Breaking Continuous Flash Suppression Research Articles

Statistical Learning Facilitates Access to Awareness

Statistical learning is a powerful mechanism that enables the rapid extraction of regularities from sensory inputs. Although numerous studies have established that statistical learning serves a wide range of cognitive functions, it remains unknown whether statistical learning impacts conscious access. To address this question, we applied multiple paradigms in a series of experiments (N = 153 adults): Two reaction-time-based breaking continuous flash suppression (b-CFS) experiments showed that probable objects break through suppression faster than improbable objects. A preregistered accuracy-based b-CFS experiment showed higher localization accuracy for suppressed probable (versus improbable) objects under identical presentation durations, thereby excluding the possibility of processing differences emerging after conscious access (e.g., criterion shifts). Consistent with these findings, a supplemental visual-masking experiment reaffirmed higher localization sensitivity to probable objects over improbable objects. Together, these findings demonstrate that statistical learning alters the competition for scarce conscious resources, thereby potentially contributing to established effects of statistical learning on higher-level cognitive processes that require consciousness.

Unconscious prioritization for face-to-face people.

One central question in the scientific and philosophical study of consciousness is regarding the scope of human consciousness. There is a lively debate as to whether high-level information integration is necessarily dependent on consciousness. This study presents a new form of unconscious integration based on the facingness between two individuals. Using a breaking continuous flash suppression paradigm, Experiments 1-3 found that two facing human heads got a privilege in breaking into awareness compared to nonfacing pairs. Experiments 4 and 5 demonstrated that the breakthrough difference between facing and nonfacing pairs could not be attributed to low-level or mid-level factors. Experiments 6, 7a, and 7b showed that the unconscious priority of facing pairs was significantly diminished when the holistic processing of the two agents was disrupted. Experiments 8-11 demonstrated that the advantage of facing pairs was only observable for human agents and not for daily objects, directional arrows, or nonhuman animals. These findings have critical implications for better understanding the scope of human consciousness and the origins of social vision. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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

Fear and disgust have been associated with opposite influences on visual processing, even though both constitute negative emotions that motivate avoidance behavior and entail increased arousal. In the current study, we hypothesized that (a) homeostatic relevance modulates early stages of visual processing, (b) through widespread physiological responses, and that (c) the direction of these modulations depends on whether an emotion calls for immediate regulatory behavior or not. Specifically, we expected that increased arousal should facilitate the detection of fear-related stimuli, and inhibit the detection of disgust-related stimuli. These hypotheses were tested in two preregistered experiments (data collected in 2022, total N = 120, ethnically homogeneous Polish sample). Using a novel, response bias-free version of the breaking continuous flash suppression paradigm, we examined localization and discrimination of fear- and disgust-conditioned stimuli at individually determined perceptual thresholds. Our first hypothesis was confirmed: fear-conditioned stimuli were detected and discriminated better than neutral stimuli, and the magnitude of conditioning-related perceptual preference was related to arousal during conditioning acquisition. In contrast with our second hypothesis, perceptual access to disgust-conditioned stimuli was not diminished. Exploratory analyses suggest that discrimination of disgust-conditioned stimuli was also enhanced, although these effects appeared weaker than those evoked by fear conditioning. The current study strengthens previous evidence for facilitated perception of threatening objects and shows for the first time that stimuli evoking disgust might also gain preferential access to awareness. The results imply that homeostatically relevant stimuli are prioritized by the visual system and that this preference is grounded in the underlying arousal levels. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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

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. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

VWM-based bias in conscious access can be extended to a new sandwich masking task and real-life stimuli.

Previous studies using breaking continuous flash suppression observed that the content of visual working memory (VWM) influences the priority for accessing visual awareness. However, most studies have used simple stimuli, whereas real-life objects are typically more meaningful and contain more perceptual information than simple objects. In this study, we intermixed a delayed match-to-sample task to manipulate the content of VWM, and a breaking repeated masking suppression (b-RMS) task to investigate whether this memory-based effect in conscious access can be extended to a new sandwich masking task and real-life stimuli. The results revealed that memory-congruent objects broke RMS faster than incongruent objects for both simple and real-life objects. Specifically, for simple objects, color-matching targets broke RMS faster than color-mismatching targets, whereas state-matching targets broke RMS faster than state-mismatching targets for real-life objects. These results suggest that the faster detection of VWM-matching over VWM mismatching stimuli-which has been mostly studied using only one type of task (b-CFS) and stimulus (colored shapes)-extends to (1) yet another masking technique (b-RMS) and to (2) a novel stimulus type (real-life objects), providing evidence that memory-based biases in conscious access are a ubiquitous phenomenon.

Unconscious Processing of Greenery in the Tourism Context: A Breaking Continuous Flash Suppression Experiment.

Both tourism and nature have been proven to contribute to people's physical and mental health. Most studies have discussed their positive effects at the conscious level, but the unconscious mechanisms underlying these effects remain under-investigated, especially in the tourism context. Using a psychological experimental paradigm called breaking continuous flash suppression (b-CFS), this study tested how the proportion of greenery in an environment influences people's perceptions of tourism sites and compared the effects of different proportions of greenery on participants' unconscious responses to tourism sites. The results suggest that the presence of greenery improves the participants' unconscious perceptions, and that this effect is due to greenery as an element of the natural world, rather than to green as a color. These findings enhance the understanding of the role that the unconscious response plays in the effect of nature on human health and may have managerial implications for the tourism industry.

Learned value modulates the access to visual awareness during continuous flash suppression

Monetary value enhances visual perception and attention and boosts activity in the primary visual cortex, however, it is still unclear whether monetary value can modulate the conscious access to rewarding stimuli. Here we investigate this issue by employing a breaking continuous flash suppression (b-CFS) paradigm. We measured suppression durations of sinusoidal gratings having orthogonal orientations under CFS in adult volunteers before and after a short session of Pavlovian associative learning in which each orientation was arbitrarily associated either with high or low monetary reward. We found that monetary value accelerated the access to visual awareness during CFS. Specifically, after the associative learning, suppression durations of the visual stimulus associated with high monetary value were shorter compared to the visual stimulus associated with low monetary value. Critically, the effect was replicated in a second experiment using a detection task for b-CFS that was orthogonal to the reward associative learning. These results indicate that monetary reward facilitates the access to awareness of visual stimuli associated with monetary value probably by boosting their representation at the early stages of visual processing in the brain.

Low-level visual processing of motion events as a window into language-specific effects on perception

Abstract This article brings a new perspective to the currently burgeoning interest in the power of language to influence how speakers from different linguistic backgrounds process motion events. While many studies have targeted high-level decision-based processes, such as Manner-based versus Path-based categorisation or motion event similarity judgments from memory, far less is known about the role of various language systems on low-level automatic processing. The goal of this article is to present an experimental method called breaking continuous flash suppression (b-CFS), critically assess its potential to capture language-induced biases when processing motion through a small-scale feasibility study with English native speakers versus Mandarin native speakers, and to provide practical recommendations with examples of how motion event research can respond to the epistemological challenges that this emerging data elicitation method faces.

Surprising Threats Accelerate Conscious Perception.

The folk psychological notion that “we see what we expect to see” is supported by evidence that we become consciously aware of visual stimuli that match our prior expectations more quickly than stimuli that violate our expectations. Similarly, “we see what we want to see,” such that more biologically-relevant stimuli are also prioritised for conscious perception. How, then, is perception shaped by biologically-relevant stimuli that we did not expect? Here, we conducted two experiments using breaking continuous flash suppression (bCFS) to investigate how prior expectations modulated response times to neutral and fearful faces. In both experiments, we found that prior expectations for neutral faces hastened responses, whereas the opposite was true for fearful faces. This interaction between emotional expression and prior expectations was driven predominantly by participants with higher trait anxiety. Electroencephalography (EEG) data collected in Experiment 2 revealed an interaction evident in the earliest stages of sensory encoding, suggesting prediction errors expedite sensory encoding of fearful faces. These findings support a survival hypothesis, where biologically-relevant fearful stimuli are prioritised for conscious access even more so when unexpected, especially for people with high trait anxiety.

Seeing food fast and slow: Arousing pictures and words have reverse priorities in accessing awareness

Previous studies have shown that stimuli triggering higher arousal (e.g., attractiveness) can access awareness faster than those triggering lower arousal, yet no studies have examined the effect of food calories. Since food brings us energy, satiety, and positive emotions, food stimuli bringing higher arousal would likely have higher priority in accessing awareness over those with lower arousal. We used high-calorie and low-calorie food stimuli as representatives for high and low arousal stimuli, respectively, based on the tight relationship between calorie and arousal. By adopting the breaking continuous flash suppression (b-CFS) paradigm, we had high-calorie and low-calorie food pictures or words presented dichoptically with dynamic Mondrian masks and measured the time for food stimuli to be released from suppression. Our results showed that high-calorie food pictures could access visual awareness faster than low-calorie food pictures (Experiment 1), and the reverse pattern was observed for food words (Experiment 2). We ruled out the possibility of the difference in low-level features (Experiment 3) and post-perceptual response bias (Experiment 4) as the causes for the observed b-CFS time differences. This study revealed the dissociation of the unconscious processing of pictures and words, which may rely on mechanisms related to attentional capture. High-arousing stimuli do not always enjoy priority in accessing visual awareness.

Neural and computational processes of accelerated perceptual awareness and decisions: A 7T fMRI study.

Rapidly detecting salient information in our environments is critical for survival. Visual processing in subcortical areas like the pulvinar and amygdala has been shown to facilitate unconscious processing of salient stimuli. It is unknown, however, if and how these areas might interact with cortical regions to facilitate faster conscious perception of salient stimuli. Here we investigated these neural processes using 7T functional magnetic resonance imaging (fMRI) in concert with computational modelling while participants (n = 33) engaged in a breaking continuous flash suppression paradigm (bCFS) in which fearful and neutral faces are initially suppressed from conscious perception but then eventually ‘breakthrough’ into awareness. Participants reported faster breakthrough times for fearful faces compared with neutral faces. Drift‐diffusion modelling suggested that perceptual evidence was accumulated at a faster rate for fearful faces compared with neutral faces. For both neutral and fearful faces, faster response times were associated with greater activity in the amygdala (specifically within its subregions, including superficial, basolateral and amygdalo‐striatal transition area) and the insula. Faster rates of evidence accumulation coincided with greater activity in frontoparietal regions and occipital lobe, as well as the amygdala. A lower decision‐boundary correlated with activity in the insula and the posterior cingulate cortex (PCC), but not with the amygdala. Overall, our findings suggest that hastened perceptual awareness of salient stimuli recruits the amygdala and, more specifically, is driven by accelerated evidence accumulation in fronto‐parietal and visual areas. In sum, we have mapped distinct neural computations that accelerate perceptual awareness of visually suppressed faces.

Biological motion gains preferential access to awareness during continuous flash suppression: Local biological motion matters.

Humans have developed excellent capabilities for the detection of biological motion (BM) that facilitate survival and interpersonal interactions. However, whether and how such capabilities allow BM to access our awareness remain unanswered questions. Therefore, this study aimed to explore these questions across four experiments that relied on the breaking continuous flash suppression paradigm (b-CFS). We found that intact BM, which consists of both global-configuration and local BM information, gained preferential access to awareness compared with inverted BM and non-BM (Experiment 1). Subsequently, we tested two opposing hypotheses regarding factors that modulate the prioritized effect: (a) the global-precedence hypothesis (global configuration plays a major role in BM's preferential access) and (b) the local-precedence hypothesis (local BM information plays a major role in BM's preferential access). The results showed that scrambled BM consisting of only local BM information-but not limited-lifetime BM consisting of global-configuration information and disrupted local BM information-had the same conscious accessibility level as intact BM (Experiment 2). Moreover, scrambled BM-but not limited-lifetime BM-had preferential access to awareness compared with non-BM (Experiment 3). Furthermore, using a reverse-correlation method, we showed that the conscious accessibility of local BM was not governed by a priori body structure (Experiment 4). This study provides substantial evidence that BM gains preferential access to awareness during b-CFS. Moreover, local BM information rather than global configuration plays a major role in conscious accessibility. These findings support the local-precedence hypothesis and suggest that local BM information can serve as a "life detector" in the visual system. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Objects that induce face pareidolia are prioritized by the visual system.

The human visual system has evolved specialized neural mechanisms to rapidly detect faces. Its broad tuning for facial features is thought to underlie the illusory perception of faces in inanimate objects, a phenomenon called face pareidolia. Recent studies on face pareidolia suggest that the mechanisms underlying face processing, at least at the early stages of visual encoding, may treat objects that resemble faces as real faces; prioritizing their detection. In our study, we used breaking continuous flash suppression (b-CFS) to examine whether the human visual system prioritizes the detection of objects that induce face pareidolia over stimuli matched for object content. Similar to previous b-CFS results using real face stimuli, we found that participants detected the objects with pareidolia faces faster than object-matched control stimuli. Given that face pareidolia has been more frequently reported amongst individuals prone to hallucinations, we also explored whether this rapid prioritization is intact in individuals with schizophrenia, and found evidence suggesting that it was. Our findings suggest that face pareidolia engages a broadly tuned mechanism that facilitates rapid face detection. This may involve the proposed fast subcortical pathway that operates outside of visual awareness.

Nasal visual field of origin contributes to interocular competition strength

During binocular rivalry (BR), perceptual dominance alternates between the inputs of the eyes, meaning that (at any time) the non-dominating input is suppressed, despite being projected on a retina. It has been proposed that BR is the result of interocular competition (IOC), where the input that 'wins' the competition becomes the dominant percept. Both top-down factors (e.g., attention, working memory content) and bottom-up factors (e.g., saliency, eye dominance) have been shown to affect IOC. One factor has remained largely disregarded, however: the input’s visual field of origin. The lack of attention to this factor is surprising, since the visual field of origin is known to affect performance in various contexts outside of BR. Exploratory analyses on previously gathered data using a breaking continuous flash suppression (b-CFS) paradigm suggested that nasally presented targets (i.e., presented in the nasal visual hemifield (VHF)) broke through suppression faster than temporally presented targets. We confirmed this exploratory observation in a reanalysis of five independent b-CFS datasets. Strikingly, we found that the effect of VHF was even larger (by 25%) than the well-established effect of eye dominance, as measured by response time differences in the b-CFS paradigm. Importantly, the magnitude of the VHF effect depended on the strength of IOC, both within-observers (recessive > dominant eye), and across-observers (weak > strong eye-dominance). These findings show that the VHF effect reported here is specific to IOC, rather than reflecting a generic visual field anisotropy. Lastly, we simulated 10.000 datasets to show that our findings did not spuriously emerge from our analysis pipeline. Taken together, we demonstrate a substantial advantage for visual input from the nasal VHF during IOC. These findings have broad implications for augmented/virtual reality applications and yield important methodological considerations for researchers utilizing IOC-based paradigms to investigate the contents and functions of human consciousness.

Which comes first? Examining breaking continuous flash suppression time of high-calorie and low-calorie foods

Which comes first? Examining breaking continuous flash suppression time of high-calorie and low-calorie foods

Oxygen Metabolism-induced Stress Response Underlies Heart-brain Interaction Governing Human Consciousness-breaking and Attention.

Neuroscientists have emphasized visceral influences on consciousness and attention, but the potential neurophysiological pathways remain under exploration. Here, we found two neurophysiological pathways of heart-brain interaction based on the relationship between oxygen-transport by red blood cells (RBCs) and consciousness/attention. To this end, we collected a dataset based on the routine physical examination, the breaking continuous flash suppression (b-CFS) paradigm, and an attention network test (ANT) in 140 immigrants under the hypoxic Tibetan environment. We combined electroencephalography and multilevel mediation analysis to investigate the relationship between RBC properties and consciousness/attention. The results showed that RBC function, via two independent neurophysiological pathways, not only triggered interoceptive re-representations in the insula and awareness connected to orienting attention but also induced an immune response corresponding to consciousness and executive control. Importantly, consciousness played a fundamental role in executive function which might be associated with the level of perceived stress. These results indicated the important role of oxygen-transport in heart-brain interactions, in which the related stress response affected consciousness and executive control. The findings provide new insights into the neurophysiological schema of heart-brain interactions.

Sorry, baby: Infant faces reach awareness more slowly than adult faces.

Past research has found an attentional bias for positive relative to neutral stimuli, with a greater attentional bias for stimuli that are more motivationally relevant. Baby faces are an example of a motivationally relevant stimulus because they elicit caretaking behaviors. Building on previous work demonstrating that baby faces capture attention, the current study used breaking continuous flash suppression (bCFS) to investigate whether infant faces are prioritized for access to awareness. On each trial of the task, a face was shown to one eye and a rapidly changing Mondrian pattern to the other. Participants were asked to report the location of the face as soon as it emerged from suppression. The faces were either infant or adult faces, presented in upright or inverted orientation. Despite evidence suggesting that infant faces might reach awareness more quickly than adult faces, the opposite was found: Adult faces reached awareness more quickly than infant faces. Moreover, a stronger face inversion effect was observed for adult versus infant faces, indicating that the shorter suppression times for adult faces were due to increased expertise with adult faces. A past bCFS study demonstrated an own-age face effect for young adults, but it left open the possibility that this effect was due to the youthful appearance of the young versus old faces. The current results rule out this possibility and provide further support for the idea that experience with faces of one's own social group facilitates the access of those faces to awareness. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Unpredictive linguistic verbal cues accelerate congruent visual targets into awareness in a breaking continuous flash suppression paradigm

One of the most influential ideas within the domain of cognition is that of embodied cognition, in which the experienced world is the result of an interplay between an organism’s physiology, sensorimotor system, and its environment. An aspect of this idea is that linguistic information activates sensory representations automatically. For example, hearing the word ‘red’ would automatically activate sensory representations of this color. But does linguistic information prioritize access to awareness of congruent visual information? Here, we show that linguistic verbal cues accelerate matching visual targets into awareness by using a breaking continuous flash suppression paradigm. In a speeded reaction time task, observers heard spoken color labels (e.g., red) followed by colored targets that were either congruent (red), incongruent (green), or neutral (a neutral noncolor word) with respect to the labels. Importantly, and in contrast to previous studies investigating a similar question, the incidence of congruent trials was not higher than that of incongruent trials. Our results show that RTs were selectively shortened for congruent verbal–visual pairings, and that this shortening occurred over a wide range of cue–target intervals. We suggest that linguistic verbal information preactivates sensory representations, so that hearing the word ‘red’ preactivates (visual) sensory information internally.

Sensorimotor predictions shape reported conscious visual experience in a breaking continuous flash suppression task.

Accounts of predictive processing propose that conscious experience is influenced not only by passive predictions about the world, but also by predictions encompassing how the world changes in relation to our actions—that is, on predictions about sensorimotor contingencies. We tested whether valid sensorimotor predictions, in particular learned associations between stimuli and actions, shape reports about conscious visual experience. Two experiments used instrumental conditioning to build sensorimotor predictions linking different stimuli with distinct actions. Conditioning was followed by a breaking continuous flash suppression task, measuring the speed of reported breakthrough for different pairings between the stimuli and prepared actions, comparing those congruent and incongruent with the trained sensorimotor predictions. In Experiment 1, counterbalancing of the response actions within the breaking continuous flash suppression task was achieved by repeating the same action within each block but having them differ across the two blocks. Experiment 2 sought to increase the predictive salience of the actions by avoiding the repetition within blocks. In Experiment 1, breakthrough times were numerically shorter for congruent than incongruent pairings, but Bayesian analysis supported the null hypothesis of no influence from the sensorimotor predictions. In Experiment 2, reported conscious perception was significantly faster for congruent than for incongruent pairings. A meta-analytic Bayes factor combining the two experiments confirmed this effect. Altogether, we provide evidence for a key implication of the action-oriented predictive processing approach to conscious perception, namely that sensorimotor predictions shape our conscious experience of the world.

The neural substrates of subliminal attentional bias and reduced inhibition in individuals with a higher BMI: A VBM and resting state connectivity study

Previous studies have shown that individuals with overweight and obesity may experience attentional biases and reduced inhibition toward food stimuli. However, evidence is scarce as to whether the attentional bias is present even before stimuli are consciously recognized. Moreover, it is not known whether or not differences in the underlying brain morphometry and connectivity may co-occur with attentional bias and impulsivity towards food in individuals with different BMIs. To address these questions, we asked fifty-three participants (age M = 23.2, SD = 2.9, 13 males) to perform a breaking Continuous Flash Suppression (bCFS) task to measure the speed of subliminal processing, and a Go/No-Go task to measure inhibition, using food and nonfood stimuli. We collected whole-brain structural magnetic resonance images and functional resting-state activity. A higher BMI predicted slower subliminal processing of images independently of the type of stimulus (food or nonfood, p = 0.001, εp2 = 0.17). This higher threshold of awareness is linked to lower grey matter (GM) density of key areas involved in awareness, high-level sensory integration, and reward, such as the orbitofrontal cortex [t = 4.55, p = 0.003], the right temporal areas [t = 4.18, p = 0.002], the operculum and insula [t = 4.14, p = 0.005] only in individuals with a higher BMI. In addition, individuals with a higher BMI exhibit a specific reduced inhibition to food in the Go/No-Go task [p = 0.02, εp2 = 0.02], which is associated with lower GM density in reward brain regions [orbital gyrus, t = 4.97, p = 0.005, and parietal operculum, t = 5.14, p < 0.001] and lower resting-state connectivity of the orbital gyrus to visual areas [fusiform gyrus, t = -4.64, p < 0.001 and bilateral occipital cortex, t = -4.51, p < 0.001 and t = -4.34, p < 0.001]. Therefore, a higher BMI is predictive of non food-specific slower visual subliminal processing, which is linked to morphological alterations of key areas involved in awareness, high-level sensory integration, and reward. At a late, conscious stage of visual processing a higher BMI is associated with a specific bias towards food and with lower GM density in reward brain regions. Finally, independently of BMI, volumetric variations and connectivity patterns in different brain regions are associated with variability in bCFS and Go/No-Go performances.