Perception-action Dissociations as a Window into Consciousness.

Understanding the neural correlates of unconscious perception stands as a primary goal of experimental research in cognitive psychology and neuroscience. In this Perspectives paper, we explain why experimental protocols probing qualitative dissociations between perception and action provide valuable insights into conscious and unconscious processing, along with their corresponding neural correlates. We present research that utilizes human eye movements as a sensitive indicator of unconscious visual processing. Given the increasing reliance on oculomotor and pupillary responses in consciousness research, these dissociations also provide a cautionary tale about inferring conscious perception solely based on no-report protocols.

How (not) to demonstrate unconscious priming: Overcoming issues with post-hoc data selection, low power, and frequentist statistics.

One widely used scientific approach to studying consciousness involves contrasting conscious operations with unconscious ones. However, challenges in establishing the absence of conscious awareness have led to debates about the extent and existence of unconscious processes. We collected experimental data on unconscious semantic priming, manipulating prime presentation duration to highlight the critical role of the analysis approach in attributing priming effects to unconscious processing. We demonstrate that common practices like post-hoc data selection, low statistical power, and frequentist statistical testing can erroneously support claims of unconscious priming. Conversely, adopting best practices like direct performance-awareness contrasts, Bayesian tests, and increased statistical power can prevent such erroneous conclusions. Many past experiments, including our own, fail to meet these standards, casting doubt on previous claims about unconscious processing. Implementing these robust practices will enhance our understanding of unconscious processing and shed light on the functions and neural mechanisms of consciousness.

Prime-induced illusion of control: The influence of unconscious priming on self-initiated actions and the role of regression to the mean.

To what degree human cognition is influenced by subliminal stimuli is a controversial empirical question. One striking example was reported by Linser and Goschke (2007): participants overestimated how much control they had over objectively uncontrollable stimuli when masked congruent primes were presented immediately before the action. Critically, however, unawareness of the masked primes was established by post hoc data selection. In our preregistered study we sought to explore these findings while adjusting prime visibility based on individual thresholds, so that each participant underwent both visible and non-visible conditions. In experiment 1, N = 39 participants engaged in a control judgement task: following the presentation of a semantic prime, they freely selected between two keys, which triggered the appearance of a colored circle. The color of the circles, however, was independent of the key-press. Subsequently, participants assessed their perceived control over the circle's color, based on their key-presses, via a rating scale that ranged from 0 % (no control) to 100 % (complete control). Contrary to Linser and Goschke (2007)'s findings, this experiment demonstrated that predictive information influenced the experience of agency only when primes were consciously processed. In experiment 2, utilizing symbolic (arrow) primes, N = 35 participants had to rate their feeling of control over the effect-stimulus' identity during a two-choice identification paradigm (i.e., they were instructed to press a key corresponding to a target stimulus; with a contingency between target and effect stimulus of 75 %/25 %). The results revealed no significant influence of subliminal priming on agency perceptions. In summary, this study implies that unconscious stimuli may not exert a substantial influence on the conscious experience of agency, underscoring the need for careful consideration of methodological aspects and experimental design's impact on observed phenomena.

Prior conscious experience modulates the impact of audiovisual temporal correspondence on unconscious visual processing.

Conscious visual experiences are enriched by concurrent auditory information, implying audiovisual interactions. In the present study, we investigated how prior conscious experience of auditory and visual information influences the subsequent audiovisual temporal integration under the surface of awareness. We used continuous flash suppression (CFS) to render perceptually invisible a ball-shaped object constantly moving and bouncing inside a square frame window. To examine whether audiovisual temporal correspondence facilitates the ball stimulus to enter awareness, the visual motion was accompanied by click sounds temporally congruent or incongruent with the bounces of the ball. In Experiment 1, where no prior experience of the audiovisual events was given, we found no significant impact of audiovisual correspondence on visual detection time. However, when the temporally congruent or incongruent bounce-sound relations were consciously experienced prior to CFS in Experiment 2, congruent sounds yielded faster detection time compared to incongruent sounds during CFS. In addition, in Experiment 3, explicit processing of the incongruent bounce-sound relation prior to CFS slowed down detection time when the ball bounces became later congruent with sounds during CFS. These findings suggest that audiovisual temporal integration may take place outside of visual awareness though its potency is modulated by previous conscious experiences of the audiovisual events. The results are discussed in light of the framework of multisensory causal inference.

The role of identity priming on the (unconscious) bodily self-attribution.

It has been recently demonstrated that hand stimuli presented in a first-, with respect to a third-, person perspective were prioritized before awareness independently from their identity (i.e., self, or other). This pattern would represent an unconscious advantage for self-related bodily stimuli rooted in spatial perspective. To deeper investigate the role of identity, we employed a breaking-Continuous Flash Suppression paradigm in which a self- or other-hand presented in first- or third-person perspective was displayed after a conscious identity-related prime (i.e., self or other face). We replicated the unconscious advantage of the first-person perspective but, crucially, we reported that within the first-person perspective, other-hand stimuli preceded by other-face priming slowed down the conscious access with respect to the other conditions. These findings demonstrate that a top-down conscious identity context modulates the unconscious self-attribution of bodily stimuli. Within a predictive processing framework, we suggest that, by adding ambiguous information, the prime forces a prediction update that slows conscious access.

Temporal windows of unconscious processing cannot easily be disrupted.

Conscious perception is preceded by long periods of unconscious processing. These periods are crucial for analyzing temporal information and for solving the many ill-posed problems of vision. An important question is what starts and ends these windows and how they may be interrupted. Most experimental paradigms do not offer the methodology required for such investigation. Here, we used the sequential metacontrast paradigm, in which two streams of lines, expanding from the center to the periphery, are presented, and participants are asked to attend to one of the motion streams. If several lines in the attended motion stream are offset, the offsets are known to integrate mandatorily and unconsciously, even if separated by up to 450 ms. Using this paradigm, we here found that external visual objects, such as an annulus, presented during the motion stream, do not disrupt mandatory temporal integration. Thus, if a window is started once, it appears to remain open even in the presence of disruptions that are known to interrupt visual processes normally. Further, we found that interrupting the motion stream with a gap disrupts temporal integration but does not terminate the overall unconscious processing window. Thus, while temporal integration is key to unconscious processing, not all stimuli in the same processing window are integrated together. These results strengthen the case for unconscious processing taking place in windows of sensemaking, during which temporal integration occurs in a flexible and perceptually meaningful manner.

Does response inhibition occur unconsciously? A systematic review and Bayesian meta-analysis.

Consciousness is traditionally considered necessary for response inhibition. Recently, researchers have attempted to explore unconscious response inhibition using the masked go/no-go task. However, their findings were controversial and might have been confounded by the methodology employed. Therefore, we used a three-level Bayesian meta-analysis to provide the first systematic overview of the field of unconscious response inhibition. Finally, 34 studies in 16 articles with a total sample size of 521 were included. In summary, we found only inconclusive evidence of a reaction time slowing effect after excluding studies with conscious no-go experience (mean difference = 8.47 ms, BF10 = 2.71). In addition, the overall effect size of the difference in sensitivity to masked stimuli between the masked go/no-go task and the objective awareness task was small and uncertain (mean difference = 0.09, BF10 = 2.39). Taken together, these findings indicate a lack of solid evidence for the occurrence of unconscious response inhibition. Our findings do not oppose the possibility of unconscious response inhibition, but rather emphasize the need for more rigorous research methodologies in this field.

'A Home to the Lie': The Contemporary (Per)version of Truth.

This paper explores the contemporary trend towards relativization and perversion of truth increasingly prominent in American culture, which, in Bion's terminology (1970), has become an ever more hospitable "home to the lie." The anti-COVID vaccine movement emerging in the United States in 2021, and its related network of conspiracy theories, is presented as an example. To make sense of these phenomena the author presents clinical vignettes illustrating (1) Bion's (1970) notions of catastrophic change, the lie/thinker relation, and the messianic idea; (2) Freud's (1921) thinking on group leaders; and (3) Matte-Blanco's (1975) bi-logical theory of mind. According to Bion, the lie is mobilized to avoid the psychological upheaval associated with catastrophic change. The author suggests that developments in American life experienced as threatening catastrophic change provide a hospitable environment for the lie, making the recognition of truth more elusive. In line with Matte-Blanco's bi-logical theory, the author suggests that creation of opportunities for dialogue giving weight to both conscious and unconscious ways of thinking is necessary for re-establishing a culture of truth.

Fetal Fantasy and the Perfect Child: How Certain Challenges of Adolescence may Inform Aspects of the Abortion Debate.

This article explores psychic aspects of abortion, from the fixity of beliefs over its legalization, to conscious and unconscious fantasies related to the fetus, children, parenting, fertility, and so on. Generally speaking, the field has shown less direct interest in abortion per se than might be surmised, particularly given the centrality of sexuality and procreation in psychoanalysis. The recent legal changes may initiate more psychoanalytic interest in the topic. The current writing studies a possible strand of fantasy in which conscious and unconscious wishes for an unending, idealized, and blameless child-object are displaced onto a fetus or fetal imago. Speculations and suggestions are drawn from casework with an individual which points to a possible channeling or avoidance of unprocessed grief when the seeming perfection of childhood ends abruptly, almost without transition, with the imposition of adolescent personality development.

Raw Object Identification.

This paper attempts to deal with a specific kind of pathological identification-"raw object identification"-which tends to appear as concrete physiological phenomena, trying to escape meaning and integration. These somatic manifestations stem from early traumatic experiences with a meaningful object and entrap-as revealed through analysis-specific significant qualities of that object. A massive splitting ensues between body and mind, self and object, relation and identification. Certain properties of the object are then experienced as a foreign body in the subject and are defensively identified with. Thus, raw object identification is often manifested in stubborn bodily symptoms.

The Need to Mitigate Unconscious Bias to Improve Sponsorship Opportunities for Underrepresented Faculty in Academic Radiology.

Women physicians and those from racial and ethnic groups underrepresented in medicine face unique barriers to career advancement in academic medicine, especially in specialties that lack diversity such as radiology. One such barrier is the effect of unconscious bias on the ability of faculty from these groups to find effective sponsors. Given the central role of sponsorship in career advancement, departments are called on to implement formal sponsorship programs to address inequities stemming from bias.

Neural mechanisms of response priming do not support veridical unconscious processing.

Studies using the priming paradigm often infer that unconscious processes have more veridical access to the world than conscious processes. These interpretations are based on a standard reasoning that erroneously infers good sensitivity of indirect measures from a clear priming effect. To correct for this fallacy, researchers should explicitly compute the sensitivities from indirect measures and compare them against the sensitivities of direct measures. Recent results suggest that indirect behavioral measures are not more sensitive than direct measures and challenge interpretations about veridical unconscious processing. We add to these behavioral results by focusing on neurophysiological indirect measures. In two EEG experiments, we investigate whether event related potentials (ERPs) are more sensitive to different visual stimuli than direct measures. The results show the opposite effect: higher sensitivities for direct than indirect measures. Therefore-contrasting commonly held belief-we find no evidence for more veridical unconscious than conscious processes in ERP measures.

Evidence for a minimal role of stimulus awareness in reversal of threat learning.

In an ever-changing environment, survival depends on learning which stimuli represent threat, and also on updating such associations when circumstances shift. It has been claimed that humans can acquire physiological responses to threat-associated stimuli even when they are unaware of them, but the role of awareness in updating threat contingencies remains unknown. This complex process-generating novel responses while suppressing learned ones-relies on distinct neural mechanisms from initial learning, and has only been shown with awareness. Can it occur unconsciously? Here, we present evidence that threat reversal may not require awareness. Participants underwent classical threat conditioning to visual stimuli that were suppressed from awareness. One of two images was paired with an electric shock; halfway through the experiment, contingencies were reversed and the shock was paired with the other image. Despite variations in suppression across participants, we found that physiological responses reflected changes in stimulus-threat pairings independently of stimulus awareness. These findings suggest that unconscious affective processing may be sufficiently flexible to adapt to changing circumstances.

Self-constitution and "Infrastructural" Change: An Interdisciplinary Account of Psychoanalytic Action.

Beyond revealing unconscious pathological identifications and traits-including their past usefulness but current toxicity-what techniques in our psychoanalytic practice can lead to change? Radically different from mainstream philosophical views advocating that such undesirable self-aspects should not be endorsed as Self, psychoanalysts hold that these negative traits must instead be understood as part of one's Self. But then what? Investigating concepts from classical conditioning, neuroscience, the philosophy of mind and action, and psychoanalytic practice itself, this article will suggest a preliminary account of the mechanism of action of psychoanalytic work after insight.

How expectations of pain elicited by consciously and unconsciously perceived cues unfold over time.

Expectation can shape the perception of pain within a fraction of time, but little is known about how perceived expectation unfolds over time and modulates pain perception. Here, we combine magnetoencephalography (MEG) and machine learning approaches to track the neural dynamics of expectations of pain in healthy participants with both sexes. We found that the expectation of pain, as conditioned by facial cues, can be decoded from MEG as early as 150 ms and up to 1100 ms after cue onset, but decoding expectation elicited by unconsciously perceived cues requires more time and decays faster compared to consciously perceived ones. Also, results from temporal generalization suggest that neural dynamics of decoding cue-based expectation were predominately sustained during cue presentation but transient after cue presentation. Finally, although decoding expectation elicited by consciously perceived cues were based on a series of time-restricted brain regions during cue presentation, decoding relied on the medial prefrontal cortex and anterior cingulate cortex after cue presentation for both consciously and unconsciously perceived cues. These findings reveal the conscious and unconscious processing of expectation during pain anticipation and may shed light on enhancing clinical care by demonstrating the impact of expectation cues.

Interactions between Conscious and Subconscious Signals: Selective Attention under Feature-Based Competition Increases Neural Selectivity during Brain Adaptation.

Efficient perception in natural environments depends on neural interactions between voluntary processes within cognitive control, such as attention, and those that are automatic and subconscious, such as brain adaptation to predictable input (also called repetition suppression). Although both attention and adaptation have been studied separately and there is considerable knowledge of the neurobiology involved in each of these processes, how attention interacts with adaptation remains equivocal. We examined how attention interacts with visual and auditory adaptation by measuring neuroimaging effects consistent with changes in either neural gain or selectivity. Male and female human participants were scanned with functional magnetic resonance imaging (fMRI) first while they discriminated repetition of morphed faces or voices and either directed their attention to stimulus identity or spatial location. Attention to face or voice identity, while ignoring stimulus location, solely increased the gain of respectively face- or voice-sensitive cortex. The results were strikingly different in an experiment when participants attended to voice identity versus stimulus loudness. In this case, attention to voice while ignoring sound loudness increased neural selectivity. The combined results show that how attention affects adaptation depends on the level of feature-based competition, reconciling prior conflicting observations. The findings are theoretically important and are discussed in relation to neurobiological interactions between attention and different types of predictive signals.SIGNIFICANCE STATEMENT Adaptation to repeated environmental events is ubiquitous in the animal brain, an automatic typically subconscious, predictive signal. Cognitive influences, such as by attention, powerfully affect sensory processing and can overcome brain adaptation. However, how neural interactions occur between adaptation and attention remains controversial. We conducted fMRI experiments regulating the focus of attention during adaptation to repeated stimuli with perceptually balanced stimulus expectancy. We observed an interaction between attention and adaptation consistent with increased neural selectivity, but only under conditions of feature-based competition, challenging the notion that attention interacts with brain adaptation by only affecting response gain. This demonstrates that attention retains its full complement of mechanistic influences on sensory cortex even as it interacts with more automatic or subconscious predictive processes.

Pupil-Linked Arousal Responds to Unconscious Surprisal.

Pupil size under constant illumination reflects brain arousal state, and dilates in response to novel information, or surprisal. Whether this response can be observed regardless of conscious perception is still unknown. In the present study, male and female adult humans performed an implicit learning task across a series of three experiments. We measured pupil and brain-evoked potentials to stimuli that violated transition statistics but were not relevant to the task. We found that pupil size dilated following these surprising events, in the absence of awareness of transition statistics, and only when attention was allocated to the stimulus. These pupil responses correlated with central potentials, evoking an anterior cingulate origin. Arousal response to surprisal outside the scope of conscious perception points to the fundamental relationship between arousal and information processing and indicates that pupil size can be used to track the progression of implicit learning.SIGNIFICANCE STATEMENT Pupil size dilates following increase in mental effort, surprise, or more generally global arousal. However, whether this response arises as a conscious response or reflects a more fundamental mechanism outside the scrutiny of awareness is still unknown. Here, we demonstrate that unexpected changes in the environment, even when processed unconsciously and without being relevant to the task, lead to an increase in arousal levels as reflected by the pupillary response. Further, we show that the concurrent electrophysiological response shares similarities with mismatch negativity, suggesting the involvement of anterior cingulate cortex. All in all, our results establish novel insights about the mechanisms driving global arousal levels, and it provides new possibilities for reliably measuring unconscious processes.

Unconscious semantic priming from pictures under backward masking and continuous flash suppression.

It is debated whether the meaning of invisible pictures can be processed unconsciously. We tested whether pictures of animals or objects presented under backward masking or continuous flash suppression could prime the subsequent categorization of target words into animal or non-animal. In Experiment 1, the backward masking part failed to replicate the priming effect reported in two previous studies, despite sufficient statistical power (N = 59). Similarly, the continuous flash suppression part provided no evidence for a priming effect. In Experiment 2 (N = 65) we shortened the prime-target SOA from 290 ms to 90 ms, but again failed to obtain unconscious semantic priming under backward masking. Thus, our study did not provide evidence for unconscious semantic processing of pictures. These findings support the emerging view that unconscious processing is rather limited in scope.

Forcing you to experience wonder: Unconsciously biasing people's choice through strategic physical positioning.

Magicians have developed powerful tools to covertly force a spectator to choose a specific card. We investigate the physical location force, in which four cards (from left to right: 1-2-3-4) are placed face-down on the table in a line, after which participants are asked to push out one card. The force is thought to rely on a behavioural bias in that people are more likely to choose the third card from their left. Participants felt that their choice was extremely free, yet 60% selected the 3rd card. There was no significant difference in estimates and feelings of freedom between those who chose the target card (i.e. 3rd card) and those who selected a different card, and they underestimated the actual proportion of people who selected the target card. These results illustrate that participants' behaviour was heavily biased towards choosing the third card, but were oblivious to this bias.

Masked blindsight in normal observers: Measuring subjective and objective responses to two features of each stimulus.

Recent visual masking studies that have measured visual awareness with graded subjective scales have often failed the show any evidence for unconscious visual processing in normal observers in a paradigm similar to that used in studies on blindsight patients. Without any reported awareness of the target, normal observers typically cannot discriminate target's features better than chance. The present study examined processing of color and orientation by measuring graded awareness and forced-choice discriminations for both features in each trial. When no awareness for either feature was reported, discrimination of each feature succeed better than expected by chance, even when the other feature was incorrectly discriminated in the same trial. However, the characteristics of the mask determined whether or not masked blindsight was observed. We conclude that when the processing channels are free from intra-channel interference, unbound or weakly bound features can guide behaviour without any reported awareness in normal observers.