Olfactory sniffing signals consciousness in unresponsive patients with brain injuries.

After severe brain injury, it can be difficult to determine the state of consciousness of a patient, to determine whether the patient is unresponsive or perhaps minimally conscious1, and to predict whether they will recover. These diagnoses and prognoses are crucial, as they determine therapeutic strategies such as pain management, and can underlie end-of-life decisions2,3. Nevertheless, there is an error rate of up to 40% in determining the state of consciousness in patients with brain injuries4,5. Olfaction relies on brain structures that are involved in the basic mechanisms of arousal6, and we therefore hypothesized that it may serve as a biomarker for consciousness7. Here we use a non-verbal non-task-dependent measure known as the sniff response8-11 to determine consciousness in patients with brain injuries. By measuring odorant-dependent sniffing, we gain a sensitive measure of olfactory function10-15. We measured the sniff response repeatedly over time in patients with severe brain injuries and found that sniff responses significantly discriminated between unresponsive and minimally conscious states at the group level. Notably, at the single-patient level, if an unresponsive patient had a sniff response, this assured future regaining of consciousness. In addition, olfactory sniff responses were associated with long-term survival rates. These results highlight the importance of olfaction in human brain function, and provide an accessible tool that signals consciousness and recovery in patients with brain injuries.

Mindfulness training preserves sustained attention and resting state anticorrelation between default-mode network and dorsolateral prefrontal cortex: A randomized controlled trial.

Mindfulness training can enhance cognitive control, but the neural mechanisms underlying such enhancement in children are unknown. Here, we conducted a randomized controlled trial (RCT) with sixth graders (mean age 11.76 years) to examine the impact of 8 weeks of school-based mindfulness training, relative to coding training as an active control, on sustained attention and associated resting-state functional brain connectivity. At baseline, better performance on a sustained-attention task correlated with greater anticorrelation between the default mode network (DMN) and right dorsolateral prefrontal cortex (DLPFC), a key node of the central executive network. Following the interventions, children in the mindfulness group preserved their sustained-attention performance (i.e., fewer lapses of attention) and preserved DMN-DLPFC anticorrelation compared to children in the active control group, who exhibited declines in both sustained attention and DMN-DLPFC anticorrelation. Further, change in sustained-attention performance correlated with change in DMN-DLPFC anticorrelation only within the mindfulness group. These findings provide the first causal link between mindfulness training and both sustained attention and associated neural plasticity. Administered as a part of sixth graders' school schedule, this RCT supports the beneficial effects of school-based mindfulness training on cognitive control.

Poor lie detection related to an under-reliance on statistical cues and overreliance on own behaviour.

The surge of online scams is taking a considerable financial and emotional toll. This is partially because humans are poor at detecting lies. In a series of three online experiments (Nexp1 = 102, Nexp2 = 108, Nexp3 = 100) where participants are given the opportunity to lie as well as to assess the potential lies of others, we show that poor lie detection is related to the suboptimal computations people engage in when assessing lies. Participants used their own lying behaviour to predict whether other people lied, despite this cue being uninformative, while under-using more predictive statistical cues. This was observed by comparing the weights participants assigned to different cues, to those of a model trained on the ground truth. Moreover, across individuals, reliance on statistical cues was associated with better discernment, while reliance on one's own behaviour was not. These findings suggest scam detection may be improved by using tools that augment relevant statistical cues.

Does disconfirmatory evidence shape safety-and danger-related beliefs of trauma-exposed individuals?

Recent accounts of predictive processing in posttraumatic stress disorder (PTSD) suggest that trauma-exposed individuals struggle to update trauma-related hypotheses predicting danger, which may be involved in the etiology and maintenance of this disorder. Initial research supports this account, documenting an association between trauma-exposure, impaired expectation updating, and PTSD symptoms. Yet, no study to date has examined biased belief updating in PTSD using a scenario-based approach.Objective: Here, we examined the predictive processing account among trauma-exposed and non-trauma-exposed individuals using a modified Trauma-Related version of the Bias Against Disconfirmatory Evidence task.Method: The task presents both danger-and safety-related scenarios highly relevant for trauma-exposed individuals. For each scenario, participants viewed several explanations and rated their plausibility. Their ability to update their initial interpretation following new-contradictory information was assessed.Results: Preregistered analyses did not reveal any significant findings. Based on indications that our sample may not have been sufficiently powered, we conducted exploratory analyses in an extended sample of participants. These analyses yielded a significant association between reduced belief updating and PTSD symptoms which was evident for disconfirming both safety and danger scenarios. However, the effect sizes we found were in the small-to-medium range.Conclusion: Although preliminary, our current findings support initial evidence that individuals with higher PTSD symptoms show a higher resistance to update their beliefs upon new disconfirmatory evidence. Our results should be interpreted cautiously in light of the extended sample and the limitations of the current study.

We developed a modified version of the Bias Against Disconfirmatory Evidence task.We found significant associations between PTSD symptoms and belief updating.The association was evident for disconfirming both safety and danger scenarios.

Association of pessimism with cardiovascular events and all-cause mortality.

Poor psychological health is associated with Takotsubo cardiomyopathy, cardiac syndrome X, coronary microcirculatory dysfunction, peripheral artery disease, or spontaneous coronary artery dissection. Data regarding pessimism, cardiovascular disease (CVD) events and mortality and all-cause mortality remained inconclusive. This systematic review and meta-analysis aim to provide an overview of the association between pessimism, CVD outcomes and mortality. A systematic search of electronic databases was conducted from inception through July 2022 for studies evaluating pessimism and adverse outcomes. A total of 17 studies published between 1966 and July 2022 met our inclusion criteria, for a total of 232,533 individuals. Pooled hazard ratios were calculated in random-effects meta-analyses. Based on pooled analysis of adjusted HRs, pessimism was associated with adjusted HR of 1.13 (95% CI 1.07-1.19) for all-cause mortality with minimal heterogeneity (I2 = 28.5%). Based on pooled analysis of adjusted HRs, pessimism was associated with adjusted HR of 1.30 (95% CI 0.43-3.95) for CHD mortality, adjusted HR of 1.41 (95% CI 1.05-1.91) for CVD mortality, and adjusted HR of 1.43 (95% CI 0.64-3.16) for stroke. In conclusion, pessimism seems to be significantly associated with a higher risk for and poorer outcomes from CVD events than optimistic styles. There are genetic and other bases for these life approaches, but behavioral, cognitive and meditative interventions can modify patients' level of pessimism, hopefully leading to better medical outcomes. Testing this theory would yield highly useful and practical data for clinical care.

How beliefs about coronavirus disease (COVID) influence COVID-like symptoms? - A longitudinal study.

OBJECTIVE: Evidence from psychosomatic and nocebo research has indicated that believing one will develop symptoms makes the experience of such symptoms more likely. We applied this idea in the context of coronavirus disease 2019 (COVID-19). Specifically, we assessed whether beliefs regarding COVID-19 predict COVID-like symptoms 3-4 weeks later, and what specific belief has the greatest influence on symptom experience. METHOD: We conducted two studies with over 300 participants, approached at two successive timepoints, 3-4 weeks apart. Participants reported their experienced symptoms, COVID-19-related beliefs, demographics, and state anxiety. To target COVID-like symptoms, participants who reported having contracted COVID-19 or attributed their symptoms to another known cause were excluded. Regression analyses were conducted to test the predictive value of beliefs regarding COVID-19 on experienced symptoms. RESULTS: A particular belief regarding one's estimated symptom severity if infected with coronavirus predicted the experience of symptoms 3-4 weeks later (ß = .17, p = .011). This result persisted after controlling for potential confounds, including state anxiety (ß = .22, p = .002). Findings were preregistered and replicated in a separate cohort. A novel scale for perception of the body's ability to fight diseases contributed to mediating the effect of estimated symptom severity on later experienced symptoms. CONCLUSIONS: A particular belief about estimated symptom severity if infected with COVID predicted the experience of COVID-like physical symptoms several weeks later. These findings contribute to the understanding of the development of unexplained physical symptoms. Furthermore, identification of a particular belief that increases the likelihood of symptoms informs intervention that may mitigate its effects. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Acceptance and commitment therapy for episodic migraine: Rationale and design of a pilot randomized controlled trial.

Migraine is a debilitating disorder with limited pharmacological options. Many migraine medications can have intolerable side effects leading patients to seek complementary and integrative health (CIM) approaches for treatment. One option that is growing in popularity and evidence is Acceptance and Commitment Therapy (ACT), a mindfulness-based therapy. The purpose of this paper is to describe how ACT may be an effective modality integrated into the treatment of migraine and to describe the design of a pilot study of ACT for migraine. First, we review the research and the promise of mindfulness therapies for the treatment of migraine. Then, we describe how ACT differs from other mindfulness therapies for migraine and why it can be a promising option for these patients. Finally, we summarize the design of a pilot study designed to determine the feasibility of performing a future fully powered study to determine the effectiveness of ACT on migraine frequency and disability. This pilot study includes unique features, including a remotely-delivered ACT intervention and the measurement of cortisol levels before and after the intervention.

When Beliefs Face Reality: An Integrative Review of Belief Updating in Mental Health and Illness.

Belief updating is a relatively nascent field of research that examines how people adjust their beliefs in light of new evidence. So far, belief updating has been investigated in partly unrelated lines of research from different psychological disciplines. In this article, we aim to integrate these disparate lines of research. After presenting some prominent theoretical frameworks and experimental designs that have been used for the study of belief updating, we review how healthy people and people with mental disorders update their beliefs after receiving new information that supports or challenges their views. Available evidence suggests that both healthy people and people with particular mental disorders are prone to certain biases when updating their beliefs, although the nature of the respective biases varies considerably and depends on several factors. Anomalies in belief updating are discussed in terms of both new insights into the psychopathology of various mental disorders and societal implications, such as irreconcilable political and societal controversies due to the failure to take information into account that disconfirms one's own view. We conclude by proposing a novel integrative model of belief updating and derive directions for future research.

Enhanced rationality in autism spectrum disorder.

Challenges in social cognition and communication are core characteristics of autism spectrum disorder (ASD), but in some domains, individuals with ASD may display typical abilities and even outperform their neurotypical counterparts. These enhanced abilities are notable in the domains of reasoning, judgment and decision-making, in which individuals with ASD often show 'enhanced rationality' by exhibiting more rational and bias-free decision-making than do neurotypical individuals. We review evidence for enhanced rationality in ASD, how it relates to theoretical frameworks of information processing in ASD, its implications for basic research about human irrationality, and what it may mean for the ASD community.

Sniffing the human body volatile hexadecanal blocks aggression in men but triggers aggression in women.

In terrestrial mammals, body volatiles can effectively trigger or block conspecific aggression. Here, we tested whether hexadecanal (HEX), a human body volatile implicated as a mammalian-wide social chemosignal, affects human aggression. Using validated behavioral paradigms, we observed a marked dissociation: Sniffing HEX blocked aggression in men but triggered aggression in women. Next, using functional brain imaging, we uncovered a pattern of brain activity mirroring behavior: In both men and women, HEX increased activity in the left angular gyrus, an area implicated in perception of social cues. HEX then modulated functional connectivity between the angular gyrus and a brain network implicated in social appraisal (temporal pole) and aggressive execution (amygdala and orbitofrontal cortex) in a sex-dependent manner consistent with behavior: increasing connectivity in men but decreasing connectivity in women. These findings implicate sex-specific social chemosignaling at the mechanistic heart of human aggressive behavior.

Understanding persistent physical symptoms: Conceptual integration of psychological expectation models and predictive processing accounts.

Persistent physical symptoms (PPS) are distressing, difficult to treat, and pose a major challenge to health care providers and systems. In this article, we review two disparate bodies of literature on PPS to provide a novel integrative model of this elusive condition. First, we draw on the clinical-psychological literature on the role of expectations to suggest that people with PPS develop dysfunctional expectations about health and disease that become increasingly immune to disconfirmatory information (such as medical reassurance) through cognitive reappraisal. Second, we invoke neuroscientific predictive processing accounts and propose that the psychological process of 'cognitive immunization' against disconfirmatory evidence corresponds, at the neurobiological and computational level, to too much confidence (i.e. precision) afforded to prior predictions. This can lead to an attenuation of disconfirming sensory information so that strong priors override benign bodily signals and make people believe that something serious is wrong with the body. Combining these distinct accounts provides a unifying framework for persistent physical symptoms and shifts the focus away from their causes to the sustaining mechanisms that prevent symptoms from subsiding spontaneously. Based on this integrative model, we derive new avenues for future research and discuss implications for treating people with PPS in clinical practice.

Distorted Cognitive Processes in Major Depression: A Predictive Processing Perspective.

The cognitive model of depression has significantly influenced the understanding of distorted cognitive processes in major depression; however, this model's conception of cognition has recently been criticized as possibly too broad and unspecific. In this review, we connect insights from cognitive neuroscience and psychiatry to suggest that the traditional cognitive model may benefit from a reformulation that takes current Bayesian models of the brain into account. Appealing to a predictive processing account, we explain that healthy human learning is normally based on making predictions and experiencing discrepancies between predicted and actual events or experiences. We present evidence suggesting that this learning mechanism is distorted in depression: current research indicates that people with depression tend to negatively reappraise or disregard positive information that disconfirms negative expectations, thus resulting in sustained negative predictions and biased learning. We also review the neurophysiological correlates of such deficits in processing prediction errors in people with depression. Synthesizing these findings, we propose a novel mechanistic model of depression suggesting that people with depression have the tendency to predominantly expect negative events or experiences, which they subjectively feel confirmed due to reappraisal of disconfirming evidence, thus creating a self-reinforcing negative feedback loop. Computationally, we consider too much precision afforded to negative prior beliefs as the main candidate of pathology, accompanied by an attenuation of positive prediction errors. We conclude by outlining some directions for future research into the understanding of the behavioral and neurophysiological underpinnings of this model and point to clinical implications of it.

Unexplained repeated pregnancy loss is associated with altered perceptual and brain responses to men's body-odor.

Mammalian olfaction and reproduction are tightly linked, a link less explored in humans. Here, we asked whether human unexplained repeated pregnancy loss (uRPL) is associated with altered olfaction, and particularly altered olfactory responses to body-odor. We found that whereas most women with uRPL could identify the body-odor of their spouse, most control women could not. Moreover, women with uRPL rated the perceptual attributes of men's body-odor differently from controls. These pronounced differences were accompanied by an only modest albeit significant advantage in ordinary, non-body-odor-related olfaction in uRPL. Next, using structural and functional brain imaging, we found that in comparison to controls, most women with uRPL had smaller olfactory bulbs, yet increased hypothalamic response in association with men's body-odor. These findings combine to suggest altered olfactory perceptual and brain responses in women experiencing uRPL, particularly in relation to men's body-odor. Whether this link has any causal aspects to it remains to be explored.

Altered responses to social chemosignals in autism spectrum disorder.

Autism spectrum disorder (ASD) is characterized by impaired social communication, often attributed to misreading of emotional cues. Why individuals with ASD misread emotions remains unclear. Given that terrestrial mammals rely on their sense of smell to read conspecific emotions, we hypothesized that misreading of emotional cues in ASD partially reflects altered social chemosignaling. We found no difference between typically developed (TD) and cognitively able adults with ASD at explicit detection and perception of social chemosignals. Nevertheless, TD and ASD participants dissociated in their responses to subliminal presentation of these same compounds: the undetected 'smell of fear' (skydiver sweat) increased physiological arousal and reduced explicit and implicit measures of trust in TD but acted opposite in ASD participants. Moreover, two different undetected synthetic putative social chemosignals increased or decreased arousal in TD but acted opposite in ASD participants. These results implicate social chemosignaling as a sensory substrate of social impairment in ASD.

Creative foraging: An experimental paradigm for studying exploration and discovery.

Creative exploration is central to science, art and cognitive development. However, research on creative exploration is limited by a lack of high-resolution automated paradigms. To address this, we present such an automated paradigm, the creative foraging game, in which people search for novel and valuable solutions in a large and well-defined space made of all possible shapes made of ten connected squares. Players discovered shape categories such as digits, letters, and airplanes as well as more abstract categories. They exploited each category, then dropped it to explore once again, and so on. Aligned with a prediction of optimal foraging theory (OFT), during exploration phases, people moved along meandering paths that are about three times longer than the shortest paths between shapes; when exploiting a category of related shapes, they moved along the shortest paths. The moment of discovery of a new category was usually done at a non-prototypical and ambiguous shape, which can serve as an experimental proxy for creative leaps. People showed individual differences in their search patterns, along a continuum between two strategies: a mercurial quick-to-discover/quick-to-drop strategy and a thorough slow-to-discover/slow-to-drop strategy. Contrary to optimal foraging theory, players leave exploitation to explore again far before categories are depleted. This paradigm opens the way for automated high-resolution study of creative exploration.

Placebo can enhance creativity.

BACKGROUND: The placebo effect is usually studied in clinical settings for decreasing negative symptoms such as pain, depression and anxiety. There is interest in exploring the placebo effect also outside the clinic, for enhancing positive aspects of performance or cognition. Several studies indicate that placebo can enhance cognitive abilities including memory, implicit learning and general knowledge. Here, we ask whether placebo can enhance creativity, an important aspect of human cognition. METHODS: Subjects were randomly assigned to a control group who smelled and rated an odorant (n = 45), and a placebo group who were treated identically but were also told that the odorant increases creativity and reduces inhibitions (n = 45). Subjects completed a recently developed automated test for creativity, the creative foraging game (CFG), and a randomly chosen subset (n = 57) also completed two manual standardized creativity tests, the alternate uses test (AUT) and the Torrance test (TTCT). In all three tests, participants were asked to create as many original solutions and were scored for originality, flexibility and fluency. RESULTS: The placebo group showed higher originality than the control group both in the CFG (p<0.04, effect size = 0.5) and in the AUT (p<0.05, effect size = 0.4), but not in the Torrance test. The placebo group also found more shapes outside of the standard categories found by a set of 100 CFG players in a previous study, a feature termed out-of-the-boxness (p<0.01, effect size = 0.6). CONCLUSIONS: The findings indicate that placebo can enhance the originality aspect of creativity. This strengthens the view that placebo can be used not only to reduce negative clinical symptoms, but also to enhance positive aspects of cognition. Furthermore, we find that the impact of placebo on creativity can be tested by CFG, which can quantify multiple aspects of creative search without need for manual coding. This approach opens the way to explore the behavioral and neural mechanisms by which placebo might amplify creativity.

SEPT14 Is Associated with a Reduced Risk for Parkinson's Disease and Expressed in Human Brain.

Genes involved in cytoskeletal stability and trafficking, such as MAPT and SNCA, are important risk factors for Parkinson's disease (PD). Two members of the cytoskeletal Septin family, SEPT4 and SEPT5, were implicated in PD pathobiology. We aimed to determine whether Septin genes are associated with Parkinson's disease. To this end, six SNPs located in four different Septin loci were analyzed in 720 PD patients and 740 controls, all of Ashkenazi-Jewish origin. In addition, SEPT14 was sequenced and its expression was determined in different human tissues. Our results revealed that two SNPs in the SEPT14 locus, rs11981883 and rs10241628, were associated with a reduced risk for PD (p = 0.02 and p = 0.005). A third SNP, rs77231105, was localized in the putative promoter of SEPT14 and was predicted to affect the binding of the transcription factor Nkx2.5. This SNP was also associated with a reduced risk for PD (OR = 0.28, p < 0.0007). The three SEPT14 SNPs defined a protective haplotype which significantly reduced the risk for PD by 4-fold (p = 0.002). SEPT14 was found to be expressed in the brain and in the Substantia Nigra. These results suggest that SEPT14 may have a protective role in Parkinson's disease pathogenesis, yet more studies are necessary to validate these results.