Clinical Neuroscience

[Synchronized, oscillatory brain activity in visual perception]

BRAUNITZER Gábor

SEPTEMBER 30, 2008

Clinical Neuroscience - 2008;61(09-10)

[The present study investigates one of the most promising developments of the brain-mind question, namely the possible links between synchronized oscillatory brain activity and certain (visual) perceptual processes. Through a review of the relevant literature, the author introduces the reader to the most important theories of coherent perception (’binding‘), and makes an attempt to show how synchronization of EEG-registrable oscillatory activities from various frequency bands might explain binding. Finally, a number of clinical problems are also mentioned, regarding which the presented theoretical framework might deserve further consideration.]

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Clinical Neuroscience

[Hungarian Society of Neurology and Psychiatry]

VÉCSEI László

Clinical Neuroscience

[Antiepileptic drugs as mood stabilizers: what did we learn from the epileptology?]

RAJNA Péter

[Author summarizes the practical aspects of psychiatric application of mood stabilizing antiepileptic drugs. He observes how to transfer experiences taken from the “epileptological” practice into the psychiatric care of bipolar patients. He shortly demonstrates the relevant information on the mechanisms of action, controversies and possible clinical effects influenced by the seizure inhibiting effect of the concerning molecules. By the opinion of the author the clinical importance of pharmacokinetic parameters are underestimated in the psychiatric practice. Therefore - as an original approach in the literature - he summarizes the detailed clinical indications of serum level measurements of antiepileptic drugs applied in psychiatry as mood stabilizers. The therapeutic experiences in epilepsy added a lot of practices for the most effective dosing, building, tapering and exchange of the mood stabilizer antiepileptics. Drug interactions (appear among the psychotropic drugs or with the commonly used medicines). As in any chronic therapies the main condition of patient's compliance is the lacking or very mild presence of the applied therapy. The paper discusses the most frequently occurring and drug-specific side effects in table forms. Using the term of “relative therapeutic potential” the need of balance between the efficacy (influenced by the choice and dosing) and the tolerance are pointed. Rules of application can change significantly in special populations like in pregnancy, obesity, chronic diseases or in chronic comorbide states and in case of polytherapy. As for the special therapeutic effects, the experiences are not completed even in group of antiepileptics: we have larger and more favorable knowledge on the traditional drugs (carbamazepine and valproates) and on lamotrigine (from the newer generation) but promising but not enough information exists on the newest antiepileptic molecules. Further targeted studies are needed for the identification and positioning of antiepileptic drugs in the palette of mood stabilizing pharmacotherapy and for the definition of evidence based, individually tailored and lifelong applied highly effective combinations of the mood stabilizing pharmacotherapy containing antiepileptic agents.]

Clinical Neuroscience

[Editorial comment]

RAJNA Péter

Clinical Neuroscience

[Paraneoplastic chronic demyelinating neuropathy and lambert-eaton myasthenic syndrome associated with multiple anti-neural antibodies and small-cell lung cancer]

RÓZSA Csilla, VINCENT Angela, ARÁNYI Zsuzsanna, KOVÁCS G. Gábor, KOMOLY Sámuel, ILLÉS Zsolt

[Lambert-Eaton myasthenic syndrome (LEMS) developed in a patient with presumed chronic inflammatory demyelinating polyneuropathy (CIDP) and negative chest CT. Since antibodies against both Hu and voltage-gated calcium channel (VGCC) were detected, repeated chest CT was performed, which eventually showed a pulmonary mass lesion. Biopsy revealed small cell lung cancer (SCLC) indicating the importance of repeated chest CT in LEMS even when an existing autoimmune-like disease and negative CT may suggest an autoimmune origin. This is the first report of paraneoplastic CIDP and LEMS associated with anti-Hu, anti-VGCC and SCLC.]

Clinical Neuroscience

[European Association of Young Neurologists and Trainees]

SZTRIHA László

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Clinical Neuroscience

[Spectral, phase-synchronization, and graph theoretical EEG changes related to mental arithmetics]

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[During mental arithmetic operations working memory playsan important role, but there are only few studies in which anattempt was made to separate this effect from the process ofarithmetics per se. In this study the effects of arithmetic onthe EEG of young adults (14 participants, six of themwomen, mean age 21.57 years, SD: 2.62) was investigatedduring a subtraction task in the θ(4-8 Hz) frequency band.Besides the power density spectrum analysis phasesynchrony based on recently developed graph theoreticalmethods were used and strength of local connections (clustercoefficient; C) and global interconnectedness of network(characteristic path length; L) were determined. Before thearithmetic task passive viewing (control situation) and anumber recognition paradigms were used. During the arith-metic task compared to the control situation significantlyincreasing phase synchrony and C values were found. L wassignificantly shorter (F(2, 26)=818.77, p<0.0001) only dur-ing the arithmetic task: this fact and the former two resultsimply that the network topology shifted towards the “smallworld” direction. Our findings concerning regionaldifferences confirm those reported earlier in the literature:compared to the control condition significant task-relatedincrease was found in C values in the parietal areas [moreexplicitly in the left side, (F(1, 13)=7.2020, p=0.0188)],which probably corresponds to stronger local connectionsand more synchronized (sub)networks. During the task con-dition significantly increased θband power; (F(1,13)=7.9708, p=0.0144) and decreased L values werefound in the left frontal region compared to the right side(F(1, 13)=6.0734, p=0.0284), which can also be interpret-ed as an indicator of optimized network topology ofinformation processing.]

Clinical Neuroscience

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Clinical Neuroscience

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