TSPO and neurodegenerative disease: Given TSPO’s multiple putative physiological functions, it is entirely possible that different mechanisms are at play in different diseases, and the mechanisms behind changes in TSPO expression in the context of ASD (and schizophrenia) are likely different from those underlying TSPO expression changes in a neurodegenerative disease, such as amyotrophic lateral sclerosis (ALS) [33, 34, 40] or Alzheimer’s disease [58], where increases are observed.