Single Session Transcranial Magnetic Stimulation Ameliorates Hand Gesture Deficits in Schizophrenia

Abstract

Social interaction is impaired in schizophrenia, including the use of hand gestures, which is linked to poor social perception and outcome. Brain imaging suggests reduced neural activity in a left-lateralized frontoparietal network during gesture preparation; therefore, gesturing might be improved through facilitation of left hemispheric brain areas or via disruption of interhemispheric inhibition from the right homolog. This study tested whether repetitive transcranial magnetic stimulation (rTMS) protocols would improve gesture performance in schizophrenia. This randomized, placebo-controlled, double-blind, crossover trial applied 3 different protocols of rTMS separated by 48 h. Twenty right-handed schizophrenia patients and 20 matched healthy controls received facilitatory intermittent theta burst stimulation (iTBS) over the left inferior frontal gyrus (IFG), inhibitory continuous theta burst stimulation (cTBS) over right inferior parietal lobe (IPL), and placebo over left IPL in randomized order. Primary outcome was change in the test of upper limb apraxia (TULIA), rated from video recordings of hand gesture performance. Secondary outcome was change in manual dexterity using the coin rotation task. Participants improved on both tasks following rTMS compared with baseline. Only patients improved gesture performance following right IPL cTBS compared with placebo (P = .013). The results of the coin rotation parallel those of the TULIA, with improvements following right IPL cTBS in patients (P = .001). Single sessions of cTBS on the right IPL substantially improved both gesture performance accuracy and manual dexterity. The findings point toward an inhibition of interhemispheric rivalry as a potential mechanism of action.

Transcranial direct current stimulation improves action-outcome monitoring in schizophrenia spectrum disorder

“…Thus, cathodal stimulation of the left hemisphere and anodal stimulation of the right hemisphere leads to disadvantages in the delay-detection task for HC (see also, Straube et al , 2017 a ), but results in better performance in patients. It might be the case that results are affected by group differences in interhemispheric rivalry, which have been reported in repetitive transcranial magnetic stimulation studies for neglect ( Nyffeler et al , 2019 ), in gesture performance in healthy subjects ( Vanbellingen et al , 2020 ) and in schizophrenia ( Walther et al , 2020 ). Thus, stimulation of a brain area may inhibit the homologue of the other hemisphere (and vice versa).…”

Emotion Recognition Deficits in Psychiatric Disorders as a Target of Non-invasive Neuromodulation: A Systematic Review

“…Social perception. The profile of nonverbal sensitivity (PONS) 31 is used to assess social perception, linked to social interaction, 23 using scenes with facial expressions, voice intonations, and/or bodily gestures. The test of upper limb apraxia (TULIA) 32 was used to assess the accuracy of performance of 48 hand gestures (meaningless, intransitive, or transitive), half of which are performed on demonstration of the experimenter (imitation), whereas the other half are performed following verbal instructions (pantomime).…”

“…Among 3 tDCS studies, two of which found significant effects only in emotion recognition, one of which targeted depression 25 and the other targeted schizophrenia, 22 as shown in Table 1. 23,24 used the same parameters among active and sham groups. "Significant effects in social perception" meant that stimulation enhanced the ability to assess the accuracy of performance of hand gestures.…”

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

“…This suggests that pharmacological treatments may not be ideal candidates and offer no long-term solution in taming movement abnormalities. Preliminary findings suggest non-invasive brain stimulation (NIBS) is a potential candidate in alleviating movement abnormalities in schizophrenia patients ( Walther et al, 2020a , c ). Several ongoing clinical trials are currently administered to further assess the efficacy of NIBS ( Lefebvre et al, 2020 ); Personalized Non-invasive Neuromodulation by rTMS for Chronic and Treatment-Resistant Catatonia trial (RETONIC, NCT03116425), Overcoming Psychomotor Slowing in Psychosis trial (OCoPS-P, NCT03921450), and Brain Stimulation And Group Therapy to Improve Gesture and Social Skills in Psychosis trial (BrAGG-SoS, NCT04106427).…”