The Role of Consciousness in Coupling Emotions, Motivations, and Behaviors.

A potential function of consciousness is to integrate emotions, motivations, and subsequent behaviors into a coherent narrative [...].

The fear of spiders: perceptual features assessed in augmented reality.

Background: Persons with specific phobias typically generalize the dangerousness of the phobic animal to all members of its species, possibly as a result of malfunctioning brain circuitry normally providing quick and dirty identification of evolutionary-relevant stimuli. An objective assessment of which perceptual features make an animal more or less scary to phobic and non-phobic people would help overcome the limitations of the few studies available so far, based on self-reports. Objective: To achieve this aim, we built an augmented reality setting where volunteers with different levels of fear of spiders were asked to make holographic spiders that look either dangerous or harmless. To reach this goal, a computerized interface allowed participants to modify the spider's perceptual features (hairiness, body/leg size, and locomotion) in real time. Results: On average, the dangerous spiders were made hairy, thick, and moving according to spider-like locomotion; coherently, the harmless spiders were made hairless, slim, and moving according to a butterfly-like locomotion. However, these averaged preferences could not fully describe the complex relationship between perceptual preferences with each other and with arachnophobia symptoms. An example of a key finding revealed by cluster analysis is the similarity in perceptual preferences among participants with little or no fear of spiders, whereas participants with more arachnophobia symptoms expressed more varying preferences. Conclusion: Perceptual preferences toward the spider's features were behaviorally assessed through an observational study, objectively confirming a generalization effect characterizing spider-fearful participants. These results advance our knowledge of phobic preferences and could be used to improve the acceptability of exposure therapies.

Do Individual Differences in Perception Affect Awareness of Climate Change?

One significant obstacle to gaining a widespread awareness of the ongoing climate change is the nature of its manifestations in relation to our perception: climate change effects are gradual, distributed, and sometimes seemingly contradictory. These features result in a lag in collective climate action and sometimes foster climate skepticism and climate denial. While the literature on climate change perception and belief has thoroughly explored its sociocultural and sociopolitical aspects, research on the potential contribution of psychophysiological factors remains scarce. In this perspective paper, we outline evidence and arguments for the involvement of psychophysiological systems such as thermoception, hygroreception, and interoception in modulating climate change awareness. We discuss psychophysiological mechanisms of climate change awareness in animals and humans, as well as possible sources of individual variance in climate change perception. We conclude by suggesting novel research questions which would be worthwhile to pursue in future studies.

Unconscious multisensory integration: behavioral and neural evidence from subliminal stimuli.

Introduction: The prevailing theories of consciousness consider the integration of different sensory stimuli as a key component for this phenomenon to rise on the brain level. Despite many theories and models have been proposed for multisensory integration between supraliminal stimuli (e.g., the optimal integration model), we do not know if multisensory integration occurs also for subliminal stimuli and what psychophysical mechanisms it follows. Methods: To investigate this, subjects were exposed to visual (Virtual Reality) and/or haptic stimuli (Electro-Cutaneous Stimulation) above or below their perceptual threshold. They had to discriminate, in a two-Alternative Forced Choice Task, the intensity of unimodal and/or bimodal stimuli. They were then asked to discriminate the sensory modality while recording their EEG responses. Results: We found evidence of multisensory integration for supraliminal condition, following the classical optimal model. Importantly, even for subliminal trials participant's performances in the bimodal condition were significantly more accurate when discriminating the intensity of the stimulation. Moreover, significant differences emerged between unimodal and bimodal activity templates in parieto-temporal areas known for their integrative role. Discussion: These converging evidences - even if preliminary and needing confirmation from the collection of further data - suggest that subliminal multimodal stimuli can be integrated, thus filling a meaningful gap in the debate about the relationship between consciousness and multisensory integration.

Meta-analytic study on substance intake and work-related accidents calls for attention to bio-psycho-social factors.

Accidents at work are a major concern because of their social and economic impact. The causes are highly variable and often linked to risk behaviors that could be avoided, of which substance use is a prime example. The aim of this paper was to meta-analytically review the scientific literature on substance intake and its link to work-related accidents. From an initial pool of 19954 papers, we considered a final sample of 27 clustered in three groups according to substances class (alcohol, recreational drugs, medicines). Despite different pharmacological effects, substances consumed for recreational purposes significantly increased the risk of work-related accidents (odds ratio: alcohol 1.78, recreational drugs 1.47), whereas medicines did not: however, these results require caution due to the heterogeneity of the included studies and suspected publication bias. While bio-psycho-social factors could have helped to understand this association, selected studies neglected both the variegated effects and the root causes of recreational substance consumption. Future studies and interventions should consider these complexity factors to transcend the mere description of the phenomenon.

Functional correlates of subliminal stimulation in Posttraumatic Stress Disorder: Systematic review and meta-analysis.

Patients with Post-traumatic stress disorder (PTSD) exposed to traumatic reminders show hyperreactivity in brain areas (e.g., amygdala) belonging or related to the Innate Alarm System (IAS), allowing the rapid processing of salient stimuli. Evidence that IAS is activated by subliminal trauma-reminders could shed a new light on the factors precipitating and perpetuating PTSD symptomatology. Thus, we systematically reviewed studies investigating neuroimaging correlates of subliminal stimulation in PTSD. Twenty-three studies were selected from the MEDLINE and Scopus® databases for a qualitative synthesis, 5 of which allowed a further meta-analysis of fMRI data. The intensity of IAS responses to subliminal trauma-related reminders ranged from a minimum in healthy controls to a maximum in the PTSD patients with the most severe (e.g., dissociative) symptoms or the least responsiveness to treatment. Comparisons with other disorders (e.g., phobias) revealed contrasting results. Our findings demonstrate the hyperactivation of areas belonging or related to IAS in response to unconscious threats that should be integrated in diagnostic as well as in therapeutic protocols.

Perceptually Visible but Emotionally Subliminal Stimuli to Improve Exposure Therapies.

Subliminal stimuli are gaining growing interest due to their capability to induce desensitization to pathologically feared (e.g., phobic) pictures without inducing exaggerated emotional reactions. However, unresolved methodological issues cast significant doubt on the reliability of these findings and their interpretation. The studies most robustly assessing stimulus detection found that ~30% of the supposed-to-be-subliminal stimuli were, in fact, detected, suggesting that the beneficial effects attributed to subliminal stimuli may result from those actually seen. Nevertheless, a deeper analysis of the data underlying this misinterpretation unveils theoretical and clinical implications. Since the purpose of subliminal stimulation is to reduce the aversiveness of exposure therapies while maintaining their efficacy, researchers should measure the emotional relevance of supposed-to-be-subliminal stimuli that are, in fact, detected. A distinction is needed between perceptually- and emotionally-subliminal stimuli: the former is not consciously detected; the latter just fails to elicit emotional reactions. Emotionally-subliminal stimuli could represent an intermediate step of exposure in addition to those involving perceptually subliminal or supraliminal stimuli. Importantly, emotionally subliminal stimuli could make patients able to sustain a conscious exposure to feared stimuli without exaggeratedly reacting to them: if confirmed by empirical data, this unexpected disconfirmation of patients' beliefs could pave the way for successful therapy while increasing their self-efficacy and compliance to treatment.

Modeling subjective fear using skin conductance: a preliminary study in virtual reality.

Reliably measuring fear perception could help evaluate the effectiveness of treatments for pathological conditions such as specific phobias or post-traumatic stress syndrome (e.g., exposure therapy). In this study, we developed a novel vir-tual reality (VR) scenario to induce fear and evaluate the related physiological response by the analysis of skin conductance (SC) signal. Eighteen subjects voluntarily experienced the fear VR scenario while their SC was recorded. After the experiment, each participant was asked to score the perceived subjective fear using a Likert scale from 1 to 10. We used the cvxEDA algorithm to process the collected SC signals and extract several features able to estimate the autonomic response to the fearful stimuli. Finally, the extracted features were linearly combined to model the subjective fear perception scores by means of LASSO linear regression. The sparsification imposed by the LASSO procedure to mitigate the overfitting risk identified an optimal linear model including only the standard deviation of the tonic SC component as a regressor (p = 0.007; R2 = 0.3337). The significant contribution of this feature to the model suggests that subjects experiencing more intense subjective fear have a more variable and unstable sympathetic tone.

Lavender aromatherapy: A systematic review from essential oil quality and administration methods to cognitive enhancing effects.

Modern society is reviving the practice of aromatherapy, and lavender is reported being the most worldwide purchased plant for essential oil (EO) extraction. Since recent studies reported cognitive enhancing effects of lavender besides the hypno-inducing effects, a literature review is needed. Considering EO quality and diffusion devices, we conducted a systematic review on the effects of lavender EO inhalation on arousal, attention and memory in healthy subjects. Starting from this new multidisciplinary perspective, cognitive effects were reviewed to link outcomes to effective and reproducible protocols. A systematic search on MEDLINE, ERIC, PsycInfo, Google Scholar, and Scopus databases using Cognitive Atlas and plant-related keywords was conducted. Among the 1,203 articles yielded, 11 met eligibility criteria. Subjects administered with lavender EO displayed arousal decrease and sustained attention increase. Controversial results emerged regarding memory. Lack of EO quality assessment and protocols heterogeneity did not allow assessing whether different EO composition differentially modulates cognition and whether placebo effect can be discerned from EO effect itself. However, GABAergic pathway modulation exerted by linalool, a major lavender EO constituent, might explain cognitive functions empowerment. We speculate aromatherapy could be a burgeoning cognition enhancing tool, although further investigation is required to reach robust conclusions.

A Systematic Review on the Role of Substance Consumption in Work-Related Road Traffic Crashes Reveals the Importance of Biopsychosocial Factors in Prevention.

OBJECTIVE: Since many jobs imply driving, a relevant part of all road traffic crashes (RTC) is related to work. Statistics considering all crashes suggest that they are significantly associated with consumption of substances, but the root causes are not yet clear. The objective of the present paper was to systematically review the scientific literature concerning substances consumption and work-related RTC. We queried the PubMed and Scopus electronic databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles were included if they reported all necessary data and survived a quality assessment. We selected a final sample of 30 articles from an initial pool of 7113. As hypothesized, taking any of the considered substances was found to increase the risk of work-related RTC. Descriptive statistics on work-related RTC showed a higher average positivity rate for medicines (14.8%) than for alcohol (3.02%) and drugs (0.84%). Interestingly, the impact of some medications found an unconvincing explanation in the mere occurrence of side effects, and it suggests that psychosocial and/or medical conditions could be better predictors of RTC. We therefore propose an intervention and prevention model that also considers biopsychosocial factors, for which further studies are needed in future research.

Systematic Review of Studies on Subliminal Exposure to Phobic Stimuli: Integrating Therapeutic Models for Specific Phobias.

We systematically review 26 papers investigating subjective, behavioral, and psychophysiological correlates of subliminal exposure to phobic stimuli in phobic patients. Stimulations were found to elicit: (1) cardiac defense responses, (2) specific brain activations of both subcortical (e.g., amygdala) and cortical structures, (3) skin conductance reactions, only when stimuli lasted >20 ms and were administered with intertrial interval >20 s. While not inducing the distress caused by current (supraliminal) exposure therapies, exposure to subliminal phobic stimuli still results in successful extinction of both psychophysiological and behavioral correlates: however, it hardly improves subjective fear. We integrate those results with recent bifactorial models of emotional regulation, proposing a new form of exposure therapy whose effectiveness and acceptability should be maximized by a preliminary subliminal stimulation. Systematic Review Registration: identifier [CRD42021129234].

Unconscious processing of subliminal stimuli in panic disorder: A systematic review and meta-analysis.

Attentional biases to threat exist in panic disorder (PD), probably related to altered subliminal processing. We systematically reviewed studies investigating subliminal processing in PD. Studies were retrieved from MEDLINE and Scopus®. We meta-analytically compared PD (n = 167) and healthy controls (HC, n = 165) for processing of masked panic-related and neutral words. We also compared subliminal and supraliminal presentations of panic-related words relative to neutral words within PD subjects and HC. We found a significantly enhanced Stroop interference to masked panic-related words in PD vs HC (Hedges' g = 0.60, p = 0.03; Q = 14.83, I2 = 66.3 %, p = 0.01). While both PD subjects and HC tended to be slower to respond to supraliminal threat words than to neutral words, PD subjects only showed a marginally significant slower response to subliminal panic-related words vs neutral words. Findings remain inconclusive regarding comparison to other mental disorders, neural correlates, and the effect of psychotherapy. Even if possibly flawed by methodological weaknesses, our findings support the existence of a sensitivity to subliminal threat cues in PD, which could be targeted to improve treatment.

Interior Color and Psychological Functioning in a University Residence Hall.

The research exploited a unique architectural setting of a university residence hall composed by six separate buildings that matched for every architectural detail and differed only for the interior color (violet, blue, green, yellow, orange, and red). Four hundred and forty-three students living in the six buildings for an average of 13.33 months participated in a study that assessed color preference (hue and lightness), lightness preference, and the effects of color on studying and mood. The results showed a preference for blue interiors, followed by green, violet, orange, yellow, and red. A preference bias was found for the specific color in which the student lived. Gender differences emerged for the preference of blue and violet. Room-lightness was significantly affected by the interior color. Room ceiling was preferred white. Blue as interior color was considered to facilitate studying activity. The use of differentiated colors in the six buildings was evaluated to significantly facilitate orienting and wayfinding. A significant relation was found between a calm mood and preference for blue.