NCT05342727

Transcranial Direct and Alternating Stimulation of the Prefrontal Cortex for Cognitive Improvement in Schizophrenia

The Impact of Transcranial Direct and Alternating Stimulation of the Prefrontal Cortex at Different Intensities and Frequencies on Cognition of Schizophrenic Patients

• Status: Completed
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 50 (actual)
• Sponsor: The National Brain Mapping Laboratory (NBML) · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to investigate different stimulation intensities and frequencies of transcranial direct and alternating current stimulation over the dorsolateral prefrontal cortex for cognitive improvement in schizophrenia.

Detailed description

In this randomized, double-blind study, 50 patients diagnosed with schizophrenia are randomly assigned into two arms. The first group receives transcranial direct current stimulation (tDCS) at three intensities (2 mA, 3 mA, and sham) and the second group receives transcranial alternating current stimulation (tACS) at three different frequencies (8 Hz, 40 Hz, and sham) over the left dorsolateral prefrontal cortex for 20 min. There are at least 72 hours between stimulation sessions. The patients conduct three cognitive tasks from the CANTAB neuropsychological battery for schizophrenia during stimulation including a working memory task, a cognitive flexibility task, and an emotion recognition task. Mood stability is also evaluated before and after each stimulation session with the Positive and Negative Affect Scale (PANAS).

Conditions

• Schizophrenia
• Cognitive Dysfunction

Interventions

Type	Name	Description
DEVICE	transcranial direct current stimulation (tDCS)	In tDCS, direct electrical currents at the intensity of interest (2 mA for example) are generated by an electrical stimulator and are noninvasively delivered to the scalp through a pair of saline-soaked sponge electrodes (7×5 cm).
DEVICE	transcranial alternating current stimulation (tACS)	In tACS, alternating electrical currents at the frequency of interest (8 Hz for example) are generated by an electrical stimulator and are noninvasively delivered to the scalp through a pair of saline-soaked sponge electrodes (7×5 cm).

Timeline

• Start date: 2021-04-01
• Primary completion: 2022-07-15
• Completion: 2022-07-31
• First posted: 2022-04-25
• Last updated: 2022-08-08

Locations

1 site across 1 country: Iran