Effects of Acute Nicotine Treatment on Neuroplasticity and Memory in Patients With Schizophrenia

• Status: Terminated
• Trial end date: 2013-04-01
• Target enrollment: 0
• Participant gender: All

Summary

Patients with schizophrenia display cognitive impairments, such as reduced attention and problems with memory. Available medications for schizophrenia poorly alleviate memory problems however, research indicates that nicotine improves memory. In order for there to be memories formed, there has to be changes (neuroplasticity changes) in how the brain cells communicate. One way to induce such changes is by using Transcranial Magnetic Stimulation (TMS) combined with peripheral nerve stimulation in a Paired Associative Stimulation (PAS) paradigm. The investigators laboratory has developed a novel method that measures memory-like brain changes using electroencephalography (EEG), TMS and PAS. The present study will use this novel method to evaluate the effects of acute nicotine gum (4mg) and placebo (regular) gum on memory and memory-like brain changes in schizophrenia and healthy controls. The hypothesis is that nicotine will improve memory and facilitate neuroplasticity changes in the prefrontal cortex of patients with schizophrenia to a larger extent than in healthy controls.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Centre for Addiction and Mental Health
• Treatments: Nicotine

Criteria

Inclusion criteria:

• Age of 18-55 years

• Non-smoker or past smoker, abstinent for at least the last 1 year, non-smoking status will be assessed on the test days by saliva cotinine levels <15ng/mL and exhalation CO levels <10ppm.

• Females with potential childbearing must have a negative urine pregnancy test at inclusion.

• Women with child-bearing potential must use contraceptives during the trial Acceptable means of contraception are hormonal methods (pill, injection, vaginal ring), male or female condom, abstinence, injectable contraceptives, intrauterine devices or abstinence.

• Ability and willingness to speak English

• Willingness to provide informed consent

• Adequate hearing and visual capacity, or corrected by visual/ hearing aid • Right handedness

Patients with schizophrenia:

• Current diagnosis of schizophrenia or schizoaffective disorder according to DSM-IV TR criteria

• Stable antipsychotic treatment or dosage for the past 4 weeks prior to study entry

• Clinically stable, i.e. no psychotic episode that required hospitalization within the last 3 months prior to study inclusion

Exclusion Criteria:

General

• Current smoker or abstinent smoker for less than 1 year

• Past or current history of drug abuse disorder or current elicit drug use, positive urine drug screen (for any other drug besides benzodiazepines) on any of the two test days

• Current or past history of neurological disorder, i.e. meets criteria for a cognitive disorder secondary to a neurological or other medical disorder affecting the central nervous system (such as, traumatic brain injury, stroke, Parkinson).

• Current or past history of seizures

• Any metal implants

• Mini Mental Status Examination score of ≤17

• Diagnosis of bipolar disorder or current major depressive episode

• Electroconvulsive Therapy (ECT) within 6 months prior to study participation

• Allergy to any of the following: nicotine resin, xylitol, butylhydroxythyolen E 321, sodium carbonate, corn starch, magnesium oxide, D&C Yellow No 10, menthol, acesulfam potassium, wax, titan oxide, maltitol, sorbitol, gum base, sucralose, palm oil, mannitol, glycerin, calcium carbonate, gum arabic.

• Any of the following; breast feeding, immediate post-myocardial infarction period, life-threatening arrhythmias, angina pectoris, and active temporomandibular joint disease, oral or pharyngeal inflammation, or history of esophagitis or peptic ulcer.

Healthy controls:

• Any psychiatric diagnosis except for simple phobias or an adjustment disorder as diagnosed by DSM IV TR

• Psychotropic medication (except for sedative /hypnotics at a stable dose for at least 4 weeks).

• Sedative /hypnotics at a stable dose less than 4 weeks

• A first-degree relative with as past or present history of primary psychotic disorder