Clinical Neuroscience

[The role of sleep in the implicit learning processes]

CSÁBI Eszter, NÉMETH Dezsõ

JANUARY 30, 2014

Clinical Neuroscience - 2014;67(01-02)

[The role of sleep in different memory processes is debated. Probably it plays an active role in the memory consolidation or possibly it prevents forgetting by protecting against interference or it makes the memory performance more efficient by facilitating the forgetting. The beneficial effect of sleep in explicit memory is well demonstrated, while the role of sleep in implicit mechanisms has not been comprehensively characterized so far. There are several factors which affect the appearance of sleep effect, such as the structure, the length and the complexity of sequence being used, the awareness of the sequence, the length of the learning blocks and the offline period. Besides the classical sleep deprivation methods with healthy participants, examining patients with sleep disorders could be a new method of the investigation of the sleep effect which enables us to enrich our knowledge not only about the sleep-dependent memory consolidation but also the cognitive dysfunction related to sleep pathologies. This new line of research can help the development of more effective rehabilitation programs.]



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Clinical Neuroscience

[Clinical studies with levodopa/carbidopa intestinal gel]


[The motor complications in advanced Parkinson’s disease may interfere with the quality of life. To overcome this disability, a jejunal levodopa pump was developed. In this review we have summarized the published clinical data with this method.]

Clinical Neuroscience


Clinical Neuroscience

[Multiple disruption of the body representation in neglect]


[Background and purpose - Neglect related to the body has many symptoms. We suggest that the various symptoms might be associated with the injuries of different cognitive functions referring to the body, which are caused by lesions of different brain areas. Therefore we investigated the injuries of two functions in a group of patients with neglect (N=10) contrary to patients without neglect (N=10) and healthy controls (N=10). These functions are: perception of body location in external space and the perception of body shape. Methods - We applied a novel method (Body Portraying Method), which is suitable for measuring subjective perception of both body location and body shape. Results - 1. Patients with left neglect perceived their bodies with a significant right shift compared to their real body position. In contrast to this, patients without neglect and healthy controls tended to shift the subjective location of their body to the left. 2. Patients with neglect perceived the shape of their bodies significantly more distorted than both patients without neglect and healthy controls. 3. In case of eight patients with neglect, the symptom of shifted body location to the right and the symptom of body shape distortion appeared together. However, injuries of these two functions dissociated in case of two neglect patients. Conclusions - Both the perception of body location in external space and the perception of body shape might become distorted in neglect. Furthermore, the dissociation of these symptoms supports our suggestion, that they might be associated with the injuries of different functions referring to the body. This result has practical issues as well. At the end of the study we discuss the necessity of appropriate tailored physiotherapy (fitted to the injured function) in the rehabilitation of patients with neglect.]

Clinical Neuroscience

[Dostoyevsky’s epilepsy in the light of recent neurobiological data]

TÉNYI Dalma, RAJNA Péter, JANSZKY József, HORVÁTH Zsuzsanna, TÉNYI Tamás, GYIMESI Csilla

[Background and purpose -Since the 1960s several theories have developed on the epilepsy of Fyodor Mikhailovich Dostoyevsky. Probably the most exciting and still actual question might be the subject of the „ecstatic aura”, he described in his novels based on his own experiences. During this extremely rare seizure onset the patients experience a strong sense of happiness, harmony and wholeness. The symptomatogenic zone of ecstatic seizures were considered to be of temporal lobe origin for a long time. Lately though this theory seems to be questioned based on the results of SPECT and deep brain EEG monitoring techniques in addition to the enrichment of our knowledge concerning the function of the insular cortex. Methods - Literary and scientific overview on the subject of Dostoyevsky’s epilepsy, with special concern to his ecstatic seizures. Results and conclusion - According to new electrophysiology and imaging techniques ecstatic seizures - including the seizure onset of Dostoyevsky - could rather be connected to the insular cortex.]

Clinical Neuroscience

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BÓDIZS Róbert, GOMBOS Ferenc, SZŐCS Katalin, RÉTHELYI M. János, GERVÁN Patrícia, KOVÁCS Ilona

[Background and purpose - Reports on twin pairs concordant and discordant for Williams syndrome were published before, but no study unravelled sleep physiology in these cases yet. We aim to fill this gap by analyzing sleep records of a twin pair discordant for Williams syndrome extending our focus on presleep wakefulness and sleep spindling. Methods - We performed multiplex ligation-dependent probe amplification of the 7q11.23 region of a 17 years old dizygotic opposite-sex twin pair discordant for Williams syndrome. Polysomnography of laboratory sleep at this age was analyzed and followed-up after 1.5 years by ambulatory polysomnography. Sleep stages scoring, EEG power spectra and sleep spindle analyses were carried out. Results - The twin brother showed reduced levels of amplification for all of the probes in the 7q11.23 region indicating a typical deletion spanning at least 1.038 Mb between FKBP6 and CLIP2. The results of the twin sister showed normal copy numbers in the investigated region. Lower sleep times and efficiencies, as well as higher slow wave sleep percents of the twin brother were evident during both recordings. Roughly equal NREM, Stage 2 and REM sleep percents were found. EEG analyses revealed state and derivation- independent decreases in α power, lack of an α spectral peak in presleep wakefulness, as well as higher NREM sleep σ peak frequency in the twin brother. Faster sleep spindles with lower amplitude and shorter duration characterized the records of the twin brother. Spectra show a striking reliability and correspondence between the two situations (laboratory vs. home records). Conclusion - Alterations in sleep and specific neural oscillations including the α/σ waves are inherent aspects of Williams syndrome.]

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Clinical Neuroscience

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