Working Memory Dysfunction: An fMRI Analysis in Schizophrenia

This thesis explores the relationship between brain activation and decreased performance in working memory in schizophrenia. This study analyzed differences in brain activation patterns during a working memory task-based fMRI comparing individuals with schizophrenia to healthy controls. Participants (n = 53) completed a working memory n-back paradigm while in an fMRI where they completed three levels that increased in working memory load; 0back, 1back, and 2back. Python analysis of fMRI data compared brain activation maps of individuals with schizophrenia (n = 22) to healthy controls (n = 31) during the different levels of the nback task. D prime of task scores accuracy was calculated and compared between groups. Through analysis of fMRI 2 group sample maps, individuals with schizophrenia showed greater overall activation specifically in areas of the default mode network (DMN) demonstrating that during working memory individuals with schizophrenia have an impaired ability to deactivate the DMN. Similarly, individuals with schizophrenia showed a significantly lower accuracy and decreased performance on the nback task. Understanding brain activation differences during working memory in schizophrenia is important in understanding the prevalent cognitive deficits and memory impairment symptoms. This can lead to development of specific risk markers identifiable before the onset of psychosis and effective treatment plans targeting memory symptoms. This study contributes to the understanding of the circuitry involved in working memory deficits and can be predictive of greater cognitive decline within individuals with schizophrenia.