Short-term memory dysfunction in Kleine-Levin syndrome

Abstract

It is striking that all the cases investigated showed short-term memory dysfunction. One patient who had recovered from paroxysmal symptoms (hypersomnia attacks and bulimia) 6 years earlier showed progress in the short-term memory dysfunction. A pathologic condition in the temporal lobes may be suspected in Kleine-Levin syndrome.

Persistent deficits of visual recall in Kleine–Levin syndrome

“…6 Persisting hypoperfusion in fronto-temporal regions even during asymptomatic intervals could be replicated by another group 4 leading to the hypothesis that patients with KLS may exhibit subtle or even progressive cognitive disturbances resulting from neocortical damage of fronto-temporal regions increasing proportionally with the number of episodes. 4,7,8 In line with this hypothesis, our patient showed selective deficits of verbal and visual recall several days after resolution of symptoms, and deficits of visual recall persisted even 6 months later.…”

“…[8][9][10] Recently, deficits of visual and verbal short-term memory during remission were reported in four patients with KLS. 6,7 One patient re-tested 6 years after spontaneous recovery showed pronounced reduction in short-term memory capacity along with persisting hypoperfusion of left temporal regions. 6 Persisting hypoperfusion in fronto-temporal regions even during asymptomatic intervals could be replicated by another group 4 leading to the hypothesis that patients with KLS may exhibit subtle or even progressive cognitive disturbances resulting from neocortical damage of fronto-temporal regions increasing proportionally with the number of episodes.…”

New hypothesis on pontine–frontal eye field connectivity in Kleine–Levin syndrome

“…No other regions were significantly connected to the dorsal pons seed region. In the current study, we found reduced connectivity between the dorsal pons and the frontal eye field in a group of asymptomatic KLS patients with previously reported working memory deficits (Landtblom et al, 2003;Engström et al, 2009;Engström et al, 2013).…”

PANDAS and Comorbid Kleine–Levin Syndrome

“…Computed tomography (CT) and magnetic resonance imaging (MRI) of the brain are typically normal in patients with KLS (Servan et al 1993;Poryazova et al 2007;Huang et al 2012b), and polysomnography tends to display impairment of slow wave sleep and rapid eye movement sleep at symptom onset (Huang et al 2008). Studies of the long-term effects of KLS are limited, but short-term memory dysfunction, academic decline, and auditoryverbal attention deficits have been observed even during periods of remission (Fontenelle et al 2000;Landtblom et al 2003).…”