LAUSR

Reaction times to targets presented at previously stimulated locations are longer after some time (approx. 300 ms) than to targets presented in new locations. This effect is widely known as Inhibition of Return (IOR). It is typically explained in terms of an inhibitory bias against returning attention to places previously attended to and thus promoting attentional activity elsewhere. Regardless of its attentional character, IOR seems to encapsulate the interaction between two fundamental dimensions of temperament: engaging in versus inhibition and withdrawal from activity. Approaching IOR in this perspective, the question has arisen as to whether individual differences in reactivity as a temperamental trait express themselves in the time course and magnitude of this effect. 90 subjects (30 low, 30 medium and 30 highly reactive individuals) participated in the study. To the best of our knowledge, there are no other studies of individual differences in these parameters of IOR that use saccadic responses to measure its effect on behavior. The results show that in individuals who are higher in terms of their reactivity, IOR starts earlier and continues at the following SOAs but its magnitude is smaller than in less reactive individuals. The results are explained and discussed in light of the Regulative Theory of Temperament. This is the final version of the Abstract which has been accepted in the revised manuscript.