Control inhibitorio en la orientación atencional : una revisión sobre la inhibición de retorno

Abstract

espanolCuando exploramos el ambiente en busca de informacion relevante para la conducta, si la atencion se dirige al lugar donde se encuentra tal informacion relevante la ejecucion mejora considerablemente. En situaciones altamente demandantes puede ser crucial por tanto el dirigir la atencion al lugar adecuado. Asi, cuando en la busqueda de un objetivo se deben explorar diferentes lugares de forma consecutiva, la implementacion de un mecanismo que inhiba la vuelta a lugares previamente explorados seria altamente adaptativo, especialmente cuando se debe minimizar el tiempo de busqueda. Los estudios sobre orientacion atencional Llevados a cabo con el paradigma de costos y beneficios han mostrado la existencia de ambos efectos: la facilitacion inicial en d procesamiento de informacion que aparece en el lugar (u objeto) donde se ha dirigido la atencion, y el subsiguiente deficit en el procesamiento en ese mismo lugar u objeto cuando, una vez retirada la atencion, debe volver al mismo sitio. En este trabajo revisamos la literatura experimental sobre este segundo efecto inhibitorio, denominado Inhibicion de Retorno: caracteristicas del efecto, bases neuroanatomicas y coordenadas de representacion. En los ultimos anos se habia cuestionado la naturaleza atencional del efecto de Inhibicion de Retorno, y con ello su importancia como revelador de la existencia de un mecanismo inhibitorio de orientacion atencional, dado que solo se obtenia con tareas que implicaban exclusivamente la deteccion o localizacion de un objetivo, pero no cuando la respuesta implica la discriminacion del mismo. Sin embargo, recientes publicaciones muestran que cuando se utilizan los procedimientos y parametros adecuados el efecto aparece tanto con tareas de deteccion como de discriminacion EnglishWhen the environment is searched for a target relevant to behavior, performance is considerably improved if attention is oriented toward the target location. In demanding situations orienting attention to the right location can be crucial. Thus, when several locations have to be explored consecutively, the action of a mechanism which inhibits attention from returning to previously explored locations would be highly adaptive, particularly under time pressure. Orienting of attention research with the cost-benefit paradigm has shown both effects, i.e. the initial benefit of processing in the location (or object) to which attention is oriented, and a subsequent cost at the same location (or object) once attention has been withdrawn. Here we provide a review of the experimental literature about the inhibitory effect, which is called Inhibition of Return: We focus on characteristics and boundary conditions of the effect, its neural basis, and the frames of reference in wich it can operate. Recently, it has been argued that this effect can only be obtained when stimulus detection or localization is the required response, but not when discrimination is necessary. Because of that, some have argued that Inhibition of Return is not an attentional effect; and some have questioned its importance as an inhibitory mechanism in orienting of attention. However, recent publications have shown that the effect is equally consistent in detection and discrimination tasks, when appropriate procedures and parameters are used. However, its time course depends on the task. In the last part of this work the theoretical implications of this dissociation are analyzed. We conclude that the dependence of the effect on the task could reveal the flexibility of the attentional system to adapt to processing demands, in such a way that resources are maximized to obtain information in the interaction with the environment.