Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
Cambridge Centre for Ageing and Neuroscience (Cam-CAN), University of Cambridge and MRC Cognition and Brain Sciences Unit, Cambridge, UK.
Alzheimers Dement. 2021 Mar;17(3):500-514. doi: 10.1002/alz.12209. Epub 2020 Nov 20.
The presymptomatic phase of neurodegenerative disease can last many years, with sustained cognitive function despite progressive atrophy. We investigate this phenomenon in familial frontotemporal dementia (FTD).
We studied 121 presymptomatic FTD mutation carriers and 134 family members without mutations, using multivariate data-driven approach to link cognitive performance with both structural and functional magnetic resonance imaging. Atrophy and brain network connectivity were compared between groups, in relation to the time from expected symptom onset.
There were group differences in brain structure and function, in the absence of differences in cognitive performance. Specifically, we identified behaviorally relevant structural and functional network differences. Structure-function relationships were similar in both groups, but coupling between functional connectivity and cognition was stronger for carriers than for non-carriers, and increased with proximity to the expected onset of disease.
Our findings suggest that the maintenance of functional network connectivity enables carriers to maintain cognitive performance.
神经退行性疾病的无症状前阶段可能持续多年，尽管存在进行性萎缩，但认知功能仍持续。我们在家族性额颞叶痴呆（FTD）中对此现象进行了研究。
我们使用多变量数据驱动方法将认知表现与结构和功能磁共振成像联系起来，研究了 121 名有症状前 FTD 突变携带者和 134 名无突变的家族成员。我们比较了两组之间的萎缩和脑网络连通性，与预期症状发作时间有关。
尽管认知表现没有差异，但两组之间存在大脑结构和功能的差异。具体而言，我们确定了与行为相关的结构和功能网络差异。两组的结构-功能关系相似，但与认知的功能连接耦合在携带者中比非携带者更强，并且随着疾病预期发作的临近而增加。
我们的发现表明，功能网络连通性的维持使携带者能够保持认知表现。
