Response processing during visual search in normal aging: the need for more time to prevent cross talk between spatial attention and manual response selection

[Abstract] It is still not well known whether the age-related behavioural slowing observed during visual search is due to changes in the allocation of attention, in response activation patterns, or to a combination of both. To help in clarifying it, attention-related (N2 posterior contralateral; N2pc, and N2 central contralateral; N2cc) and response-related (Motor Potential; MP, and Reafferent Potential; RAP) event-related potentials (ERPs) were obtained in healthy young and older participants executing a visual search task. Age was associated with N2pc and N2cc longer latencies, earlier MP onsets and longer MP rise times. Lower N2pc, higher MP and lower RAP amplitudes were also observed. Results suggest that older participants need more time to allocate spatial attention onto the target (N2pc) and to prevent cross talk between response selection and attention direction (N2cc), and that they are slower and need higher cortical activation when preparing and executing correctly selected responses (MP).Ministerio de Ciencia e Innovación; PSI2010-21427Xunta de Galicia; 10PXIB211220P

Response processing during visual search in normal aging: the need for more time to prevent cross talk between spatial attention and manual response selection

It is still not well known whether the age-related behavioural slowing observed during visual search is due to changes in the allocation of attention, in response activation patterns, or to a combination of both. To help in clarifying it, attention-related (N2 posterior contralateral; N2pc, and N2 central contralateral; N2cc) and response-related (Motor Potential; MP, and Reafferent Potential; RAP) event-related potentials (ERPs) were obtained in healthy young and older participants executing a visual search task. Age was associated with N2pc and N2cc longer latencies, earlier MP onsets and longer MP rise times. Lower N2pc, higher MP and lower RAP amplitudes were also observed. Results suggest that older participants need more time to allocate spatial attention onto the target (N2pc) and to prevent cross talk between response selection and attention direction (N2cc), and that they are slower and need higher cortical activation when preparing and executing correctly selected responses (MP).This study was supported by grants from the Spanish MICINN (PSI2010-21427) and Xunta de Galicia (10PXIB211220PR)S

Le P3 en tant qu’index du niveau de performance de sujets âgés impliqués dans une tâche visuelle

Aim: To explore the possible changes in the parameters of the P3 event-related potential (ERP) component among groups of young and older healthy subjects characterized as either high- or low-performers in a visual attention task. Methods: Both conventional and single-trial analyses of the visual P3 component were performed on each group of subjects. Results: P3 component significantly increased in latency as a function of age. The high-performing older subjects showed the posterior predominance of P3, as in young subjects. However, the low-performing older subjects showed a significant P3 amplitude reduction at posterior locations and topographically more widespread activity. Furthermore, single-trial analysis showed that low-performing older subjects presented higher intertrial variability in P3 latency, few trials with P3 generation, and a reduced P3 amplitude in these trials in whom P3 was generated. Conclusion: These data suggest a specific decline in visual target processing in the low-performing older subjects, which would imply a reduction in these attentional brain resources that are allocated to correctly select the relevant stimuli. The implications of this finding for the actual compensation versus dedifferentiation debate in normal aging are discussedBut: Comparer les paramètres du composant P3 des potentiels évoqués dans un groupe de sujets jeunes en bonne santé et dans un groupe de sujets âgés classifiés en fonction de leur niveau d’exécution d’une tâche d’attention visuelle (meilleurs et moins bons exécuteurs). Méthodes: Des analyses conventionnelles et des analyses « en sweep unique » du composant P3 ont été réalisées dans chaque groupe de sujets. Résultats: Le temps de latence du composant P3 augmente de façon significative avec l’âge. Chez les sujets âgés meilleurs exécuteurs le P3 prédominait au niveau des régions postérieures, comme chez les sujets jeunes. Par contre, chez les sujets âgés moins bons exécuteurs, le P3 était significativement moins ample en postérieur et plus diffusément réparti sur le scalp. Les analyses « en sweep unique » ont montré que ces derniers présentaient une plus grande variabilité interessai en ce qui concerne le temps de latence de P3, moins de tests où le P3 était présent, ainsi qu’une réduction de l’amplitude de P3 dans les tests où il était présent. Conclusion: Ces données suggèrent l’existence d’un déficit du traitement visuel des stimuli chez les sujets âgés moins bons exécuteurs qui pourrait consister en une réduction des ressources cérébrales attentionnelles mobilisées pour sélectionner correctement le stimulus approprié. Nous discutons les implications de ces résultats dans le débat concernant la redistribution des aires corticales actives chez les sujets âgés (hypothèses de compensation versus dédifférentiation)This research was supported by grants from the Spanish MEC (SEJ2004-01377) and Xunta de Galicia (PGIDT05PXIC21101PN)S

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

Vertical asymmetries and inhibition of return: effects of spatial and non-spatial cueing on behavior and visual ERPs

[Abstract] The mechanisms underlying inhibition of return (IOR) are still under debate. Besides the probable implication of several processes in its generation, a reason for this uncertainty may be related to experimental factors affecting the presence, time course, and magnitude of IOR. Two of them may be related to the arrangement of the stimuli in the visual field that could cause possible interactions between IOR and response conflict effects (horizontal arrangements) or between IOR and perceptual asymmetries (vertical arrangement). The purpose of the present study was to explore location and color cueing effects with a vertical arrangement of stimuli, free of S–R compatibility effects. To examine this possibility, a cue-back task with stimuli in the vertical meridian was employed. Targets could randomly and equiprobably appear at cued or uncued locations, or with cued or uncued color. These cueing effects were analyzed on behavior and ERPs separately for upper and lower visual fields (UVF and LVF). Under location cueing, behavioral responses were slower (spatial IOR) in both hemifields. In the ERPs, N1 reductions were observed in both visual fields although with different modulations in their latency and scalp distribution. In the P3 rising beginning, posterior negative deflections in the LVF (Nd) and anterior positive deflections (Pd) in the UVF were observed. Under color cueing, P3 amplitude was reduced in the UVF accompanied by no behavioral effects. These results suggest that different patterns of brain activation can be obtained in upper and lower visual fields under spatial- and non-spatial cueing conditions.Ministerio de Economía, Industria y Competitividad; PSI2010-21427Xunta de Galicia; 10PXIB211220P

Research ethics review system state in Argentina and the adaptation in response to the COVID-19 pandemic

Fil: Palmero, Ana. Ministerio de Salud de la Nación; Argentina.Fil: Torales, Santiago. Ministerio de Salud de la Nación; Argentina.Fil: Garau, Laura. Ministerio de Salud de la Ciudad Autónoma de Buenos Aires; Argentina.Fil: Álvarez, Jorgelina. Ministerio de Salud, Desarrollo Social y Deportes de Mendoza; Argentina.Fil: Martinelli, Beatriz. Ministerio de Salud de Santa Fe; Argentina.Fil: Vukotich, Claudia. Ministerio de Salud de la Ciudad Autónoma de Buenos Aires; Argentina.Fil: Sanchez, Silvina. Ministerio de Salud de la Provincia de Buenos Aires; Argentina.Fil: Burger, Carlos. Ministerio de Salud de la Provincia de Buenos Aires; Argentina.Fil: Mercado, Daniel. Ministerio de Salud de Córdoba; Argentina.Fil: Lencina, Verónica. Ministerio de Salud de Salta; Argentina.Fil: Oliva, Valeria. Ministerio de Salud de Salta; Argentina.Fil: Anze, Ismael. Ministerio de Salud de Salta; Argentina.Fil: Apaza, Gladis. Ministerio de Salud de Jujuy; Argentina.Fil: Bazán de Casella, María Cristina. Ministerio de Salud de Tucumán; Argentina.Fil: Burgos, Graciela. Ministerio de Salud de Santiago del Estero; Argentina.Fil: Martín, María Cristina. Ministerio de Salud de Misiones; Argentina.Fil: Margaria, Laura. Ministerio de Salud de Río Negro; Argentina.Fil: Manonelles, Gabriela. Ministerio de Salud de Santa Cruz; Argentina.Fil: Benzi, Patricia. Ministerio de Salud de Entre Ríos; Argentina.Fil: Pérez Pazo, Andrea. Ministerio de Salud Pública de San Juan; Argentina.INTRODUCCIÓN: un sistema de evaluación ética de las investigaciones en seres humanos es esencial para proteger los derechos de los participantes. Los desafíos impuestos por la pandemia de la COVID-19 para conducir investigaciones éticas que produzcan resultados con rapidez demuestran la necesidad de fortalecerlo. El objetivo de este estudio fue describir el estado de situación de los sistemas de evaluación ética de las provincias de Argentina y las adaptaciones realizadas por la pandemia. MÉTODOS: se realizó una encuesta a los comités provinciales de ética en investigación o áreas similares de los ministerios de Salud que ejercen la vigilancia sobre la evaluación ética de las investigaciones de su jurisdicción. RESULTADOS: respondieron 16 de las 17 provincias encuestadas. El 93,7% de los comités provinciales evalúa investigaciones en seres humanos y tiene procedimientos operativos estandarizados (POE). El 68,7% lleva un registro de los comités de ética en investigación (CEI) de su jurisdicción. Un 75% acredita a los CEI y un 68,7% los supervisa. El 100% tiene un registro de las investigaciones en salud; en 56,2% de los casos este registro es público. Del total, 81,2% realizan actividades de capacitación. El 100% adaptó los POE para evaluar estudios sobre la COVID-19. DISCUSIÓN: los resultados muestran sistemas provinciales consolidados. Se requiere fortalecer la transparencia en la investigación mediante el registro público de las investigaciones. Se identificaron posibilidades de mejora para proponer acciones a futuro

Research ethics review system state in Argentina and the adaptation in response to the COVID-19 pandemic

Fil: Palmero, Ana. Ministerio de Salud de la Nación; Argentina.Fil: Torales, Santiago. Ministerio de Salud de la Nación; Argentina.Fil: Garau, Laura. Ministerio de Salud de la Ciudad Autónoma de Buenos Aires; Argentina.Fil: Álvarez, Jorgelina. Ministerio de Salud, Desarrollo Social y Deportes de Mendoza; Argentina.Fil: Martinelli, Beatriz. Ministerio de Salud de Santa Fe; Argentina.Fil: Vukotich, Claudia. Ministerio de Salud de la Ciudad Autónoma de Buenos Aires; Argentina.Fil: Sanchez, Silvina. Ministerio de Salud de la Provincia de Buenos Aires; Argentina.Fil: Burger, Carlos. Ministerio de Salud de la Provincia de Buenos Aires; Argentina.Fil: Mercado, Daniel. Ministerio de Salud de Córdoba; Argentina.Fil: Lencina, Verónica. Ministerio de Salud de Salta; Argentina.Fil: Oliva, Valeria. Ministerio de Salud de Salta; Argentina.Fil: Anze, Ismael. Ministerio de Salud de Salta; Argentina.Fil: Apaza, Gladis. Ministerio de Salud de Jujuy; Argentina.Fil: Bazán de Casella, María Cristina. Ministerio de Salud de Tucumán; Argentina.Fil: Burgos, Graciela. Ministerio de Salud de Santiago del Estero; Argentina.Fil: Martín, María Cristina. Ministerio de Salud de Misiones; Argentina.Fil: Margaria, Laura. Ministerio de Salud de Río Negro; Argentina.Fil: Manonelles, Gabriela. Ministerio de Salud de Santa Cruz; Argentina.Fil: Benzi, Patricia. Ministerio de Salud de Entre Ríos; Argentina.Fil: Pérez Pazo, Andrea. Ministerio de Salud Pública de San Juan; Argentina.INTRODUCCIÓN: un sistema de evaluación ética de las investigaciones en seres humanos es esencial para proteger los derechos de los participantes. Los desafíos impuestos por la pandemia de la COVID-19 para conducir investigaciones éticas que produzcan resultados con rapidez demuestran la necesidad de fortalecerlo. El objetivo de este estudio fue describir el estado de situación de los sistemas de evaluación ética de las provincias de Argentina y las adaptaciones realizadas por la pandemia. MÉTODOS: se realizó una encuesta a los comités provinciales de ética en investigación o áreas similares de los ministerios de Salud que ejercen la vigilancia sobre la evaluación ética de las investigaciones de su jurisdicción. RESULTADOS: respondieron 16 de las 17 provincias encuestadas. El 93,7% de los comités provinciales evalúa investigaciones en seres humanos y tiene procedimientos operativos estandarizados (POE). El 68,7% lleva un registro de los comités de ética en investigación (CEI) de su jurisdicción. Un 75% acredita a los CEI y un 68,7% los supervisa. El 100% tiene un registro de las investigaciones en salud; en 56,2% de los casos este registro es público. Del total, 81,2% realizan actividades de capacitación. El 100% adaptó los POE para evaluar estudios sobre la COVID-19. DISCUSIÓN: los resultados muestran sistemas provinciales consolidados. Se requiere fortalecer la transparencia en la investigación mediante el registro público de las investigaciones. Se identificaron posibilidades de mejora para proponer acciones a futuro

Vertical asymmetries and inhibition of return: Effects of spatial and non-spatial cueing on behavior and visual ERPs

Themechanisms underlying inhibition of return (IOR) are still under debate. Besides the probable implication of several processes in its generation, a reason for this uncertainty may be related to experimental factors affecting the presence, time course, and magnitude of IOR. Two of them may be related to the arrangement of the stimuli in the visual field that could cause possible interactions between IOR and response conflict effects (horizontal arrangements) or between IOR and perceptual asymmetries (vertical arrangement). The purpose of the present studywas to explore location and color cueing effects with a vertical arrangement of stimuli, free of S–R compatibility effects. To examine this possibility, a cue-back task with stimuli in the vertical meridian was employed. Targets could randomly and equiprobably appear at cued or uncued locations, or with cued or uncued color. These cueing effects were analyzed on behavior and ERPs separately for upper and lower visual fields (UVF and LVF). Under location cueing, behavioral responses were slower (spatial IOR) in both hemifields. In the ERPs, N1 reductions were observed in both visual fields although with different modulations in their latency and scalp distribution. In the P3 rising beginning, posterior negative deflections in the LVF (Nd) and anterior positive deflections (Pd) in the UVF were observed. Under color cueing, P3 amplitude was reduced in the UVF accompanied by no behavioral effects. These results suggest that different patterns of brain activation can be obtained in upper and lower visual fields under spatial- and non-spatial cueing conditions.This study was supported by grants from the Spanish MICINN (PSI2010-21427) and Xunta de Galicia (10PXIB211220PR). S.D. was supported by an Isidro Parga Pondal contract (Xunta de Galicia, Spain)S