Accelerated DMN-targeted cTBS improves processing speed deficits in schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Cognitive deficits, particularly in information processing speed, are a major cause of disability in schizophrenia.
• The neural basis of these deficits is poorly understood, though Default Mode Network (DMN) hyperconnectivity is implicated.
• Current treatments for cognitive deficits in schizophrenia are limited.

Purpose of the Study:

• To investigate if transcranial magnetic stimulation (TMS) targeting the Default Mode Network (DMN) can improve processing speed in individuals with schizophrenia.
• To explore the relationship between DMN connectivity modulation and processing speed improvements.
• To assess the impact of age on treatment response.

Main Methods:

• Two studies were conducted: one with single TMS sessions (iTBS, cTBS, sham) and another with accelerated multi-session cTBS.
• Participants included individuals with schizophrenia and non-psychosis controls.
• Resting-state neuroimaging and processing speed assessments (Brief Assessment of Cognition in Schizophrenia digit symbol coding) were performed before and after TMS.

Main Results:

• Multi-session, DMN-targeted cTBS significantly improved processing speed in the schizophrenia group (p=0.0124).
• Reduced DMN connectivity correlated with enhanced processing speed in individuals with schizophrenia (p=0.021).
• Younger participants showed greater processing speed improvements than older participants (p=0.006).

Conclusions:

• Personalized, network-targeted TMS, specifically DMN-targeted cTBS, shows promise as a novel treatment for cognitive impairment in schizophrenia.
• Modulating DMN connectivity may be a viable strategy for improving processing speed.
• Age is a significant factor influencing treatment outcomes.