tdcs and cognitive training intervention for chronic smokers with schizophrenia

Conditions: Transcranial Direct Current Stimulation; Smoking, Cigarette; Schizophrenia

Summary: this study is being done to develop new methods to help smokers with schizophrenia to successfully reduce their smoking and/or quit. this is not a treatment study, but will help find new techniques to create better treatments. specifically, the investigators are interested in learning more about how thoughts and attention problems associated with schizophrenia might play a role in smoking, as well as the impact of cognitive (thinking, reasoning, and remembering) training and brain stimulation on these symptoms and on actual smoking.

adults with severe mental illness (smi) are three times more likely to smoke than non-smi adults, consuming 35-44% of all cigarettes in the u.s.; and, the highest rates of tobacco-related illnesses and death are among smokers with schizophrenia. unfortunately, not only are patients with schizophrenia less likely to receive smoking treatments, but cessation medications are only modestly effective in helping this subset of smokers quit. therefore, it is vital to discover new treatment adjuncts that specifically aid this high-risk subset of smokers to achieve successful abstinence. toward that end, the investigators propose a novel non-pharmacologic technique that directly targets both cognitive impairment, an avenue considerable past research suggests may be particularly effective to exploit in smokers with schizophrenia, and reactivity to prepotent stimuli, shown to be enhanced in smokers with schizophrenia. combining a subset of cognitive enhancement therapy known as cognitive remediation (cr), with another safe and effective technique, transcranial direct current stimulation (tdcs), the investigators propose a new cognitive training method aimed at enabling smokers with schizophrenia to gain greater control over smoking and stimuli-induced reactivity (e.g., craving). recent studies have found significant tdcs-induced cognitive enhancement, as well as reduction in both cue-induced craving and smoking behavior among healthy smokers. this combined with knowledge of the cognitive deficits that exist among individuals with schizophrenia, and clear evidence of a relationship between cognitive function and smoking treatment success, provides the rationale for testing novel cr + tdcs to target underlying mechanisms of smoking among individuals with schizophrenia. specifically, the proposed study will examine the extent to which targeted cognitive enhancement with cr + tdcs, leads to changes in cognitive control, cue-provoked craving, reaction time and erp measures of attentional bias; as well as the impact of these changes on smoking behavior and intention and confidence to quit among 80 smokers with schizophrenia. the goal of this study is to inform the development of new non-medication, noninvasive, therapeutic techniques to specifically target smoking among patients with schizophrenia. the long term goal is to establish an effective treatment adjunct to help smokers with schizophrenia successfully achieve abstinence.

Eligibility criteria:
inclusion criteria: * currently meets dsm-5 criteria for schizophrenia, schizoaffective disorder, schizophreniform disorder, or delusional disorder. * ability to provide written informed consent * smoke ≥ 7 cigarettes per day * expired breath co ≥ 10 ppm at screening * stable medication regimen for ≥ 4 weeks (if on more than one psychotropic medication, main antipsychotic will be considered for stability) exclusion criteria: * epilepsy or current seizure disorder * alcohol or substance dependence past 3 months (caffeine allowed, nicotine is part of inclusion criteria). * pregnant or lactating * psychiatric hospitalization in past 3 months * suicidal and/or aggressive behavior past 3 months * implanted cardiac or brain medical devices * latex allergy * scalp irritation or recent shaving of scalp * use of other smoking cessation medication * history of head trauma * history of ect

Keywords: transcranial direct current stimulation smoking schizophrenia