“Development of a Short Sleeper Phenotype After Third Ventriculostomy in a Patient With Ependymal Cysts”, Katharina Seystahl, Helen Könnecke, Oguzkan Sürücü, Christian R. Baumann, Rositsa Poryazova2014 (, , ; similar)⁠:

A naturally short sleeper phenotype with a sleep need of less than 6 hours without negative impact on health or performance is rare.

We present a case of an acquired short sleeper phenotype after third ventriculostomy. A 59-year-old patient suffering from chronic hydrocephalus reported an average of 7–8 hours of nocturnal sleep. After surgical intervention, the patient noted a strikingly reduced sleep need of 4–5 hours without consequent fatigue or excessive daytime sleepiness, but with good daytime performance and well-balanced mood. Short sleep per 24 hours was confirmed by actigraphy. Postoperative imaging revealed decreased pressure around the anterior third ventricle.

The temporal link between development of a short sleeper phenotype and third ventriculostomy is striking. This might suggest that individual short sleep need is not only determined by genetics but can also be induced by external factors.