Read on Twitter
Please RT!
FINALLY OUT in @alzdemjournals : DADM @wileyneurosci "A quadratic function of activation in individuals at risk of Alzheimer's disease".
For a little story https://bit.ly/362rcXJ
FINALLY OUT in @alzdemjournals : DADM @wileyneurosci "A quadratic function of activation in individuals at risk of Alzheimer's disease".
For a little story https://bit.ly/362rcXJ
In this study, we assessed the dynamics of brain activation and the presence of hyperactivation using task-related fMRI in SCD+ (those with reduced hippocampal volumes and / or APOE4 carriers) and MCI, which are believed to stand along the clinical spectrum of AD.
We found that left superior parietal activation followed a quadratic function in relation to disease severity proxies (neurodegeneration, memory performance) in a group combining SCD+ and MCI individuals.
This is consistent with the "inverted U-shaped" hypothesis which proposes that early hyperactivation found in the early stages of AD is followed by hypoactivation in late stages of the disease. https://link.springer.com/article/10.1007/s12017-009-8109-7
This was further confirmed by between-group comparisons, where we found hyperactivation in SCD+ and hypoactivation in MCI in this same brain area, compared to a group of healthy controls.
Other interesting results are: 1) We found that increased neurodegeneration was associated with increased hippocampal and right temporal activation, suggesting that hyperactivation is related to markers of disease progression;
and 2) we found hyperactivation in several hippocampal and temporoparietal areas in SCD +, thus indicating that this could represent an early biomarker of AD, before overt cognitive impairment.
We have a related paper currently under review in which we evaluated the latent patterns of functional connectivity related to hyperactivation and memory performance using the same sample. The results are quite fascinating. Stay tuned!
Thanks to the co-authors @SimonDuchesne, S. Gauthier, C. Hudon. M-J Kergoat, S. Mellah, & S. Belleville for this concerted effort which resulted in this great article.
One more thing: this article took 4 years of work and was rejected 4 times before it found its final publication destination. Never give up! It was very disheartening at times, but in the end, I'm very happy with how it turned out.
