Effect of benzodiazepine on temporal integration in object perception.
BACKGROUND
Though various psychometrical tests indicate that benzodiazepines affect vigilance, few studies have been conducted to assess the effect of benzodiazepines on attentional processes.


OBJECTIVE
We used a RSVP (Rapid Serial Visual Presentation) procedure to investigate the effect of benzodiazepines on the attentional blink effect. It refers to the difficulty in detecting a probe following identification of a target within a temporal window of 500 ms.


METHODS
Three experimental groups were tested (placebo, lorazepam and diazepam). Sequences of 15 pictures were centrally displayed for 50 ms each. In a dual-task condition, observers were instructed (1) to identify the target (the single picture on a blue background) and (2) to detect the presence of a probe. In the single-task condition, subjects were asked to detect the probe. The serial position of the probe relative to the target was varied.


RESULTS
Performance was equivalent for the three groups in the single-task condition. In the dual-task condition, the attentional blink was increased in magnitude and duration for benzodiazepine-treated subjects, especially diazepam, than for placebo-treated subjects. A large number of intrusions (a tendency to report as target the name of a picture preceding the target) were observed in the benzodiazepine-treated groups.


CONCLUSIONS
The results indicate that benzodiazepines impair visual integration in the temporal domain. This extends previous findings that benzodiazepine impairs visual integration in the spatial domain. The results also suggest that benzodiazepine increase time to disengage attention from a first to a second target.
Boucart
M
M
Laboratoire de Neuroscience du Comportement, Université Lille 1, Villeneuve d'Ascq, France. muriel.boucart@univ-lille1.fr
de Visme
P
P
Wagemans
J
J
D000293:Adolescent; D000328:Adult; D001288:Attention / Q000187:drug effects*; D001569:Benzodiazepines / Q000494:pharmacology*; D003975:Diazepam / Q000494:pharmacology; D004311:Double-Blind Method; D006801:Humans; D008140:Lorazepam / Q000494:pharmacology; D010465:Perception
D001569:Benzodiazepines; D008140:Lorazepam; D003975:Diazepam