The causal effect of insomnia on the hippocampal volume and hippocampal plasticity

Motivation: The causal relationship between the sleep-related traits and the plasticity of subcortical brain volumes remains unclear. Goal(s): This study aims to explore the causal relationship between two sleep-related traits (i.e., sleep duration and insomnia) and subcortical volumes. Approach: Two-sample Mendelian randomization (MR) analysisResults: We found a significant causal effect of insomnia but not sleep duration on the hippocampal volume. Moreover, insomnia showed significant causal influence on the structural plasticity of the hippocampus, which may associated with the rates of hippocampal atrophy. Impact: The causal effect of insomnia on the hippocampal volume and plasticity may explain the adverse effect of insomnia on memory and may offer new evidence which could push the exploration of sleep management to delay the course of neurodegenerative diseases.