An event-related potential study on the interaction between lighting level and stimulus spatial location

Due to heterogeneous photoreceptor distribution, spatial location of stimulation is crucial to study visual brain activity in different light environments. This unexplored issue was studied through occipital event-related potentials (ERPs) recorded from 40 participants in response to discrete visual stimuli presented at different locations and in two environmental light conditions, low mesopic (L, 0.03 lux) and high mesopic (H, 6.5 lux), characterized by a differential photoreceptor activity balance: rod > cone and rod < cone, respectively. Stimuli, which were exactly the same in L and H, consisted of squares presented at fixation, at the vertical periphery (above or below fixation) or at the horizontal periphery (left or right). Analyses showed that occipital ERPs presented important L vs. H differences in the 100 to 450 ms window, which were significantly modulated by spatial location of stimulation: differences were greater in response to peripheral stimuli than to stimuli presented at fixation. Moreover, in the former case, significance of L vs. H differences was even stronger in response to stimuli presented at the horizontal than at the vertical periphery. These low vs. high mesopic differences may be explained by photoreceptor activation and their retinal distribution, and confirm that ERPs discriminate between rod– and cone-originated visual processingThis work was supported by the grant PSI2014-54853-P and PSI2012-37090 from the Ministerio de Economía y Competitividad of Spain (MINECO

Affective neuroscience of ADHD: current data and future directions

Universidad de MálagaEl trastorno por déficit de atención con hiperactividad (TDAH) es un trastorno de origen neurobiológico complejo y heterogéneo que se caracteriza no sólo por sus disfunciones cognitivas sino también por la existencia de importantes alteraciones afectivas, tanto motivacionales como emocionales. Sin embargo, los correlatos neurobiológicos que subyacen a las disfunciones afectivas del TDAH apenas han sido explorados, en comparación con la extensa investigación llevada a cabo sobre los mecanismos neurales implicados en sus principales déficit cognitivos (atención, inhibición de respuesta y memoria de trabajo). Este trabajo revisa las recientes investigaciones que han explorado las bases neurales involucradas en las alteraciones motivacionales y emocionales mostradas por las personas con TDAH. Asimismo, se discuten las implicaciones prácticas derivadas de los resultados de estos estudios y se proponen nuevas líneas de investigación desde la Neurociencia afectiva.Attention-deficit/hyperactivity disorder (ADHD) is a complex and heterogeneous disorder that is characterized not only by cognitive deficits but also by affective dysfunctions, both motivational and emotional. Nevertheless, the neural bases of affective dysfunctions have barely been explored in relation to this disorder, in contrast to extensive research that examined the neural correlates of its main cognitive deficits (attention, response inhibition and working memory). This article reviews the available data regarding the neurobiological substrates of motivational and emotional alterations showed by children, adolescents and adults with ADHD. Practical implications derived from these data are discussed and future research directions from affective neuroscience are suggested.Estudio financiado por el Ministerio de Ciencia e Innovación (PSI2008-03688) y la Comunidad de Madrid/Universidad Autónoma de Madrid (CCG08-UAM/SAL-4463)

Efectos del contenido emocional sobre la producción del lenguaje

El contenido emocional de las palabras afecta a los procesos relacionados con su comprensión. Sin embargo, se desconoce la posible influencia que los aspectos emocionales pueden ejercer sobre la producción de las palabras. En este estudio se investigaron los correlatos electrofisiológicos mediante el uso de una tarea de identificación de letras en los nombres correspondientes a imágenes positivas, negativas y neutras. Los resultados sugieren que la información emocional captura la atención y afecta a la producción de lenguaje durante las etapas relacionadas con el acceso al concepto y a la información fonológica

Retinotopic mapping of visual event-related potentials

Visual stimulation is frequently employed in electroencephalographic (EEG) research. However, despite its widespread use, no studies have thoroughly evaluated how the morphology ofthe visual event-related potentials (ERPs) varies according to the spatial location of stimuli. Hence, the purpose of this study was to perform a detailed retinotopic mapping of visual ERPs. We recorded EEG activity while participants were visually stimulated with 60 pattern-reversing checkerboards placed at different polar angles and eccentricities. Our results show five pattern-reversal ERP components. C1 and C2 components inverted polarity between the upper and lower hemifields. P1 and N1 showed higher amplitudes and shorter latencies to stimuli located in the contralateral lower quadrant. In contrast, P2 amplitude was enhanced and its latency was reduced by stimuli presented in the periphery of the upper hemifield. The retinotopic maps presented here could serve as a guide for selecting optimal visuo-spatial locations in future ERP studiesThis work was supported by the Spanish Ministry of Science and Innovation/Economy and Competitiveness (MICINN/MINECO) (PSI2011-26314, PSI2012-34558 and PSI2014-54853-P

Magnocellular bias in exogenous attention to biologically salient stimuli as revealed by manipulating their luminosity and color

This is the author’s final version of the article, and that the article has been accepted for publication in Journal of Cognitive NeuroscienceExogenous attention is a set of mechanisms that allow us to detect and reorient toward salient events—such as appetitive or aversive—that appear out of the current focus of attention. The nature of these mechanisms, particularly the involvement of the parvocellular and magnocellular visual processing systems, was explored. Thirty-four participants performed a demanding digit categorization task while salient (spiders or S) and neutral (wheels or W) stimuli were presented as distractors under two figure–ground formats: heterochromatic/isoluminant (exclusively processed by the parvocellular system, Par trials) and isochromatic/heteroluminant (preferentially processed by the magnocellular system, Mag trials). This resulted in four conditions: SPar, SMag, WPar, and WMag. Behavioral (RTs and error rates in the task) and electrophysiological (ERPs) indices of exogenous attention were analyzed. Behavior showed greater attentional capture by SMag than by SPar distractors and enhanced modulation of SMag capture as fear of spiders reported by participants increased. ERPs reflected a sequence from magnocellular dominant (P1p, ≃120 msec) to both magnocellular and parvocellular processing (N2p and P2a, ≃200 msec). Importantly, amplitudes in one N2p subcomponent were greater to SMag than to SPar and WMag distractors, indicating greater magnocellular sensitivity to saliency. Taking together, results support a magnocellular bias in exogenous attention toward distractors of any nature during initial processing, a bias that remains in later stages when biologically salient distractors are presen

Dissociation of neural substrates of response inhibition to negative information between implicit and explicit facial go/nogo tasks: evidence from an electrophysiological study

Creative Commons Attribution LicenseBackground: Although ample evidence suggests that emotion and response inhibition are interrelated at the behavioral and neural levels, neural substrates of response inhibition to negative facial information remain unclear. Thus we used event-related potential (ERP) methods to explore the effects of explicit and implicit facial expression processing in response inhibition. Methods: We used implicit (gender categorization) and explicit emotional Go/Nogo tasks (emotion categorization) in which neutral and sad faces were presented. Electrophysiological markers at the scalp and the voxel level were analyzed during the two tasks. Results: We detected a task, emotion and trial type interaction effect in the Nogo-P3 stage. Larger Nogo-P3 amplitudes during sad conditions versus neutral conditions were detected with explicit tasks. However, the amplitude differences between the two conditions were not significant for implicit tasks. Source analyses on P3 component revealed that right inferior frontal junction (rIFJ) was involved during this stage. The current source density (CSD) of rIFJ was higher with sad conditions compared to neutral conditions for explicit tasks, rather than for implicit tasks. Conclusions: The findings indicated that response inhibition was modulated by sad facial information at the action inhibition stage when facial expressions were processed explicitly rather than implicitly. The rIFJ may be a key brain region in emotion regulation.This research was supported by the National Natural Science Foundation of China (31000503, 91232717, 31100812, 81301176, and 81300944) and the Ministry of Science and Technology (2011CB707805)

Anatomía de la mente : emoción, cognición y cerebro

Índice analítico. Resumen basado en el de la publicaciónSe explica el funcionamiento del cerebro desde el punto de vista del estudio de la mente, la Psicofisiología y la Neurofisiología. En primer lugar se describe cómo acceder a la actividad mental: cómo hacerla visible y cómo estudiarla experimentalmente. En segundo lugar, se exponen los principales resultados difundidos hasta el momento en torno a la anatomía de la emoción y la cognición (atención, memoria, lenguaje, consciencia, procesos ejecutivos, toma de decisiones y creatividad). En definitiva, se presentan los principales hallazgos en el estudio de la anatomía de la mente, es decir de la arquitectura cerebral de la emoción y la cognición humanas.MadridBiblioteca de Educación del Ministerio de Educación, Cultura y Deporte; Calle San Agustín, 5 - 3 planta; 28014 Madrid; Tel. +34917748000; [email protected]

Potenciales evocados en respuesta a expresiones faciales de emociones

Event-related potentials (ERPs) from 32 subjects in response to colour slides of four facial expressions; happy, sad, angry and neutral -presented 32 times each-, were analysed in the present experiment. The ERP structure, recorded at Fz, Cz and Pz, underwent principal component analysis (PCA). ANOVAs showed double matching, happy-angry and sad-neutral, in the N150 and P200 amplitudes. Earlier studies have associated these components with the feature analysis of stimuli. Such matchings may be explained in terms of the level to which the teeth were visible in the expressions. The results of subsequent components (N250 and P300) showed significant differences between the neutral and happy expressions. These data may be interpreted both in terms of affective and of cognitive processing. In all the cases, the amplitudes of the studied components were higher in Fz and Cz locations.En el presente experimento se analizaron los potenciales evocados (PEs) de 32 sujetos en respuesta a diapositivas en color de cuatro expresiones faciales presentadas 32 veces cada una: alegría, tristeza, ira y neutra. La estructura de los PEs registrados en Fz, Cz y Pz, se analizó vía análisis de componentes principales (ACP). Los ANOVAs indicaron que las amplitudes de N150 y P200 mostraron un doble emparejamiento alegría-ira y tristeza-neutra. Estos componentes han sido relacionados en anteriores estudios con el análisis físico de los estímulos. La visibilidad o no de los dientes en las expresiones puede explicar tales emparejamientos. Los resultados de componentes posteriores (N250 y P300) mostraron diferencias significativas entre las expresiones neutra y de alegría. Estos datos pueden ser interpretados tanto en términos de procesamiento afectivo como cognitivo. En todos los casos, Fz y Cz fueron las localizaciones donde las amplitudes de los componentes estudiados fueron mayores