Do dichromats see colours in this way? Assesing simulation tools without colorimetric measurements / ¿Son estos los colores que ven los dicrómatas? Evaluando herramientas de simulación sin mediciones colorimétricas

BACKGROUND: Simulcheck evaluates Colour Simulation Tools (CSTs, they transform colours to mimic those seen by colour vision deficients). Two CSTs (Variantor and Coblis) were used to know if the standard Simulcheck version (direct measurement based, DMB) can be substituted by another (RGB values based) not requiring sophisticated measurement instruments. METHOD: Ten normal trichromats performed the two psychophysical tasks included in the Simulcheck method. The Pseudoachromatic Stimuli Identification task provided the huv (hue angle) values of the pseudoachromatic stimuli: colours seen as red or green by normal trichromats but as grey by colour deficient people. The Minimum Achromatic Contrast task was used to compute the LR (relative luminance) values of the pseudoachromatic stimuli. RESULTS AND CONCLUSIONS: Simulcheck DMB version showed that Variantor was accurate to simulate protanopia but neither Variantor nor Coblis were accurate to simulate deuteranopia. Simulcheck RGB version provided accurate huv values, so this variable can be adequately estimated when lacking a colorimeter -an expensive and unusual apparatus-. Contrary, the inaccuracy of the LR estimations provided by Simulcheck RGB version makes it advisable to compute this variable from the measurements performed with a photometer, a cheap and easy to find apparatus

ANTECEDENTES: Simulcheck evalúa Herramientas de Simulación del Color (HSCs, transforman los colores para imitar lo que ven las personas con deficiencias en la visión cromática). Se utilizaron dos HSCs (Variantor y Coblis) para evaluar si la versión estándar de Simulcheck (basada en mediciones directas, BMD) puede sustituirse por otra que no requiere instrumentos de medición sofisticados (basada en valores RGB). MÉTODO: diez tricrómatas realizaron las tareas psicofísicas incluidas en el método Simulcheck. La de Identificación de Estímulos Pseudoacromáticos proporcionó el ángulo cromático (huv) de los estímulos que los observadores comunes ven rojos o verdes, pero grises las personas con deficiencias en la visión cromática. La de Mínimo Contraste Acromático proporcionó los valores LR (luminancia relativa) de los estímulos pseudoacromáticos. RESULTADOS Y CONCLUSIONES: la versión BMD mostró que Variantor simuló adecuadamente la protanopia, pero que ni Variantor ni Coblis fueron adecuados para la deuteranopia. La Versión RGB del método Simulcheck proporcionó valores huv adecuados, consecuentemente se concluyó que esta variable puede estimarse adecuadamente sin un colorímetro -aparato caro e inusual-. Por el contrario, la inadecuación de las estimaciones de LR proporcionadas por la versión RGB recomienda computar esta variable usando mediciones realizadas con un fotómetro, un aparato barato y fácil de encontrar

The inter-relations between spatial and object factors during sustained visual attention to dynamic objects

El objetivo principal de esta investigación era el estudio de la atención a estímulos visuales dinámicos. Los observadores tenían que atender a un número variable de objetos en movimiento durante un periodo sostenido de varios minutos. Un estímulo objetivo de corta duración aparecía, a intervalos al azar, dentro de alguno de esos objetos. La tarea del observador era identificar este estímulo. Las variables manipuladas fueron el número de objetos relevantes y la fuerza del agrupamiento perceptual entre ellos, medida por el tamaño del espacio limitado por esos objetos. Los resultados indican que nuestra atención solo puede rastrear un objeto de cada vez, a menos que los objetos atendidos formen un grupo perceptivo. En ese caso, podríamos atender a más de un objeto simultáneamente, pero los efectos dependerían de la percepción de las relaciones espaciales entre ellos (AU)

The main goal of our research was to investigate attention to dynamic visual stimuli. Observers were instructed to attentively track a variable number of moving visual objects for a sustained period of several minutes. At random intervals, a target stimulus of brief duration was presented inside one of these objects and observers were required to identify it. The number of relevant objects to be tracked and the grouping strength among objects that had to be attended, operationalized as the size of relative area among those objects, were manipulated. The results indicated that only a single object could be attentively tracked, unless the objects formed a perceptual group. In this case, more than one dynamic object could be attended, but effectiveness of attention would be mediated by perception of the spatial relations among them (AU)

Locating basic Spanish colour categories in CIE L*u*v* space: Identification, lightness segregation and correspondence with English equivalents

Se realizaron cinco experimentos para identificar las categorías cromáticas básicas (CCB) del español y ubicarlas en el espacio CIE L*u*v*. Empleando una tarea de listas elicitadas y otra de denominación monolexémica libre, se confirmó la existencia de 11 CCB. Mediante una tarea de estimación de sinonimia, se concluyó que, en español, se emplean 2 términos sinónimos (morado y violeta) para denominar una categoría equivalente a la inglesa purple. Tres experimentos proporcionaron información acerca de la localización colorimétrica de las 11 CCB del español. Dos emplearon tareas de denominación monolexémica (libre y restringida) y el tercero requirió la señalización de prototipos y de buenos ejemplares. Se observó que las CCB del español y del inglés son esencialmente equivalentes en número y delimitación colorimétrica, por lo puede considerarse que nuestro trabajo extiende y complementa la investigación previa (sobre CCB inglesas) en lo referente a la localización de las categorías acromáticas en el espacio de color, los vínculos entre categorías cromáticas y acromáticas (ni rojo ni naranja tienen vínculos directos con las categorías acromáticas), y la dependencia de la claridad que muestra el uso de las CCB. Por último, destaca la existencia de 2 categorías próximas a ser básicas: beige y granate(AU)

Five experiments were performed to identify the basic Spanish colour categories (BCCs) and to locate them in the CIE L*u*v* space. The existence of 11 BCCs was confirmed using an elicited list task and a free monolexemic naming task. From the results provided by a synonymicity estimation task, it was concluded that, in Spanish, 2 synonymous terms (morado and violeta) are used to name a category equivalent to the English category purple. Three experiments provided information about the colourimetric localization of the 11 Spanish BCCs. Two experiments used monolexemic naming tasks (free and restricted) and a third required the free signalling of prototypes and good exemplars. It was observed that Spanish and British BCCs are essentially equivalents in number and colourimetric delimitation and, therefore, our work can be considered to extend and complement previous research (on English BCCs) insofar as achromatic categories in colour space localization, the links between chromatic and achromatic categories (red and orange have no direct links with achromatic categories), and the dependence of the use of BCCs on lightness are concerned. Lastly, our results indicate the existence of 2 categories that are nearly basic: beige and garnet(AU)

Inteligencia emotional e interferencia Sroop Emocional en Participantes con Ansiedad Rasgo Elevada VS. Baja / Emotional Intelligence and emotional stroop interference in participants whit hihg vs. low trait anxiety

Participantes seleccionados por sus elevadas o bajas puntuaciones de ansiedad-rasgo en el STAI realizaron una area stroop emocinal de nobrar color y cumplimentaron el TMMS. Los resultados color y cumplimentaron el TMMS. Los resultados indicaron que las personas con ansiedad elevada tardaban más en nombrar el color de las palabras amenazantes de alencia negativa que las de valencia positiva. Además los participantes con puntuaciones inferiores a la mediana en el factor Claridad del TMMS ardaban más en nombrar el color de las palabras negativas en comparación con las positivas . Finalmente encontramos que los participantes del grupo de ansiedad elevada mostraban la inererencia stroop emocional independientemente de su nivel de Atención en el TMMS. Sin embargo, en el grupo de ansiedad baja sólo se observó la inerferencia stroop emocional si su nivel de Atención era bajo. Discutmos la relevancia de estos datos par ala compresión de la IE, evaluada con el TMMS y de sus relaciones con la ansiedad(AU)

Emotional Intelligence and emotional stroop interference in participants whit hihg vs. low trait anxietyParticipants in this reseach were selected on the bais of thir high vs. low socre on STAI and performed an emotional stroop colour-narming task and filled in the TMMS. Reuslts showed that participants who scored high on anxiety took longer in naming the colour of negative threatening words than that of positive words. Futhermore, participats scoring below the median on the Carity factor of the TMMS showed the emotional stroop intererence. Finally, we observed that participants in the hihg anxiety group showed emotional stroop, interference independently of their TMMS, Attention level. However, participants with low anxiety score only showed the emotional stroop intererence provided a low level of Attenion. In contrast, the opposite effect, i.e. longerreponses for positive words, was shown by low anxiety participants who scored high on Attention. The overall patter of results is discussed in the context of their relevance for understanding Emotional Intelligence, as measured by the TMMS, and its relation to anxiety(AU)

Delayed P300 during Sternberg and color discrimination tasks in poor readers.

The P300 ERP component was studied in poor and normal readers, using Sternberg and color discrimination (Spaceships) tasks. During the first one, subjects must decide if a probe item belongs or not to a set of digits previously presented. In the second one, the participants must shoot violet spaceships with one key and other than violet spaceships with another key. There were no significant differences between groups with respect to reaction times, but a larger proportion of errors was observed in poor readers. Longer P300 latencies were recorded for poor readers than controls in both tasks. P300 amplitudes showed topographical differences between the two groups: Poor readers' P300 is larger frontally during the Sternberg task, but smaller at posterior sites during the Spaceships task. These results suggest that poor readers may have deficiencies during the early processing stage, such as visual stimulus evaluation. Poor readers also appear to have deficits for classifying and memorizing visual stimuli.

Extent and duration of practice effects on performance with the Farnsworth-Munsell 100-Hue test.

The extent and persistence of practice effects on serial performance in the Farnsworth-Munsell 100-Hue test (100-Hue test) were evaluated in an experiment in which six subjects performed the 100-Hue test up to 17 times over six weeks, and then once more after 7 months. A practice effect occurred which was highly statistically significant for the group as a whole (P < 0.001) and for three individual subjects (P < 0.05). A practice effect was still evident 7 months after the last test performance. Error scores were reduced almost to zero after 5-10 retests so that it was unclear whether the effects of practice had disappeared or whether failure to improve further was a 'floor effect'. As a control against a floor effect, a second experiment was performed in which subjects' performance was impaired by placing neutral density filters in front of their eyes (thus artificially raising their 100-Hue error score). Under these conditions, error scores continued to fall and were halved after 17 tests (P < 0.03). It is concluded that practice has a large effect on 100-Hue test performance which continues over many retests and for many months after testing.