The Role of Hippocampal Interneuron Migration in Neurodevelopmental Disorders: A Systematic Review

Hippocampal abnormalities are frequently associated with neurodevelopmental disorders as interneurons are crucial in establishing the network connectivity of neurons. This systematic review analyzed primary literature with a focus on aberrant hippocampal interneuron migration as an etiology for neurodevelopmental disorders, summarizing the current field and identifying gaps that require further understanding. We adhered to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines to perform a comprehensive review of the existing research on GABAergic, parvalbumin, somatostatin, cholecystokinin, neuropeptide Y, calbindin, and calretinin interneuron migration in the hippocampus. Three blocks of search terms were used to extract 1459 papers from the PubMed, PsycINFO, and Web of Science databases. Following screening, we identified 29 articles which met the inclusion/exclusion criteria for the study. There is evidence that interneurons are affected in many neurodevelopmental conditions, with distinct regional and subtype-specific differences. This systematic review has determined that there is a clear association between deficits in interneuron migration to the hippocampus and the presentation of neurodevelopmental disorders. The review highlights a significant lack of sex differences considered in the field, as well as a paucity of data for many specific neurodevelopmental conditions.