External error monitoring in subclinical obsessive-compulsive subjects: electrophysiological evidence from a Gambling Task

Therapeutic Efficacy of Reward Circuit‐Targeted Transcranial Magnetic Stimulation (TMS) on Suicidal Ideation in Depressed Patients: A Sham‐Controlled Trial of Two TMS Protocols

Background: Suicide is one of the leading causes of premature death, and dysfunctional reward processing may serve as a potential mechanism. However, effective treatment targeting reward circuits is rarely reported.

Objective: The present study investigated the therapeutic efficacy of two individualized protocols, repetitive transcranial magnetic stimulation (rTMS) and intermittent theta burst stimulation (iTBS), targeting the left dorsolateral prefrontal cortex (lDLPFC)–nucleus accumbens (NAcc) circuit on suicidal ideation among patients with major depressive disorder (MDD).

Methods: Here, 40 healthy controls (HCs) and 70 MDD patients (MDDs) were recruited for this double‐blinded, sham‐controlled clinical trial. The reward learning process during the Iowa gambling task (IGT) was initially measured at the baseline. Further, 62 MDDs were assigned to receive 15 daily sessions of individualized rTMS (n = 25), iTBS (n = 15), or sham treatment (n = 22) to the site of strongest lDLPFC–NAcc connectivity.

Results: We found MDDs demonstrated abnormalities in both IGT performance and reward‐associated event‐related potential (ERP) components compared to HCs. MDDs in the rTMS and iTBS groups showed significant improvements in suicidal ideation and anhedonia symptoms compared to the sham group. The rTMS group also exhibited a more negative‐going N170 and feedback‐related negativity (FRN) after treatment, and the increase in N170 absolute amplitude posttreatment showed a trend of correlation with improved Temporal Experience Pleasure Scales (TEPSs) and TEPS‐anticipatory (TEPS‐ant) scores.

Conclusion: The current study indicates that reward circuit‐based rTMS and iTBS showed comparable antisuicidal effects in depressive patients, suggesting that the lDLPFC–NAcc pathway may serve as a potential treatment target.

Trial Registration: ClinicalTrials.gov identifier: NCT03991572

Intermittent theta-burst stimulation combined with physical therapy as an optimal rehabilitation in Parkinson's disease: study protocol for a randomised, double-blind, controlled trial

BACKGROUND

First-line rehabilitative strategies to improve motor deficits are based on functional training (physical or occupational therapy), which has been demonstrated to facilitate neural reorganisation. Accumulating evidence suggests that non-invasive brain stimulation techniques, such as repetitive TMS (rTMS), may enhance neuroplasticity, thereby facilitating neural reorganisation and recovery from Parkinson's disease. Evidence also shows that intermittent theta-burst stimulation (iTBS) can improve motor function and quality of life in patients by promoting the excitability and neural remodelling of cerebral cortex. We aimed to combine iTBS stimulation with physiotherapy to improve the rehabilitation effect compared to physiotherapy alone in patients with Parkinson's disease.

METHODS

This randomised, double-blind clinical trial will enrol 50 Parkinson's disease patients aged 45-70 years with Hoehn and Yahr scale scores of 1-3. Patients are randomly assigned to either the iTBS + physiotherapy or sham-iTBS + physiotherapy group. The trial consists of a 2-week double-blind treatment period and a 24-week follow-up period. iTBS and sham-iTBS will be administered twice daily for 10 days based on physiotherapy. The primary outcome will be the third part of Movement Disorders-Unified Parkinson's Disease Rating Scale (MDS-UPDRS III) from the baseline to the first 2 days following completion hospitalised intervention. The secondary outcome will be 39-item Parkinson's Disease Questionnaire (PDQ-39) at 4 weeks, 12 weeks and 24 weeks after intervention. Tertiary outcomes are clinical evaluations and mechanism study outcomes such as NMSS, 6MWD, 10MT, TUG, BBS, MRI, and EEG, the length of time between the drug needs to be adjusted when symptoms fluctuate.

DISCUSSION

The aim of this study is to demonstrate that iTBS can promote overall function and quality of life in Parkinson's disease patients using physiotherapy and that this efficacy may be associated with altered neuroplasticity in exercise-related brain regions. The iTBS combined with physiotherapy training model will be evaluated during a 6-month follow-up period. With significant improvement in quality of life and motor function, iTBS combined with physiotherapy can be considered as a first-line rehabilitation option for Parkinson's disease. The potential of iTBS to enhance neuroplasticity in the brain should have a more positive impact in increasing the generality and efficiency of physiotherapy, improving the quality of life and overall functional status of patients with Parkinson's disease.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200056581. Registered on 8 February 2022.

High-Definition Transcranial Direct Current Stimulation Improves Decision-Making Ability: A Study Based on EEG

High-definition transcranial direct current stimulation (HD-tDCS) has been shown to modulate decision-making; however, the neurophysiological mechanisms underlying this effect remain unclear. To further explore the neurophysiological processes of decision-making modulated by HD-tDCS, health participants underwent ten anodal (n = 16)/sham (n = 17) HD-tDCS sessions targeting the left DLPFC. Iowa gambling task was performed simultaneously with electroencephalography (EEG) before and after HD-tDCS. Iowa gambling task performance, the P300 amplitude, and the power of theta oscillation as an index of decision-making were compared. Behavioral changes were found that showed anodal HD-tDCS could improve the decision-making function, in which participants could make more advantageous choices. The electrophysiological results showed that the P300 amplitude significantly increased in CZ, CPZ electrode placement site and theta oscillation power significantly activated in FCZ, CZ electrode placement site after anodal HD-tDCS. Significant positive correlations were observed between the changes in the percent use of negative feedback and the changes in theta oscillation power before and after anodal HD-tDCS. This study showed that HD-tDCS is a promising technology in improving decision-making and theta oscillation induced by may be a predictor of improved decision-making.

A systematic review and meta-analysis of altered electrophysiological markers of performance monitoring in Obsessive-Compulsive Disorder (OCD), Gilles de la Tourette Syndrome (GTS), Attention-Deficit/Hyperactivity disorder (ADHD) and Autism

Altered performance monitoring is implicated in obsessive-compulsive disorder (OCD), Gilles de la Tourette syndrome (GTS), attention-deficit/hyperactivity disorder (ADHD) and autism. We conducted a systematic review and meta-analysis of electrophysiological correlates of performance monitoring (error-related negativity, ERN; error positivity, Pe; feedback-related negativity, FRN; feedback-P3) in individuals with OCD, GTS, ADHD or autism compared to control participants, or associations between correlates and symptoms/traits of these conditions. Meta-analyses on 97 studies (5890 participants) showed increased ERN in OCD (Hedge's g = 0.54[CIs:0.44,0.65]) and GTS (g = 0.99[CIs:0.05,1.93]). OCD also showed increased Pe (g = 0.51[CIs:0.21,0.81]) and FRN (g = 0.50[CIs:0.26,0.73]). ADHD and autism showed reduced ERN (ADHD: g=-0.47[CIs:-0.67,-0.26]; autism: g=-0.61[CIs:-1.10,-0.13]). ADHD also showed reduced Pe (g=-0.50[CIs:-0.69,-0.32]). These findings suggest overlap in electrophysiological markers of performance monitoring alterations in four common neurodevelopmental conditions, with increased amplitudes of the markers in OCD and GTS and decreased amplitudes in ADHD and autism. Implications of these findings in terms of shared and distinct performance monitoring alterations across these neurodevelopmental conditions are discussed. PROSPERO pre-registration code: CRD42019134612.

Abnormal negative feedback processing in individuals with autistic traits in the Iowa gambling task: Evidence from behavior and event-related potentials

Value-based decision making plays an important role in social interaction. Previous studies have reported that individuals with autism spectrum disorder (ASD) exhibit deficits in terms of decision making. However, it is still unknown clearly whether individuals with high autistic traits within nonclinical populations employ abnormal neural substrates in value-based decision-making. To explore this issue, we investigated value-based decision making and its neural substrates in individuals with high and low autistic traits within a typically developing population who completed the revised Iowa gambling task (IGT) based on measurements of event-related potentials (ERPs). The IGT net scores were significantly lower in the group with high autistic traits than the group with low autistic traits in the fifth and sixth blocks. The ERP results showed that the feedback-related negativity (FRN) amplitude in individuals with high autistic traits allowed slight discrimination between positive and negative feedback in the low-risk option. The event-related spectral perturbations (ERSPs) and inter-trial coherence (ITC) of the theta-band frequency were also lower in the group with high autistic traits than the group with low autistic traits in the loss low-risk option. The results obtained in this study indicate that individuals with high autistic traits exhibit an unusual negative feedback process and relevant neural substrate. The FRN amplitude and theta-band oscillation may comprise a neural index of abnormal decision-making processes in individuals with high autistic traits. This study of a small sample may be considered an important step toward a more comprehensive understanding of the autism "spectrum" within a nonclinical population based on cognitive neuroscience.

Intermittent Theta Burst Stimulation (iTBS) as an Optimal Treatment for Schizophrenia Risk Decision: an ERSP Study

Objective: People with schizophrenia have serious impairments in social function, especially in decision-making ability. Transcranial magnetic stimulation modified intermittent theta burst transcranial magnetic stimulation (iTBS) has been shown to regulate the functional connection of brain networks. Our study explored the therapeutic effect of iTBS on decision-making disorders in schizophrenia. Methods: Participants were pseudorandomized and assigned to iTBS (n = 16) or sham (n = 16) group. iTBS group was administered 1,800 pulses on the target of the left dorsol lateral prefrontal cortex (L-DLPFC) per day for 14 consecutive days. We compared Iowa gambling task performance and associated event-related spectral perturbation results (ERSP) among two groups. Results: The results show that participants' performance in the high-lose in the iTBS group had stronger stimulation of theta spectral power than those in the sham group. Specifically, we found that under high-risk conditions, compared with the control group, the iTBS group showed significant activation of the theta spectrum power in the FPZ, FZ, FCZ, and CZ regions after treatment. Conclusions: Our results provide evidence that long-term iTBS stimulation effectively improves the decision-making ability of schizophrenia. After receiving negative feedback, patients can turn to safety options. These findings support that iTBS may be a potential treatment for clinical decision-making disorders.

Do Individuals With Obsessive-Compulsive Disorder and Obsessive-Compulsive Personality Disorder Share Similar Neural Mechanisms of Decision-Making Under Ambiguous Circumstances?

Impaired decision-making is well documented in obsessive-compulsive disorder (OCD) and a range of electrophysiological and functional neuroimaging measures have begun to reveal the pathological mechanisms that underlie the decision-making process. Obsessive-compulsive personality disorder (OCPD) has core symptoms that often overlap with OCD, but similarities between these disorders at the behavioral and neurological levels are often unclear, including whether OCPD exhibits similar decision-making deficits and shared neurological dysfunction. To address these issues, we examined 24 cases of OCD, 19 cases of OCPD, and 26 matched normal control (NC) subjects during the revised Iowa Gambling Task (IGT) using event-related potentials (ERPs). The net IGT scores were lower for OCD subjects than for OCPD or NC subjects, thus indicating that OCD subjects chose more disadvantageous options and were "short-sighted" with regards to information. The feedback-related negativity (FRN) waveform (lose-win) was larger in both OCD and OCPD subjects, which suggested that obstacles exist in the feedback process. Consequently, these subjects might share similar neural mechanisms under ambiguous decision-making circumstances. Furthermore, IGT net scores were significantly and negatively correlated with Hamilton Anxiety Rating Scale (HAMA) and Hamilton Depression Rating Scale (HAMD) scales. This implies that more severe obsessive-compulsive symptoms inspired more negative emotions that led to worse decision-making ability. Therefore, although similar neural mechanisms might exist, this led to different behaviors in which OCPD is associated with better behavioral performance compared to OCD patients.

Internal and external signal processing in patients with panic disorder: An event-related potential (ERP) study

Self-absorption describes a pathological tendency towards the internal mental world (internalization) that often conflicts with the accurate monitoring of the external world. In performance monitoring, an augmented electrophysiological response evoked by internal signals in patients with anxiety or depressive disorder seems to reflect this tendency. Specifically, the error-related negativity (Ne/ERN), an index of error processing based on internal signals, is larger in patients compared to controls. In the present experiment, we investigated whether the preferential processing of internal signals in patients is linked to diminished and inflexible external signal processing. To this end, the electrophysiological response evoked by external signals was analysed in patients with panic disorder and healthy controls. Participants performed a choice-response task, where informative or uninformative feedback followed each response, and a passive viewing task. As a replication of previous studies, patients presented an augmented Ne/ERN, indexing enhanced processing of internal signals related to errors. Furthermore, the vertex positive potential (VPP) evoked by visual stimuli was larger in patients than in controls, suggesting enhanced attention to external signals. Moreover, patients and controls showed similar sensitivity to the feedback information content, indicating a normal flexibility in the allocation of monitoring resources to external signals depending on how informative these signals are for performance monitoring. These results suggest that the tendency towards internal signals in patients with panic disorder does not hinder the flexible processing of external signals. On the contrary, external signals seem to attract enhanced processing in patients compared to controls.

Event-Related Potentials in Relation to Risk-Taking: A Systematic Review

Event-related potentials (ERPs) have been used to investigate neural mechanisms underlying risk-related decisions over the last 16 years. We aimed to systematically evaluate associations between risk-taking and ERP components elicited during decisions and following feedback. A total of 79 articles identified from PsychINFO and PubMed databases met the inclusion criteria. Selected articles assessed early ERP components (feedback-related negativity/FRN, error-related negativity/ERN, and medial frontal negativity/MFN) and the mid-latency P3 component, all using gambling paradigms that involved selecting between choices of varying risk (e.g., Iowa Gambling Task, Balloon Analogue Risk Task, and two-choice gambling tasks). The P3 component was consistently enhanced to the selection of risky options and when positive feedback (as compared to negative feedback) was provided. Also consistently, the early negative components were found to be larger following feedback indicating monetary losses as compared to gains. In the majority of studies reviewed here, risk was conceptualized in the context of simple economical decisions in gambling tasks. As such, this narrow concept of risk might not capture the diversity of risky decisions made in other areas of everyday experience, for example, social, health, and recreational risk-related decisions. It therefore remains to be seen whether the risk-sensitivity of the ERP components reviewed here generalizes to other domains of life.

Reliability of the electrocortical response to gains and losses in the doors task

The ability to differentiate between rewards and losses is critical for motivated action, and aberrant reward and loss processing has been associated with psychopathology. The reward positivity (RewP) and feedback negativity (FN) are ERPs elicited by monetary gains and losses, respectively, and are promising individual difference measures. However, few studies have reported on the psychometric properties of the RewP and FN-crucial characteristics necessary for valid individual difference measures. The current study examined the internal consistency and 1-week test-retest reliability of the RewP and FN as elicited by the doors task among 59 young adults. The RewP, FN, and their difference score (ΔRewP) all showed significant correlations between Time 1 and Time 2. The RewP and FN also achieved acceptable internal consistency at both time points within 20 trials using both Cronbach's α and a generalizability theory-derived dependability measure. Internal consistency for ΔRewP was notably weaker at both time points, which is expected from two highly intercorrelated constituent scores. In conclusion, the RewP and FN have strong psychometric properties in a healthy adult sample. Future research is needed to assess the psychometric properties of these ERPs in different age cohorts and in clinical populations.

Pick a Card, Any Card: The Relationship Between Anxiety, Obsessive-Compulsive Symptoms and Decision-Making

Specific deficits in decision-making have been demonstrated in patients with obsessive-compulsive disorder (OCD). The experience of anxious arousal in obsessive-compulsive (OC) patients has been posited to be responsible for disrupting the cognitive processes that lead to efficacious decision-making (Sachdev & Malhi, 2005). In spite of this, research has neglected to examine explicitly the effect of anxiety on the relationship between decision-making and OCD. The current study investigates whether decision-making differences on the Iowa Gambling Task (IGT) occur as a function of OC symptomatology in a non-clinical sample (n = 110). Participants were randomly allocated to either an anxiety condition (n = 58) or control condition (n = 52). Anxious arousal was induced in the anxiety condition via an experimental manipulation prior to commencing the IGT. Participants in the anxiety condition performed significantly worse than those in the control group on the IGT. However, OC symptomatology did not significantly predict IGT performance. The experience of anxiety did not significantly moderate the relationship between OC symptomatology and IGT performance. These findings indicate that decision-making differences do not occur as a function of OC symptomatology in a non-clinical sample; however, they do suggest that the experience of anxiety significantly impairs decision-making performance. The theoretical and practical applications of the findings are discussed.

Executive functions as a potential neurocognitive endophenotype in anxiety disorders: A systematic review considering DSM-IV and DSM-5 diagnostic criteria classification

Evidence in the literature indicates that neurocognitive impairments may represent endophenotypes in psychiatric disorders.

Objective

This study aimed to conduct a systematic review on executive functions as a potential neurocognitive endophenotype in anxiety disorder diagnosis according to the DSM-IV and DSM-5 classifications.

Methods

A literature search of the LILACS, Cochrane Library, Index Psi Periódicos Técnico-Científicos, PubMed and PsycInfo databases was conducted, with no time limits. Of the 259 studies found, 14 were included in this review.

Results

Only studies on obsessive-compulsive disorder (OCD) were found. The executive function components of decision-making, planning, response inhibition, behavioral reversal/alternation, reversal learning and set-shifting/cognitive flexibility were considered to be a neurocognitive endophenotypes in OCD.

Conclusion

Further studies on executive functions as a neurocognitive endophenotype in other anxiety disorders are needed since these may have different neurocognitive endophenotypes and require other prevention and treatment approaches.