Awareness Of Stimuli Research Articles

Neurocognitive hacking A new capability in cyber conflict?

This article presents a discussion of neurocognitive hacking and its potential for use at the strategic, operational, and tactical levels of cyber conflict. Neurocognitive hacking refers to the ability to activate specific neural areas of the brain, via subliminal or supraliminal stimuli, to shape the behavioral outcomes of an adversary. Research suggests that awareness of mortality-related stimuli has neural correlates in the right amygdala and left anterior cingulate cortex and mediates negative behavior toward out-group members, including unconscious discriminatory behavior. Given its in-group/out-group dynamic, the phenomenon could be exploited for use in information operations toward target populations, specifically ones that are multiethnic, multicultural, or multireligious. Although development of the theoretical framework behind neurocognitive hacking is ongoing, mortality-related stimuli are proposed to activate one's unconscious vigilance system to further evaluate the locus and viability of the suspect stimuli. Research suggests that the subsequent discriminatory affective reactions directed toward out-group members are representative of automatic heuristics evolved to protect the organism in the event a stimulus represents a more serious threat to survival. Therefore, presenting mortality-related stimuli over computer networks to targeted audiences may facilitate the ingestion of tailored propaganda or shaping of specific behavioral outcomes within a population, including sowing division in a target community or weakening support for a specific political regime.

A single bout of vigorous-intensity aerobic exercise affects reactive, but not proactive cognitive brain functions

The literature on aerobic exercise and neurocognition reports acute post-exercise enhancement of neural activity linked to motor preparation in the premotor area and inhibitory control in the frontoparietal areas. However, the acute effect of vigorous-intensity aerobic exercise (VIAE) on the prefrontal, the insular, and the occipito-parietal activities linked to proactive control, early perceptual, and attentional processing is indeterminate. Thus, the present study investigated the acute effect of VIAE on the neurobehavioral correlates of these proactive and reactive neurocognitive functions. Young, healthy subjects participated in two separate experimental sessions: 30 min of VIAE and 30 min of internet browsing. Before and immediately after the two sessions, we recorded high-resolution electroencephalograms while performing a visuomotor discriminative response task. For testing the effect of VIAE on cognitive processing, we analyzed the behavioral performance and event-related potentials (ERPs). The analysis of behavioral data did not reveal any VIAE effect on task performance. The analysis of ERPs showed no significant VIAE effect on the proactive functions in the premotor and the prefrontal areas, but significant effects on the reactive functions related to selective attention in parietal areas (indexed by the N1 amplitude) and perceptual awareness in the anterior insula (indexed by the pN1 latency). We concluded that a single bout of VIAE does not affect the proactive functions in the premotor and the prefrontal areas, but modulates the early reactive neural mechanisms underlying perceptual awareness of stimuli in the insular cortex and selective attention in the parieto-occipital areas.

How to operationalise consciousness

ObjectiveTo review the way consciousness is operationalised in contemporary research, discuss strengths and weaknesses of current approaches and propose new measures.MethodWe first reviewed the literature pertaining to the phenomenal character of visual and self‐consciousness as well as awareness of visual stimuli. We also reviewed more problematic cases of dreams and animal consciousness, specifically that of octopuses.ResultsDespite controversies, work in visual and self‐consciousness is highly developed and there are notable successes. Cases where experiences are not induced, such as dreams, and where no verbal report is possible, such as when we study purported experiences of octopuses, are more challenging. It is difficult to be confident about the reliability and validity of operationalisations of dreams. Although this is a general concern about the measuring consciousness, it is not a sufficiently severe concern to completely undermine the work reviewed on vision and self‐consciousness. It is more difficult to see how the good work on human psychology can be applied to non‐human animals, especially those with radically different nervous systems, such as octopuses. Given the limitations of report‐based operationalisations of consciousness, it is desirable to develop non‐report‐based measures, particularly for phenomenal qualities. We examine a number of possibilities and offer two possible approaches of varying degrees of practicality, the first based on combining quality space descriptions of phenomenal qualities and the notion of a “neural activation space” inherited from connectionist A.I., the second being a novel match to target approach.ConclusionConsciousness is a multi‐faceted phenomenon and requires a variety of operationalisations to be studied.

Body Dissatisfaction Enhances Awareness and Facilitates the Consolidation of Body-Related Words During Rapid Serial Visual Presentation.

Attentional biases have received considerable focus in research on cognitive biases and body dissatisfaction (BD). However, most work has focused on spatial allocation of attention. The current two experiments employed a rapid serial visual presentation (RSVP) task to investigate attention bias to body-related words in the temporal domain among young females with high and low BD. During this task, there were two targets presented in the same stimulus stream. The first target was defined as target one (T1) and the second was defined as target 2 (T2). Participants were asked to identify T2 while ignoring T1 in single task mode or identify both targets in the dual task mode. In the current study, Experiment 1 assessed the stimulus-driven attention of body-related stimuli. Participants were required to identify a target of neutral word (T2) as quickly and accurately as possible while ignoring the preceding target (T1) of neutral, fat-, or thin-related words. As expected, we observed spontaneous attentional blink (AB) effects elicited by both fat- and thin-related T1s among participants with high BD, suggesting enhanced awareness of body-related stimuli even when this information does not have to be identified. Such effects did not emerge among participants without BD. Experimental 2 investigated the goal-directed attention of body-related stimuli, during which participants needed to identify both the T1 and neutral T2. Participants with BD showed reduced AB effects after both fat- and thin-related T1, suggesting facilitated consolidation of body-related information in goal-directed attention among participants with BD. These findings have important clinical implications that it provided insight for creating more accurate attention bias modification (ABM) task aiming at reducing and preventing BD among young females.

Motor response influences perceptual awareness judgements.

What is the relation between perceptual awareness and action? In this study we tested the hypothesis that motor response influences perceptual awareness judgements. We used a perceptual discrimination task in which presentation of the stimulus was immediately followed by a cue requiring a motor response that was irrelevant to the task but could be the same, opposite, or neutral to the correct response to the stimulus. After responding to the cue, participants rated their stimulus awareness using the Perceptual Awareness Scale, and then carried out their discrimination response. Participants reported a higher level of stimulus awareness after carrying out responses that were either congruent or incongruent with the response required by the stimulus, compared to the neutral condition. The results suggest that the motor response overlapping with a potential response to the stimulus provides information about the outcome of decision process and increases the reported awareness of stimuli.

Clinical efficacy of a combined acceptance and commitment therapy, dialectical behavioural therapy, and functional analytic psychotherapy intervention in patients with borderline personality disorder.

Borderline personality disorder (BPD) consists of a persistent pattern of instability in affective regulation, impulse control, interpersonal relationships, and self-image. Although certain forms of psychotherapy are effective, their effects are small to moderate. One of the strategies that have been proposed to improve interventions involves integrating the therapeutic elements of different psychotherapy modalities from a contextual behavioural perspective (ACT, DBT, and FAP). Patients (n=65) attending the BPD Clinic of the Instituto Nacional de Psiquiatría Ramón de la Fuente Muñíz in Mexico City who agreed to participate in the study were assigned to an ACT group (n=22), a DBT group (n=20), or a combined ACT+DBT+FAP therapy group (n=23). Patients were assessed at baseline and after therapeutic trial on measures of BPD symptom severity, emotion dysregulation, experiential avoidance, attachment, control over experiences, and awareness of stimuli. ANOVA analyses showed no differences between the three therapeutic groups in baseline measures. Results of the MANOVA model showed significant differences in most dependent measures over time but not between therapeutic groups. Three modalities of brief, contextual behavioural therapy proved to be useful in decreasing BPD symptom severity and emotional dysregulation, as well as negative interpersonal attachment. These changes were related to the reduction of experiential avoidance and the acquisition of mindfulness skills in all treatment groups, which may explain why no differences between the three different intervention modalities were observed. Brief adaptations of acceptance and commitment therapy and dialectical behavioural therapy are effective interventions for BPD patients, in combined or isolated modalities, and with or without the inclusion of functional analytic psychotherapy. The reduction of experiential avoidance and the acquisition of mindfulness skills are related with the diminution of BPD symptoms severity, including emotional dysregulation and negative interpersonal attachment.

Neural basis of somatosensory target detection independent of uncertainty, relevance, and reports.

Research on somatosensory awareness has yielded highly diverse findings with putative neural correlates ranging from activity within somatosensory cortex to activation of widely distributed frontoparietal networks. Divergent results from previous studies may reside in cognitive processes that often coincide with stimulus awareness in experimental settings. To scrutinise the specific relevance of regions implied in the target detection network, we used functional magnetic resonance imaging (n = 27) on a novel somatosensory detection task that explicitly controls for stimulus uncertainty, behavioural relevance, overt reports, and motor responses. Using Bayesian Model Selection, we show that responses reflecting target detection are restricted to secondary somatosensory cortex, whereas activity in insular, cingulate, and motor regions is best explained in terms of stimulus uncertainty and overt reports. Our results emphasise the role of sensory-specific cortex for the emergence of perceptual awareness and dissect the contribution of the frontoparietal network to classical detection tasks.

Auditory affective processing requires awareness.

Recent work has challenged the previously widely accepted belief that affective processing does not require awareness and can be carried out with more limited resources than semantic processing. This debate has focused exclusively on visual perception, even though evidence from both human and animal studies suggests that existence for nonconscious affective processing would be physiologically more feasible in the auditory system. Here we contrast affective and semantic processing of nonverbal emotional vocalizations under different levels of awareness in three experiments, using explicit (two-alternative forced choice masked affective and semantic categorization tasks, Experiments 1 and 2) and implicit (masked affective and semantic priming, Experiment 3) measures. Identical stimuli and design were used in the semantic and affective tasks. Awareness was manipulated by altering stimulus-mask signal-to-noise ratio during continuous auditory masking. Stimulus awareness was measured on each trial using a four-point perceptual awareness scale. In explicit tasks, neither affective nor semantic categorization could be performed in the complete absence of awareness, while both tasks could be performed above chance level when stimuli were consciously perceived. Semantic categorization was faster than affective evaluation. When the stimuli were partially perceived, semantic categorization accuracy exceeded affective evaluation accuracy. In implicit tasks neither affective nor semantic priming occurred in the complete absence of awareness, whereas both affective and semantic priming emerged when participants were aware of the primes. We conclude that auditory semantic processing is faster than affective processing, and that both affective and semantic auditory processing are dependent on awareness. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The effects of working memory load on visual awareness and its electrophysiological correlates

Consciousness and working memory (WM) have been thought to be closely related, but their exact relationship has remained unclear. The present study focused on the question whether visual awareness, the subjective experience of seeing, depends on resources of WM. Three dual-task experiments were run. The participants were asked to report their awareness of a low-contrast target stimulus while their WM was loaded by a requirement to concurrently maintain verbal information (Experiment 1) or visuo-spatial information (Experiment 2) in WM, or by a concurrent executive task (Experiment 3). Behavioral responses and event-related brain potential (ERP) correlates of visual awareness in response to the targets were examined. Experiments 1 and 2 revealed that maintenance of information in WM did not have any effect on reported visual awareness and its electrophysiological correlates. Experiment 3 found that executive load decreased reported visual awareness, which was reflected in ERPs around 350–550 ms after stimulus onset as a reduction in the amplitudes of P3 to detected stimuli. The earlier, posterior correlate of visual awareness in N200 time window (180–280 ms) was not affected by load in any of the conditions. The results suggest that visual consciousness and WM share resources at a relatively late stage of conscious processing, which involves active manipulation of contents. The findings are in line with a recent view suggesting that a posterior “hot zone” is responsible for visual awareness, while frontal regions contribute to higher-level cognitive processes that occur after visual awareness has arisen.

The relation of discrete stimuli can be integrated despite the failure of conscious identification

ABSTRACTThe integration of the sameness or difference of two unconscious stimuli occurs and affects behaviour without subjective visual consciousness. Yet, intermittent stimulus awareness or a process simpler than integration could also account for these results. In a masked go/no-go task, participants provided or withheld a response based on the same/different relation of two stimuli. Post-trial performance on a discrimination task was used to classify invisible stimuli, providing an objective criterion of awareness. Stimulus pairs with a No-go-associated relation showed reduced and slower responding even when those stimuli were incorrectly discriminated and presumably unconscious. Due to the large set of stimuli, this effect is unlikely to be due to response mapping or action triggers. The integration of the relation of discrete stimuli is a cognitive function that is not dependent upon visual awareness, in the form of conscious identification, to occur.

Visual scanning behavior during distracted walking in healthy young adults

BackgroundAn epidemic of pedestrian accidents when walking while texting suggests that people are less aware of their surroundings during distracted walking, and highlights the importance of visual scanning for pedestrian safety. Quantitative examination of visual scanning during distracted walking is still lacking. Research questionIs visual scanning behavior altered by distracted walking in healthy young adults? MethodsWe compared visual scanning behavior in 20 young adults during usual (single-task) walking, walking while performing a letter-fluency task, and walking while texting. Visual scanning behavior was measured by fixation count and dwell time percentage in specific areas of interest. Dual-task effects on gait speed, letter fluency, texting speed and accuracy, and situational awareness were also examined. ResultVisual scanning behavior differed between the three walking conditions. During dual-task letter fluency, participants had significantly more non-walking path fixations than either of the other two conditions (i.e., more frequent, broader visual scanning). Conversely, during dual-task texting, gaze was focused predominantly on the phone, with little visual scanning of the walking path and surrounding environment. When walking without texting or talking, gaze was directed equally to far walking path and surrounding environment. SignificanceTexting while walking is associated with a considerable reduction in overt visual attention to the walking path and surrounding areas. Whether this translates to reduced conscious awareness of environmental stimuli remains unclear. Performing a verbal task while walking was associated with more frequent, wider visual scanning behavior, which may be specific to the nature of the verbal task in this study.

Memory awareness disruptions in amnestic mild cognitive impairment: comparison of multiple awareness types for verbal and visuospatial material

ABSTRACTSuccessful memory is normally accompanied by explicit awareness of retrieval and confidence in the accuracy of the retrieval product. Prior findings suggest that these features of metamemory can be dissociated from retrieval accuracy in Amnestic Mild Cognitive Impairment (aMCI). However, the literature on this question contains variable and conflicting results, likely because of differences in experimental conditions. We sought to systematically evaluate memory awareness disruptions in aMCI using multiple measures and stimulus formats within the same individuals. Memory awareness was tested with global predictions and postdictions, judgments of learning, confidence level ratings, and modified feeling-of-knowing ratings in tasks of visuospatial and verbal memory. These tests were administered to 14 individuals with aMCI and 15 healthy, age-matched controls. Memory awareness accuracy was calculated as the correspondence between subjective judgments and memory performance.Individuals with aMCI demonstrated impaired global and trial-level retrospective task awareness for visuospatial and verbal stimuli. Additionally, modified feeling-of-knowing awareness was impaired selectively for verbal stimuli. Statistical effect sizes for global awareness impairments were comparable to impairments in several objective neuropsychological memory assessments.Memory awareness (metamemory) disruptions in aMCI were most evident for a subset of subjective judgment types and task input modalities. These findings advance understanding of the nature of memory impairments in aMCI and support the utility of incorporating memory awareness testing to better characterize memory integrity in older adults.

Influence of continuous flash suppression mask frequency on stimulus visibility

The continuous flash suppression (CFS) paradigm is increasingly used in consciousness research, but its mechanisms are still not fully understood. To better understand its temporal properties, we presented the CFS masks at 9 frequencies, and examined their influence on stimuli visibility, while taking into account the inter-individual variability and the change of CFS suppression as the experiment progressed. The frequencies consisted of fundamental frequencies of 3, 4 and 5 Hz, and their 2nd and 3rd harmonics, which included the 10 Hz frequency typically used in most of the CFS studies. We found that the suppression of stimulus awareness was stronger under 4, 6 and 8 Hz than 10 Hz. After controlling for inter-individual variability with mixed-effects analysis, we found that the number of seen trials was lower for the 4 Hz-basis frequencies than the 5 Hz ones, and was lower for the 2nd than 3rd harmonic. We propose that this may be caused by an interaction between the CFS masks and the ongoing sampling of the attentional mechanism. Examining individual data, we also found a habituation effect that the participants saw significantly more stimuli as the experiment progressed. Our results suggest that these factors need to be taken care of in future CFS studies in order to achieve optimal visual awareness suppression and ensure the generalizability of results.

Look. Listen. Feel.

With its 2010 Guidelines for Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC), the American Heart Association removed its direction that first responders “look, listen, and feel for breathing.”1 Many of us in the healthcare field internalized these words during Basic Life Support (BLS) re-certification trainings. Yet, despite its persistent absence from the current official guidelines, I continue to consider this pithy phrase a tenant of assessment. It directs us be deliberate and attend to our multiple senses to increase our openness to and awareness of stimuli (internal and external)—all with the goal of facilitating and improving assessment. In this manner, the phrase is indeed “basic” (i.e., fundamental) and possesses vast utility and generalizability. Already recognized by some2 is the extension of this adage to the practice of reflection, and it is with this in mind that I invoke “look, listen, and feel” in reference to the diverse articles in this issue of Connect.

Effects of perceptual load and socially meaningful stimuli on crossmodal selective attention in Autism Spectrum Disorder and neurotypical samples.

The present study examined whether increasing visual perceptual load differentially affected both Socially Meaningful and Non-socially Meaningful auditory stimulus awareness in neurotypical (NT, n = 59) adults and Autism Spectrum Disorder (ASD, n = 57) adults. On a target trial, an unexpected critical auditory stimulus (CAS), either a Non-socially Meaningful ('beep' sound) or Socially Meaningful ('hi') stimulus, was played concurrently with the presentation of the visual task. Under conditions of low visual perceptual load both NT and ASD samples reliably noticed the CAS at similar rates (77-81%), whether the CAS was Socially Meaningful or Non-socially Meaningful. However, during high visual perceptual load NT and ASD participants reliably noticed the meaningful CAS (NT = 71%, ASD = 67%), but NT participants were unlikely to notice the Non-meaningful CAS (20%), whereas ASD participants reliably noticed it (80%), suggesting an inability to engage selective attention to ignore non-salient irrelevant distractor stimuli in ASD.

Recent cross-modal statistical learning influences visual perceptual selection.

Incoming sensory signals are often ambiguous and consistent with multiple perceptual interpretations. Information from one sensory modality can help to resolve ambiguity in another modality, but the mechanisms by which multisensory associations come to influence the contents of conscious perception are unclear. We asked whether and how novel statistical information about the coupling between sounds and images influences the early stages of awareness of visual stimuli. We exposed subjects to consistent, arbitrary pairings of sounds and images and then measured the impact of this recent passive statistical learning on subjects' initial conscious perception of a stimulus by employing binocular rivalry, a phenomenon in which incompatible images presented separately to the two eyes result in a perceptual alternation between the two images. On each trial of the rivalry test, subjects were presented with a pair of rivalrous images (one of which had been consistently paired with a specific sound during exposure while the other had not) and an accompanying sound. We found that, at the onset of binocular rivalry, an image was significantly more likely to be perceived, and was perceived for a longer duration, when it was presented with its paired sound than when presented with other sounds. Our results indicate that recently acquired multisensory information helps resolve sensory ambiguity, and they demonstrate that statistical learning is a fast, flexible mechanism that facilitates this process.

Probing Electrophysiological Indices of Perceptual Awareness across Unisensory and Multisensory Modalities.

The neural underpinnings of perceptual awareness have been extensively studied using unisensory (e.g., visual alone) stimuli. However, perception is generally multisensory, and it is unclear whether the neural architecture uncovered in these studies directly translates to the multisensory domain. Here, we use EEG to examine brain responses associated with the processing of visual, auditory, and audiovisual stimuli presented near threshold levels of detectability, with the aim of deciphering similarities and differences in the neural signals indexing the transition into perceptual awareness across vision, audition, and combined visual-auditory (multisensory) processing. More specifically, we examine (1) the presence of late evoked potentials (∼>300 msec), (2) the across-trial reproducibility, and (3) the evoked complexity associated with perceived versus nonperceived stimuli. Results reveal that, although perceived stimuli are associated with the presence of late evoked potentials across each of the examined sensory modalities, between-trial variability and EEG complexity differed for unisensory versus multisensory conditions. Whereas across-trial variability and complexity differed for perceived versus nonperceived stimuli in the visual and auditory conditions, this was not the case for the multisensory condition. Taken together, these results suggest that there are fundamental differences in the neural correlates of perceptual awareness for unisensory versus multisensory stimuli. Specifically, the work argues that the presence of late evoked potentials, as opposed to neural reproducibility or complexity, most closely tracks perceptual awareness regardless of the nature of the sensory stimulus. In addition, the current findings suggest a greater similarity between the neural correlates of perceptual awareness of unisensory (visual and auditory) stimuli when compared with multisensory stimuli.

Alcohol increases inattentional blindness when cognitive resources are not consumed by ongoing task demands

RationaleInattentional blindness (IB) is the inability to detect a salient yet unexpected task irrelevant stimulus in one’s visual field when attention is engaged in an ongoing primary task. The present study is the first to examine the impact of both task difficulty and alcohol consumption on IB and primary task performance.ObjectivesOn the basis of alcohol myopia theory, the combined effects of increased task difficulty and alcohol intoxication were predicted to impair task performance and restrict the focus of attention on to task-relevant stimuli. We therefore expected increases in breath alcohol concentration to be associated with poorer primary task performance and higher rates of IB, with these relationships being stronger under hard than easy task conditions.MethodsThis hypothesis was tested in a field study where alcohol drinkers in a local bar were randomly assigned to perform a dynamic IB task with an easy or hard visual tracking and counting task at its core (Simons and Chabris in Perception 28:1059–1074, 1999).ResultsIncreasing the difficulty of the primary task reduced task accuracy but, surprisingly, had no impact on the rate of IB. Higher levels of alcohol intoxication were, however, associated with poorer task performance and an increased rate of IB, but only under easy primary task conditions.ConclusionsResults are consistent with alcohol myopia theory. Alcohol intoxication depletes attentional resources, thus reducing the drinker’s awareness of salient stimuli that are irrelevant to some ongoing primary task. We conclude that this effect was not observed for our hard task because it is more resource intensive, so leaves no spare attentional capacity for alcohol to deplete.

Prestimulus EEG Power Predicts Conscious Awareness But Not Objective Visual Performance.

Prestimulus oscillatory neural activity has been linked to perceptual outcomes during performance of psychophysical detection and discrimination tasks. Specifically, the power and phase of low frequency oscillations have been found to predict whether an upcoming weak visual target will be detected or not. However, the mechanisms by which baseline oscillatory activity influences perception remain unclear. Recent studies suggest that the frequently reported negative relationship between α power and stimulus detection may be explained by changes in detection criterion (i.e., increased target present responses regardless of whether the target was present/absent) driven by the state of neural excitability, rather than changes in visual sensitivity (i.e., more veridical percepts). Here, we recorded EEG while human participants performed a luminance discrimination task on perithreshold stimuli in combination with single-trial ratings of perceptual awareness. Our aim was to investigate whether the power and/or phase of prestimulus oscillatory activity predict discrimination accuracy and/or perceptual awareness on a trial-by-trial basis. Prestimulus power (3–28 Hz) was inversely related to perceptual awareness ratings (i.e., higher ratings in states of low prestimulus power/high excitability) but did not predict discrimination accuracy. In contrast, prestimulus oscillatory phase did not predict awareness ratings or accuracy in any frequency band. These results provide evidence that prestimulus α power influences the level of subjective awareness of threshold visual stimuli but does not influence visual sensitivity when a decision has to be made regarding stimulus features. Hence, we find a clear dissociation between the influence of ongoing neural activity on conscious awareness and objective performance.

Specific amygdala response to masked fearful faces in post-traumatic stress relative to other anxiety disorders.

Altered amygdala activation to fear-related stimuli has been proposed to be a potential neural correlate of heightened threat sensitivity in anxiety- and stress-related disorders. However, the role of stimulus awareness and disorder specificity remains widely unclear. Here we investigated amygdala responses to conscious and unconscious fearful faces in patients suffering from panic disorder (PD), generalized anxiety disorder (GAD), or post-traumatic stress disorder (PTSD) and in a large sample of healthy controls (HC). During event-related functional magnetic resonance imaging participants (n = 120; 20 PD, 20 GAD, 20 PTSD, 60 HC) were confronted with briefly presented fearful faces, neutral faces, and non-faces in a backward masking paradigm. The design allowed for the analysis of trial-by-trial face detection performance and amygdala responses to fearful v. neutral faces. All participants exhibited increased amygdala activation to fearful v. neutral faces during conscious trials. Specifically during unconscious face processing, the PTSD, compared with all other groups, showed higher right basolateral (BLA) amygdala activity to fearful v. neutral faces. The present study shows that BLA amygdala hyperactivity during unconscious, but not conscious, processing of fearful faces differentiates PTSD from the investigated disorders. This finding suggests an automatic and specific neural hyper-responsivity to general fear cues in PTSD and supports the idea of categorical differences between PTSD and other anxiety-related disorders.