Transcranial Direct Current Stimulation (tDCS) Studies of Cognition, Oscillations and GABA Levels in Schizophrenia
University of California, Davis
Summary
People with schizophrenia often have problems with attention, learning and memory and other cognitive abilities that interfere with their work and school performance. Unfortunately, even our best treatments often do not significantly reduce these cognitive problems. The current study investigates whether or not delivering a very small electrical current to people's foreheads (called, transcranial direct current stimulation; (tDCS)) might improve functioning in the front part of the brain and reduce these cognitive problems in people with schizophrenia. tDCS is non-invasive and has been shown to improve cognitive functioning in some preliminary studies. The current study will investigate whether giving tDCS during a task is more effective than giving it during rest (Aim 1), whether delivery of tDCS to the front of the head is more effective than delivery to the back of the head (Aim 2), and whether tDCS delivery will alter levels of a major inhibitory neurotransmitter in the brain (GABA; Aim 3) that is important to cognitive functioning and may be disrupted in people with schizophrenia. Although this study is not intended to diagnose, cure or treat schizophrenia or any other disease, if results are positive it will encourage future large-scale studies to determine if tDCS can become an effective treatment for cognitive problems in people with schizophrenia.
Eligibility
- Age range
- 18–47 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Participants must be able to sufficiently speak and understand English so as to be able to understand and complete cognitive tasks. * All subjects must have the ability to give valid informed consent. Inclusion Criteria for Patients with Schizophrenia Only: * Diagnosis of schizophrenia, schizophreniform or schizoaffective disorder * No medication changes in the prior month * No medication changes anticipated in the upcoming month * Stable outpatient or partial hospital status * Normal IQ (\>70; IQ will be measured by administering the Wechsler Abbreviated Scale of * In…
Interventions
- DeviceTranscranial Direct Current Stimulation
In tDCS, saline-soaked electrodes are temporary affixed to the scalp and connected to a battery-powered current generator. A weak (2 mA) constant current is then briefly applied (\~20 minutes) to stimulate the targeted brain area (e.g. the DLPFC). To control for placebo effects, the study will utilize a sham stimulation protocol that consists of very brief constant stimulation (\~1 minute). Subjects usually cannot discern the difference between the sham and experimental stimulation protocols due to habituation.
Location
- Imaging Research CenterSacramento, California