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Aim: Language lateralization with functional transcranial Doppler sonography (fTCD) and lexical word generation has been shown to have high concordance with the Wada test and functional magnetic resonance imaging in adults. We evaluated a nonlexical paradigm to determine language dominance in children. Method: In 23 right-handed children (12 females, 11 males; age range 6-11y; mean age 8y 4mo, SD 1y 7mo) and in 22 adolescents (14 females, 8 males; age range 12-18y; mean age 14y 8mo, SD 2y 5mo) cerebral blood flow velocity (CBFV) was measured in both middle cerebral arteries during picture description and in adolescents additionally during lexical word generation. For each individual/paradigm a lateralization index (LI; side difference in CBFV during mental activity) and its standard error of the mean (SEM; representing variability of the LI throughout task repetition) were computed. Results: Fourteen of 23 children (mean LI = 0.74, SD 4.22; SEM 1.05, SD 0.51) and 14 of 21 adolescents (LI = 2.35, SD 4.65; SEM 1.09, SD 0.61) showed left hemispheric dominance during picture description compared with 20 of 21 adolescents during word generation (LI = 3.72 SD 1.93; SEM 0.99, SD 0.41). Indicated by similarity in mean SEM, variability of the LI throughout task repetition did not differ between age groups or paradigms. Interpretation: Functional TCD proved to be well tolerated in children, with similar data quality as in adolescents. However, the picture description paradigm failed to show left hemispheric dominance in a substantial number of participants. This emphasizes the need to evaluate further paradigms for fTCD language lateralization in children.

Temporal processing of durations in the range of seconds or more is mediated by working-memory mechanisms whereas processing of brief durations in the range of milliseconds appears to be beyond cognitive control and modulated by dopaminergic activity in the basal ganglia. In the present study, the effects of the selective noradrenaline reuptake inhibitor reboxetine on temporal information processing were evaluated. In a double-blind crossover design, either placebo or 2 or 4 mg of reboxetine were administered to 24 healthy male volunteers. Performance on temporal discrimination of longer durations, as indicated by 75%-difference thresholds in relation to a 1,000-ms standard interval, was significantly improved by 2 mg of reboxetine as compared to placebo, whereas the improvement observed with the 4-mg dose just failed to reach statistical significance. There was, however, no effect of reboxetine on temporal discrimination of extremely brief durations, as indicated by threshold values in relation to a 50-ms standard interval. Findings provided additional evidence for the notion that temporal processing of durations in the range of seconds is based on working-memory processes including aspects of directed attention. In timing of brief durations in the range of milliseconds, however, noradrenergic activity did not seem to play a critical role.

Major depressive disorder (MDD) is frequently accompanied by sleep disturbance. Regarding diurnal preference (chronotype), sleep problems and low mood have been associated with evening orientation. Considering diurnal preference, we investigated subjective restorative value of sleep and actigraphy sleep parameters together with mood assessments twice a day, i.e. in the morning and evening, during weekdays and weekends in MDD psychiatric inpatients and healthy controls (HCs). The restorative value of sleep was higher during the weekend in HC, and bedtimes and risetimes were delayed during the weekend compared to weekdays in HC and MDD. Morning mood affected subjective sleep ratings in both groups, while association with symptom severity (BDI) in MDD remained insignificant. In HC, better evening mood was associated with later bedtimes. Regarding the chronotype in HC, evening orientation was associated with relatively low restorative value of sleep during weekdays, and morning orientation was associated with relatively higher actigraphy sleep efficiency during weekdays compared to weekend. In MDD, an association of evening orientation with later rise times could be observed, while no chronotype dependent effect emerged regarding the restorative value of sleep or sleep efficiency. Our results emphasize that research on sleep in MDD should incorporate weekdays as well as weekends, chronotype assessment, and measures of morning and evening mood, as these can be associated with ratings of the subjective restorative value of sleep (i.e. in our study, better morning mood was associated with higher restorative values), but also with behavioral sleep parameters (i.e. in our study, more positive evening mood was associated with later bedtimes). Potentially, the restorative value of sleep in MDD evening types can be improved by maintaining a regular sleep schedule, which needs to be investigated in an experimental design. [ABSTRACT FROM AUTHOR]

Chronobiology and chronobiological research deal with time-dependent physiological processes and behavioral correlates as well as their adaptation to environmental conditions. Chronobiological research is presently focused on the impact of circadian rhythms on human behavior. In the last three decades, chronobiology has established itself as an independent area of research evolving to an important field of clinical psychology and psychiatry. In this overview, the results of studies on the clinical importance of chronotypes are summarized. The main focus is on the role of chronotype in depressive disorders. [ABSTRACT FROM AUTHOR]

Objective SCN1 A encodes the alpha subunit of the voltage-gated sodium channel and plays a crucial role in several epilepsy syndromes. The common SCN1 A splice-site polymorphism rs3812718 ( IVS5 N+5 G> A) might contribute to the pathophysiology underlying genetic generalized epilepsies and is associated with electrophysiologic properties of the channel and the effect of sodium-channel blocking antiepileptic drugs. We assessed the effects of the rs3812718 genotype on cortical excitability at baseline and after administration of carbamazepine in order to investigate the mechanism of this association. Methods Paired-pulse transcranial magnetic stimulation ( TMS) was applied in 92 healthy volunteers with the homozygous genotypes AA or GG of rs3812718 at baseline and after application of 400 mg of carbamazepine or placebo in a double-blind, randomized, crossover design. Resting motor threshold ( RMT), short interval intracortical inhibition ( SICI), intracortical facilitation ( ICF), and cortical silent period ( CSP) were determined. Results At baseline there was no significant difference in any TMS parameter. Genotype GG was associated with a higher carbamazepine-induced increase in CSP duration as compared to AA (multivariate analysis of covariance [ MANCOVA], p = 0.013). An expected significant increase in RMT was genotype independent. Significance We found that the rs3812718 genotype modifies the effect of carbamazepine on CSP duration (mainly reflecting modulation of γ-aminobutyric acid ( GABA)ergic inhibition), but not on RMT (mainly reflecting modulation of voltage-gated sodium channels). This provides evidence that rs3812718 affects the pharmacoresponse to carbamazepine via an effect on GABAergic cortical interneurons. Our results also confirm that TMS is useful to investigate the effect of genetic variants on cortical excitability and pharmacoresponse. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the predictive value of intraoperative electro-corticography (ECoG) in patients with unilateral hippocampal sclerosis (HS) undergoing transsylvian selective amygdalohippocampectomy (sAHE). ECoG was recorded before and after resection in 22 patients with medication-resistant mesial temporal lobe epilepsy. The sAHE was performed, regardless of ECoG findings. ECoG findings recorded from the mesiobasal temporal lobe (MTL) and lateral temporal lobe (LTL) before and after the sAHE were correlated with seizure outcome 12 months later. Ten patients had right-sided and 12 left-sided HS. Average age was 37.1 years. Pre-resection spikes were restricted to the MTL in 11 patients and to the LTL in one. In three patients spikes were recorded from MTL and LTL and in seven no spikes were recorded before the resection. Fifteen patients (68%) remained completely seizure-free and 19 (86%) were in Engel's class I post-operatively. Patients with pre-resection spikes restricted to the MTL ( n=11) remained seizure-free more frequently (9/11, 82%) compared with other patients (6/11, 55%; P=0.36). Pre-resection ECoG may be helpful in the prediction of seizure outcome in patients undergoing sAHE for mesial temporal lobe epilepsy. A larger study including more than 100 patients is needed to determine the predictive value of ECoG in patients with mesial temporal lobe epilepsy. [ABSTRACT FROM AUTHOR]

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