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

Abstract

Background. Social cognition deficits are a core feature of psychiatric disorders, such as schizophrenia and mood disorder, and deteriorate the functionality of patients. However, no definite strategy has been established to treat social cognition (eg, emotion recognition) impairments in these illnesses. Here, we provide a systematic review of the literature regarding transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) for the treatment of social cognition deficits in individuals with psychiatric disorders. Methods. A literature search was conducted on English articles identified by PubMed, PsycINFO, and Web of Science databases, according to the guidelines of the PRISMA statement. We defined the inclusion criteria as follows: (1) randomized controlled trials (RCTs), (2) targeting patients with psychiatric disorders (included in F20-F39 of the 10th revision of the International Statistical Classification of Diseases and Related Health Problems [ICD-10]), (3) evaluating the effect of tDCS or rTMS, (4) reporting at least one standardized social cognition test. Results. Five papers (3 articles on tDCS and 2 articles on rTMS) met the inclusion criteria which deal with schizophrenia or depression. The significant effects of tDCS or rTMS targeting the left dorsolateral prefrontal cortex on the emotion recognition domain were reported in patients with schizophrenia or depression. In addition, rTMS on the right inferior parietal lobe was shown to ameliorate social perception impairments of schizophrenia. Conclusions. tDCS and rTMS may enhance some domains of social cognition in patients with psychiatric disorders. Further research is warranted to identify optimal parameters to maximize the cognitive benefits of these neuromodulation methods.

Transcranial Direct Current Stimulation on the Left Superior Temporal Sulcus Improves Social Cognition in Schizophrenia: An Open-Label Study

“…The effect sizes of tDCS for this benefit were about 0.5 SD) (Table 5), which is considered clinically meaningful (7). By contrast, its immediate effects after 1-2 sessions tDCS have been reported not to improve social cognitive disturbances (Table 1) (13,(17)(18)(19). As social cognition is considered to be directly linked to realworld social functioning (3,10), multisession tDCS, rather than single-session tDCS, may provide benefits for functional recovery in patients with schizophrenia.…”

“…So far, three studies have been conducted to examine the ability of tDCS to improve social cognitive disturbances of schizophrenia (see Table 1) (13,(17)(18)(19). Among them, only one study reported facilitative effects of stimulation on the left prefrontal cortex on emotion recognition (19).…”

“…Most studies reporting positive results on neurocognitive function have used the DLPFC for anodal stimulation (15). As noted above, three studies have been conducted to determine the effect of tDCS targeting frontal cortical areas on social cognitive disturbances of schizophrenia (see Table 1) (13,(17)(18)(19). Among them, only one study reported facilitative effects of tDCS on emotion recognition with the Fp1 as the anodal site (19).…”

“…To overcome social cognitive disturbances of schizophrenia, psychosocial (e.g., cognitive rehabilitation) ( 11 ) and pharmacological (e.g., second-generation antipsychotic drugs) ( 12 ) approaches have been attempted with limited success. As an alternative approach, some types of neuromodulations, particularly non-invasive brain stimulation, e.g., transcranial direct current stimulation (tDCS), have been drawing attention ( 13 ). tDCS modulates neural activities in the brain by delivering low-amplitude (usually no more than 2 mA) electrical currents over a short period (generally no more than 30 min) between electrodes, i.e., anode and cathode ( 14 ).…”

White matter association tracts underlying language and theory of mind: An investigation of 809 brains from the Human Connectome Project

“…the arcuate fasciculus (AF)) may support both language and ToM networks. Finally, we note that recent lesion analysis studies and cognitive stimulation mapping results also point to more broadly distributed cortical regions and additional white matter tracts involved in supporting these functions ( Drane and Pedersen, 2019 ; Yamada et al, 2021 ) than reflected by the classical models (i.e., language models that connect Wernicke’s to Broca’s area via the AF Geschwind, 1970 and ToM models that include the right temporal parietal junction as a critical hub Saxe and Wexler, 2005 ).…”