to neuroimaging methods, which has led to different approaches in interpretation. This review seeks to synthesize both developmental approaches and more recent views that consider neuroimaging. The ways in which Neuronal Recycling, Neural Reuse, and Language as Shaped by the Brain perspectives seek to clarify the brain bases of cognition will be addressed. Neuroconstructivism as an additional explanatory framework which seeks to bind brain and cognition to development will also be presented. Despite sharing similar goals, the four approaches to understanding how the brain is related to cognition have generally been considered separately. However, we propose that all four perspectives argue for a form of Emergentism in which combinations of smaller elements can lead to a greater whole. This discussion seeks to provide a synthesis of these approaches that leads to the emergence of a theory itself. We term this new synthesis Neurocomputational Emergentism (or Neuromergentism for short).