Age of onset (years) | 3–8 | Any age | After 50 | Usually 3–6 |
Course | Tends to disappear | Usually increases | Rare spontaneous remission | Variable |
Episodes per night | Usually one | Usually several | One to several | One to several |
Occurrence during the night | First third | Any time | Last third | Last third |
Episode duration | 1–30 min | Seconds–3 min | 1–2 min | Seconds–minutes |
Motor pattern | Variable: sitting up, pulling at bed clothes, speaking, sleepwalking, screaming, usually with eyes opening | Highly stereotyped: complex body movements, kicking or cycling of limbs, rocking body movements, asymmetric tonic/dystonic posturing | Finger twitching or flexing to complex dream enactment behaviour | Most commonly absent, but rarely can consist of simple movements with preserved REM atonia |
Awareness if awakened | Usually absent | Variable | Usually present | Usually present |
Recall | Usually absent | Variable | Usually present, sometimes with vivid detail | Usually present, sometimes with vivid detail |
PSG features | Cyclic alternating pattern, hypersynchronous delta activity, possible periodic limb movements (confusional arousals/sleepwalking), increased autonomic function (sleep terrors) | Epileptiform features on sleep EEG | REM sleep without atonia | Variable: may be normal, may display reduced sleep efficiency and increased wakefulness, may identify sleep disrupting pathology |