Basic color terms use by aged observers: lens aging and perceptual compensation.

Basic Color Terms (BCTs) use by aged people (normal and tritanomalous) was analysed on the basis of the results provided by two visual search tasks. One task (mapping) required participants to select every stimulus that could be included in a specific BCT. Another task (best representative) required participants to select the stimulus that most accurately identified a BCT. Both tasks' results were used for two different goals. First (descriptive level), to specify the main differences between aged and young people in their use of BCTs (dimensions provided by multidimensional scaling, confusions between specific pairs of BCTs). Second (explicative level), to compare the accuracy of three models for predicting aged people's performance. Model A (filtering without compensation) assumed that aged people must use BCTs as young people do when responding to stimuli similar to the ones produced by lens aging. On the contrary, model B (filtering with compensation) assumed that lens aging effects were partially compensated by a von Kries-type mechanism (white normalisation). Finally, model C (tritan lines) assumed that ocular aging only influences S cone responses (tritan responses). Results showed that model B was the most accurate with the percentage of explained variance over 90% for both aged groups.

Basic Color Terms Use by Aged observers: lens aging and perceptual compensation

Basic Color Terms (BCTs) use by aged people (normal and tritanomalous) was analysed on the basis of the results provided by two visual search tasks. One task (mapping) required participants to select every stimulus that could be included in a specific BCT. Another task (best representative) required participants to select the stimulus that most accurately identified a BCT. Both tasks’ results were used for two different goals. First (descriptive level), to specify the main differences between aged and young people in their use of BCTs (dimensions provided by multidimensional scaling, confusions between specific pairs of BCTs). Second (explicative level), to compare the accuracy of three models for predicting aged people’s performance. Model A (filtering without compensation) assumed that aged people must use BCTs as young people do when responding to stimuli similar to the ones produced by lens aging. On the contrary, model B (filtering with compensation) assumed that lens aging effects were partially compensated by a von Kries-type mechanism (white normalisation). Finally, model C (tritan lines) assumed that ocular aging only influences S cone responses (tritan responses). Results showed that model B was the most accurate with the percentage of explained variance over 90 % for both aged groups (AU)

Los resultados proporcionados por dos tareas de búsqueda visual sirvieron para analizar el uso de los términos básicos de color (TBCs) en personas mayores (normales y tritanómalas). Una tarea (delimitación) requirió que los participantes seleccionasen todos los estímulos que podían incluirse en cada TBC concreto. La otra tarea (mejor representante) requirió que seleccionasen el estímulo que mejor identificaba a un TBC. Los resultados de ambas tareas se utilizaron con dos finalidades diferentes. La primera (nivel descriptivo) fue la de especificar las diferencias principales entre las personas mayores y jóvenes en su forma de usar los TBCs (dimensiones proporcionadas por el escalamiento multidimensional, confusiones entre pares específicos de TBCs). La segunda (nivel explicativo) fue la de comparar la adecuación de tres modelos para predecir el desempeño de las personas mayores. El modelo A (filtrado sin compensación) asumió que las personas mayores debían usar los TBCs como lo hacen las personas jóvenes al responder a estímulos similares a los que produce el envejecimiento del cristalino. Por el contrario, el modelo B (filtrado con compensación) asumió que los efectos del envejecimiento del cristalino fueron parcialmente compensados por un mecanismo tipo von Kries (normalización al blanco). Finalmente el modelo C (líneas tritán) asumió que el envejecimiento del cristalino sólo influye en las respuestas de los conos S (respuestas tritán). Los resultados mostraron que el modelo B fue el más adecuado, ya que llegó a explicar más del 90% de la varianza en ambos grupos de personas mayores (AU)