FC21: Loose functional connectivity within the striatum in behavioral variant frontotemporal dementia

Objective:Previous studies have reported that the structure and function of the striatum are important in bvFTD, and the striatum can be divided into more subregions. Changes within brain regions has recently attracted increasing attention, but most studies have explored the relationship between the striatum and other brain regions. Therefore, the aim of this study was to explore the changes in the intra-striatal resting-state functional connectivity (RSFC).Methods:We acquired fMRI data from 26 bvFTD patients and 36 healthy controls. The Human Brainnetome Atlas was used to define the spatial extent of the striatum and delineate its subregions. Intra- and extra-striatal FC values were then calculated for each individual and compared between bvFTD and control groups.Results:Compared to healthy controls, bvFTD showed decreased intra-striatal FC. Both intra-hemispheric and inter-hemispheric functional connectivity were compromised. There was also a gradient reduction in terms of the functional connectivity within striatum: the left dorsolateral putamen showed most decrease and the left ventral caudate exhibited the least (Fig 1). The extra-striatal FC between striatum and the insula was also decreased.Conclusion:The loose intra-striatal functional connectivity may underly the neural substrate of bvFTD.