Hypnotizability and temporal dynamics of attention: a study on the Attentional Blink effect

This study was designed to seek hypnotizability-related differences in attention temporal dynamics. For this purpose, an iconic version of the Attentional Blink Task (AB) was performed on 18 highly (Highs, score 9–12, SHSS form C) and 18 low susceptible individuals (Lows, score 0–3). The procedure consisted of two tasks in which two animal shapes (a coloured animal, Target, and a black butterfly, Probe) appeared in close temporal proximity within a rapid stream of distractors (black animals). In the Single task only Probe detection was required; in the Conditional task, Target identification was also requested. In this case, competition between Target and Probe for limited attentional resources decreases Probe visibility as a function of the time lag from Target (AB effect). A similar AB effect occurred in the two groups; nonetheless, Probe detection scores at the shorter lags were frequently higher in Highs than in Lows. This suggests that time constraints could affect the performance of Highs less than Lows, but also that the two groups could differ in attention capturing mechanisms, i.e. automatic capture by colour at the shorter lag. Moreover, Highs scores on Target identification were lower than Lows' ones indicating an impairment of Highs when engaged in dual tasks.