Does a single session of transcranial direct current stimulation enhance both physical and psychological performance in national- or international-level athletes? A systematic review.

Some studies showed that a single session of transcranial direct current stimulation (tDCS) has the potential of modulating motor performance in healthy and athletes. To our knowledge, previously published systematic reviews have neither comprehensively investigated the effects of tDCS on athletic performance in both physical and psychological parameters nor investigated the effects of tDCS on high-level athletes. We examined all available research testing a single session of tDCS on strength, endurance, sport-specific performance, emotional states and cognitive performance for better application in competition and pre-competition trainings of national- or international-level athletes. A systematic search was conducted in PubMed, Web of Science, EBSCO, Embase, and Scopus up until to June 2023. Studies were eligible when participants had sports experience at a minimum of state and national level competitions, underwent a single session of tDCS without additional interventions, and received either sham tDCS or no interventions in the control groups. A total of 20 experimental studies (224 participants) were included from 18 articles. The results showed that a single tDCS session improved both physical and psychological parameters in 12 out of the 18 studies. Of these, six refer to the application of tDCS on the motor system (motor cortex, premotor cortex, cerebellum), five on dorsolateral prefrontal cortex and two on temporal cortex. The most sensitive to tDCS are strength, endurance, and emotional states, improved in 67%, 75%, and 75% of studies, respectively. Less than half of the studies showed improvement in sport-specific tasks (40%) and cognitive performance (33%). We suggest that tDCS is an effective tool that can be applied to competition and pre-competition training to improve athletic performance in national- or international-level athletes. Further research would explore various parameters (type of sports, brain regions, stimulation protocol, athlete level, and test tasks) and neural mechanistic studies in improving efficacy of tDCS interventions. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326989, identifier CRD42022326989.

From real to virtual prism adaptation therapy: a systematic review on benefits and challenges of a new potential rehabilitation approach.

Prism adaptation (PA) is a sensorimotor technique that has been shown to alleviate neglect symptoms. Due to its demonstrated functional effectiveness, PA has recently been implemented in virtual reality environments. However, research on virtual prism adaptation (VPA) is limited and it lacks a standardized methodological approach. It is crucial to investigate whether VPA can be effective in inducing traditional effect of PA and to have potential utility in a rehabilitation context. Clarifying this aspect would allow the use of VPA in a wider range of contexts and neurological disorders, with the additional opportunity to overcome PA traditional limits. The aim of the present study is to revise current literature on VPA in both healthy individuals and patients highlighting also its advantages and limitations. Studies performed between 2013 and 2023 and fulfilling the inclusion criteria were searched on three electronic databases, by combining the terms "Virtual prism adaptation" and "Virtual prism adaptation therapy. Out of 123 articles, only 16 met the inclusion criteria. The current literature review suggests that VPA may serve as a potentially useful tool for inducing visuomotor adaptation, with most studies conducted in healthy individuals. The high variability in the methodologies observed among studies suggests that more standardized approaches are needed to gain a deeper understanding of the mechanisms underlying adaptation and aftereffects when PA is administered in a virtual environment. Future studies should also address practical applications and clinical efficacy of VPA, particularly in patients with spatial neglect.

Virtual Reality Exposure Therapy for Treating Fear of Contamination Disorders: A Systematic Review of Healthy and Clinical Populations.

Virtual Reality Exposure Therapy (VRET), particularly immersive Virtual Reality Exposure Therapy (iVRET), has gained attraction as an innovative approach in exposure therapy (ET), notably for some anxiety disorders with a fear of contamination component, such as spider phobia (SP) and obsessive-compulsive disorder (OCD). This systematic work investigates iVRET's effectiveness in modulating disgust emotion-a shared aberrant feature across these disorders. Recent reviews have evaluated VRET's efficacy against in vivo ET. However, emerging evidence also highlights iVRET's potential in diminishing atypical disgust and related avoidance behaviors, expanding beyond traditional fear-focused outcomes. Our systematic synthesis, adhering to PRISMA guidelines, aims to fill this gap by assessing iVRET's efficacy in regulating disgust emotion within both clinical and at-risk populations, identified through standardized questionnaires and subjective disgust ratings. This research analyzes data from eight studies on clinical populations and five on healthy populations, offering an insight into iVRET's potential to mitigate the aberrant disgust response, a common transdiagnostic feature in varied psychopathologies. The findings support iVRET's clinical relevance in disgust management, providing evidence for a broader therapeutic application of iVRET and pointing out the need for more focused and complete investigations in this emergent field.

Targeting the prefrontal-supplementary motor network in obsessive-compulsive disorder with intensified electrical stimulation in two dosages: a randomized, controlled trial.

Obsessive-compulsive disorder (OCD) is associated with a high disease burden, and treatment options are limited. We used intensified electrical stimulation in two dosages to target a main circuitry associated with the pathophysiology of OCD, left dorsolateral prefrontal cortex (l-DLPFC), and pre-supplementary motor area (pre-SMA) and assessed clinical outcomes, neuropsychological performance, and brain physiology. In a double-blind, randomized controlled trial, thirty-nine patients with OCD were randomly assigned to three groups of sham, 2-mA, or 1-mA transcranial direct current stimulation (tDCS) targeting the l-DLPFC (F3) and pre-SMA (FC2) with anodal and cathodal stimulation respectively. The treatment included 10 sessions of 20-minute stimulation delivered twice per day with 20-min between-session intervals. Outcome measures were reduction in OCD symptoms, anxiety, and depressive states, performance on a neuropsychological test battery (response inhibition, working memory, attention), oscillatory brain activities, and functional connectivity. All outcome measures except EEG were examined at pre-intervention, post-intervention, and 1-month follow-up times. The 2-mA protocol significantly reduced OCD symptoms, anxiety, and depression states and improved quality of life after the intervention up to 1-month follow-up compared to the sham group, while the 1-mA protocol reduced OCD symptoms only in the follow-up and depressive state immediately after and 1-month following the intervention. Both protocols partially improved response inhibition, and the 2-mA protocol reduced attention bias to OCD-related stimuli and improved reaction time in working memory performance. Both protocols increased alpha oscillatory power, and the 2-mA protocol decreased delta power as well. Both protocols increased connectivity in higher frequency bands at frontal-central areas compared to the sham. Modulation of the prefrontal-supplementary motor network with intensified tDCS ameliorates OCD clinical symptoms and results in beneficial cognitive effects. The 2-mA intensified stimulation resulted in larger symptom reduction and improved more converging outcome variables related to therapeutic efficacy. These results support applying the intensified prefrontal-SMA tDCS in larger trials.

Evolution of Severe Closed Head Injury: Assessing Ventricular Volume and Behavioral Measures at 30 and 90 Days Post-Injury.

Background: Assessing functional outcomes in Severe Closed Head Injury (SCHI) is complex due to brain parenchymal changes. This study examines the Ventricles to Intracranial Volume Ratio (VBR) as a metric for these changes and its correlation with behavioral scales. Methods: Thirty-one SCHI patients were included. VBR was derived from CT scans at 3, 30, and 90 days post-injury and compared with Levels of Cognitive Functioning (LCF), Disability Rating Scale (DRS), and Early Rehabilitation Barthel Index (ERBI) assessments at 30 and 90 days. Results: Ten patients were excluded post-decompressive craniectomy or ventriculoperitoneal shunt. Findings indicated a VBR decrease at 3 days, suggesting acute phase compression, followed by an increase from 30 to 90 days, indicative of post-acute brain atrophy. VBR correlated positively with the Marshall score in the initial 72 h, positioning it as an early indicator of subsequent brain atrophy. Nevertheless, in contrast to the Marshall score, VBR had stronger associations with DRS and ERBI at 90 days. Conclusions: VBR, alongside behavioral assessments, presents a robust framework for evaluating SCHI progression. It supports early functional outcome correlations informing therapeutic approaches. VBR's reliability underscores its utility in neurorehabilitation for ongoing SCHI assessment and aiding clinical decisions.

Individual predictors of vaccine hesitancy in the Italian post COVID-19 pandemic era.

A wide range of survey studies have explored vaccination hesitancy/resistance during the COVID-19 pandemic and provided evidence that this can be explained by several individual variables from the ideological, clinical, and socio-affective domain. However, evidence about which individual variables predict vaccine hesitancy in the post-pandemic state of COVID-19 is meager. We administered a battery of questionnaires to a group of 120 Italian participants with high and low scores on the adult vaccine hesitancy scale (aVHS) to investigate the predictive role of ideological (i.e. political orientation), clinical (i.e. anxiety, interoceptive accuracy), and socio-affective (i.e. alexithymia, disgust sensitivity/propensity, empathy) variables on vaccine hesitancy/resistance. This study provides evidence that lower interoceptive awareness and cognitive empathy are predictors of a greater hesitancy to get vaccinated in the post-pandemic COVID-19 state.

Interoceptive and Affective Alterations in Body Integrity Dysphoria: An Online Self-Reporting Study.

INTRODUCTION: Body integrity dysphoria (BID) is a rare condition in which individuals experience a long-lasting desire to achieve a specific physical disability. In this study, we tested the hypothesis of interoceptive and affective abnormalities in BID, in line with the evidence of structural and functional alteration of the interoceptive-affective neural system in these individuals. METHOD: Our study involved 68 participants with BID (mean age: 35.6, SD: 16.4). Among these participants, 47 expressed a desire for amputation, 14 desired paralysis, 3 sought sensory deprivation, and 3 desired a combination of these forms. For comparisons, we recruited a control group of 79 participants (mean age: 35.2, SD: 15.8). We administered assessment measures to investigate alexithymia level (TAS-20), disgust sensitivity (DS-R), interoceptive awareness (MAIA-2), and (affective and cognitive) empathy (QCAE). We also administered the Short Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) to identify psychiatric comorbidities. Subgroups with low O-LIFE scores (BID = 31; controls = 43) and subgroups with high O-LIFE scores (BID = 37; controls = 36) were derived through a median-split procedure. RESULTS: Within the BID low O-LIFE group, we found reduced interoceptive sensibility, reduced disgust sensitivity, and increased difficulty in identifying feelings, which refers to a dimension of the alexithymia trait. Within the BID high O-LIFE group, we observed a reduced disgust sensitivity and interoceptive sensibility, accompanied by a diminished score in cognitive empathy. CONCLUSION: Our study suggests that BID can be associated with altered interoceptive and affective processing.

Evidence for a dissociation between moral reasoning and moral decision-making in Tourette syndrome.

Despite the growing interest on how Tourette syndrome (TS) affects social cognition skills, this field remains to date relatively under-explored. Here, we aim to advance knowledge on the topic by studying moral decision-making and moral reasoning in a group of adolescents with TS and a group of healthy controls. Overall, we found higher endorsement (i.e. a greater 'yes' response rate) for utilitarian solutions of incidental and instrumental moral dilemmas in TS compared to controls. By contrast, we reported an overall higher tendency of TS individuals to apply principles described in the moral foundation questionnaire to establish whether something is morally right or wrong. Our results document intact moral reasoning in TS and suggest that a deficit in suppressing inappropriate behaviours and/or altered sense of agency might be responsible for their higher utilitarian moral decision-making.

Evidence of Altered Fear Extinction Learning in Individuals with High Vaccine Hesitancy During Covid-19 Pandemic.

Objective: A relevance of fear and concerns about vaccine development and its side effects are suggested to explain COVID-19 vaccine hesitancy. However, evidence supporting the phobic origin hypothesis of hesitancy for COVID-19 and other vaccinations remains indirect and elusive. Method: We addressed this issue by investigating the existence of a relationship between fear conditioning, extinction, and the respective vaccination hesitancy and anxiety scores in a group of 25 individuals. Results: Overall, we show that the general mechanism of fear extinction learning is impaired in individuals with high vaccine hesitancy. State and trait anxiety scores do not account for this result. Conclusions: These findings suggest that attitudes against vaccination could be linked to an altered inhibitory learning process.

Disgust as a transdiagnostic index of mental illness: A narrative review of clinical populations.

Disgust is a basic emotion of rejection, providing an ancestral defensive mechanism against illness. Based on research that documents altered experiences of disgust across several psychopathological conditions, we conducted a narrative review to address the hypothesis that altered disgust may serve as a transdiagnostic index of mental illness. Our synthesis of the literature from past decades suggests that, compared to healthy populations, patients with mental disorders exhibit abnormal processing of disgust in at least one of the analyzed dimensions. We also outline evidence of alterations in brain areas relevant to disgust processing, such as the insula and the interconnected limbic network. Overall, we provide preliminary support for the hypothesis that altered disgust processing may serve as a transdiagnostic index of mental illness.

Alexithymia and asthma: a systematic review.

Growing evidence from scientific research elucidates the important role of alexithymia in chronic immune diseases. This Review aims to explore the presence of alexithymia in patients affected by asthma and clarify its associations with other involved psychological and physical factors. In January 2023, according to PRISMA guidelines, a systematic search using PubMed and Scopus was conducted. Twenty-six studies were eligible based on inclusion criteria. Alexithymia was significantly present in asthma patients, with most studies reporting a higher prevalence (from 9 to 62.8%) than in control groups (approximately 10%). The coexistence of asthma and alexithymia was associated with a worse quality of life, psychiatric comorbidity, poor symptom control, and difficulty in recognizing exacerbations of the disease. These results suggest that alexithymia can negatively impact the management of asthma. For this reason, we recommend an accuracy assessment in clinical settings and the implementation of psychological interventions to promote the emotional and physical wellbeing of asthmatic patients.

The Role of Serotonin in Fear Learning and Memory: A Systematic Review of Human Studies.

Fear is characterized by distinct behavioral and physiological responses that are essential for the survival of the human species. Fear conditioning (FC) serves as a valuable model for studying the acquisition, extinction, and expression of fear. The serotonin (5-hydroxytryptamine, 5-HT) system is known to play a significant role in emotional and motivational aspects of human behavior, including fear learning and expression. Accumulating evidence from both animal and human studies suggests that brain regions involved in FC, such as the amygdala, hippocampus, and prefrontal cortex, possess a high density of 5-HT receptors, implicating the crucial involvement of serotonin in aversive learning. Additionally, studies exploring serotonin gene polymorphisms have indicated their potential influence on FC. Therefore, the objective of this work was to review the existing evidence linking 5-HT with fear learning and memory in humans. Through a comprehensive screening of the PubMed and Web of Science databases, 29 relevant studies were included in the final review. These studies investigated the relationship between serotonin and fear learning using drug manipulations or by studying 5-HT-related gene polymorphisms. The results suggest that elevated levels of 5-HT enhance aversive learning, indicating that the modulation of serotonin 5-HT2A receptors regulates the expression of fear responses in humans. Understanding the role of this neurochemical messenger in associative aversive learning can provide insights into psychiatric disorders such as anxiety and post-traumatic stress disorder (PTSD), among others.

Social cognition in hyperkinetic movement disorders: a systematic review.

Numerous lines of research indicate that our social brain involves a network of cortical and subcortical brain regions that are responsible for sensing and controlling body movements. However, it remains unclear whether movement disorders have a systematic impact on social cognition. To address this question, we conducted a systematic review examining the influence of hyperkinetic movement disorders (including Huntington disease, Tourette syndrome, dystonia, and essential tremor) on social cognition. Following the PRISMA guidelines and registering the protocol in the PROSPERO database (CRD42022327459), we analyzed 50 published studies focusing on theory of mind (ToM), social perception, and empathy. The results from these studies provide evidence of impairments in ToM and social perception in all hyperkinetic movement disorders, particularly during the recognition of negative emotions. Additionally, individuals with Huntington's Disease and Tourette syndrome exhibit empathy disorders. These findings support the functional role of subcortical structures (such as the basal ganglia and cerebellum), which are primarily responsible for movement disorders, in deficits related to social cognition.

Experiments on real-life emotions challenge Ekman's model.

Ekman's emotions (1992) are defined as universal basic emotions. Over the years, alternative models have emerged (e.g. Greene and Haidt 2002; Barrett 2017) describing emotions as social and linguistic constructions. The variety of models existing today raises the question of whether the abstraction provided by such models is sufficient as a descriptive/predictive tool for representing real-life emotional situations. Our study presents a social inquiry to test whether traditional models are sufficient to capture the complexity of daily life emotions, reported in a textual context. The intent of the study is to establish the human-subject agreement rate in an annotated corpus based on Ekman's theory (Entity-Level Tweets Emotional Analysis) and the human-subject agreement rate when using Ekman's emotions to annotate sentences that don't respect the Ekman's model (The Dictionary of Obscure Sorrows). Furthermore, we investigated how much alexithymia can influence the human ability to detect and categorise emotions. On a total sample of 114 subjects, our results show low within subjects agreement rates for both datasets, particularly for subjects with low levels of alexithymia; low levels of agreement with the original annotations; frequent use of emotions based on Ekman model, particularly negative one, in people with high levels of alexithymia.

Interrelations between clinical-psychological features and bone mineral density changes in post-menopausal women undergoing anti-osteoporotic treatment: a two-year follow-up.

Introduction: Psychological features have been bidirectionally associated with osteoporosis, but it is still unclear whether patient's anxiety fluctuations during the anti-osteoporotic treatment can have an impact on bone mineral density (BMD) variation. The aim of this study was to investigate the interrelations between psychological distress features, such as anxiety, depression, health-related QoL (HRQoL) and bone health in women receiving anti-osteoporotic treatment. Methods: 192 post-menopausal osteoporotic women were treated with alendronate or risedronate according to the standard procedure. The levels of anxiety, depression, and perceived HRQoL, along with BMD, were assessed at baseline and at a 2-year follow-up. Results: At the end of the study, the patients showed a statistically significant increase of both psychic and somatic anxiety (p<0.0001) and exhibited a worsening of depressive symptoms (p<0.0001), whereas HRQoL showed no change. BMD improved and no incident fractures occurred. BMD variation (ΔBMD) at lumbar spine was significantly associated with anxiety levels (r=0.23, p=0.021). Multiple regression analysis showed that both patients' worsening anxiety levels (ß = -0.1283, SE=0.06142, p=0.04) and their treatment adherence (ß=0.09, SE=0.02, p=0.0006) were independently associated with ΔBMD. Discussion: The findings of the current follow-up study suggest that BMD in post-menopausal women undergoing anti-osteoporotic treatment was predicted by treatment adherence and anxiety change over time.

Non-Invasive Brain Stimulation for the Modulation of Aggressive Behavior-A Systematic Review of Randomized Sham-Controlled Studies.

INTRO: Aggressive behavior represents a significant public health issue, with relevant social, political, and security implications. Non-invasive brain stimulation (NIBS) techniques may modulate aggressive behavior through stimulation of the prefrontal cortex. AIMS: To review research on the effectiveness of NIBS to alter aggression, discuss the main findings and potential limitations, consider the specifics of the techniques and protocols employed, and discuss clinical implications. METHODS: A systematic review of the literature available in the PubMed database was carried out, and 17 randomized sham-controlled studies investigating the effectiveness of NIBS techniques on aggression were included. Exclusion criteria included reviews, meta-analyses, and articles not referring to the subject of interest or not addressing cognitive and emotional modulation aims. CONCLUSIONS: The reviewed data provide promising evidence for the beneficial effects of tDCS, conventional rTMS, and cTBS on aggression in healthy adults, forensic, and clinical samples. The specific stimulation target is a key factor for the success of stimulation on aggression modulation. rTMS and cTBS showed opposite effects on aggression compared with tDCS. However, due to the heterogeneity of stimulation protocols, experimental designs, and samples, we cannot exclude other factors that may play a confounding role.

A Quantum-Classical Model of Brain Dynamics.

The study of the human psyche has elucidated a bipartite structure of logic reflecting the quantum-classical nature of the world. Accordingly, we posited an approach toward studying the brain by means of the quantum-classical dynamics of a mixed Weyl symbol. The mixed Weyl symbol can be used to describe brain processes at the microscopic level and, when averaged over an appropriate ensemble, can provide a link to the results of measurements made at the meso and macro scale. Within this approach, quantum variables (such as, for example, nuclear and electron spins, dipole momenta of particles or molecules, tunneling degrees of freedom, and so on) can be represented by spinors, whereas the electromagnetic fields and phonon modes can be treated either classically or semi-classically in phase space by also considering quantum zero-point fluctuations. Quantum zero-point effects can be incorporated into numerical simulations by controlling the temperature of each field mode via coupling to a dedicated Nosé-Hoover chain thermostat. The temperature of each thermostat was chosen in order to reproduce quantum statistics in the canonical ensemble. In this first paper, we introduce a general quantum-classical Hamiltonian model that can be tailored to study physical processes at the interface between the quantum and the classical world in the brain. While the approach is discussed in detail, numerical calculations are not reported in the present paper, but they are planned for future work. Our theory of brain dynamics subsumes some compatible aspects of three well-known quantum approaches to brain dynamics, namely the electromagnetic field theory approach, the orchestrated objective reduction theory, and the dissipative quantum model of the brain. All three models are reviewed.

Neuropharmacological Modulation of N-methyl-D-aspartate, Noradrenaline and Endocannabinoid Receptors in Fear Extinction Learning: Synaptic Transmission and Plasticity.

Learning to recognize and respond to potential threats is crucial for survival. Pavlovian threat conditioning represents a key paradigm for investigating the neurobiological mechanisms of fear learning. In this review, we address the role of specific neuropharmacological adjuvants that act on neurochemical synaptic transmission, as well as on brain plasticity processes implicated in fear memory. We focus on novel neuropharmacological manipulations targeting glutamatergic, noradrenergic, and endocannabinoid systems, and address how the modulation of these neurobiological systems affects fear extinction learning in humans. We show that the administration of N-methyl-D-aspartate (NMDA) agonists and modulation of the endocannabinoid system by fatty acid amide hydrolase (FAAH) inhibition can boost extinction learning through the stabilization and regulation of the receptor concentration. On the other hand, elevated noradrenaline levels dynamically modulate fear learning, hindering long-term extinction processes. These pharmacological interventions could provide novel targeted treatments and prevention strategies for fear-based and anxiety-related disorders.

Evidence of abnormal scalar timing property in alexithymia.

Evidence suggests that incidental modulation of affective states affects the ability to keep track of time. Alexithymia represents an ideal condition to further address the emotion-time processing link, as it refers to a trait characterized by a deficit of affective processing. 31 healthy participants completed an online version of the TAS-20 scale, which measures alexithymia, and a time reproduction task of visual stimuli related to positive (i.e., happiness) and negative (i.e., anger) facial expressions. Results documented a positive correlation between TAS-20 score and the variability in reproducing sub-second durations of the anger expression stimuli We also found an overestimation of sub-second durations of non-affective expressions in borderline/alexithymic participants. Finally, in line with the literature, we confirmed the overall tendency to overestimate the duration of anger expression stimuli. These findings, which can be interpreted in terms of abnormal scalar timing property in alexithymia, expand previous investigations linking this personality trait with abnormal processing of negative emotions. The evidence that alexithymia predicts the reproduction variability of sub-second durations of negative affective stimuli corroborates previous neuroimaging studies documenting cerebellar deficits in these individuals.

Delay discounting in Parkinson's disease: A systematic review and meta-analysis.

Delay discounting refers to the depreciation of the value of a reward as a function of the time it takes to obtain it. Growing evidence shows altered delay discounting in several pathological conditions, including neurological disorders. Here, we conducted a systematic review and meta-analysis of the published literature on delay discounting (DD) in Parkinson's Disease (PD). We found steeper DD in patients with PD, compared to healthy controls, both in "on" and "off" dopaminergic medication. These results confirm altered DD in PD and suggest an independent influence of the dopaminergic medication and the clinical condition itself on it. Also the effect of impulse control disorder and of pharmacological treatments are analysed.