Effects of High-Frequency Transcranial Magnetic Stimulation for Cognitive Deficit in Schizophrenia: A Meta-Analysis

Predictors of psychosocial functioning in people diagnosed with schizophrenia spectrum disorders that committed violent offences and in those that did not: Results of the Recoviwel study

Psychosocial functioning represents a core treatment target of Schizophrenia Spectrum Disorders (SSD), and several clinical and cognitive factors contribute to its impairment. However, determinants of psychosocial functioning in people living with SSD that committed violent offences remain to be more thoroughly explored. This study aims to separately assess and compare predictors of psychosocial functioning in people with SSD that did and that did not commit violent offences considering several clinical, cognitive and violence-related parameters. Fifty inmates convicted for violent crimes in a forensic psychiatry setting diagnosed with SSD (OP group) and fifty participants matched for age, gender, education, and diagnosis (Non-OP group) were included in the study. A higher risk of violent relapse as measured by HCR-20 clinical subscale scores (p < 0.002) and greater global clinical severity as measured by CGI-S scores (p = 0.023) emerged as individual predictors of worse psychosocial functioning, as measured by PSP scores, in the OP group. Greater global clinical severity (p < 0.001), worse performance in the processing speed domain as measured by the BACS Symbol Coding (p = 0.002) and TMT-A tests (p = 0.016) and higher levels of non-planning impulsivity as measured by BIS-11 scores (p < 0.001) emerged as individual predictors of worse psychosocial functioning in the Non-OP group. These results confirm that clinical severity impacts psychosocial functioning in all individuals diagnosed with SSD and suggest that while cognitive impairment clearly represents a determinant of worse functional outcomes in most patients, the risk of violent relapse is a specific predictor of worse psychosocial functioning in people with SSD that committed criminal offences.

Prolonged intermittent theta burst stimulation targeting the left prefrontal cortex and cerebellum does not affect executive functions in healthy individuals

Repetitive transcranial magnetic stimulation (rTMS) for alleviating negative symptoms and cognitive dysfunction in schizophrenia commonly targets the left dorsolateral prefrontal cortex (LDLPFC). However, the therapeutic effectiveness of rTMS at this site remains inconclusive and increasingly, studies are focusing on cerebellar rTMS. Recently, prolonged intermittent theta-burst stimulation (iTBS) has emerged as a rapid-acting form of rTMS with promising clinical benefits. This study explored the cognitive and neurophysiological effects of prolonged iTBS administered to the LDLPFC and cerebellum in a healthy cohort. 50 healthy participants took part in a cross-over study and received prolonged (1800 pulses) iTBS targeting the LDLPFC, cerebellar vermis, and sham iTBS. Mixed effects repeated measures models examined cognitive and event-related potentials (ERPs) from 2-back (P300, N200) and Stroop (N200, N450) tasks after stimulation. Exploratory non-parametric cluster-based permutation tests compared ERPs between conditions. There were no significant differences between conditions for behavioural and ERP outcomes on the 2-back and Stroop tasks. Exploratory cluster-based permutation tests of ERPs did not identify any significant differences between conditions. We did not find evidence that a single session of prolonged iTBS administered to either the LDLPFC or cerebellum could cause any cognitive or ERP changes compared to sham in a healthy sample.

High-Frequency Repetitive Transcranial Magnetic Stimulation on Overall Cognition in Patients With Poststroke Cognitive Impairment: A Systematic Review and Meta-analysis

OBJECTIVE

The aim of the study is to comprehensively assess the recovery effects of high-frequency repetitive transcranial magnetic stimulation in patients with poststroke cognitive impairment.

METHODS

Six English and four Chinese databases were searched for relevant studies published up to January 2022. Randomized controlled trials of patients with poststroke cognitive impairment treated with high-frequency repetitive transcranial magnetic stimulation were included. Included studies were assessed for the risk of bias through the Cochrane Intervention Systematic Review Manual 5.1.0. The meta-analysis was performed using RevMan 5.4 software. The PRISMA 2020 guidelines were followed.

RESULTS

Sixty-one randomized controlled trials (4012 patients) were included. Montreal Cognitive Assessment Score, Mini-Mental State Examination score, event-related potential P300 (P300) amplitude, Loewenstein Occupational Therapy Cognitive Assessment score, and total effective rate of cognitive function were higher in the high-frequency repetitive transcranial magnetic stimulation group than in the control group at the end of the treatment period, and scores of Alzheimer Disease Assessment Scale-Cognitive Subscale and P300 latency were lower in the high-frequency repetitive transcranial magnetic stimulation group than in the control group. Fifty studies had selected the dorsolateral prefrontal cortex as the stimulation site for high-frequency repetitive transcranial magnetic stimulation.

CONCLUSIONS

Compared with nonrepetitive transcranial magnetic stimulation or sham repetitive transcranial magnetic stimulation, high-frequency repetitive transcranial magnetic stimulation not only improves the overall cognitive function of poststroke cognitive impairment patients but also has better rehabilitation results.

Individualised Transcranial Magnetic Stimulation Targeting of the Left Dorsolateral Prefrontal Cortex for Enhancing Cognition: A Randomised Controlled Trial

Repetitive transcranial magnetic stimulation (rTMS) has been demonstrated to produce cognitive enhancing effects across different neuropsychiatric disorders; however, so far, these effects have been limited. This trial investigated the efficacy of using a novel individualised approach to target the left dorsolateral prefrontal cortex (L-DLPFC) for enhancing cognitive flexibility based on performance on a cognitive task. First, forty healthy participants had their single target site at the L-DLPFC determined based on each individual's performance on a random letter generation task. Participants then received, in a cross-over single-blinded experimental design, a single session of intermittent theta burst stimulation (iTBS) to their individualised DLPFC target site, an active control site and sham iTBS. Following each treatment condition, participants completed the Task Switching task and Colour-Word Stroop test. There was no significant main effect of treatment condition on the primary outcome measure of switch reaction times from the Task Switching task [F = 1.16 (2, 21.6), p = 0.33] or for any of the secondary cognitive outcome measures. The current results do not support the use of our novel individualised targeting methodology for enhancing cognitive flexibility in healthy participants. Research into alternative methodological targeting approaches is required to further improve rTMS's cognitive enhancing effects.

Repetitive Transcranial Magnetic Stimulation for Working Memory Deficits in Schizophrenia: A Systematic Review of Randomized Controlled Trials

Working memory (WM) deficits are a significant component of neurocognitive impairment in individuals with schizophrenia (SCZ). Two previous meta-analyses, conducted on randomized controlled trials (RCTs), examined the effectiveness of repetitive transcranial magnetic stimulation (rTMS) in addressing WM deficits in individuals diagnosed with SCZ. However, the conclusions drawn from these analyses were inconsistent. Additionally, the commonly used random effects (RE) models might underestimate statistical errors, attributing a significant portion of perceived heterogeneity between studies to variations in study quality. Therefore, this review utilized both RE and quality effects (QE) models to assess relevant RCTs comparing TMS with sham intervention in terms of clinical outcomes. A comprehensive literature search was conducted using PubMed and Scopus databases, resulting in the inclusion of 13 studies for data synthesis. Overall, regardless of whether the RE or QE model was used, eligible RCTs suggested that the TMS and sham groups exhibited comparable therapeutic effects after treatment. The current state of research regarding the use of rTMS as a treatment for WM deficits in patients with SCZ remains in its preliminary phase. Furthermore, concerning the mechanism of action, the activation of brain regions focused on the dorsolateral prefrontal cortex and alterations in gamma oscillations may hold significant relevance in the therapeutic application of rTMS for addressing WM impairments. Finally, we believe that the application of closed-loop neuromodulation may contribute to the optimization of rTMS for WM impairment in patients with SCZ.

Effects of bilateral repetitive transcranial magnetic stimulation on prospective memory in patients with schizophrenia: A double-blind randomized controlled clinical trial

AIMS

To investigate effects of repetitive transcranial magnetic stimulation (rTMS) on the prospective memory (PM) in patients with schizophrenia (SCZ).

METHODS

Fifty of 71 patients completed this double-blind placebo-controlled randomized trial and compared with 18 healthy controls' (HCs) PM outcomes. Bilateral 20 Hz rTMS to the dorsolateral prefrontal cortex at 90% RMT administered 5 weekdays for 4 weeks for a total of 20 treatments. The Positive and Negative Symptom Scale (PANSS), the Scale for the Assessment of Negative Symptoms (SANS), and PM test were assessed before and after treatment.

RESULTS

Both Event-based PM (EBPM) and Time-based PM (TBPM) scores at baseline were significantly lower in patients with SCZ than that in HCs. After rTMS treatments, the scores of EBPM in patients with SCZ was significantly improved and had no differences from that in HCs, while the scores of TBPM did not improved. The negative symptom scores on PANSS and the scores of almost all subscales and total scores of SANS were significantly improved in both groups.

CONCLUSIONS

Our findings indicated that bilateral high-frequency rTMS treatment can alleviate EBPM but not TBPM in patients with SCZ, as well as improve the negative symptoms.

SIGNIFICANCE

Our results provide one therapeutic option for PM in patients with SCZ.

Efficacy of repetitive transcranial magnetic stimulation (rTMS) on negative symptoms and cognitive functioning in schizophrenia: An umbrella review of systematic reviews and meta-analyses

Negative symptoms and cognitive dysfunction are core characteristics of schizophrenia that profoundly impact daily function and quality of life. As a noninvasive brain stimulation, repetitive transcranial magnetic stimulation (rTMS) has been proposed as a relatively new treatment for ameliorating negative symptoms and cognitive dysfunction in schizophrenia. However, there is controversy over the treatment methods and efficacy. We aimed to provide a quantitative integration of the published evidence regarding the efficacy of rTMS and analyze the feasibility of rTMS for treating negative symptoms and cognitive dysfunction in schizophrenia. A total of twenty reviews were ultimately selected and divided into thirty-three latitudes. Twenty-six analyses showed that rTMS significantly decreased the negative symptom score, and seventeen analyses were performed. Six analyses showed that rTMS treatment can increase working memory scores, and two of them had significant effects. Two analyses from the same review showed that rTMS had a long-term significant effect on treating language function. Only one analysis showed that rTMS had a significant effect on treating executive function. The analyses showed that rTMS had no significant effect on attention function and processing speed. Most reviews indicate that rTMS has an effect on negative symptoms, executive function, working memory, and language function in patients with schizophrenia. Although the quality of evidence was not high, these results are still positive and worthwhile for further study.

Combining transcranial magnetic stimulation with training to improve social cognition impairment in schizophrenia: a pilot randomized controlled trial

Schizophrenia is a severe, chronic mental disorder that profoundly impacts patients' everyday lives. The illness's core features include positive and negative symptoms and cognitive impairments. In particular, deficits in the social cognition domain showed a tighter connection to patients' everyday functioning than the other symptoms. Social remediation interventions have been developed, providing heterogeneous results considering the possibility of generalizing the acquired improvements in patients' daily activities. In this pilot randomized controlled trial, we investigated the feasibility of combining fifteen daily cognitive and social training sessions with non-invasive brain stimulation to boost the effectiveness of the two interventions. We delivered intermittent theta burst stimulation (iTBS) over the left dorsolateral prefrontal cortex (DLPFC). Twenty-one patients were randomized into four groups, varying for the assigned stimulation condition (real vs. sham iTBS) and the type of cognitive intervention (training vs. no training). Clinical symptoms and social cognition tests were administered at five time points, i.e., before and after the treatment, and at three follow-ups at one, three, and six months after the treatments' end. Preliminary data show a trend in improving the competence in managing emotion in participants performing the training. Conversely, no differences were found in pre and post-treatment scores for emotion recognition, theory of mind, and attribution of intentions scores. The iTBS intervention did not induce additional effects on individuals' performance. The methodological approach's novelty and limitations of the present study are discussed.

The cognitive improvement in patients with schizophrenia following low-intensity repetitive transcranial magnetic stimulation could last for 6 months: A randomized controlled trial

Cognitive impairments are a core symptom of schizophrenia. Although low-intensity repetitive transcranial magnetic stimulation (rTMS) also has cognitive improving effect like the commonly used high-intensity rTMS, it has not been applied in schizophrenia yet. To fill this gap, inpatients with schizophrenia were randomized to receive 20 sessions of daily adjunctive active low-intensity rTMS in 4 weeks, or sham treatment. At baseline, 4 weeks, and 6 months, the Positive and Negative Syndrome Scale (PANSS) was used to assess psychotic symptom severity, while the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Stroop Color and Word Test (SCWT) were used to assess cognitive functions. Compared to the sixty-nine patients receiving sham treatment, those fifty-nine patients receiving active rTMS performed better in all cognitive domains at post-treatment with small to large effect sizes. This superiority of active rTMS over sham treatment remained significant at 6-month follow-up, with small to large effect sizes, except for visuospatial function and delayed memory. The reduction in PANSS scores were not correlated with cognitive improvements. Our findings provide evidence for using low-intensity rTMS to ameliorate cognitive impairments in schizophrenia. More research are needed to determine the optimal intensity for each domain of cognitive functions.

Pre-clinical indications of brain stimulation treatments for non-affective psychiatric disorders, a status update

Over the past two decades noninvasive brain stimulation (NIBS) techniques have emerged as powerful therapeutic options for a range of psychiatric and neurological disorders. NIBS are hypothesized to rebalance pathological brain networks thus reducing symptoms and improving functioning. This development has been fueled by controlled studies with increasing size and rigor aiming to characterize how treatments induce clinically effective change. Clinical trials of NIBS for specific indications have resulted in federal approval for unipolar depression, bipolar depression, smoking cessation, and obsessive-compulsive disorder in the United States, and several other indications worldwide. As a rapidly emerging field, there are numerous pre-clinical indications currently in development using a variety of electrical and magnetic, non-convulsive, and convulsive approaches. This review discusses the state-of-the-science surrounding promising avenues of NIBS currently in pre-approval stages for non-affective psychiatric disorders. We consider emerging therapies for psychosis, anxiety disorders, obsessive-compulsive disorder, and borderline personality disorder, utilizing transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and magnetic seizure therapy (MST), with an additional brief section for early-stage techniques including transcranial focused ultrasound stimulation (tFUS) and transcranial alternating current stimulation (tACS). As revealed in this review, there is considerable promise across all four psychiatric indications with different NIBS approaches. Positive findings are notable for the treatment of psychosis using tDCS, MST, and rTMS. While rTMS is already FDA approved for the treatment of obsessive-compulsive disorder, methodologies such as tDCS also demonstrate potential in this condition. Emerging techniques show promise for treating non-affective disorders likely leading to future regulatory approvals.

Effects of intermittent theta-burst transcranial magnetic stimulation on cognition and hippocampal volumes in bipolar depression

INTRODUCTION

Repetitive transcranial magnetic stimulation (TMS) is increasingly used to treat neurocognitive symptoms in mood disorders. Intermittent theta burst stimulation (iTBS) is a brief version of TMS that may preferentially target cognitive functions. This study evaluated whether iTBS leads to cognitive improvements and associated increased hippocampal volumes in bipolar depression.

METHODS

In a two-site double-blind randomised sham controlled trial (NCT02749006), 16 patients received active iTBS to the Left Dorsolateral Prefrontal Cortex (DLPF) and 15 patients received sham stimulation across four weeks. A composite neuropsychological score and declarative memory scores served as the cognitive outcomes. Hippocampal volumes were derived from T1 weighted MRI scans using the longitudinal ComBat method to harmonise data across sites.

RESULTS

No significant improvements were observed in any cognitive variables in the active relative to the sham group; however, there was a trend for increased left hippocampal volume in the former. Left hippocampal volume increases were associated with improvements in nonverbal memory in the active group.

CONCLUSIONS

Although cognitive improvements were not associated with iTBS, the finding that hippocampal volume increases were associated with memory improvement suggests there may be some level of prefrontal-temporal neuroplasticity that could support cognitive change in future studies of iTBS in bipolar disorder.

Altered Associations Between Task Performance and Dorsolateral Prefrontal Cortex Activation During Cognitive Control in Schizophrenia

BACKGROUND

Dysfunctional cognitive control processes are now well understood to be core features of schizophrenia (SZ). A body of work suggests that the dorsolateral prefrontal cortex (DLPFC) plays a critical role in explaining cognitive control disruptions in SZ. Here, we examined relationships between DLPFC activation and drift rate (DR), a model-based performance measure that combines reaction time and accuracy, in people with SZ and healthy control (HC) participants.

METHODS

One hundred fifty-one people with recent-onset SZ spectrum disorders and 118 HC participants performed the AX-Continuous Performance Task during functional magnetic resonance imaging scanning. Proactive cognitive control-associated activation was extracted from left and right DLPFC regions of interest. Individual behavior was fit using a drift diffusion model, allowing DR to vary between task conditions.

RESULTS

Behaviorally, people with SZ showed significantly lower DRs than HC participants, particularly during high proactive control trial types ("B" trials). Recapitulating previous findings, the SZ group also demonstrated reduced cognitive control-associated DLPFC activation compared with HC participants. Furthermore, significant group differences were also observed in the relationship between left and right DLPFC activation with DR, such that positive relationships between DR and activation were found in HC participants but not in people with SZ.

CONCLUSIONS

These results suggest that DLPFC activation is less associated with cognitive control-related behavioral performance enhancements in SZ. Potential mechanisms and implications are discussed.

A pilot study to examine the association between COX-2 rs5275 polymorphism and the response to repetitive transcranial stimulation in schizophrenia

High frequency (HF)-rTMS has been shown to improve cognitive functions in patients with schizophrenia (SCZ). This study aimed to investigate whether COX-2 rs5275 variants were associated with cognitive improvements following rTMS treatment in patients with SCZ. Forty-eight hospitalized patients with SCZ were assigned to the neuronavigation HF-rTMS group and 28 patients to the sham group over left DLPFC for 1 month. Cognitive function was evaluated using the repeatable battery for the assessment of neuropsychological status (RBANS) at weeks 0 and 4. COX-2 rs5275 polymorphism was genotyped by a technician. At baseline, C allele carriers showed better cognitive performance relative to patients with TT homozygote. Additionally, C allele carriers had greater improvement in memory from the follow-up to baseline following rTMS stimulation, while patients with the TT genotype showed no significant improvement in memory index. More importantly, we found that COX-2 rs5275 was correlated with the response to rTMS after controlling for the covariates. This study data indicate that COX-2 rs5275 was associated with improvements in immediate memory after HF-rTMS treatment in patients with SCZ. rTMS shows an effect on memory only in C allele carriers, but not in those with the TT genotype.

10 Hz repetitive transcranial magnetic stimulation (rTMS) may improve cognitive function: An exploratory study of schizophrenia patients with auditory hallucinations

Objectives

Cognitive impairment in schizophrenia patients with auditory hallucinations is more prominent compared to those without. Our study aimed to investigate the cognitive improvement effects of 10 Hz repetitive transcranial magnetic stimulation (rTMS) over the left dorsolateral prefrontal cortex (DLPFC) in schizophrenia with auditory hallucinations.

Methods

A total of 60 schizophrenic patients with auditory hallucinations in this study were randomly assigned to sham or active group. Both groups received 10 Hz or sham rTMS targeted in left DLPFC for 20 sessions. The Positive and Negative Syndrome Scale (PANSS), the Auditory Hallucination Rating Scale (AHRS), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and the Udvalg for Kliniske Under-sogelser (UKU) side effect scale were used to measure psychiatric symptoms, auditory hallucinations, cognition, and side reaction, respectively.

Results

Our results indicated that the active group experienced greater improvements in RBANS-total score (P = 0.043) and immediate memory subscale score (P = 0.001). Additionally, the PANSS-total score, negative and positive subscale score were obviously lower in the active group compared to the sham group (all P < 0.050). Furthermore, our study found that the improvement of RBANS-total score was positively associated with the decline of positive factor score, and the improvement of language score in RBANS was positively associated with the reduction in PANSS-total scale, negative and positive subscale score in the real stimulation group (all P < 0.050).

Conclusion

Our results demonstrated that a four-week intervention of 10 Hz rTMS over the left DLPFC can improve cognition (particularly immediate memory) among schizophrenia patients with auditory hallucinations. Future studies with larger sample size are needful to verify our preliminary findings.

Symptom-circuit mappings of the schizophrenia connectome

OBJECTIVE

This paper aims to model the anatomical circuits underlying schizophrenia symptoms, and to explore patterns of abnormal connectivity among brain networks affected by psychopathology.

METHODS

T1 magnetic resonance imaging (MRI), diffusion weighted imaging (DWI), and resting-state functional MRI (rsfMRI) were obtained from a total of 126 patients with schizophrenia who were recruited for the study. The images were processed using the Omniscient software (https://www.o8t. com). We further apply the use of the Hollow-tree Super (HoTS) method to gain insights into what brain regions had abnormal connectivity that might be linked to the symptoms of schizophrenia.

RESULTS

The Positive and Negative Symptom Scale is characterised into 6 factors. Each symptom is mapped with specific anatomical abnormalities and circuits. Comparison between factors reveals co-occurrence in parcels in Factor 1 and Factor 2. Multiple large-scale networks are involved in SCZ symptomatology, with functional connectivity within Default Mode Network (DMN) and Central Executive Network (CEN) regions most frequently associated with measures of psychopathology.

CONCLUSION

We present a summary of the relevant anatomy for regions of the cortical areas as part of a larger effort to understand its contribution in schizophrenia. This unique machine learning-type approach maps symptoms to specific brain regions and circuits by bridging the diagnostic subtypes and analysing the features of the connectome.

Language abnormalities in schizophrenia: binding core symptoms through contemporary empirical evidence

Both the ability to speak and to infer complex linguistic messages from sounds have been claimed as uniquely human phenomena. In schizophrenia, formal thought disorder (FTD) and auditory verbal hallucinations (AVHs) are manifestations respectively relating to concrete disruptions of those abilities. From an evolutionary perspective, Crow (1997) proposed that "schizophrenia is the price that Homo sapiens pays for the faculty of language". Epidemiological and experimental evidence points to an overlap between FTD and AVHs, yet a thorough investigation examining their shared neural mechanism in schizophrenia is lacking. In this review, we synthesize observations from three key domains. First, neuroanatomical evidence indicates substantial shared abnormalities in language-processing regions between FTD and AVHs, even in the early phases of schizophrenia. Second, neurochemical studies point to a glutamate-related dysfunction in these language-processing brain regions, contributing to verbal production deficits. Third, genetic findings further show how genes that overlap between schizophrenia and language disorders influence neurodevelopment and neurotransmission. We argue that these observations converge into the possibility that a glutamatergic dysfunction in language-processing brain regions might be a shared neural basis of both FTD and AVHs. Investigations of language pathology in schizophrenia could facilitate the development of diagnostic tools and treatments, so we call for multilevel confirmatory analyses focused on modulations of the language network as a therapeutic goal in schizophrenia.

Maintaining functional working memory through job activities: A study among patients with schizophrenia enrolled in a supported employment program

BACKGROUND: Employment is crucial in rehabilitation of patients with schizophrenia. It may have positive effects on cognitive function, including working memory. OBJECTIVE: The objective of this study was to look for evidence to confirm continuous job activities could maintain functional working memory in patients with schizophrenia. METHODS: This was a cross-sectional study involving patients with schizophrenia enrolled in supported employment (SE) program. Informed consent was obtained. Socio-demographic, employment, and clinical data were acquired from interview and clinical notes. Mini International Neuropsychiatric Inventory (M.I.N.I) was used to confirm the diagnosis of schizophrenia. Working memory was evaluated using Weschler Memory Scale Third Edition -Letter-Number Span and Spatial Span. RESULTS: 118 patients were recruited with a mean age of 43.76 years old (SD = 8.96). Most were male, Malays, Muslims, single, and received at least secondary education. There was a significant association between working memory and employment outcome (χ 2 = 20.835, p <  .001), and past work history (χ 2 = 10.077, p = 0.002). Multiple logistic regression indicated that the employment outcome (adjusted OR: 12.50; 95% CI: 2.55–61.21; p = 0.002) and past work history (adjusted OR: 3.36; 95% CI: 1.05–10.70; p = 0.041) were significant predictors of working memory among patients with schizophrenia in SE program. CONCLUSION: This study indicated that continuous job activities could maintain functional working memory in patients with schizophrenia.

Reconfiguration of Functional Dynamics in Cortico-Thalamo-Cerebellar Circuit in Schizophrenia Following High-Frequency Repeated Transcranial Magnetic Stimulation

Schizophrenia is a serious mental illness characterized by a disconnection between brain regions. Transcranial magnetic stimulation is a non-invasive brain intervention technique that can be used as a new and safe treatment option for patients with schizophrenia with drug-refractory symptoms, such as negative symptoms and cognitive impairment. However, the therapeutic effects of transcranial magnetic stimulation remain unclear and would be investigated using non-invasive tools, such as functional connectivity (FC). A longitudinal design was adopted to investigate the alteration in FC dynamics using a dynamic functional connectivity (dFC) approach in patients with schizophrenia following high-frequency repeated transcranial magnetic stimulation (rTMS) with the target at the left dorsolateral prefrontal cortex (DLPFC). Two groups of schizophrenia inpatients were recruited. One group received a 4-week high-frequency rTMS together with antipsychotic drugs (TSZ, n = 27), while the other group only received antipsychotic drugs (DSZ, n = 26). Resting-state functional magnetic resonance imaging (fMRI) and psychiatric symptoms were obtained from the patients with schizophrenia twice at baseline (t1) and after 4-week treatment (t2). The dynamics was evaluated using voxel- and region-wise FC temporal variability resulting from fMRI data. The pattern classification technique was used to verify the clinical application value of FC temporal variability. For the voxel-wise FC temporary variability, the repeated measures ANCOVA analysis showed significant treatment × time interaction effects on the FC temporary variability between the left DLPFC and several regions, including the thalamus, cerebellum, precuneus, and precentral gyrus, which are mainly located within the cortico-thalamo-cerebellar circuit (CTCC). For the ROI-wise FC temporary variability, our results found a significant interaction effect on the FC among CTCC. rTMS intervention led to a reduced FC temporary variability. In addition, higher alteration in FC temporal variability between left DLPFC and right posterior parietal thalamus predicted a higher remission ratio of negative symptom scores, indicating that the decrease of FC temporal variability between the brain regions was associated with the remission of schizophrenia severity. The support vector regression (SVR) results suggested that the baseline pattern of FC temporary variability between the regions in CTCC could predict the efficacy of high-frequency rTMS intervention on negative symptoms in schizophrenia. These findings confirm the potential relationship between the reduction in whole-brain functional dynamics induced by high-frequency rTMS and the improvement in psychiatric scores, suggesting that high-frequency rTMS affects psychiatric symptoms by coordinating the heterogeneity of activity between the brain regions. Future studies would examine the clinical utility of using functional dynamics patterns between specific brain regions as a biomarker to predict the treatment response of high-frequency rTMS.

Dopaminergic dysfunction and excitatory/inhibitory imbalance in treatment-resistant schizophrenia and novel neuromodulatory treatment

Antipsychotic drugs are the mainstay in the treatment of schizophrenia. However, one-third of patients do not show adequate improvement in positive symptoms with non-clozapine antipsychotics. Additionally, approximately half of them show poor response to clozapine, electroconvulsive therapy, or other augmentation strategies. However, the development of novel treatment for these conditions is difficult due to the complex and heterogenous pathophysiology of treatment-resistant schizophrenia (TRS). Therefore, this review provides key findings, potential treatments, and a roadmap for future research in this area. First, we review the neurobiological pathophysiology of TRS, particularly the dopaminergic, glutamatergic, and GABAergic pathways. Next, the limitations of existing and promising treatments are presented. Specifically, this article focuses on the therapeutic potential of neuromodulation, including electroconvulsive therapy, repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation. Finally, we propose multivariate analyses that integrate various perspectives of the pathogenesis, such as dopaminergic dysfunction and excitatory/inhibitory imbalance, thereby elucidating the heterogeneity of TRS that could not be obtained by conventional statistics. These analyses can in turn lead to a precision medicine approach with closed-loop neuromodulation targeting the detected pathophysiology of TRS.

Association between incarceration and psychotic experiences in a general population sample

Incarceration of individuals with mental disorders is an important public health topic. While incarceration appears to be associated with schizophrenia and related psychotic disorders, to the best of our knowledge, no study has examined the association between incarceration and psychotic experiences (PEs). The present study aimed to examine whether individuals with PEs had higher odds of incarceration among a general population sample using data from Baltimore and New York City (N = 974). We fitted three regression models to examine the association between incarceration and PEs, using hierarchical adjustments for sociodemographic factors, adverse childhood experiences, and neighborhood disruption. The odds ratio (OR) for incarceration was attenuated with inclusion of more covariates in the model but remained statistically significant even at the highest level of adjustment (OR = 2.12, 95% CI = 1.30 to 3.46). Findings were similar when individually examining delusional mood, delusions of reference and persecution, and hallucination. For delusions of control, a significant association was not found in the highest level of adjustment. The present study provides novel information on the association between incarceration and PEs, adjusted for sociodemographic and psychosocial confounders. Taken in the context of prior studies, these data further support the need to address the high prevalence of psychosis across all aspects of the criminal justice system. Future studies should employ longitudinal data and objective outcome measurements.

Effect of low-level laser therapy (LLLT) on cognitive impairment among patients with chronic schizophrenia: a double-blind randomized placebo-controlled clinical trial

Low-level laser therapy (LLLT) is a noninvasive technique used in different medical fields. It has been applied in different medical areas such as wound healing, traumatic brain injuries, neurological disorders, cognitive disorders, Alzheimer's disease, pain, and arthritis, with different results. We studied the effectiveness of LLLT on cognitive impairment in patients with chronic schizophrenia. A randomized controlled double-blind clinical trial was performed in a men's chronic treatment center, in Razi Psychiatric Hospital, in Tehran, Iran. We screened the cognitive impairment by Mini-Mental State Examination (MMSE). Positive And Negative Syndrome Scale (PANSS) was also used to assess the patients' positive and negative symptoms. Seventeen consenting patients were randomly allocated to the treatment arm, and 15 to the sham treatment control arm. The mean age of the control and treated patients was 49.47 ± 6.99 and 50.24 ± 7.69, respectively. No significant difference in PANSS and MMSE test scores was detected in both groups after the 6th session and after 2 months of follow-up after laser therapy. The positive and negative scales and agitation and excitement levels did not change significantly in either group. Nevertheless, the depression/anxiety subscale in the PANSS test showed a significant reduction after 6 sessions but did not persist after 2 months. No improvement in cognitive impairment or the positive and negative symptoms was detected after LLLT in patients with chronic schizophrenia. Trial registration: IRCT 20210520051349N1.

Low-frequency rTMS treatment alters the topographical organization of functional brain networks in schizophrenia patients with auditory verbal hallucination

Auditory verbal hallucinations (AVH) are an important characteristic of schizophrenia. Repeated transcranial magnetic stimulation (rTMS) has been evidence to be effective in treating AVH. We evaluated the topological properties of resting-state functional brain networks in schizophrenia patients with AVH (n = 32) who received 1-Hz rTMS treatment and matched healthy controls (n = 33). The results showed that the psychotic symptoms and certain neurocognitive performances in patients were improved by rTMS treatment. Furthermore, the pretreatment patients showed abnormal global topological metrics compared with the controls, including lower global efficiency (E_glob, represents the relative quality of information transmission between all nodes in the network) and higher characteristic path length (L_p, characterizes the mean shortest distance between any two nodes in the network). The pretreament patients also showed decreased local topological metrics relative to the controls, including the nodal shortest path (NL_p, quantifies the mean distance between the given node and the other nodes in the network) and nodal efficiency (N_e, measures the information interchange among the neighbor nodes when one node is removed), mainly located in the prefrontal cortex, occipital cortex, and subcortical regions. While the abnormal global and local topological patterns were normalized in patients after rTMS treatment. The multiple linear regression analysis indicated that the baseline topological metrics could be associated with the clinical responses after treatment in the patient group. The results suggested that the topological organization of the functional brain network was globally and regionally altered in schizophrenia patients with AVH after rTMS treatment and may be a potential therapeutic effect for AVH in schizophrenia.

European Psychiatric Association guidance on treatment of cognitive impairment in schizophrenia

Background

Although cognitive impairment is a core symptom of schizophrenia related to poorer outcomes in different functional domains, it still remains a major therapeutic challenge. To date, no comprehensive treatment guidelines for cognitive impairment in schizophrenia are implemented.

Methods

The aim of the present guidance paper is to provide a comprehensive meta-review of the current available evidence-based treatments for cognitive impairment in schizophrenia. The guidance is structured into three sections: pharmacological treatment, psychosocial interventions, and somatic treatments.

Results

Based on the reviewed evidence, this European Psychiatric Association guidance recommends an appropriate pharmacological management as a fundamental starting point in the treatment of cognitive impairment in schizophrenia. In particular, second-generation antipsychotics are recommended for their favorable cognitive profile compared to first-generation antipsychotics, although no clear superiority of a single second-generation antipsychotic has currently been found. Anticholinergic and benzodiazepine burdens should be kept to a minimum, considering the negative impact on cognitive functioning. Among psychosocial interventions, cognitive remediation and physical exercise are recommended for the treatment of cognitive impairment in schizophrenia. Noninvasive brain stimulation techniques could be taken into account as add-on therapy.

Conclusions

Overall, there is definitive progress in the field, but further research is needed to develop specific treatments for cognitive impairment in schizophrenia. The dissemination of this guidance paper may promote the development of shared guidelines concerning the treatment of cognitive functions in schizophrenia, with the purpose to improve the quality of care and to achieve recovery in this population.

Adjunctive multi-session transcranial direct current stimulation for neurocognitive dysfunction in schizophrenia: A meta-analysis

Findings of multi-session transcranial direct current stimulation (tDCS) as an adjunctive treatment of neurocognitive dysfunction in schizophrenia have been inconsistent. This meta-analysis of randomized controlled trials (RCTs) investigated the neurocognitive effects of adjunctive multi-session tDCS for schizophrenia. Twelve RCTs covering 418 schizophrenia patients were included and analyzed in this meta-analysis. The RevMan software (Version 5.3) was used to calculate risk ratios (RRs) and standardized mean differences (SMDs) with their 95% confidence intervals (CIs). Adjunctive tDCS outperformed the comparator in improving working memory deficits (SMD = 0.34, 95% CI: 0.03, 0.65; I² = 52%; p = 0.03), but no significant effects were found in other cognitive domains. No group differences were found with regard to total psychopathology measured by the Brief Psychiatric Rating Scale and the Positive and Negative Symptom Scale (SMD =-0.29, 95%CI: -0.61, 0.03; I² = 50%, p = 0.07) and discontinuation due to any reason (RR=0.80, 95%CI: 0.39, 1.66; I² = 9%, p = 0.56). Adjunctive tDCS appears to have a significant therapeutic effect improving the working memory deficits in schizophrenia.

rTMS Induces Brain Functional and Structural Alternations in Schizophrenia Patient With Auditory Verbal Hallucination

BACKGROUND

Low-frequency transcranial magnetic stimulation (rTMS) over the left temporoparietal cortex reduces the auditory verbal hallucination (AVH) in schizophrenia. However, the underlying neural basis of the rTMS treatment effect for schizophrenia remains not well understood. This study investigates the rTMS induced brain functional and structural alternations and their associations with clinical as well as neurocognitive profiles in schizophrenia patients with AVH.

METHODS

Thirty schizophrenia patients with AVH and thirty-three matched healthy controls were enrolled. The patients were administered by 15 days of 1 Hz rTMS delivering to the left temporoparietal junction (TPJ) area. Clinical symptoms and neurocognitive measurements were assessed at pre- and post-rTMS treatment. The functional (amplitude of low-frequency fluctuation, ALFF) and structural (gray matter volume, GMV) alternations were compared, and they were then used to related to the clinical and neurocognitive measurements after rTMS treatment.

RESULTS

The results showed that the positive symptoms, including AVH, were relieved, and certain neurocognitive measurements, including visual learning (VisLearn) and verbal learning (VerbLearn), were improved after the rTMS treatment in the patient group. Furthermore, the rTMS treatment induced brain functional and structural alternations in patients, such as enhanced ALFF in the left superior frontal gyrus and larger GMV in the right inferior temporal cortex. The baseline ALFF and GMV values in certain brain areas (e.g., the inferior parietal lobule and superior temporal gyrus) could be associated with the clinical symptoms (e.g., positive symptoms) and neurocognitive performances (e.g., VerbLearn and VisLearn) after rTMS treatment in patients.

CONCLUSION

The low-frequency rTMS over the left TPJ area is an efficacious treatment for schizophrenia patients with AVH and could selectively modulate the neural basis underlying psychiatric symptoms and neurocognitive domains in schizophrenia.

Recent Advances and Future Directions in Brain MR Imaging Studies in Schizophrenia: Toward Elucidating Brain Pathology and Developing Clinical Tools

Schizophrenia is a common severe psychiatric disorder that affects approximately 1% of general population through the life course. Historically, in Kraepelin's time, schizophrenia was a disease unit conceptualized as dementia praecox; however, since then, the disease concept has changed. Recent MRI studies had shown that the neuropathology of the brain in this disorder was characterized by mild progression before and after the onset of the disease, and that the brain alterations were relatively smaller than assumed. Although genetic factors contribute to the brain alterations in schizophrenia, which are thought to be trait differences, other changes include factors that are common in psychiatric diseases. Furthermore, it has been shown that the brain differences specific to schizophrenia were relatively small compared to other changes, such as those caused by brain development, aging, and gender. In addition, compared to the disease and participant factors, machine and imaging protocol differences could affect MRI signals, which should be addressed in multi-site studies. Recent advances in MRI modalities, such as multi-shell diffusion-weighted imaging, magnetic resonance spectroscopy, and multimodal brain imaging analysis, may be candidates to sharpen the characterization of schizophrenia-specific factors and provide new insights. The Brain/MINDS Beyond Human Brain MRI (BMB-HBM) project has been launched considering the differences and noises irrespective of the disease pathologies and includes the future perspectives of MRI studies for various psychiatric and neurological disorders. The sites use restricted MRI machines and harmonized multi-modal protocols, standardized image preprocessing, and traveling subject harmonization. Data sharing to the public will be planned in FY 2024. In the future, we believe that combining a high-quality human MRI dataset with genetic data, randomized controlled trials, and MRI for non-human primates and animal models will enable us to understand schizophrenia, elucidate its neural bases and therapeutic targets, and provide tools for clinical application at bedside.

The Effects of Repetitive Transcranial Magnetic Stimulation on Cognitive Impairment and the Brain Lipidome in a Cuprizone-Induced Mouse Model of Demyelination

The protective effects of repetitive transcranial magnetic stimulation (rTMS) on myelin integrity have been extensively studied, and growing evidence suggests that rTMS is beneficial in improving cognitive functions and promoting myelin repair. However, the association between cognitive improvement due to rTMS and changes in brain lipids remains elusive. In this study, we used the Y-maze and 3-chamber tests, as well as a mass spectrometry-based lipidomic approach in a CPZ-induced demyelination model in mice to assess the protective effects of rTMS on cuprizone (CPZ)-induced cognitive impairment and evaluate changes in lipid composition in the hippocampus, prefrontal cortex, and striatum. We found that CPZ induced cognitive impairment and remarkable changes in brain lipids, specifically in glycerophospholipids. Moreover, the changes in lipids within the prefrontal cortex were more extensive, compared to those observed in the hippocampus and striatum. Notably, rTMS ameliorated CPZ-induced cognitive impairment and partially normalized CPZ-induced lipid changes. Taken together, our data suggest that rTMS may reverse cognitive behavioral changes caused by CPZ-induced demyelination by modulating the brain lipidome, providing new insights into the therapeutic mechanism of rTMS.

Investigating neurophysiological markers of impaired cognition in schizophrenia

Cognitive impairment is highly prevalent in schizophrenia and treatment options are severely limited. A greater understanding of the pathophysiology of impaired cognition would have broad implications, including for the development of effective treatments. In the current study we used a multimodal approach to identify neurophysiological markers of cognitive impairment in schizophrenia. Fifty-seven participants (30 schizophrenia, 27 controls) underwent neurobiological assessment (electroencephalography [EEG] and Transcranial Magnetic Stimulation combined with EEG [TMS-EEG]) and assessment of cognitive functioning using an n-back task and the MATRICS Consensus Cognitive Battery. Neurobiological outcome measures included oscillatory power during a 2-back task, TMS-related oscillations and TMS-evoked potentials (TEPs). Cognitive outcome measures were d prime and accurate reaction time on the 2-back and MATRICS domain scores. Compared to healthy controls, participants with schizophrenia showed significantly reduced theta oscillations in response to TMS, and trend level decreases in task-related theta and cortical reactivity (i.e. reduced N100 and N40 TEPs). Participants with schizophrenia also showed significantly impaired cognitive performance across all measures. Correlational analysis identified significant associations between cortical reactivity and TMS-related oscillations in both groups; and trend level associations between task-related oscillations and impaired cognition in schizophrenia. The current study provides experimental support for possible neurophysiological markers of cognitive impairment in schizophrenia. The potential implications of these findings, including for treatment development, are discussed.

Examining and Modulating Neural Circuits in Psychiatric Disorders With Transcranial Magnetic Stimulation and Electroencephalography: Present Practices and Future Developments

Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique uniquely equipped to both examine and modulate neural systems and related cognitive and behavioral functions in humans. As an examination tool, TMS can be used in combination with EEG (TMS-EEG) to elucidate directly, objectively, and noninvasively the intrinsic properties of a specific cortical region, including excitation, inhibition, reactivity, and oscillatory activity, irrespective of the individual's conscious effort. Additionally, when applied in repetitive patterns, TMS has been shown to modulate brain networks in healthy individuals, as well as ameliorate symptoms in individuals with psychiatric disorders. The key role of TMS in assessing and modulating neural dysfunctions and associated clinical and cognitive deficits in psychiatric populations is therefore becoming increasingly evident. In this article, the authors review TMS-EEG studies in schizophrenia and mood disorders, as most TMS-EEG studies to date have focused on individuals with these disorders. The authors present the evidence on the efficacy of repetitive TMS (rTMS) and theta burst stimulation (TBS), when targeting specific cortical areas, in modulating neural circuits and ameliorating symptoms and abnormal behaviors in individuals with psychiatric disorders, especially when informed by resting-state and task-related neuroimaging measures. Examples of how the combination of TMS-EEG assessments and rTMS and TBS paradigms can be utilized to both characterize and modulate neural circuit alterations in individuals with psychiatric disorders are also provided. This approach, along with the evaluation of the behavioral effects of TMS-related neuromodulation, has the potential to lead to the development of more effective and personalized interventions for individuals with psychiatric disorders.

Repetitive Transcranial Magnetic Stimulation as a Therapeutic and Probe in Schizophrenia: Examining the Role of Neuroimaging and Future Directions

Schizophrenia is a complex condition associated with perceptual disturbances, decreased motivation and affect, and disrupted cognition. Individuals living with schizophrenia may experience myriad poor outcomes, including impairment in independent living and function as well as decreased life expectancy. Though existing treatments may offer benefit, many individuals still experience treatment resistant and disabling symptoms. In light of the negative outcomes associated with schizophrenia and the limitations in currently available treatments, there is a significant need for novel therapeutic interventions. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique that can modulate the activity of discrete cortical regions, allowing direct manipulation of local brain activation and indirect manipulation of the target's associated neural networks. rTMS has been studied in schizophrenia for the treatment of auditory hallucinations, negative symptoms, and cognitive deficits, with mixed results. The field's inability to arrive at a consensus on the use rTMS in schizophrenia has stemmed from a variety of issues, perhaps most notably the significant heterogeneity amongst existing trials. In addition, it is likely that factors specific to schizophrenia, rather than the rTMS itself, have presented barriers to the interpretation of existing results. However, advances in approaches to rTMS as a biologic probe and therapeutic, many of which include the integration of neuroimaging with rTMS, offer hope that this technology may still play a role in improving the understanding and treatment of schizophrenia.

Cortical plasticity is correlated with cognitive improvement in Alzheimer's disease patients after rTMS treatment

OBJECTIVE

Repetitive transcranial magnetic stimulation (rTMS) has been widely used in non-invasive treatments for different neurological disorders. Few biomarkers are available for treatment response prediction. This study aims to analyze the correlation between changes in long-term potentiation (LTP)-like cortical plasticity and cognitive function in patients with Alzheimer's disease (AD) that underwent rTMS treatment.

METHODS

A total of 75 AD patients were randomized into either 20 Hz rTMS treatment at the dorsolateral prefrontal cortex (DLPFC) group (n = 37) or a sham treatment group (n = 38) for 30 sessions over six weeks (five days per week) with a three-month follow-up. Neuropsychological assessments were conducted using the Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment-Cognitive Component (ADAS-Cog). The cortical plasticity reflected by the motor-evoked potential (MEP) before and after high-frequency repetitive TMS to the primary motor cortex (M1) was also examined prior to and after the treatment period.

RESULTS

The results showed that the cognitive ability of patients who underwent the MMSE and ADAS-Cog assessments showed small but significant improvement after six weeks of rTMS treatment compared with the sham group. The cortical plasticity improvement correlated to the observed cognition change.

CONCLUSIONS

Cortical LTP-like plasticity could predict the treatment responses of cognitive improvements in AD patients receiving rTMS intervention. This warrants future clinical trials using cortical LTP as a predictive marker.

Effects of High-Frequency rTMS on Negative Symptoms and Cognitive Function in Hospitalized Patients With Chronic Schizophrenia: A Double-Blind, Sham-Controlled Pilot Trial

This study aimed to evaluate the efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) over left dorsolateral pre-frontal cortex (DLPFC) in ameliorating negative symptoms and cognitive impairments in patients with chronic schizophrenia. Fifty-two patients with chronic schizophrenia were randomly assigned to two groups: active rTMS group and sham rTMS group, with existing antipsychotic drugs combined 20 sessions of 10 Hz active/sham rTMS over DLPFC (20 min/session, 5 times/week). The PANSS, RBANS, and SCWT were used to evaluate the clinical symptoms and cognitive functions of the patients. Our results indicated significant improvements in clinical symptoms (PANSS total and subscale scores) and cognitive functions (RBANS total and subscale scores, card 1 and card 3 of the SCWT test) (All p <0.05) after 4-week intervention both in active and sham rTMS group. Moreover, the active rTMS group showed more effective on ameliorating negative symptoms (p = 0.002), immediate memory (p = 0.016) and delayed memory (p = 0.047) compared to the sham group. Interestingly, PANSS negative symptom scores was negatively correlated with RBANS language scores in the real stimulation group (p = 0.046). The study found that the high frequency rTMS stimulation over left DLPFC as a supplement to antipsychotics may have potential benefits in improving clinical symptoms and cognitive functions in patients with chronic schizophrenia.

Functional MRI in the effect of transcranial magnetic stimulation therapy for patients with schizophrenia: a meta-analysis protocol

INTRODUCTION

Schizophrenia is a psychiatric illness associated with brain function alterations and varying degree of treatment resistance, often leading to severe social malfunctioning. In recent decades, numerous studies have been investigating the therapeutic potential of transcranial magnetic stimulation (TMS) as a non-invasive therapy for schizophrenia. However, its clinical efficacy remains controversial, as a number of clinical trials indicated moderate therapeutic effect while others failed to reproduce the positive result. Moreover, the neurobiological mechanism of action remains unclear, possibly constricting the application of TMS in clinical practice. The present protocol of meta-analysis aims to investigate the TMS-related functional neuroimaging (ie, functional MRI) features and alterations in subjects with schizophrenia, and to discuss the potential of functional MRI in TMS researches.

METHODS AND ANALYSIS

The study selection process will follow the Preferred Reporting Items for Meta-Analyses guideline and quality assessment will be conducted with a customised checklist. We plan to search in the following databases: PubMed, Embase, OVID, China National Knowledge Infrastructure and Wanfang Data, from their respective dates of inception to 1 May 2020, with language restricted to English and Chinese. Studies focusing on the brain functional alterations in patients with schizophrenia treated by TMS will be retrieved.

ETHICS AND DISSEMINATION

This work does not require ethics approval as it will be based on published studies. This systematic review will be publicly disseminated in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42020166288.

Effects of Repetitive Transcranial Magnetic Stimulation on Working Memory Performance and Brain Structure in People With Schizophrenia Spectrum Disorders: A Double-Blind, Randomized, Sham-Controlled Trial

BACKGROUND

There are currently no approved treatments for working memory deficits in schizophrenia spectrum disorders (SSDs). The objective of the present study was to assess whether repetitive transcranial magnetic stimulation (rTMS) to the bilateral dorsolateral prefrontal cortex (DLPFC) in people with SSDs 1) improves working memory deficits and 2) changes brain structure.

METHODS

We conducted a double-blind, parallel, randomized, sham-controlled study at the Centre for Addiction and Mental Health in Toronto, Canada. We randomized 83 participants with SSDs to receive either active 20 Hz rTMS applied to the bilateral DLPFC or sham rTMS for 4 weeks. The participants also completed pre/posttreatment magnetic resonance imaging. Clinical and cognitive assessments were performed at baseline, treatment end, and 1 month later. The primary outcome was change in verbal n-back working memory performance accuracy (d-prime). The secondary outcome measures were change in DLPFC thickness and fractional anisotropy of white matter tracts connecting to the DLPFC. Prespecified exploratory outcome measures were changes in general cognition; positive, negative, and depressive symptoms.

RESULTS

Compared with sham treatment, active rTMS did not lead to significant change in working memory performance; it was associated with an increase in right DLPFC thickness but not fractional anisotropy. Prespecified exploratory analysis showed a significant decrease in depressive symptoms in the active group; the decrease in depressive symptoms was correlated with an increase in right DLPFC thickness.

CONCLUSIONS

Although rTMS applied to the bilateral DLPFC was not efficacious in treating working memory deficits in SSDs, it did increase right DLPFC thickness and decrease depressive symptoms. These findings deserve further study given the lack of efficacy of antidepressant medications in SSDs.

Non-Invasive Brain Stimulation Does Not Improve Working Memory in Schizophrenia: A Meta-Analysis of Randomised Controlled Trials

Poor working memory functioning is commonly found in schizophrenia. A number of studies have now tested whether non-invasive brain stimulation can improve this aspect of cognitive functioning. This report used meta-analysis to synthesise the results of these studies to examine whether transcranial electrical stimulation (tES) or repetitive transcranial magnetic stimulation (rTMS) can improve working memory in schizophrenia. The studies included in this meta-analysis were sham-controlled, randomised controlled trials that utilised either tES or rTMS to treat working memory problems in schizophrenia. A total of 22 studies were included in the review. Nine studies administered rTMS and 13 administered tES. Meta-analysis revealed that compared to sham/placebo stimulation, neither TMS nor tES significantly improved working memory. This was found when working memory was measured with respect to the accuracy on working memory tasks (TMS studies: Hedges' g = 0.112, CI₉₅: -0.082, 0.305, p = .257; tES studies Hedges' g = 0.080, CI₉₅: -0.117, 0.277, p = .427) or the speed working memory tasks were completed (rTMS studies: Hedges' g = 0.233, CI₉₅: -0.212, 0.678, p = .305; tES studies Hedges' g = -0.016, CI₉₅: -0.204, 0.173, p = .871). For tES studies, meta-regression analysis found that studies with a larger number of stimulation sessions were associated with larger treatment effects. This association was not found for TMS studies. At present, rTMS and tES is not associated with a reliable improvement in working memory for individuals with schizophrenia.

The effect of bilateral high frequency repetitive transcranial magnetic stimulation on cognitive functions in schizophrenia

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Despite their major effects on positive symptoms, antipsychotics do not have a significant effect on cognition in schizophrenia

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Bilateral high frequency rTMS targeting dorsolateral prefrontal cortices has been effective on working memory

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Bilateral 20 Hz rTMS improved attention and verbal working memory in schizophrenia patients,

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It also improved the competence of switching the perceptional set up under a disruptive effect towards new instructions, in this study

Baduanjin mind-body exercise improves logical memory in long-term hospitalized patients with schizophrenia: A randomized controlled trial

Neurocognitive impairment is one of the core symptoms in schizophrenia and poses a great challenge to effective treatment. Sixty-one long-term hospitalized patients with schizophrenia were recruited and randomly assigned to two groups: Baduanjin exercise and brisk walking. Patients in the Baduanjin group received 24 weeks of Baduanjin training (5 days/week, 40 min/day), while patients in the brisk walking group received 24 weeks of brisk walking (5 days/week, 40 min/day). Scores on the Wechsler Memory Scale, Digit Symbol Substitution Test (DSST), and the positive and negative syndrome scale were used to evaluate the logical memory (LM), processing speed, and clinical symptoms of all participants, while the score of Trail Making Test-A (TMT-A) was applied to assess the visual attention and graphomotor speed, at baseline and the 16th week and 24th week of intervention. The one-way repeated measures analysis of variance (ANOVA) was used to test the differences in neurocognitive changes between the two groups. Repeated measures ANOVA showed significant differences between the two groups in the LM immediate (F = 6.21, p = 0.003) and LM delayed (F=5.60, p = 0.005) scores, but not in the completion times of TMT-A (F=.22, p = 0.806) or DSST scores (F=0.97, p = 0.328). A significant effect of time was also detected in the LM immediate (F=10.24, p = 0.000) and LM delayed (F=4.93, p = 0.009) scores and in the completion time of the TMT-A (F=33.10, p = 0.000), but not in the DSST scores (F=2.12, p = 0.122). Baduanjin exercise could improve logical memory in the long-term hospitalized patients with schizophrenia.

Cerebral cortex activation during the Sternberg verbal working memory task

Despite intensive study, the data regarding functional role of specific brain regions in the working memory processes still remain controversial. The study was aimed to determine the activation of cerebral cortex regions at different stages of the working memory task (information encoding, maintenance and retrieval). Functional magnetic resonance imaging (fMRI) with the modified Sternberg task was applied to 19 healthy volunteers. The objective of the task was to memorize and retain in memory the sequence of 7 letters with the subsequent comparison of one letter with the sequence. Activation was analyzed during three periods of the task compared to the rest period, as well as temporal dynamics of changes in BOLD signal intensity in three regions: left dorsolateral prefrontal, left posterior parietal and left occipital cortex. According to the results, significant activation of the regions in prefrontal and posterior parietal cortex was observed during all periods of the task (p < 0.05), but there were changes in its localization and lateralization. The activation pattern during the maintenance period corresponded to the fronto-parietal control network components. According to the analysis of temporal dynamics of changes in BOLD signal intensity, the most prominent activation of the dorsolateral prefrontal cortex and parietal cortex was observed in the end of the encoding period, during the maintenance period and in the beginning of the retrieval period, which confirmed the role of those areas in the working memory processes. The maximum of occipital cortex activation was observed during encoding period. The study confirmed the functional role of the dorsolateral prefrontal cortex and posterior parietal cortex in the working memory mechanisms during all stages of the Sternberg task.

Effect of multi-session prefrontal transcranial direct current stimulation on cognition in schizophrenia: A systematic review and meta-analysis

Patients with schizophrenia experience cognitive deficits that play a central role in predicting functional outcomes. In this study, we sought to evaluate the effect of transcranial direct current stimulation (tDCS) on cognition using meta-analysis. A search was performed from inception to 8 January 2019, to identify randomized controlled trials assessing the ability of tDCS to ameliorate cognitive deficits in patients with schizophrenia and schizoaffective disorder. The effect size, calculated as the standardized mean difference (Hedge's g), was obtained with a random effect model. We analyzed mean effects on specific cognitive domains that were evaluated in four or more studies. Nine articles were included in the systematic review, which encompassed 270 patients: 133 in the active stimulation group and 137 in the sham stimulation group. Meta-analysis demonstrated a significant mean effect of tDCS on working memory (SMD = 0.49, 95% CI = 0.16 to 0.83), while non-significant results were produced for other domains. These findings were supported by sensitivity analyses indicating that the results would not change in a meaningful way after the exclusion of each single study, and meta-regression analyses verifying the consistent effect irrespective of any moderators. Thus, tDCS may provide a potential option to improve working memory deficits in individuals with schizophrenia. Further trials examining the cognitive benefit of tDCS with medication or other adjunctive treatments are warranted.

High-Frequency Repetitive Transcranial Magnetic Stimulation Could Improve Impaired Working Memory Induced by Sleep Deprivation

Objective

To investigate whether and how the working memory impairment induced by sleep deprivation (SD) could be recovered by using repetitive transcranial magnetic stimulation (rTMS), as well as to clarify the corresponding brain activity changes.

Methods

Seventeen healthy adults received one session of 5.0 Hz rTMS over the left dorsolateral prefrontal cortex (DLPFC) following 24 hours of SD. Resting state functional magnetic resonance imaging (fMRI) and working memory test were performed during a rested waking period, after SD and rTMS. The amplitude of low-frequency fluctuations (ALFF) was used to detect the spontaneous neural activity changes after both SD and rTMS. The relationship between ALFF and the performance of working memory was also assessed by using correlation analysis.

Results

After SD, the participants exhibited lower response accuracies and longer reaction times on the working memory tests of letters and numbers. The decreased response accuracy of numbers was significantly improved after rTMS similarly to the state of the rested waking period after a normal night of sleep. ALFF values decreased from the rested waking period state to the state of SD in the brain regions involving the frontal gyrus, precuneus, angular gyrus, and parietal lobe which showed significantly increased ALFF after rTMS. Furthermore, significantly positive correlations were observed between changes of response accuracy and the changes of ALFF value of the inferior frontal gyrus and supramarginal gyrus.

Conclusion

These results indicate that high-frequency rTMS applied over left DLPFC may contribute to the recovery of the impaired working memory after SD by modulating the neural activity of related brain regions.

A pilot investigation of an intensive theta burst stimulation protocol for patients with treatment resistant depression

INTRODUCTION

Accelerated or intensive forms of repetitive transcranial magnetic stimulation (rTMS) are increasingly being explored for their potential to produce more efficient and rapid treatment benefits in major depressive disorder (MDD). However, accelerated or intensive protocols using standard forms of rTMS are still quite time-consuming to apply. Theta burst stimulation (TBS) is a novel form of magnetic stimulation with the potential to produce similar anti-depressant effects but in a much abbreviated period of time. The aim of this study was to investigate the comparative efficacy of an intensive TBS protocol compared to standard rTMS treatment.

METHODS

74 outpatients (36 female, mean age 44.36 ± 12.1 years) with MDD received either intensive TBS (3 intermittent TBS treatments per day for 3 days in week 1, 3 treatments a day for 2 days in week 2, and 3 treatments in 1 day in week 3 and in week 4, or standard rTMS (5 daily sessions per week for 4 weeks). Patients were assessed weekly throughout the treatment course, and at 4 weeks after treatment end.

RESULTS

There were no significant differences in the degree of reduction in depressive symptoms, the rate of reduction in depressive symptoms, remission or response rates (response rates = 27.8% for intensive group, 26.3% for the standard group, p > 0.05 for all analyses) between the intensive TBS and standard rTMS treatment groups. However, the overall response and remission rates were limited in both groups. There was no difference in rates of side effects, no serious adverse events and no alterations in cognitive performance.

CONCLUSION

Intensively applied TBS appears to have similar efficacy to standard rTMS when these were applied as delivered in this study but does not produce more rapid clinical benefits. The overall response rates in both groups in this study were limited, most likely by the total doses provided in both study arms.

CLINICAL TRIALS REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12616000443493.

Investigational and Therapeutic Applications of Transcranial Magnetic Stimulation in Schizophrenia

PURPOSE OF REVIEW

This current review summarizes the investigational and therapeutic applications of transcranial magnetic stimulation (TMS) in schizophrenia.

RECENT FINDINGS

Fairly consistent findings of an impaired cortical excitation-inhibition balance, cortical plasticity, and motor resonance have been reported in schizophrenia. Cortical connectivity impairments have also been demonstrated in motor and prefrontal brain regions. In terms of treatment, the best support is for 1-Hz TMS to the left temporoparietal cortex for the short-term treatment of persistent auditory hallucinations. High-frequency TMS to the left prefrontal cortex improves negative and cognitive symptoms, but with inconsistent and small effects. TMS combined with diverse brain mapping techniques and clinical evaluation can unravel critical brain-behavior relationships relevant to schizophrenia. These provide critical support to the conceptualization of schizophrenia as a connectopathy with anomalous cortical plasticity. Adaptive modulation of these aberrant brain networks in a neuroscience-informed manner drives short-term therapeutic gains in difficult-to-treat symptoms of schizophrenia.