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

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.

Timeline

Start

2011-11

Primary completion

2013-04

Completion

2013-04

Publications

• Background Weinberger DR, Berman KF, Zec RF. Physiologic dysfunction of dorsolateral prefrontal cortex in schizophrenia. I. Regional cerebral blood flow evidence. Arch Gen Psychiatry. 1986 Feb;43(2):114-24. doi: 10.1001/archpsyc.1986.01800020020004.
• Background Green MF. Cognitive impairment and functional outcome in schizophrenia and bipolar disorder. J Clin Psychiatry. 2006;67 Suppl 9:3-8; discussion 36-42.
• Background Moss TG, Sacco KA, Allen TM, Weinberger AH, Vessicchio JC, George TP. Prefrontal cognitive dysfunction is associated with tobacco dependence treatment failure in smokers with schizophrenia. Drug Alcohol Depend. 2009 Sep 1;104(1-2):94-9. doi: 10.1016/j.drugalcdep.2009.04.005. Epub 2009 May 17.
• Background Wing VC, Sacco KA, George TP. Spatial working memory impairments induced by cigarette smoking abstinence are correlated with plasma nicotine levels in schizophrenia. Schizophr Res. 2011 May;128(1-3):171-2. doi: 10.1016/j.schres.2010.10.011. Epub 2010 Nov 13. No abstract available.
• Background Lewis DA, Gonzalez-Burgos G. Neuroplasticity of neocortical circuits in schizophrenia. Neuropsychopharmacology. 2008 Jan;33(1):141-65. doi: 10.1038/sj.npp.1301563. Epub 2007 Sep 5.
• Background Daskalakis ZJ, Christensen BK, Fitzgerald PB, Chen R. Dysfunctional neural plasticity in patients with schizophrenia. Arch Gen Psychiatry. 2008 Apr;65(4):378-85. doi: 10.1001/archpsyc.65.4.378.
• Background Thirugnanasambandam N, Grundey J, Adam K, Drees A, Skwirba AC, Lang N, Paulus W, Nitsche MA. Nicotinergic impact on focal and non-focal neuroplasticity induced by non-invasive brain stimulation in non-smoking humans. Neuropsychopharmacology. 2011 Mar;36(4):879-86. doi: 10.1038/npp.2010.227. Epub 2010 Dec 15.
• Background Farzan F, Barr MS, Levinson AJ, Chen R, Wong W, Fitzgerald PB, Daskalakis ZJ. Reliability of long-interval cortical inhibition in healthy human subjects: a TMS-EEG study. J Neurophysiol. 2010 Sep;104(3):1339-46. doi: 10.1152/jn.00279.2010. Epub 2010 Jun 23.
• Background Stefan K, Kunesch E, Cohen LG, Benecke R, Classen J. Induction of plasticity in the human motor cortex by paired associative stimulation. Brain. 2000 Mar;123 Pt 3:572-84. doi: 10.1093/brain/123.3.572.
• Background Farzan F, Barr MS, Levinson AJ, Chen R, Wong W, Fitzgerald PB, Daskalakis ZJ. Evidence for gamma inhibition deficits in the dorsolateral prefrontal cortex of patients with schizophrenia. Brain. 2010 May;133(Pt 5):1505-14. doi: 10.1093/brain/awq046. Epub 2010 Mar 28.

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