is a typical symptom of major depressive disorders which occurs usually after falling asleep normally, waking up and then being unable to fall back asleep.

MIDDLE INSOMNIA: "The process of falling asleep but then waking up soon after is named middle insomnia."
Cite this page: N., Pam M.S., "MIDDLE INSOMNIA," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/middle-insomnia/ (accessed May 8, 2021).