High-level face shape adaptation depends on visual awareness: Evidence from continuous flash suppression

AbstractOur capacity to become aware of visual stimuli is limited. Investigating these limits, Cohen et al. (2015, Journal of Cognitive Neuroscience) found that certain object categories (e.g., faces) were more effective in blocking awareness of other categories (e.g., buildings) than other combinations (e.g., cars/chairs) in the continuous flash suppression (CFS) task. They also found that more category-pair representational similarity in higher visual cortex was related to longer category-pair breakthrough times suggesting a high-level representational architecture bottleneck for visual awareness. As the cortical representations of hands and tools overlap, these categories are ideal to test this further. We conducted CFS experiments and predicted longer breakthrough times for hands/tools compared to other pairs. In contrast to these predictions, participants were generally faster at detecting targets masked by hands or tools compared to other mask categories when giving manual (Experiment 1) or vocal responses (Experiment 2). Furthermore, we found the same inefficient mask effect for hands in the context of the categories used by Cohen et al. (2015) and found a similar behavioural pattern as the original paper (Experiment 3). Exploring potential low-level explanations, we found that the category average for edges (e.g. hands have less detail compared to cars) was the best predictor for the data. However, these category-specific image characteristics could not completely account for the Cohen et al. (2015) category pattern or for the hand/tool effects. Thus, several low- and high-level object category-specific limits for visual awareness are plausible and more investigations are needed to further tease these apart.

Download Full-text

No impact of affective person knowledge on visual awareness: Evidence from binocular rivalry and continuous flash suppression.

Emotion ◽

10.1037/emo0000305 ◽

2017 ◽

Vol 17 (8) ◽

pp. 1199-1207 ◽

Cited By ~ 6

Author(s):

Timo Stein ◽

Caitlyn Grubb ◽

Maria Bertrand ◽

Seh Min Suh ◽

Sara C. Verosky

Keyword(s):

Binocular Rivalry ◽

Visual Awareness ◽

Continuous Flash Suppression

Download Full-text

Neural Correlates of Motion-induced Blindness in the Human Brain

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2009.21262 ◽

2010 ◽

Vol 22 (6) ◽

pp. 1235-1243 ◽

Cited By ~ 14

Author(s):

Marieke L. Schölvinck ◽

Geraint Rees

Keyword(s):

Visual Cortex ◽

Visual Processing ◽

Target Location ◽

Visual Awareness ◽

Neural Correlates ◽

Low Level ◽

Bistable Perception ◽

Visual Phenomenon ◽

High Level ◽

Visual Cortical

Motion-induced blindness (MIB) is a visual phenomenon in which highly salient visual targets spontaneously disappear from visual awareness (and subsequently reappear) when superimposed on a moving background of distracters. Such fluctuations in awareness of the targets, although they remain physically present, provide an ideal paradigm to study the neural correlates of visual awareness. Existing behavioral data on MIB are consistent both with a role for structures early in visual processing and with involvement of high-level visual processes. To further investigate this issue, we used high field functional MRI to investigate signals in human low-level visual cortex and motion-sensitive area V5/MT while participants reported disappearance and reappearance of an MIB target. Surprisingly, perceptual invisibility of the target was coupled to an increase in activity in low-level visual cortex plus area V5/MT compared with when the target was visible. This increase was largest in retinotopic regions representing the target location. One possibility is that our findings result from an active process of completion of the field of distracters that acts locally in the visual cortex, coupled to a more global process that facilitates invisibility in general visual cortex. Our findings show that the earliest anatomical stages of human visual cortical processing are implicated in MIB, as with other forms of bistable perception.

Download Full-text

Disentangling Perceptual Awareness from Non-conscious Processing in Rhesus Monkeys (Macaca mulatta)

10.31234/osf.io/h7dxg ◽

2021 ◽

Author(s):

Moshe Shay Ben-Haim ◽

Olga Dal Monte ◽

Nicholas A. Fagan ◽

Yarrow Dunham ◽

Ran Hassin ◽

...

Keyword(s):

Macaca Mulatta ◽

Rhesus Monkeys ◽

Visual Awareness ◽

Empirical Approach ◽

Perceptual Awareness ◽

Human Species ◽

Double Dissociation ◽

Modes Of Processing ◽

Conscious Processing ◽

High Level

Scholars have long debated whether animals, which display impressive intelligent behaviors, are consciously aware or not. Yet, because many complex human behaviors and high-level functions can be performed without conscious awareness, it was long considered impossible to untangle whether animals are aware, or just conditionally or non-consciously behaving. Here, we developed a novel empirical approach to address this question. We harnessed a well-established crossover double dissociation between non-conscious and conscious processing, in which people perform in completely opposite ways when they are aware of stimuli versus when they are not. To date, no one has explored if similar performance dissociations exist in a non-human species. In a series of seven experiments, we first established these signatures in humans using both known and newly developed non-verbal double dissociation tasks, and then identified similar signatures in rhesus monkeys (Macaca mulatta). These results provide robust evidence for two distinct modes of processing in non-human primates. This empirical approach makes it feasible to disentangle conscious visual awareness from non-conscious processing in non-human species; hence, it can be used to strip away ambiguity when exploring the processes governing intelligent behavior across the animal kingdom. Taken together, these results strongly support the existence of both non-conscious processing as well as functional human-like visual awareness in non-human animals.

Download Full-text

Continuous Flash Suppression Known and Unknowns

10.31234/osf.io/sk8mb ◽

2019 ◽

Author(s):

Ali Pournaghdali ◽

Bennett L Schwartz

Keyword(s):

Visual Processing ◽

Visual Information ◽

Continuous Flash Suppression ◽

Low Level ◽

Experimental Configuration ◽

High Level ◽

The Impact ◽

Nonconscious Perception

Studies utilizing continuous flash suppression (CFS) provide valuable information regarding conscious and nonconscious perception. There are, however, crucial unanswered questions regarding the mechanisms of suppression and the level of visual processing in the absence of consciousness with CFS. Research suggests that the answers to these questions depend on the experimental configuration and how we assess consciousness in these studies. The aim of this review is to evaluate the impact of different experimental configurations and the assessment of consciousness on the results of the previous CFS studies. We review studies that evaluated the influence of different experimental configuration on the depth of suppression with CFS and discuss how different assessments of consciousness may impact the results of CFS studies. Finally, we review behavioral and brain recording studies of CFS. In conclusion, previous studies provide evidence for survival of low-level visual information and complete impairment of high-level visual information under the influence of CFS. That is, studies suggest that nonconscious perception of lower-level visual information happens with CFS but there is no evidence for nonconscious highlevel recognition with CFS.

Download Full-text

Overly strong priors for socially meaningful visual signals in psychosis proneness

10.1101/473421 ◽

2018 ◽

Cited By ~ 1

Author(s):

Heiner Stuke ◽

Elisabeth Kress ◽

Veith Andreas Weilnhammer ◽

Philipp Sterzer ◽

Katharina Schmack

Keyword(s):

Predictive Coding ◽

Sensory Information ◽

Auditory Hallucinations ◽

Visual Signals ◽

Visual Modality ◽

Continuous Flash Suppression ◽

Direct Gaze ◽

Psychosis Proneness ◽

High Level ◽

Meaningful Stimuli

ABSTRACTPredictive coding accounts of psychosis state that an overweighing of high-level priors relative to sensory information may lead to the misperception of meaningful signals underlying the experience of auditory hallucinations and delusions. However, it is currently unclear whether the hypothesized overweighing of priors (1) represents a pervasive alteration that also affects the visual modality, and, (2) takes already effect at early automatic processing stages.Here, we addressed these questions by studying visual perception of socially meaningful stimuli in healthy individuals with varying degrees of psychosis proneness (n=39). In a first task, we quantified participants’ prior for detecting faces in visual noise. In a second task, we measured participants’ prior for detecting direct gaze stimuli that were rendered invisible by continuous flash suppression. We found that the prior for detecting faces in noise correlated with hallucination proneness (rho=0.50, p=0.001) as well as delusion proneness (rho=0.44, p=0.005). Similarly, the prior for detecting invisible direct gaze was significantly associated with hallucination proneness (rho = 0.42, p = 0.010) and trend-wise with delusion proneness (rho = 0.29, p = 0.087). Our results provide evidence for the idea that overly strong high-level priors for automatically detecting socially meaningful stimuli might constitute a generic processing alteration in psychosis.

Download Full-text

Real-world regularities facilitate visual awareness of objects under continuous flash suppression

Journal of Vision ◽

10.1167/15.12.1039 ◽

2015 ◽

Vol 15 (12) ◽

pp. 1039

Author(s):

Timo Stein ◽

Daniel Kaiser ◽

Marius Peelen

Keyword(s):

Real World ◽

Visual Awareness ◽

Continuous Flash Suppression

Download Full-text

Faces in commonly experienced configurations enter awareness faster due to their curvature relative to fixation

PeerJ ◽

10.7717/peerj.1565 ◽

2016 ◽

Vol 4 ◽

pp. e1565 ◽

Cited By ~ 9

Author(s):

Pieter Moors ◽

Johan Wagemans ◽

Lee de-Wit

Keyword(s):

Fusiform Face Area ◽

General Shape ◽

Continuous Flash Suppression ◽

Face Area ◽

Contrast Adaptation ◽

Neuroimaging Study ◽

Face Stimuli ◽

High Level ◽

Visual Properties ◽

Processing Mechanisms

The extent to which perceptually suppressed face stimuli are still processed has been extensively studied using the continuous flash suppression paradigm (CFS). Studies that rely on breaking CFS (b-CFS), in which the time it takes for an initially suppressed stimulus to become detectable is measured, have provided evidence for relatively complex processing of invisible face stimuli. In contrast, adaptation and neuroimaging studies have shown that perceptually suppressed faces are only processed for a limited set of features, such as its general shape. In this study, we asked whether perceptually suppressed face stimuli presented in their commonly experienced configuration would break suppression faster than when presented in an uncommonly experienced configuration. This study was motivated by a recent neuroimaging study showing that commonly experienced face configurations are more strongly represented in the fusiform face area. Our findings revealed that faces presented in commonly experienced configurations indeed broke suppression faster, yet this effect did not interact with face inversion suggesting that, in a b-CFS context, perceptually suppressed faces are potentially not processed by specialized (high-level) face processing mechanisms. Rather, our pattern of results is consistent with an interpretation based on the processing of more basic visual properties such as convexity.

Download Full-text

Not All Emotions Are Equal: Fear Chemosignals Lower Awareness Thresholds Only for Fearful Faces

Chemical Senses ◽

10.1093/chemse/bjaa047 ◽

2020 ◽

Vol 45 (7) ◽

pp. 601-608

Author(s):

Fábio Silva ◽

Nuno Gomes ◽

Sebastian Korb ◽

Gün R Semin

Keyword(s):

Facial Expressions ◽

Visual Processing ◽

Visual Awareness ◽

Emotional States ◽

Body Odor ◽

Emotional Facial Expressions ◽

Continuous Flash Suppression ◽

Fearful Faces ◽

Processing Stream ◽

Body Odors

Abstract Exposure to body odors (chemosignals) collected under different emotional states (i.e., emotional chemosignals) can modulate our visual system, biasing visual perception. Recent research has suggested that exposure to fear body odors, results in a generalized faster access to visual awareness of different emotional facial expressions (i.e., fear, happy, and neutral). In the present study, we aimed at replicating and extending these findings by exploring if these effects are limited to fear odor, by introducing a second negative body odor—that is, disgust. We compared the time that 3 different emotional facial expressions (i.e., fear, disgust, and neutral) took to reach visual awareness, during a breaking continuous flash suppression paradigm, across 3 body odor conditions (i.e., fear, disgust, and neutral). We found that fear body odors do not trigger an overall faster access to visual awareness, but instead sped-up access to awareness specifically for facial expressions of fear. Disgust odor, on the other hand, had no effects on awareness thresholds of facial expressions. These findings contrast with prior results, suggesting that the potential of fear body odors to induce visual processing adjustments is specific to fear cues. Furthermore, our results support a unique ability of fear body odors in inducing such visual processing changes, compared with other negative emotional chemosignals (i.e., disgust). These conclusions raise interesting questions as to how fear odor might interact with the visual processing stream, whilst simultaneously giving rise to future avenues of research.

Download Full-text

The advantage of fear stimuli in accessing visual awareness

European Psychiatry ◽

10.1016/j.eurpsy.2016.01.1337 ◽

2016 ◽

Vol 33 (S1) ◽

pp. S373-S373

Author(s):

N. Gomes ◽

S. Silva ◽

C. Silva ◽

J. Azevedo ◽

S. Soares

Keyword(s):

Emotional Disorders ◽

Response Times ◽

Visual Awareness ◽

Neural System ◽

Human Cognition ◽

Privileged Access ◽

Continuous Flash Suppression ◽

Suppression Technique ◽

Conscious Processing ◽

Competing Interest

IntroductionSeveral studies have shown that evolutionary relevant fear stimuli hold a privileged access to the fear module, an independent behavioral, psychophysiological and neural system that is automatically and selectively activated, and is relatively encapsulated from more advanced human cognition. However, to the best of our knowledge no study has yet directly assessed whether such stimuli are granted a facilitated access to visual awareness, compared to stimuli without such evolutionary relevance.ObjectiveIn the present study we used an interocular suppression technique, the Continuous Flash Suppression, known to reduce the activity along the geniculostriate pathway and to strongly suppress processing in the visual cortex.AimOur goal was to investigate whether ecologically relevant fear stimuli (snakes and spiders) overcame suppression and accessed awareness to a larger extent than non-evolutionary relevant animal stimuli (birds).MethodThirty university students volunteered to participate. Participants were asked to identify the screen quadrant in which the stimulus was presented in order to ensure that there was indeed a conscious processing.ResultsThe results confirmed our hypothesis by showing an advantage of fear stimuli (snakes and spiders) over the control stimulus (birds) in emerging from suppression into awareness, which was evidenced by significantly shorter response times.ConclusionsOur findings support the notion that evolutionary relevant stimuli hold a privileged access into awareness, most likely involving a direct brainstem-thalamic route to the amygdala. Importantly, they contribute to elucidate the functions and mechanisms of the fear system and may have important implications for understanding emotional disorders, since many of these involve the fear system.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Download Full-text