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Event-related potential (ERP) analysis associated with semantic priming is traditionally based on the comparison between experimental conditions of the mean amplitude values, which are within the range of the N400 component latency. In this study, we used a complete ERP dataset to examine whether middle- and long-latency components are modulated by semantic priming in school-age children. ERPs were recorded while normal children read pairs of words and decided whether the second word of the pair belonged to the same semantic category as the first word. We used nonparametric multivariate permutation analysis to compare whole ERP amplitude values between related and unrelated word pairs. We also obtained ERPs from a sample of children with poor reading skills (reading disabled children) to evaluate the effect of semantic priming in a population with known information retrieval failures. We found larger P200 amplitudes for responses to related word pairs compared to unrelated word pairs and larger N400 amplitudes for responses to unrelated word pairs compared to related word pairs in normal children. In contrast, children with reading disabilities did not exhibit any significant differences regarding either of these components. Thus, changes in the topographical distribution of ERP components over time might reflect the activation of several brain structures. These results suggest that semantic priming is a process that is not only associated with the N400 component.

The objective of this study was to find changes in EEG power during emotions of positive, negative valence as compared with neutral condition, evoked by the International Affective Pictures. The subjects were 36 young, healthy male university students. Power values were calculated from 21 referential derivations. Statistical analyses were carried out with Repeated ANOVA Measures having 3 conditions (positive, negative and neutral picture presentations), four bands and the above mentioned 21 leads) . Fisher´s LSD post hoc test revealed the topography of the significant differences. The objective of the study was to see whether right hemisphere is preferential for emotions or there is a hemispheric frontal alpha decrease according to the valence of the emotions. Our results show that most differences between emotional conditions occurred in the delta and theta bands band at frontopolar, frontal, temporal, parietal and occipital leads, without preference for right hemisphere participation. Right, left and midline leads both show significant differences between emotional conditions. In the alpha and beta bands very few significant differences between emotional states were observed, none of them at frontal areas. Alpha and beta activity revealed only negligible differences between pleasant and unpleasant conditions and the areas where activation occurred had no relation with the valence of the stimuli. The results obtained for relative power (RP) values were significant only in the delta band. Based on our results we can conclude that data do not show a defined pattern of activity, but various areas and both hemispheres respond to emotions. These findings are in accordance with previous reports of FMRI studies.

"In the present study, we propose to explore the Event-Related Potentials (ERP) components elicited in reading disabled (RD) and normal readers (NR) children by phonological and se - mantic processes using an auditory sentence comprehension task, that manipulate both pho - nological and semantic expectancies. Reading deficiencies in both these processes have been demonstrated in RD children, thus similar problems might also be expected for oral language in these children. Twenty-two male children (9-12 years old) with normal IQ, were classified by Neuropsychological Battery for Reading Disabilities into two groups: Normal Readers (NR, n=11) and Reading Disabled (RD, n=11). ERPs were recorded from 19 derivations of the I.S. 10- 20. Children were presented with spoken sentences that ended with a word that was either (a) semantically congruent, and phonologically expected, (b) semantically incongruent, but 74 Journal of Behavior, Health & Social Issues vol. 4 num. 2 nov -2012 / apr -2013 Rodríguez-Camacho, Bravo-Campos, Prieto-Corona, Marosi-Holczberger, Silva-Pereyra & Yáñez-Téllez ral Management of Special Education (from the Public Education Ministry) estimates that the prevalence of LD in this country is between 6 and 7% of the general school-age population (Fletcher & Kaufman, 1995). Within the population of children diagno - sed with LD, specific reading disability (RD) is beginning with the same initial phonemes as the congruent completion, or (c) semantically incongruent, and phonologically unexpected. For each type of sentence, ERP were analyzed in two time windows: early time window (330-430 ms) related to phonological processing, as well as a later N400 window (515-615 ms) that would reflect the semantic processing. In both groups, the three types of sentences elicited a negative waveform with an onset at 200 ms that lasted until approximately 900 ms. This negative waveform had greater amplitude in response to semantically incongruent, compared to semantically congruent sentences. Results revealed a probably anomalous phonological processing in RD children, reflected by a greater ERP res - ponse to expected, than to unexpected, words in a given sentential context. However, both the N400 responses related to semantic processing, and the behavioral responses related to the correctness of sentences, were comparable between RD and NR children."

Desde este trabajo se pretende dar cuenta del deterioro de las condiciones de vida existentes de la población y de la fragmentación socio-espacial, a través de la aplicación de un Índice-resumen de Calidad de Vida para el aglomerado urbano de Bahía Blanca. Con este propósito se analizan las siguientes dimensiones: vivienda, educación, salud y ambiente, así como la combinación de las variables que participan en la configuración socio-espacial. De este modo, la investigación demuestra las fragmentaciones y diferenciación de áreas, plasmadas en profundas desigualdades en cuanto a condiciones habitacionales y disponibilidad de servicios públicos urbanos. La fuente de información para la medición de las diferencias de calidad de vida de la población bahiense corresponde a los datos del Censo 2001 en el nivel de radios censales y su tratamiento se realizó mediante la aplicación de REDATAM+SP. Además, se utilizó para la representación cartográfica un Sistema de Información Geográfica, lo que permitió un análisis intraurbano más detallado., This paper aims at accounting both for the deterioration of the living conditions of the population as well as for the socio-spatial fragmentation of the urban conglomerate of Bahía Blanca by means of the application of a Life Quality summary-index. The following dimensions are analyzed with this purpose in mind: housing, education, health and environment, as well as the combination of the variables which are part of the socio-spatial configuration. Thus, the research shows the areas? fragmentations and differentiation which are invested in profound inequalities as regards living conditions and the availability of urban utilities. The information for measuring the differences in quality of life of the population of Bahía Blanca comes from the data obtained from the 2001 Census on the level of census radius; and its treatment was carried out through the application of REDATAM+SP. Moreover, a Geographic Information System was used for the cartographic representation, which allowed for a more detailed intra-urban analysis., Departamento de Geografía