Recent Advances in Understanding Cognitive Impairment in Schizophrenia

People with schizophrenia have a wide range of positive and negative symptoms including delusions, hallucinations, fatigue, emotional inexpressiveness, and impaired cognitive functioning. The medications commonly prescribed are mostly targeted to treat the positive symptoms (hallucinations, delusions), but the side effects tend to worsen some of the negative symptoms and don’t even touch cognition impairments.  Recently, more research has been done to investigate the impairments and mechanisms driving these cognitive impairments such as poor memory.

In 2016, the article, “Brain marker of poor memory in schizophrenia patients identified”, from ScienceDaily came out. In this article, the author describes research performed to expand on previous fMRI attempts to see if the dorsolateral prefrontal cortex (DLPFC) is directly involved in the cognitive memory impairments seen in schizophrenia patients. Though the research has been done before, no conclusive evidence was found to support this idea. This time researchers proposed that there may not have been differences because the test administered did not have enough levels of difficulties for the memory tasks. This would imply that in normal memory functioning, there may be a gradual activation or a necessary threshold at some point in the memory task for the DLPFC to activate significantly. If the research prior to this study did not reach that threshold or have enough difficulty levels to compare against in healthy individuals, this would explain not seeing any significant changes in the DLPFC between the control and schizophrenia groups. 

In the recent study, they had healthy individual controls, medicated schizophrenia patients, and nonmedicated schizophrenia patents. Each group underwent single word memory tasks while undergoing fMRI imaging and the memory tasks had eight levels of difficulty. The results showed significantly less activation both schizophrenia groups compared to the healthy individuals. The lower activation corresponded to difficulty with the memory tasks. This was the first study to identify the DLPFC as brain marker for one of the cognitive impairments in schizophrenia patients. The findings are a great step in the right direction but questions still remain to be answered. Why is the DLPFC responsible for this impairment? How is the DLPFC regulated in schizophrenia patients as opposed to healthy individuals? Hopefully advances in this field continue to bring insight to this issue.  

Citation: Columbia University Medical Center. (2016, April 4). Brain marker of poor memory in schizophrenia patients identified: Possible key to understanding, treating cognitive symptoms of disease. ScienceDaily. Retrieved February 22, 2020 from www.sciencedaily.com/releases/2016/04/160404143843.htm

URL: https://www.sciencedaily.com/releases/2016/04/160404143843.htm