Cognitive Enhancement on Working Memory in Patients With Schizophrenia

Not Applicable

Completed

• Conditions: Schizophrenia; Neurostimulator; Complications; Memory Deficits
• Interventions: Device: STARSTIM

• Registration Number: NCT03872310
• Lead Sponsor: Taipei Medical University Shuang Ho Hospital

Brief Summary

The investigators plan to investigate the effect of enhancement on working memory (WM) in patients of chronic schizophrenia and determine the predictive factors of effective treatment.

Detailed Description

Schizophrenia is a chronic and disabling disease with a prevalence of 0.5%\~1.5% in the general population. It's estimated 98% of patients with schizophrenia exhibit variable degrees of cognitive deficits which have been well established to be predictive of patient functioning. A number of treatments had been developed for cognitive enhancement in patients with schizophrenia, nevertheless none of them showed satisfying results.

Transcranial direct current stimulation (tDCS) is a safe and convenient treatment which has showed some evidence of beneficial effects on working memory (WM) in both healthy and neuropsychiatric populations. However, studies of tDCS for cognitive enhancement in patients with schizophrenia are still quiet limited. The results of our previous studies in healthy participants and patients with diabetic polyneuropathy suggest that the anodal tDCS over right dorsolateral prefrontal cortex (DLPFC) improved spatial WM capacity, particularly when task difficulty demands more complex mental manipulations and for the low-performing patients in baseline assessments. Thus, we hypothesize that in the baseline the more severe the patients' cognitive deficit are, the greater their WM capacity improvement would be after applying the anodal Tdcs over right DLPFC.

The investigators plan to recruit 40 patients with chronic schizophrenia. First, the investigators will collect baseline characteristics including disease severity, cognitive deficits and brain connectivity. Then the investigators will adopt a sham-active crossover design for tDCS treatment with the order of the two sessions (sham and active) counterbalanced across participants. The investigators will perform pre- tDCS and post- tDCS assessments of their spatial WM and verbal WM as well as statistical analyses to see if the effect of cognitive enhancement reaches a significant level. In addition, the investigators will explore the possible predictive indicators of effective treatment.

Study Timeline

• Study First Submitted: 2019-03-11
• Study First Submitted QC: 2019-03-11
• Study First Posted: 2019-03-13
• Study Start: 2019-05-01
• Primary Completion: 2021-08-30
• Study Completion: 2021-08-30
• Status Verified: 2022-08
• Last Update Submitted: 2022-08-09
• Last Update Posted: 2022-08-11

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 28

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Active comparator	STARSTIM	Within group
Sham comparator	STARSTIM	Within group

Primary Outcome Measures

Name	Time	Method
Visual-spatial working memory span measured by Corsi Block-Tapping task	up to one hour	The paradigm was computer-adaptive, and thus the set size would only increase if the participant passed consecutive two trials of the same span. The lowest span level started from 2 (2 squares that change color) and up to 9 as maximum.
Verbal working memory measured by digit-span test	up to one hour	The paradigm was also computer-adaptive

Trial Locations

Locations (1)

Shuang-Ho Hospital; 🇨🇳 Taipei, Taiwan