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Background: The prevalence of binge drinking has risen in recent years. It is associated with a range of neurocognitive deficits among adolescents and young emerging adults who are especially vulnerable to alcohol use. Attention is an essential dimension of executive functioning and attentional disturbances may be associated with hazardous drinking. The aim of the study was to examine the oscillatory neural dynamics of attentional control during visual target detection in emerging young adults as a function of binge drinking.Method: In total, 51 first-year university students (18 ± 0.6 years) were assigned to light drinking ( n = 26), and binge drinking ( n = 25) groups based on their alcohol consumption patterns. A high-density magnetoencephalography signal was combined with structural magnetic resonance imaging in an anatomically constrained magnetoencephalography model to estimate event-related source power in a theta (4-7 Hz) frequency band. Phase-locked co-oscillations were further estimated between the principally activated regions during task performance.Results: Overall, the greatest event-related theta power was elicited by targets in the right inferior frontal cortex and it correlated with performance accuracy and selective attention scores. Binge drinkers exhibited lower theta power and dysregulated oscillatory synchrony to targets in the right inferior frontal cortex, which correlated with higher levels of alcohol consumption.Conclusions: These results confirm that a highly interactive network in the right inferior frontal cortex subserves attentional control, revealing the importance of theta oscillations and neural synchrony for attentional capture and contextual maintenance. Attenuation of theta power and synchronous interactions in binge drinkers may indicate early stages of suboptimal integrative processing in young, highly functioning binge drinkers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Behavioral studies suggest that alcohol intoxication impairs the speed and accuracy of word recognition and categorization, but alcohol's effects on the brain during verbal cognitive processing are not adequately understood. Using event-related potentials (ERP) and a word-recognition paradigm, this study investigated the effects of alcohol intoxication on prelexical, semantic, and mnemonic aspects of verbal processing. METHODS: Concurrent measures of ERPs and skin conductance responses were obtained in a word-repetition priming task and permitted a comparison of the effects of alcohol on the central and autonomic physiologic systems. Social drinkers participated in all four cells of the within-subjects balanced placebo design, in which the effects of alcohol and information as to the beverage content (expectancy) were manipulated. The average peak blood alcohol level peaked at 0.045%. RESULTS: None of the manipulations affected behavioral performance, and expectancy had no effect on any of the measures. In contrast, alcohol ingestion attenuated the temporoparietal N180, suggesting an impairment in prelexical pattern-recognition processes. Alcohol significantly increased the amplitude of N450 and the latency of P580, particularly on trials evoking sympathetic arousal as measured with skin conductance responses. CONCLUSIONS: Although behavioral measures were unaffected, ERPs showed that a moderately low alcohol dose affected verbal processing during both early, prelexical and late, semantic stages. Alcohol significantly increased the difficulty of semantic access and integration, as reflected in larger N450 amplitude and longer P580 latency. This effect was particularly prominent on arousal-related trials, suggesting that alcohol impairs processes that modulate cognitive functioning. The lack of an interaction between the factors of repetition and beverage suggests that a moderately low alcohol dose exerts these effects via the semantic and integration systems rather than via memory processes. [ABSTRACT FROM AUTHOR]

The patient described in the companion paper by Vignal, Chauvel, and Halgren (this issue) was studied with event related potentials (ERPs) recorded directly within the brain substance, as well as with neuropsychological tests before and after therapeutic cortectomy. Large ERPs were evoked in the prefrontal cortex to faces, as compared to sensory controls and words. The largest such ERPs were highly localised to the same right anterior inferior prefrontal site where direct electrical stimulation resulted in face hallucinations. Face-selective ERPs were also evoked in the right prefrontal sites that had shown projected activity during face hallucinations, and near the right anterior superior temporal sulcus. Selective responses began about 150msec after face onset. Words, but not faces or sensory controls, evoked large ERPs in distinct locations, mainly in the left hemisphere. A successful surgical therapy was performed by removing the cortex surrounding the right prefrontal site where face-selective responses were recorded and where face hallucinations were evoked by stimulation. This cortectomy resulted in a severe deficit in the recognition of emotional facial expressions, especially fear. No change was noted, however, in the recall of emotional words, or other tasks. The current results provide strong support for the early, specific, and sustained involvement of a multi-focal network in the right inferior fronto-temporal cortex in face-processing. [ABSTRACT FROM AUTHOR]

Nanostructured YAG:Ce3+ and Y2O3:Eu3+ were synthesized by low temperature (320°C) aerosol synthesis-LTAS and high temperature (900°C) aerosol synthesis-HTAS, respectively. The synthesis included aerosol generation from a nitrate precursor solution by an ultrasonic atomizer (1.3 MHz). The obtained aerosol was introduced into a tubular flow reactor, using air as the carrier gas, where successively, on a droplet level, evaporation/drying, precipitation and thermolysis occurred. The obtained powders were collected and thermally treated at different temperatures (900-1200°C). The phase development and the morphology were investigated by the X-ray powder diffraction method (XRPD) and scanning electron microscopy combined with energy dispersive spectrometry (SEM/EDS). Structural refinement was performed using the Rietveld method with the Fullprof and Koalariet programs. The average crystallite size for the Y2O3:Eu system was calculated using the Profit program. It was shown that 89 wt.% of Y3Ai5Oi2:Ce was obtained by annealing (1000°C/6 h) the as prepared, amorphous powder, synthesized by the low temperature aerosol method (LTAS). High temperature spray pyrolysis (HTAS) at 900°C led to the formation of the targeted cubic phase of Y2O3:Eu3+. The microstructural parameters of the asprepared samples of the Y2O3:Eu3+ system indicate the formation of nanostructures with crystallite size smallest than 20 nm. The substitution of luminescent centers (Ce3+, Eu3+) into a host lattice (YAG, Y2O3, respectively) was confirmed by changes in the crystal lattice parameters. Also, it was shown in both systems that good morphological characteristics (non-a­gglomerated, spherical, submicron particles) were obtained enabling improved luminescent characteristics.

Gadolinium and Ytrium oxides doped with europium (Gd2O3:Eu, Y2O3:Eu) have luminiscent properties. Such properties are improved with the use of nanostructured materials with spherical geometry and narrow particle size distribution. Besides, luminescent properties enhance with a homogeneous distribution of dopant centers in the host matrix material. In this paper the synthesis and characterization of gadolinium and yttrium doped with different proportions of Europium are shown. Nanostructured particles were synthesized through Spray Pyrolysis route in a tubular furnace at different temperatures, and subjected to different post-thermal treatments. Scanning electron microscopy (SEM-EDS), transmission electron microscopy (TEM) and X-ray diffractometry (XRD) were used for the morphological, chemical and structural characterization of the nanoparticles.Los óxidos de gadolinio y de ytrio dopados con europio (Gd2O3:Eu, Y2O3:Eu) presentan propiedades luminiscentes. Dichas propiedades mejoran con la utilización de materiales nanoestructurados, con geometría esférica y estrecha distribución de tamaño de partícula. Además, las propiedades luminiscentes son favorecidas cuando se tiene una distribución homogénea de los centros dopantes en la matriz del material anfitrión. En este estudio se presenta la síntesis y caracterización de óxidos de gadolinio y de ytrio dopados con diferentes proporciones de Eu. Se sintetizaron partículas nanoestructuradas mediante la técnica de Spray Pirólisis en un horno tubular a distintas temperaturas, las cuales fueron sometidas posteriormente a diferentes tratamientos isotérmicos. La caracterización morfológica, química y estructural de las nanopartículas se realizó por microscopia electrónica de barrido (MEB-EDS), microscopía electrónica de transmisión (MET) y difracción de rayos-X (DRX).