Agrypnia excitata.

The concept of Agrypnia excitata (AE) was originally proposed as a concept deriving from the clinical and anatomo-pathological observations obtained in three different diseases, Fatal familial insomnia (FFI), Delirium tremens (DT), and Morvan syndrome (MS). Agrypnia refers to a condition of severely reduced or absent sleep due to organic disorders. Excitata refers to the association of agrypnia with generalized motor and autonomic hyperactivation. AE is a syndrome that has been claimed to relate to a dysfunction in the thalamo-limbic circuits that govern sleep-wake cycles and autonomic activities.