Clinical trial NCT02426983: Pilot Study Using an NMDA Antagonist to Modulate Transcranial Direct Current Stimulation (tDCS) Effects on Sensory Discrimination
Official title: A Pilot Study Using an NMDA Antagonist to Modulate Transcranial Direct Current Stimulation (tDCS) Effects on Auditory Sensory Memory Processing
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: PHASE1
PHASE2
Conditions: Schizophrenia
Lead sponsor: University of Ottawa
Sponsor class: OTHER
First posted: 2015-04-27
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER

Brief summary: Transcranial direct current stimulation (tDCS) is a non-invasive form of brain stimulation which uses a very weak constant current to temporarily excite the brain area of interest via small electrodes placed on the scalp. Currently, tDCS is being used as a tool to investigate mental processes (cognition) and motor function (movement) in healthy controls and to treat neurological (i.e. stroke) and psychiatric (i.e. depression and dementia) patients. tDCS has been found to improve motor processes and cognitive performance, including attention and memory functions. This study will attempt to examine the effects of tDCS on a specific aspect of short term memory to sounds measured from electrical activity (EEG) from the top of the scalp. This study will also assess the effect of a drug, dextromethorphan (DMO), commonly found in cough syrup, which is thought to regulate tDCS treatment through brain receptors. The study involves four laboratory test sessions. EEG assessments will be done in two sessions involving 'anodal' tDCS stimulation (to temporarily excite cortical activity locally), one session with DMO treatment and one with placebo treatment, and two sessions involving 'sham' tDCS stimulation (device is turned off), with the same DMO and placebo treatments. These findings will contribute to our understanding of the brain chemistry involved in tDCS treatment and its effects on cognitive abilities.


Eligibility criteria: Inclusion Criteria:

* Healthy, medication free
* Non-smoker
* Right-handed

Exclusion Criteria:

* Any current or past Axis I or Axis II disorder including a current or recent history of alcohol/substance abuse
* A clinically significant medical illness or organic brain disorder known to cause psychosis or cognitive impairment
* Any neurological diagnosis (including epilepsy)
* Recent head trauma (\<6 months)
* Metallic implants or any electrical device (e.g., pacemaker) in the body
* Major learning disability
* Body mass index \>38kg/m¬2
* Use of illicit drugs
* Abnormal hearing

Primary outcomes:
measure: MMN ERP amplitudes as a measure of sensory processing changes
timeFrame: 1 year
measure: Adverse Events Scores as measure of treatment side effects
timeFrame: 1 year
Secondary outcomes:
Other outcomes:
Locations:
city: Ottawa
country: Canada
facility: University of Ottawa Institute of Mental Health Research
state: Ontario
Study officials:
affiliation: University of Ottawa
name: Danielle Impey, Ph.D. (cand.)
role: PRINCIPAL_INVESTIGATOR
References: