Persistent deficits of visual recall in Kleine-Levin syndrome.

Kleine-Levin syndrome (KLS) is commonly described as a self-limiting disorder exhibiting episodes of hypersomnia and psychiatric symptoms but without any enduring disabilities. Recently, some authors have reported persistent or even progressive memory deficits associated with the disorder. Nevertheless, literature about cognitive disturbances in KLS is rare. Our report describes a patient with deficits of visual and verbal recall after remission of an episode, as well as selective deficits of visual recall 6 months later. Neuropsychological testing is necessary in all patients with KLS to further characterize the profile and impact of associated cognitive deficits.

COMT Val 158 Met polymorphism is associated with cognitive flexibility in a signal discrimination task in schizophrenia.

BACKGROUND: Associations between the well-known functional single nucleotide polymorphism Val (158)Met in the gene encoding catechol- O-methyltransferase (COMT) and cognitive do-mains affected in schizophrenia are inconsistent regarding directionality and specific impact and call for a more fundamental cognitive endophenotype. Recent studies suggest that the COMT genotype contributes to cognitive flexibility, a fundamental cognitive ability that potentially influences an individual's performance in a variety of other neurocognitive tasks. METHODS: We investigated the association between COMT Val (158)Met genotype and cognitive flexibility as assessed by signal discrimination in the Continuous Performance Test - Identical Pairs version in a cohort of 111 German schizophrenic patients. RESULTS: COMT genotype was significantly associated with signal discrimination index d' in schizophrenia. The Val/Val genotype was associated with the highest and the Met/Met genotype with the lowest scores; heterozygous individuals displayed an intermediate performance. CONCLUSIONS: Our data suggest that allelic variation at the COMT Val (158)Met locus may influence signal discrimination capacity in schizophrenia and confirm that Val loading, probably due to decreased prefrontal dopamine availability, is associated with greater cognitive flexibility, which in turn may influence other cognitive measures that have been associated with COMT to date.

Electroconvulsive monotherapy in confusion psychosis: a potential standard regimen?

We report on the successful use of continuation electroconvulsive therapy (ECT) as prophylactic treatment of relapse in a case of confusion psychosis. The 20-year-old patient exacerbated in an almost annual rhythm and had been characterized as pharmacologically treatment-resistant since he failed to respond to any psychopharmacological therapy including sufficient clozapine as well as mood-stabilizing and sedating pharmacological treatments. After the diagnosis of confusion psychosis, the patient received ECT as monotherapy and showed a marked reduction of symptoms. Continuation ECT was then conducted for 7 months after the patient was discharged from hospital. Two years later, our patient is still in remission while continuation ECT has been tapered; no prophylactic psychotropic medication was prescribed in the last 2 years. Implications of this case on the therapy of confusion psychosis as well as on the diagnostic classification of confusion psychosis within our current systems are discussed.

P300 is enhanced in responders to vagus nerve stimulation for treatment of major depressive disorder.

BACKGROUND: Vagus nerve stimulation (VNS) is a new therapy option for treatment of otherwise therapy-refractory major depressive disorder. However, the mechanism of central nervous action is poorly understood. Electroencephalographic (EEG) studies may be of interest since chronic peripheral current application to the vagus nerve may exert lasting neurophysiologically detectable effects on central electrical activity. In an exploratory study, we investigated the effects of VNS on auditory event-related potentials (ERP). METHODS: Thirteen depressive patients (mean Hamilton depression score (HAMD) at baseline=24.2) receiving VNS were investigated prior to implantation and 10 weeks after standard cycling VNS. Stimulation intensity was 0.94+/-0.46 mA, pulse width 0.250 mus, and frequency 20 Hz. 1 h prior to follow-up investigation, VNS was turned off. Auditory ERP were elicited using a standard auditory oddball paradigm and were recorded with 29-channel EEG. RESULTS: Post VNS, grand averages of the auditory ERP did not show significant differences as compared to baseline recording. However, differential effects were found when separating ERP of responders (N=5, mean HAMD post VNS=8.8) and non-responders (N=8, mean HAMD post VNS=22.4). In VNS responders only, P300 at midline electrodes Fz and Cz was significantly increased and correlated with HAMD scores. CONCLUSION: Auditory ERP seem to provide a useful tool for investigating VNS-induced changes concerning information processing in major depressive disorder. In our sample, enhancement of P300 distinguished VNS responders from non-responders 10 weeks after therapy onset. Our findings may be relevant for the understanding of both neurophysiological mechanism of action of VNS and pathophysiology of depression.

Electroconvulsive monotherapy in the treatment of acute confusion psychosis. A case report.

This report focuses on the successful treatment of a most acute case of confusion psychosis according to the concept of Karl Leonhard. The 18-year-old patient was hospitalized three times before the current episode and his case has been characterized as pharmacologically treatment-resistant psychosis since he failed to respond to any psychopharmacological therapy including sufficient clozapine medication. In the patient's history, typical and atypical antipsychotic as well as mood-stabilizing and sedating pharmacological treatments have been conducted. However, only adverse effects could be observed. When receiving electroconvulsive monotherapy (ECT), the patient showed a marked reduction of symptoms while experiencing no adverse effects. The implications of this finding are discussed with regard to Leonhard's diagnostic system.