Cognitive Effects in Chiari Malformation Type 1
Written by Maggie Bauer
Edited by Aaron Wright
March 21, 2022
Edited by Aaron Wright
March 21, 2022
Have you ever heard of Chiari Malformation? Neither had I until I was diagnosed with it two years ago. But in reality, Chiari Malformation is quite common. According to recent statistics, Chiari Malformation affects around “50,000 to 350,000 persons in the United States”. Chiari Malformation is a disorder in which the cerebellum of the brain descends into the brain stem, restructuring cerebrospinal fluid and putting pressure on the brain. In simpler terms, the brain doesn’t fit in the skull. The symptoms vary based on the patient, from severe headaches to blurred vision making the disorder hard to diagnose. Chiari Malformation Type I is just one type of this disease and was the topic of the study by Allen et al.
The first choice the researchers made was their sample population. Although the general classification convention for Chiari Malformation is if the tonsils, a part of the brain, “are descended by 5 mm” or more, there are still variances in diagnosing with some neurologists needing more evidence, such as other symptoms. The researchers chose patients who had already undergone decompression surgery, which is the treatment for disorder. This confirms that everyone in the study had to meet the standards to be diagnosed and required surgery. They were given a variety of neurological tests such as the Swoop test, in which color names are shown in the same color and in a different color to test response inhibition, and the Rey Auditory Verbal Learning Test (RAVLT) in which the test subjects had to recall words right after they heard them and “40 minutes” later measuring delayed recall in order to measure episodic memory recall. Researchers focused on factors such as response time, working memory, and accuracy. Their results were compared to a control group, who were matched by age and education level, and also completed these same tests. The data from these tests were analyzed and they found that there were deficits in the Chiari Malformation group in processing speed, working memory (where the brain stores information it is working on), and response inhibition when compared to the control group. But there are other factors that have to be taken into account. Chiari Malformation patients commonly still experience headaches and neck pain even after the surgery. This disorder is also associated with higher levels of depression and anxiety. When the researchers factored in these variables they found that only deficits in response inhibition were significant. This still leads to the conclusion that those with Chiari Malformation do experience cognitive deficits.
This study concludes with researchers leaving us with as many questions as they give answers. Although we know that cognitive defects are occurring, it still isn’t clear what is causing this. We also still don’t even know the cause of this disorder. With this new link not just to cognitive defects, but also chronic pain, depression, and anxiety there leaves much to be explained. We can see in this article evidence of how much we still don’t understand about these disorders, and how much there is to discover.