A critical role in place learning has been attributed to place cells within the cornu ammonis 1 (CA1) sector of the hippocampus in rodents. The role of CA1 cells in the human hippocampus with regard to place learning remains elusive. Using a virtual Morris water maze, we investigated patients with acute transient global amnesia (TGA), a rare self-limiting dysfunction of the hippocampal system. Fourteen individuals with selective and focal lesions in the CA1 sector of the hippocampus showed a profound impairment in place learning. The size of the lesions and the duration of the TGA correlated with the deficit in the performance.

Our data demonstrate improvements in memory functions, executive functions and psychomotor abilities after a single dialysis session, pointing to a reversible component of low cognitive performance in CKD5D.

Abstract. We present a new algorithm for k-layer straightline crossing minimization which is based on sifting that is a heuristic for dynamic reordering of decision diagrams used during logic synthesis and formal verification of logic circuits. The experiments prove sifting to be very efficient. In particular it outperforms the traditional layer by layer sweep based heuristics known from literature by far when applied to k-layered graphs with k ≥ 3.

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The results confirmed those found by Birner et al.. In order to enhance compliance patients should undergo psychoeducation with respect to illness behaviour and specific history taking with respect to emotional disorders prior to dystonia.

To document specific learning mechanisms in patients with Parkinson's disease (PD) with and without impulse control disorder (ICD). Thirty-two PD patients receiving dopamine replacement therapy (DRT) were investigated. Sixteen were diagnosed with ICD (ICD ) and 16 PD patients matched for levodopa equivalence dosage, and DRT duration and severity of disease did not show impulsive behavior (non-ICD). Short-term learning of inhibitory control was assessed by an experimental procedure which was intended to mimic everyday life. Correct inhibition especially, had to be learned without reward (passive avoidance), and the failure to inhibit a response was punished (punishment learning). Results were compared to 16 healthy controls (HC) matched for age and sex. In ICD patients within-session learning of non-rewarded inhibition was at chance levels. Whereas healthy controls rapidly developed behavioral inhibition, non-ICD patients were also significantly impaired compared to HC, but gradually developed some degree of control. Both patient groups showed significantly decreased learning if the failure to withhold a response was punished. PD patients receiving DRT show impaired ability to acquire both punishment learning and passive avoidance learning, irrespective of whether or not ICD was developed. In ICD PD patients, behavioral inhibition is nearly absent. Results demonstrate that by means of subtle learning paradigms it is possible to identify PD-DRT patients who show subtle alterations of punishment learning. This may be a behavioral measure for the identification of PD patients who are prone to develop ICD if DRT is continued.

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