Cognitive dysfunction in young subjects who have a gene for frontotemporal dementia
This isn’t news but is rather an interesting thing I learned today. There is a family with an inherited form of frontotemporal dementia. In this family, the onset of dementia occurred between 57-63 years of age. A study was done which did psychological tests on members of this family. It was found that young people (younger than 35) who carried the gene for the disorder had measurable frontal-executive dysfunction (whereas controls, young people in the same family who did not carry the gene, did not have dysfunction).
Specifically,
“Carriers had significantly lower scores than noncarriers on verbal fluency, WCST categories completed, Stroop interference, and the WAIS-R similarities subtest. Performance results on the digit span subtest of the WAIS-R test and Trails B were also significantly lower in the carriers than in the noncarriers, consistent with studies of frontal lobe injury. Performance on Trails A did not significantly differ between the groups. Four of the mutation carriers actually performed in the pathological range on both WCST and verbal fluency (ie, at least 2 standard deviations below the norm), while the 6 noncarriers did not.”
Daniel H. Geschwind, MD, PhD, Janik Robidoux, PhD, Maricela Alarcón, PhD, Bruce L. Miller, MD, Kirk C. Wilhelmsen, MD, PhD, Jeffrey L. Cummings, MD, Ziad S. Nasreddine, MD. Dementia and neurodevelopmental predisposition: Cognitive dysfunction in presymptomatic subjects precedes dementia by decades in frontotemporal dementia. Annals of Neurology. Volume 50, Issue 6 , Pages 741 – 746. December 2001.