Cognitive Effects of Transcranial Direct Current Stimulation (tDCS) and Transcranial Random Noise Stimulation (tRNS) in Schizophrenia: A Random, Crossover Study
Overview
- Phase
- Not Applicable
- Intervention
- transcranial direct current stimulation (tDCS) active stimulator
- Conditions
- Schizophrenia
- Sponsor
- The National Brain Mapping Laboratory (NBML)
- Enrollment
- 36
- Locations
- 2
- Primary Endpoint
- Spatial Working Memory behavioral performance
- Status
- Completed
- Last Updated
- last month
Overview
Brief Summary
The purpose of this study is to investigate the cognitive effects of different electrical stimulation modalities, such as transcranial direct and random-noise stimulation over the dorsolateral prefrontal cortex, in schizophrenia.
Investigators
Mohammad Ali Salehinejad
Principal Investigator
The National Brain Mapping Laboratory (NBML)
Eligibility Criteria
Inclusion Criteria
- •Diagnosis of schizophrenia based on Diagnostic and Statistical Manual (DSM)5
- •Being 18-50 years old (male and female)
- •If female, negative urine pregnancy test
- •feasibility for tDCS/tRNS interventions according to safety guidelines
- •stable medication regime, especially for classical neuroleptics and all central nervous system activating medications, if taken, 4-6 weeks before the experiment
- •fluency in the native language
- •right-handed
- •Required written informed consent signed by patients' guardian
Exclusion Criteria
- •pregnancy
- •alcohol or substance dependence
- •comorbid bipolar disorder and mood disorder
- •history of seizure
- •history of neurological disorder
- •history of head injury
- •Presence of ferromagnetic objects in the body that are contraindicated for brain stimulation of the head (pacemakers or other implanted electrical devices, brain stimulators, some types of dental implants, aneurysm clips, metallic prostheses, permanent eyeliner, implanted delivery pump, or shrapnel fragments)
Arms & Interventions
tDCS group
In tDCS, direct electrical currents at the intensity of 2 mA are generated by an electrical stimulator and are noninvasively delivered to the left and right dorsolateral prefrontal cortex through a pair of saline-soaked sponge electrodes (7×5 cm) for 30 minutes.
Intervention: transcranial direct current stimulation (tDCS) active stimulator
tRNS group
In tRNS, direct electrical currents at the intensity of 2 mA amplitude (offset at 1 mA) and frequency of 100-640 Hz are generated by an electrical stimulator and are noninvasively delivered to the left and right dorsolateral prefrontal cortex through a pair of saline-soaked sponge electrodes (7×5 cm) for 30 minutes.
Intervention: transcranial random noise stimulation (tRNS)
sham group
In sham group, placebo stimulation is generated by an electrical stimulator and is noninvasively delivered to the left and right dorsolateral prefrontal cortex through a pair of saline-soaked sponge electrodes (7×5 cm) for 30 minutes.
Intervention: transcranial direct current stimulation (tDCS) sham stimulator
Outcomes
Primary Outcomes
Spatial Working Memory behavioral performance
Time Frame: During procedure (4 minutes)
The test begins with a number of coloured squares (boxes) shown on the screen. The aim of this test is that by selecting the boxes and using a process of elimination, the participant should find one yellow 'token' in each of a number of boxes and use them to fill up an empty column on the right-hand side of the screen.
executive function behavioral performance
Time Frame: During procedure (8-10 minutes)
The participant is shown two displays containing three coloured balls. The test administrator first demonstrates to the participant how to move the balls in the lower display to copy the pattern in the upper display and completes one demonstration problem, where the solution requires one move. The participant must then complete three further problems, one each requiring two moves, three moves, and four moves. Next, the participant is shown further problems and must work out in their head how many moves the solutions require and then select the appropriate box at the bottom of the screen to indicate their response
The Positive and Negative Affect Schedule (PANAS)
Time Frame: through study completion, an average of 3 weeks
The Positive and Negative Affect Schedule (PANAS) is a self-report questionnaire that consists of two 10-item scales to measure both positive and negative affect. Each item is rated on a 5-point scale of 1 (not at all) to 5 (very much).