Temporal allocation of visual attention in adult attention deficit hyperactivity disorder

In two experiments, we examined the ability of adults with attention defici t hyperactivity disorder (ADHD) to process multiple targets appearing in a rapid serial visual presentation (RSVP) stream. Using a standard attentiona l blink (AB) task, subjects were required to both identify a target in the RSVP stream and detect a probe appearing in one of several posttarget seria l positions. In Experiment 1, ADHD adults exhibited a protracted AB compare d to controls, in that their probe detection did not improve as a function of increasing probe-to-target intervals (450-720 msec). In Experiment 2, th e ADHD group performed as well as controls in detecting probes appearing im mediately (i.e., 90 msec) after the target. Taken together, the results dem onstrate that adults with ADHD exhibit a selective deficit in rapidly shift ing attention between the target and the probe, when the two appear several hundred milliseconds apart. These results suggest that adults with ADHD ca n use automatic (reflexive) attention to detect items in close temporal pro ximity in the RSVP stream, but have difficulty allocating controlled attent ion to multiple stimuli separated by several hundred milliseconds.