Cost of mental set reconfiguration between digits and their photisms in synaesthesia.

In this study we present an experiment investigating the reconfiguration process elicited by the task switching paradigm in synaesthesia. We study the time course of the operations involved in the activation of photisms. In the experimental Group, four digit-color synaesthetes alternated between an odd-even task and a color task (to indicate the photism elicited by each digit). In both tasks, the target stimuli were numbers between 1 and 9 written in white. One of the control groups ran the same tasks but this time with colored numbers (Naive Control Group). The results of these studies showed the expected pattern for the control group in the case of regular shift: a significant task switch cost with an abrupt offset and a cost reduction in long RSI. However for the experimental group, we found switch cost asymmetry in the short RSI and non-significant cost in the long RSI. A second control group performed exactly the same tasks as the experimental group (with white numbers as targets and a second imaginary color task) -Trained Control Group-. We found no cost for this second control group. This means that the cost of mental set reconfiguration between numbers (inducers) and their photisms (concurrent sensations) occurs, that there is a specific cost asymmetry (from photisms to inducers) and that this cost cannot be explained by associative learning. The results are discussed in terms of exogenous and endogenous components of mental set reconfiguration.

Cost of mental set reconfiguration between digits and their photisms in synaesthesia

In this study we present an experiment investigating the reconfiguration process elicited by the task switching paradigm in synaesthesia. We study the time course of the operations involved in the activation of photisms. In the experimental Group, four digit-color synaesthetes alternated between an odd-even task and a color task (to indicate the photism elicited by each digit). In both tasks, the target stimuli were numbers between 1 and 9 written in white. One of the control groups ran the same tasks but this time with colored numbers (Naïve Control Group). The results of these studies showed the expected pattern for the control group in the case of regular shift: a significant task switch cost with an abrupt offset and a cost reduction in long RSI. However for the experimental group, we found switch cost asymmetry in the short RSI and non-significant cost in the long RSI. A second control group performed exactly the same tasks as the experimental group (with white numbers as targets and a second imaginary color task) -Trained Control Group-. We found no cost for this second control group. This means that the cost of mental set reconfiguration between numbers (inducers) and their photisms (concurrent sensations) occurs, that there is a specific cost asymmetry (from photisms to inducers) and that this cost cannot be explained by associative learning. The results are discussed in terms of exogenous and endogenous components of mental set reconfiguration (AU)

En este estudio presentamos un experimento en el que se investiga el proceso de reconfiguración mental empleando el paradigma de cambio de tarea en sinestesia. Estudiamos el tiempo de preparación necesario en la activación de un fotismo. En el grupo experimental, cuatro sinestetas dígito-color alternaban entre una tarea de números (par-impar) y otra de color (indicar el fotismo evocado por cada dígito). En ambas tareas, el estímulo era un número entre el 1 y el 9 escrito en blanco. Uno de los grupos control realizó la misma tarea pero con los números coloreados (Naïve Control Group). Los resultados muestran el patrón de datos esperado para el grupo control en el caso de cambio de tarea predecible: un coste por cambio de tarea que desaparece en el primer ensayo de repetición usando un intervalo respuesta estímulo (RSI) largo. Sin embargo, en el grupo experimental, encontramos asimetrías en el patrón del costo usando RSI corto y un coste no significativo en el RSI largo. Un segundo grupo control realizó exactamente la misma tarea que el grupo experimental (con números en blanco y una segunda tarea de «color imaginario») -Trained Control Group-. Encontramos que no existe costo en este segundo grupo de control. Esto significa que el coste por la reconfiguración mental al alternar entre tarea de números (inductores) y su fotismo (sensación concurrente) ocurre, que hay una asimetría del costo específica (del fotismo a los inductores) y que este costo no puede ser explicado mediante el aprendizaje asociativo. Estos resultados se discuten en términos de los componentes exógenos y endógenos de la reconfiguración mental (AU)

Sequential effects in deduction: vost of inference switch

El paradigma de cambio de tarea ha ayudado a los psicólogos a conocer los procesos involucrados en el cambio de una actividad a otra. La literatura aporta resultados consistentes sobre la reconfiguración necesaria para el cambio de tarea (desaparición abrupta del coste cuando el cambio es predecible vs. reducción gradual del coste en condiciones de cambio impredecible; componentes endógeno y exógeno del coste; asimetría del coste…). En la investigación que presentamos aquí mostramos los resultados de varios experimentos en los que estudiamos el proceso de reconfiguración que se produce al alternar entre Modus Ponens y Modus Tollens. Los resultados muestran que el cambio de una inferencia a otra produce un empeoramiento en el número de errores de los participantes, así como un aumento en los tiempos de reacción (coste por interferencia del cambio). Además, encontramos una mejora gradual en el Modus Tollens en secuencias no predecibles y con intervalos respuesta-estímulo largos, en los ensayos de repetición de tarea. Ambos resultados son compatibles con la hipótesis de la reconfiguración de tarea(AU)

The task-switch paradigm has helped psychologists gain insight into the processes involved in changing from one activity to another. The literature has yielded consistent results about switch cost reconfiguration (abrupt offset in regular task-switch vs. gradual reduction in random task-switch; endogenous and exogenous components of switch cost; cost asymmetry...). In this study we present several experiments in which we investigated the reconfiguration process elicited by task switching between Modus Ponens and Modus Tollens. We found that the switch from one inference to a new one produces impairment in accuracy as an increase in reaction time (cost of inference switch). Moreover, with random sequences and a long response stimulus interval we found a gradual improvement in Modus Tollens repetitions. Both results are compatible with the task reconfiguration hypothesis(AU)

Synaesthesia: the existing state of affairs.

In synaesthesia one type of stimulation evokes the sensation of another, such as when hearing a sound produces photisms--that is, mental percepts of colours. In the past, the idiosyncrasy of this phenomenon, as well as the natural mistrust of scientists towards the subjective, consigned synaesthesia to the periphery of scientific interest. However, the landscape has changed radically in the last two decades. The labour of many researchers, inside as well as outside of cognitive neuroscience, has transformed synaesthesia into a scientific reality whose existence can be demonstrated and studied empirically. The present paper summarizes and reflects on our current knowledge concerning synaesthesia in all its aspects (cognition, behaviour, neurology, genetics, and demographics).

The nature of residual cost in regular switch response factors.

Two experiments are presented that compare the residual cost found when switching from one task to another under predictable conditions. The aim of the study was to explore the roles played by the stimulus, the response, or both in the process of the mental set reconfiguration necessary to switch between two tasks. The experiments tested [Rogers, R. D., & Monsell, S. (1995). Cost of a predictable switch between simple cognitive tasks. Journal of Experimental Psychology: General, 124, 207-231] stimulus-cued-completion hypothesis and [Schuch, S., & Koch, I. (2003). The role of response selection for inhibition of task sets in task shifting. Journal of Experimental Psychology: Human Perception and Performance, 29, 92-105] hypothesis of response selection as the key factor in the nature of switch cost. In the first experiment, two conditions were created that varied in terms of a Go/No-Go signal: The Go trials were a replication of [Tornay, F. J., & Milán, E. G. (2001). A more complete task-set reconfiguration in random than in predictable task switch. The Quarterly Journal of Experimental Psychology, 54A, 785-803 Experiment 3]; The No-Go trials were identical to the first condition, except that participants did not execute a response in the trial n-1 (Schuch & Koch, 2003). In addition, the percentage of Go and No-Go trials was manipulated. The results showed that the cost was significant only in the high Go signal-frequency case (Experiment 2), with an abrupt offset in Go trials and a gradual offset in No-Go trials. Based on the results of these experiments, it was concluded that the crucial factor to complete a mental set reconfiguration is response-related and not stimulus-related.

Exploring task-set reconfiguration with random task sequences.

Switching between two different tasks normally results in an impairment in people's performance known as a switch cost, typically measured as an increase in reaction time (RT) and errors compared to a situation in which no task switch is required. Researchers in task switching have suggested that this switch cost is the behavioural manifestation of the task set reconfiguration processes that are necessary to perform the upcoming task. However, an examination of the literature in task switching reveals apparently contradictory results about the nature of task set reconfiguration processes. In Experiment 1, we addressed this issue by comparing participants' performance in two different experimental conditions: predictable task switching and random task switching. In the predictable switch condition the switch cost completely vanished after the first repetition of the new task. However, in the random switch condition, while the difference between switch and repetition trials was not significant, we observed a significant reduction in RT between the first and second repetition of the new task. In Experiment 2, we further investigated the pattern of task set reconfiguration in the random switch situation. The results showed a progressive reduction of participants' response latencies across repetitions of the same task. The present study demonstrates that, whereas the results in predictable switching conditions are compatible with an exogenous-reconfiguration hypothesis, random task switching produces a more gradual, decay-like switch cost reduction with task repetition.