What is the potential of neurostimulation in the treatment of motor symptoms in schizophrenia?

Isolation of Distinct Networks Driving Action and Cognition in Psychomotor Processes

BACKGROUND

Psychomotor disturbances are observed across psychiatric disorders and often manifest as psychomotor slowing, agitation, disorganized behavior, or catatonia. Psychomotor function includes both cognitive and motor components, but the neural circuits driving these subprocesses and how they relate to symptoms have remained elusive for centuries.

METHODS

We analyzed data from the HCP-EP (Human Connectome Project for Early Psychosis), a multisite study of 125 participants with early psychosis and 58 healthy participants with resting-state functional magnetic resonance imaging and clinical characterization. Psychomotor function was assessed using the 9-hole pegboard task, a timed motor task that engages mechanical and psychomotor components of action, and tasks assessing processing speed and task switching. We used multivariate pattern analysis of whole-connectome data to identify brain correlates of psychomotor function.

RESULTS

We identified discrete brain circuits driving the cognitive and motor components of psychomotor function. In our combined sample of participants with psychosis (n = 89) and healthy control participants (n = 52), the strongest correlates of psychomotor function (pegboard performance) (p < .005) were between a midline cerebellar region and left frontal region and presupplementary motor area. Psychomotor function was correlated with both cerebellar-frontal connectivity (r = 0.33) and cerebellar-presupplementary motor area connectivity (r = 0.27). However, the cognitive component of psychomotor performance (task switching) was correlated only with cerebellar-frontal connectivity (r = 0.19), whereas the motor component (processing speed) was correlated only with cerebellar-presupplementary motor area connectivity (r = 0.15), suggesting distinct circuits driving unique subprocesses of psychomotor function.

CONCLUSIONS

We identified cerebellar-cortical circuits that drive distinct subprocesses of psychomotor function. Future studies should probe relationships between cerebellar connectivity and psychomotor performance using neuromodulation.

Test-retest reliability of resting-state cerebral blood flow quantification using pulsed Arterial Spin Labeling (PASL) over 3 weeks vs 8 weeks in healthy controls

Arterial Spin Labeling is a valuable functional imaging tool for both clinical and research purposes. However, little is known about the test-retest reliability of cerebral blood flow measurements over longer periods. In this study, we investigated the reliability of pulsed Arterial Spin Labeling in assessing cerebral blood flow over a 3 (n = 28) vs 8 (n = 19) weeks interscan interval in 47 healthy participants. As a measure of cerebral blood flow reliability, we calculated voxel-wise, whole-brain, and regions of interest intraclass correlation coefficients. The whole-brain mean resting-state cerebral blood flow showed good to excellent reliability over time for both periods (intraclass correlation coefficients = 0.85 for the 3-week delay, intraclass correlation coefficients = 0.53 for the 8-week delay). However, the voxel-wise and regions of interest intraclass correlation coefficients fluctuated at 8-week compared to the 3-week interval, especially within cortical areas. These results confirmed previous findings that Arterial Spin Labeling could be used as a reliable method to assess brain perfusion. However, as the reliability seemed to decrease over time, caution is warranted when performing correlations with other variables, especially in clinical populations.

Psychomotor Slowing in Psychosis and Inhibitory Repetitive Transcranial Magnetic Stimulation: A Randomized Clinical Trial

Importance

Psychomotor slowing is a frequent symptom of psychosis, impairing gross and fine motor behavior. It is associated with poor outcomes and functioning, and no treatment is available.

Objective

To investigate whether 15 sessions of inhibitory repetitive transcranial magnetic stimulation (rTMS) may reduce psychomotor slowing.

Design, Setting, and Participants

This was a 4-arm, double-blind, randomized, sham-controlled trial at a university hospital in Switzerland. Enrollment took place from March 2019 to August 2022. Adults aged 18 to 60 years with schizophrenia spectrum disorders and severe psychomotor slowing were eligible. All patients continued existing medications, including antipsychotics and benzodiazepines. Those with substance misuse (other than nicotine), conditions associated with impaired or aberrant movement, convulsions, history of hearing problems, other conditions typically excluded from magnetic resonance imaging or TMS, any TMS treatment in the past 3 months, or those who were pregnant or breastfeeding were excluded. Of 615 patients screened for eligibility, 103 were randomized and 88 received at least 1 session of rTMS: 22 were assigned to 1-Hz rTMS, 22 to iTBS, 22 to sham, and 22 to the waiting group. Follow-up was conducted at 6 weeks and 24 weeks following the week 3 assessments including clinical, functional, and motor measures.

Interventions

Fifteen sessions of rTMS in 3 weeks over the supplementary motor area: 1-Hz rTMS, iTBS, sham, or no treatment (waiting). After 3 weeks, the waiting group received 15 sessions of 1-Hz rTMS over the supplementary motor area.

Main Outcomes and Measures

The main outcome was the proportion of responders at week 3 in the Salpêtrière Retardation Rating Scale (SRRS) defined as a 30% or greater reduction from baseline (last-observation-carried-forward). The SRRS has 15 items and a maximum total score of 60.

Results

Of the 88 participants analyzed, 45 were men and 43 were women. The mean (SD) age was 36.3 (12.4) years and the mean (SD) SRRS score was 24.0 (5.9). A total of 69 participants completed the study. At week 3, response rates differed between groups: 15 of 22 (68%) in the 1-Hz rTMS group, 8 of 22 (36%) in the iTBS group, 7 of 22 (32%) in the sham group, and 4 of 22 (18%) in the waiting group (χ23 = 12.1; P = .007). The 1-Hz rTMS group had more responders than sham (odds ratio [OR], 0.13; 95% CI, 0.02-0.65; P = .03), iTBS (OR, 0.12; 95% CI, 0.02-0.61; P = .02), and waiting (OR, 0.04; 95% CI, 0.01-0.22; P = .003). In the waiting group, 10 of 16 participants (63%) responded after receiving 15 sessions of 1-Hz rTMS. No serious adverse events occurred.

Conclusions and Relevance

In this study, inhibitory add-on rTMS safely alleviated psychomotor slowing in psychosis compared with iTBS, sham, and no treatment. The treatment was also effective with delayed onset. Future studies need to explore the neural changes associated with supplementary motor area rTMS in psychosis.

Trial Registration

ClinicalTrials.gov Identifier: NCT03921450.

In Silico Discovery of Potential Inhibitors Targeting the RNA Binding Loop of ADAR2 and 5-HT2CR from Traditional Chinese Natural Compounds

Adenosine deaminase acting on RNA 2 (ADAR2) is an important enzyme involved in RNA editing processes, particularly in the conversion of adenosine to inosine in RNA molecules. Dysregulation of ADAR2 activity has been implicated in various diseases, including neurological disorders (including schizophrenia), inflammatory disorders, viral infections, and cancers. Therefore, targeting ADAR2 with small molecules presents a promising therapeutic strategy for modulating RNA editing and potentially treating associated pathologies. However, there are limited compounds that effectively inhibit ADAR2 reactions. This study therefore employed computational approaches to virtually screen natural compounds from the traditional Chinese medicine (TCM) library. The shortlisted compounds demonstrated a stronger binding affinity to the ADAR2 (<-9.5 kcal/mol) than the known inhibitor, 8-azanebularine (-6.8 kcal/mol). The topmost compounds were also observed to possess high binding affinity towards 5-HT2CR with binding energies ranging from -7.8 to -12.9 kcal/mol. Further subjecting the top ADAR2-ligand complexes to molecular dynamics simulations and molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) calculations revealed that five potential hit compounds comprising ZINC000014637370, ZINC000085593577, ZINC000042890265, ZINC000039183320, and ZINC000101100339 had favorable binding free energies of -174.911, -137.369, -117.236, -67.023, and -64.913 kJ/mol, respectively, with the human ADAR2 protein. Residues Lys350, Cys377, Glu396, Cys451, Arg455, Ser486, Gln488, and Arg510 were also predicted to be crucial in ligand recognition and binding. This finding will provide valuable insights into the molecular interactions between ADAR2 and small molecules, aiding in the design of future ADAR2 inhibitors with potential therapeutic applications. The potential lead compounds were also profiled to have insignificant toxicities. A structural similarity search via DrugBank revealed that ZINC000039183320 and ZINC000014637370 were similar to naringin and naringenin, which are known adenosine deaminase (ADA) inhibitors. These potential novel ADAR2 inhibitors identified herein may be beneficial in treating several neurological disorders, cancers, viral infections, and inflammatory disorders caused by ADAR2 after experimental validation.

Short- and long-term changes in symptom dimensions among patients with schizophrenia spectrum disorders and different durations of illness: A meta-analysis

In schizophrenia spectrum disorders, improvement in symptoms varies between patients with short and long durations of illness. In this meta-analysis we provided an overview of both short- and long-term symptomatic improvement for patients with schizophrenia spectrum disorders with distinct durations of illness. We included 82 longitudinal studies assessing the course of positive, negative, depressive and disorganization symptoms. We analyzed effect sizes of change in four subgroups based on durations of illness at baseline: <2 years, 2-5 years, 5-10 years, >10 years. Potential moderators were explored using meta-regression and sensitivity analyses. Overall, we found large improvements of positive symptoms and small improvements of negative, depressive, and disorganization symptoms. Positive and disorganization symptoms improved relatively stronger for patients earlier in the course of illness, whereas negative and depressive symptoms showed modest improvement regardless of duration of illness. Improvement of symptoms was associated with higher baseline severity of positive symptoms, a younger age, a smaller subsample with schizophrenia, and, specifically for negative symptoms, higher baseline severity of depressive symptoms. Future research should focus on exploring ways to optimize improvement in negative and depressive symptoms for patients with schizophrenia spectrum disorders.

Molecular Docking and Dynamics Simulation Studies Predict Potential Anti-ADAR2 Inhibitors: Implications for the Treatment of Cancer, Neurological, Immunological and Infectious Diseases

Altered RNA editing has been linked to several neurodevelopmental disorders, including autism spectrum disorder (ASD) and intellectual disability, in addition to depression, schizophrenia, some cancers, viral infections and autoimmune disorders. The human ADAR2 is a potential therapeutic target for managing these various disorders due to its crucial role in adenosine to inosine editing. This study applied consensus scoring to rank potential ADAR2 inhibitors after performing molecular docking with AutoDock Vina and Glide (Maestro), using a library of 35,161 compounds obtained from traditional Chinese medicine. A total of 47 compounds were predicted to be good binders of the human ADAR2 and had insignificant toxicity concerns. Molecular dynamics (MD) simulations, including the molecular mechanics Poisson–Boltzmann surface area (MM/PBSA) procedure, also emphasized the binding of the shortlisted compounds. The potential compounds had plausible binding free energies ranging from −81.304 to −1068.26 kJ/mol from the MM/PBSA calculations. ZINC000085511995, a naphthoquinone had more negative binding free energy (−1068.26 kJ/mol) than inositol hexakisphosphate (IHP) [−873.873 kJ/mol], an agonist and a strong binder of ADAR2. The potential displacement of IHP by ZINC000085511995 in the IHP binding site of ADAR2 could be explored for possible deactivation of ADAR2. Bayesian-based biological activity prediction corroborates the neuropharmacological, antineoplastic and antiviral activity of the potential lead compounds. All the potential lead compounds, except ZINC000014612330 and ZINC000013462928, were predicted to be inhibitors of various deaminases. The potential lead compounds also had probability of activity (Pa) > 0.442 and probability of inactivity (Pi) < 0.116 values for treating acute neurologic disorders, except for ZINC000085996580 and ZINC000013462928. Pursuing these compounds for their anti-ADAR2 activities holds a promising future, especially against neurological disorders, some cancers and viral infections caused by RNA viruses. Molecular interaction, hydrogen bond and per-residue decomposition analyses predicted Arg400, Arg401, Lys519, Trp687, Glu689, and Lys690 as hot-spot residues in the ADAR2 IHP binding site. Most of the top compounds were observed to have naphthoquinone, indole, furanocoumarin or benzofuran moieties. Serotonin and tryptophan, which are beneficial in digestive regulation, improving sleep cycle and mood, are indole derivatives. These chemical series may have the potential to treat neurological disorders, prion diseases, some cancers, specific viral infections, metabolic disorders and eating disorders through the disruption of ADAR2 pathways. A total of nine potential lead compounds were shortlisted as plausible modulators of ADAR2.

The Behavioral Mapping of Psychomotor Slowing in Psychosis Demonstrates Heterogeneity Among Patients Suggesting Distinct Pathobiology

OBJECTIVES

Psychomotor slowing (PS) occurs in up to half of schizophrenia patients and is linked to poorer outcomes. As standard treatment fails to improve PS, novel approaches are needed. Here, we applied the RDoC framework using 3 units of analysis, ie, behavior, self-report, and physiology to test, whether patients with PS are different from patients without PS and controls.

METHODS

Motor behavior was compared between 71 schizophrenia patients with PS, 25 without PS, and 42 healthy controls (HC) using 5 different measures: (1) for behavior, an expert rating scale: Motor score of the Salpêtrière Retardation Rating Scale, (2) for self-report, the International Physical Activity Questionnaire; and for physiology, (3) Actigraphy, which accounts for gross motor behavior, (4) Gait velocity, and (5) coin rotation task to assess manual dexterity.

RESULTS

The ANCOVAs comparing the 3 groups revealed differences between patients with PS and HC in expert ratings, self-report, and instrumental measures (all P ≤ .001). Patients with PS also scored higher in expert ratings and had lower instrumental activity levels compared to patients without PS (all P ≤ .045). Instrumental activity levels correlated with an expert rating of PS (rho = -0.51, P-fdr corrected <.001) and classified similarly at 72% accuracy.

CONCLUSIONS

PS is characterized by slower gait, lower activity levels, and slower finger movements compared to HC. However, only actigraphy and observer ratings enable to clearly disentangle PS from non-PS patients. Actigraphy may become the standard assessment of PS in neuroimaging studies and clinical trials.

Psychomotor slowing alters gait velocity, cadence, and stride length and indicates negative symptom severity in psychosis

Schizophrenia is a severe mental disorder, in which 50% of the patients present with motor abnormalities such as psychomotor slowing. Slow spontaneous gait has been reported in schizophrenia. However, comprehensive objective instrumental assessments of multiple gait conditions are missing. Finally, the specific gait patterns of subjects with psychomotor slowing are still unknown. Therefore, this study aimed to objectively assess multiple gait parameters at different walking conditions in patients with schizophrenia with and without psychomotor slowing. Also, we hypothesised gait impairments to correlate with expert ratings of hypokinetic movement disorders and negative symptoms. We collected gait data (GAITRite®) in 70 patients with psychomotor slowing (SRRS (Salpetriere retardation rating scale) ≥15), 22 non-psychomotor slowed patients (SRRS < 15), and 42 healthy controls. Participants performed four walking conditions (self-selected speed, maximum speed, head reclined, and eyes closed) and six gait parameters were extracted (velocity, cadence, stride length, functional ambulation profile (FAP), and variance of stride length and time). Patients with psychomotor slowing presented slower velocity, lower cadence, and shorter stride length in all walking conditions compared to healthy controls, with the non-slowed patients in an intermediate position (all F > 16.18, all p < 0.001). Secondly, slower velocity was associated with more severe hypokinetic movement disorders and negative symptoms. In conclusion, gait impairments exist in a spectrum with healthy controls on one end and patients with psychomotor slowing on the other end. Patients with psychomotor slowing are specifically impaired when an adaptation of gait patterns is required, contributing to the deleterious effects of sedentary behaviours.

Validation of the Apraxia Screen TULIA (AST) in Schizophrenia

INTRODUCTION

Deficits in social interaction and community functioning, including impaired use, performance, and perception of hand gestures, are key features in schizophrenia. A well-established tool to assess gesture deficits is the test of upper limb apraxia (TULIA). However, given its time-consuming application based on video analyses, research has proposed the bedside apraxia screen of TULIA (AST). This study aims to test the validity and reliability of the AST to detect gesture abnormalities at bedside in a sample of 27 patients diagnosed with schizophrenia, schizotypal disorder, acute and transient psychotic disorders, or schizoaffective disorder.

METHODS

Patients completed the 48-item TULIA and the 12-item AST. Two different raters assessed the AST: one at bedside (online) and the other based on the video recordings.

RESULTS

The total AST scores demonstrated a high parallel reliability, moderate inter-rater reliability on a single-item level, and good construct validities.

CONCLUSIONS

The psychometric properties of the AST suggest it can well be used for the clinical assessment of gesture deficits in schizophrenia. However, when detailed information is required, the AST rated from video or conducting the full TULIA is recommended. The findings call for refining the selection of the TULIA items for a psychosis-AST bedside test to increase specificity.

Modelling neural entrainment and its persistence: influence of frequency of stimulation and phase at the stimulus offset

Neural entrainment, the synchronization of brain oscillations to the frequency of an external stimuli, is a key mechanism that shapes perceptual and cognitive processes.Objective.Using simulations, we investigated the dynamics of neural entrainment, particularly the period following the end of the stimulation, since the persistence (reverberation) of neural entrainment may condition future sensory representations based on predictions about stimulus rhythmicity.Methods.Neural entrainment was assessed using a modified Jansen-Rit neural mass model (NMM) of coupled cortical columns, in which the spectral features of the output resembled that of the electroencephalogram (EEG). We evaluated spectro-temporal features of entrainment as a function of the stimulation frequency, the resonant frequency of the neural populations comprising the NMM, and the coupling strength between cortical columns. Furthermore, we tested if the entrainment persistence depended on the phase of the EEG-like oscillation at the time the stimulus ended.Main Results.The entrainment of the column that received the stimulation was maximum when the frequency of the entrainer was within a narrow range around the resonant frequency of the column. When this occurred, entrainment persisted for several cycles after the stimulus terminated, and the propagation of the entrainment to other columns was facilitated. Propagation also depended on the resonant frequency of the second column, and the coupling strength between columns. The duration of the persistence of the entrainment depended on the phase of the neural oscillation at the time the entrainer terminated, such that falling phases (fromπ/2 to 3π/2 in a sine function) led to longer persistence than rising phases (from 0 toπ/2 and 3π/2 to 2π).Significance.The study bridges between models of neural oscillations and empirical electrophysiology, providing insights to the mechanisms underlying neural entrainment and the use of rhythmic sensory stimulation for neuroenhancement.

Using dynamic point light display stimuli to assess gesture deficits in schizophrenia

Background

Gesture deficits are ubiquitous in schizophrenia patients contributing to poor social communication and functional outcome. Given the dynamic nature of social communications, the current study aimed to explore the underlying socio-cognitive processes associated with point-light-displays (PLDs) of communicative gestures in the absence of any other confounding visual characteristics, and compare them to other well-established stimuli of gestures such as pictures by examining their association with symptom severity and motor-cognitive modalities.

Methods

We included 39-stable schizophrenia outpatients and 27-age-gender matched controls and assessed gesture processing using two tasks. The first task used static stimuli of pictures of a person performing a gesture. The limbs executing the gesture were missing and participants' task was to choose the correct gesture from three-options provided. The second task included videos of dynamic PLDs interacting with each other. One PLD performed communicative gestures, while the other PLD imitated/followed these performed gestures. Participants had to indicate, which of the two PLDs was imitating/following the other. Additionally, we evaluated symptom severity, as well as, motor and cognitive parameters.

Results

Patients underperformed in both gesture tasks compared to controls. Task performance for static stimuli was associated with blunted affect, motor coordination and sequencing domains, while PLD performance was associated with expressive gestures and sensory integration processes.

Discussion

Gesture representations of static and dynamic stimuli are associated with distinct processes contributing to poor social communication in schizophrenia, requiring novel therapeutic interventions. Such stimuli can easily be applied remotely for screening socio-cognitive deficits in schizophrenia.

Motor abnormalities are associated with poor social and functional outcomes in schizophrenia

BACKGROUND

Up to 50% of patients with schizophrenia are suffering from motor abnormalities, which may contribute to decreased quality of life, impaired work capacity, and a reduced life expectancy by 10-20 years. However, the effect of motor abnormalities on social and global functioning, as well as, functional capacity is not clear. We hypothesized, that the presence of motor abnormalities is associated with poorer functional outcomes in patients with schizophrenia.

METHODS

We collected data on 5 different motor abnormalities in 156 patients suffering from schizophrenia spectrum disorders: parkinsonism, catatonia, dyskinesia, neurological soft signs and psychomotor slowing (PS). Additionally, we used three different scales to evaluate the functional outcomes in these patients: the Global Assessment of Functioning (GAF) and the Social and Occupational Functioning Assessment Scale (SOFAS) which use clinicians' judgment; and one using a performance-based measure of functional capacity, the brief version of the UCSD Performance-based Skills Assessment (UPSA-B).

RESULTS

Our analysis demonstrated that patients with catatonia (all F > 4.5; p < 0.035) and parkinsonism (all F > 4.9; p < 0.027) scored lower on GAF and SOFAS compared to patients without catatonia and parkinsonism. In contrast, no significant difference on functional outcomes between patients with dyskinesia versus without dyskinesia exist in our study. Furthermore, there are statistically significant negative correlations for parkinsonism and PS with GAF, SOFAS and UPSA-B (all tau are at least -0.152, p-value <0.036). We also found significant negative correlations between catatonia and both GAF & SOFAS (all tau are at least -0.203, p-value<0.001) and between NES and SOFAS (tau = -0.137, p-value = 0.033).

CONCLUSION

Here, we showed that four of the most common motor abnormalities observed in schizophrenia were associated with at least one of the patients' functional outcomes. The stronger the motor impairment was the worse the global and social functioning. Future studies need to test, whether amelioration of motor abnormalities is linked to improved community functioning.

Low physical activity is associated with two hypokinetic motor abnormalities in psychosis

Individuals with schizophrenia engage in more sedentary behavior than healthy controls, which is thought to contribute to multiple health adversities. Age, medication side effects and environment are critical determinants of physical activity in psychosis. While motor abnormalities are frequently observed in psychosis, their association with low physical activity has received little interest. Here, we aimed to explore the association of actigraphy as an objective measure of physical activity with clinician assessed hypokinetic movement disorders such as parkinsonism and catatonia. Furthermore, we studied whether patients with current catatonia would differ on motor rating scales and actigraphy from patients without catatonia. In 52 patients with schizophrenia spectrum disorders, we cross-sectionally assessed physical activity using wrist actigraphy and ratings of catatonia, parkinsonism, and negative syndrome. The sample was enriched with subjects with severe psychomotor slowing. Lower activity levels correlated with increased age and severity of catatonia and parkinsonism. The 22 patients with catatonia had lower activity as well as higher scores on parkinsonism, involuntary movements, and negative symptoms compared to the 30 patients without catatonia. Collectively, these results suggest that various hypokinetic motor abnormalities are linked to lower physical activity. Therefore, future research should determine the direction of the associations between hypokinetic motor abnormalities and physical activity using longitudinal assessments and interventional trials.

Potential Locations for Non-Invasive Brain Stimulation in Treating Schizophrenia: A Resting-State Functional Connectivity Analysis

Introduction: Non-invasive brain stimulation (NIBS) techniques have been widely used for the purpose of improving clinical symptoms of schizophrenia. However, the ambiguous stimulation targets may limit the efficacy of NIBS for schizophrenia. Exploring effective stimulation targets may improve the clinical efficacy of NIBS in schizophrenia.

Methods: We first conducted a neurosynth-based meta-analysis of 715 functional magnetic resonance imaging studies to identify schizophrenia-related brain regions as regions of interest. Then, we performed the resting-state functional connectivity analysis in 32 patients with first-episode schizophrenia to find brain surface regions correlated with the regions of interest in three pipelines. Finally, the 10–20 system coordinates corresponding to the brain surface regions were considered as potential targets for NIBS.

Results: We identified several potential targets of NIBS, including the bilateral dorsal lateral prefrontal cortex, supplementary motor area, bilateral inferior parietal lobule, temporal pole, medial prefrontal cortex, precuneus, superior and middle temporal gyrus, and superior and middle occipital gyrus. Notably, the 10-20 system location of the bilateral dorsal lateral prefrontal cortex was posterior to F3 (F4), not F3 (F4).

Conclusion: Conclusively, our findings suggested that the stimulation locations corresponding to these potential targets might help clinicians optimize the application of NIBS therapy in individuals with schizophrenia.

Measuring catatonia motor behavior with objective instrumentation

OBJECTIVE

Catatonia is a neuropsychiatric syndrome, with important psychomotor features, associated with schizophrenia and other psychiatric disorders. The syndrome comprises multiple symptoms including abnormal motor control, behaviors, volition, and autonomic regulation. Catatonia assessment relies on clinical rating scales and clinicians familiar with the catatonia exam. However, objective instrumentation may aid the detection of catatonia. We aimed to investigate the relationship between movement parameters derived from actigraphy and expert ratings of catatonia symptoms measured by the Bush Francis Catatonia Rating Scale (BFCRS) and the Northoff Catatonia scale (NCS).

METHODS

Eighty-six acutely ill inpatients with schizophrenia spectrum disorders were assessed with the BFCRS, the NCS, and 24 h continuous actigraphy. Non-wear and sleep periods were removed from the actigraphy data prior to analysis. Associations between total catatonia scores, derived from both BFCRS and NCS, and actigraphy parameters as well as between single BFCRS items and actigraphy parameters were calculated using Spearman's rank correlation and non-parametric ANCOVAs (Quade's ANCOVAs), respectively.

RESULTS

Both higher BFCRS total scores (r = 0.369, p = 0.006) and NCS total scores (r = 0.384, p = 0.004) were associated with lower activity levels (AL). Higher scores on single BFCRS items such as immobility/stupor or staring were linked to lower AL (immobility/stupor: F = 17.388, p < 0.001, η² = 0.175; staring: F = 7.849, p = 0.001, η² = 0.162) and lower metabolic equivalents of task (MET).

CONCLUSION

Specific catatonia symptoms such as immobility/stupor and staring can be measured with actigraphy. This may aid the detection, staging, and monitoring of catatonia in clinical settings.

Brain Stimulation and Group Therapy to Improve Gesture and Social Skills in Schizophrenia-The Study Protocol of a Randomized, Sham-Controlled, Three-Arm, Double-Blind Trial

An important component of nonverbal communication is gesture performance, which is strongly impaired in 2/3 of patients with schizophrenia. Gesture deficits in schizophrenia are linked to poor social functioning and reduced quality of life. Therefore, interventions that can help alleviate these deficits in schizophrenia are crucial. Here, we describe an ongoing randomized, double-blind 3-arm, sham-controlled trial that combines two interventions to reduce gesture deficits in schizophrenia patients. The combined interventions are continuous theta burst stimulation (cTBS) and social cognitive remediation therapy (SCRT). We will randomize 72 patients with schizophrenia spectrum disorders in three different groups of 24 patients. The first group will receive real cTBS and real SCRT, the second group will receive sham cTBS and real SCRT, and finally the third group will receive sham SCRT. Here, the sham treatments are, as per definition, inactive interventions that mimic as closely as possible the real treatments (similar to placebo). In addition, 24 age- and gender-matched controls with no interventions will be added for comparison. Measures of nonverbal communication, social cognition, and multimodal brain imaging will be applied at baseline and after intervention. The main research aim of this project will be to test whether the combination of cTBS and SCRT improves gesture performance and social functioning in schizophrenia patients more than standalone cTBS, SCRT or sham psychotherapy. We hypothesize that the patient group receiving the combined interventions will be superior in improving gesture performance.

CLINICAL TRIAL REGISTRATION

[www.ClinicalTrials.gov], identifier [NCT04106427].

A systematic review of the prognostic value of motor abnormalities on clinical outcome in psychosis

Schizophrenia spectrum disorders have heterogeneous outcomes and currently no marker predicts the course of illness. Motor abnormalities (MAs) are inherent to psychosis, the risk of psychosis, symptom severity, and brain alterations. However, the prognostic value of MAs is still unresolved. Here, we provide a systematic review of longitudinal studies on the prognostic role of MAs spanning individuals at clinical high risk for psychosis (CHR), patients with first-episode psychosis (FEP), and chronic schizophrenia. We included 68 studies for a total of 23,630 subjects that assessed neurological soft signs (NSS), hypo- or hyperkinetic movement disorders and/or catatonia as a prognostic factor on clinical and functional outcomes. We found increased levels of MAs, in particular NSS, parkinsonism, and dyskinesia, were related to deteriorating symptomatic and poor functional outcome over time. Collectively, the findings emphasize the clinical, prognostic and scientific relevance of MA assessment and detection in individuals with or at risk of psychosis. In the future, instrumental measures of MA are expected to further augment detection, early intervention and treatment strategies in psychosis.

Hand gesture performance is impaired in major depressive disorder: A matter of working memory performance?

OBJECTIVE

Individuals with depression exhibit numerous interpersonal deficits. As effective use of gestures is critical for social communication, it is possible that depressed individuals' interpersonal deficits may be due to deficits in gesture performance. The present study thus compared gesture performance of depressed patients and controls and examined whether these deficits relate to cognitive and other domains of dysfunction.

METHODS

Gesture performance was evaluated in 30 depressed patients and 30 controls using the Test of Upper Limb Apraxia (TULIA). Clinical rating scales were assessed to determine if gesture deficits were associated with motor, cognitive or functional outcomes.

RESULTS

Compared to controls, depressed patients exhibited impaired gesture performance with 2/3 of the patients demonstrating gesture deficits. Within depressed patients, gesture performance was highly correlated with working memory abilities. In contrast, no association between gesture performance and gestural knowledge, psychomotor retardation, depression severity, or frontal dysfunction was observed in patients.

LIMITATIONS

This is a cross-sectional study and a larger size would have allowed for confident detection of more subtle, but potentially relevant effects.

CONCLUSION

Gesture performance is impaired in depressed patients, and appears to be related to poor working memory abilities, suggesting a disruption in the retrieval of gestural cues indicative of a distinct clinical phenomenon that might be related to social functioning.

Using Virtual Reality as a Tool in the Rehabilitation of Movement Abnormalities in Schizophrenia

Movement abnormalities are prevalent across all stages of schizophrenia contributing to poor social functioning and reduced quality of life. To date, treatments are scarce, often involving pharmacological agents, but none have been shown to improve movement abnormalities effectively. Virtual reality (VR) is a tool used to simulate virtual environments where behavioral performance can be quantified safely across different tasks while exerting control over stimulus delivery, feedback and measurement in real time. Sensory information is transmitted via a head mounted display allowing users to directly interact with virtual objects and bodies using gestures and body movements in the real world to perform different actions, permitting a sense of immersion in the simulated virtual environment. Although, VR has been widely used for successful motor rehabilitation in a variety of different neurological domains, none have been exploited for motor rehabilitation in schizophrenia. The objectives of this article are to review movement abnormalities specific to schizophrenia, and how VR can be utilized to restore and improve motor functioning in patients with schizophrenia. Constructing VR-mediated motor-cognitive interventions that can help in retaining and transferring the learned outcomes to real life are also discussed.

Nonverbal communication remains untouched: No beneficial effect of symptomatic improvement on poor gesture performance in schizophrenia

BACKGROUND

Gestures are an important part of communication. Patients with schizophrenia present gesture deficits that tend to deteriorate in the course of the disease and hamper functional outcome. This gesture deficit has been associated with motor abnormalities, cognitive impairment, and psychotic symptoms. Unaffected, first-degree relatives of schizophrenia patients share some subclinical motor and cognitive abnormalities. We aimed to investigate, whether gesture performance changes with symptomatic improvement in patients, and to test the longitudinal performance in unaffected, first-degree relatives.

METHODS

In this study, we measured gesture performance using a validated test in 33 patients, 29 first-degree relatives and 38 healthy controls. Measurements were completed shortly after admission and before discharge in patients. Performance was rated blindly by experts using video recordings of the gesture task. Additionally, we evaluated cognitive function and psychotic symptoms at both visits.

RESULTS

Gesture performance was poorer in relatives compared to controls and poorer in patients compared to both relatives and controls. Patients showed an improvement in psychopathology but a significant decrease in gesture performance at follow-up, while performance in the other groups remained stable. Proportional change of gesture performance correlated with change of cognitive function in patients, whereas there were no correlations with change of cognitive function in the other groups.

CONCLUSION

While symptom severity was reduced, the gesture deficit further deteriorated in schizophrenia. The finding argues for distinct processes contributing to poor nonverbal communication skills in patients, requiring novel alternative treatment efforts.