Much is known about attentional switching across space, but much less about switches between nonspatial domains such as category or task. Nonetheless, extensive information about attentional switching in both spatial and nonspatial domains can be found in the experimental literature on a phenomenon known as the attentional blink, in which a switch is required between 2 rapidly sequential targets. If the 2 targets follow one another directly, identification of the second target is almost perfect when no attentional switch is required between the targets or when the switch is unidimensional. In contrast, identification is impaired with switches in location or with multidimensional switches. This pattern of results is consistent with the joint operation of location-specific endogenously controlled input filters and exogenously controlled domain-specific modules. Attentional Switching in Spatial and Nonspatial DomainsAttention can be distributed across space or among nonspatial stimulus attributes such as color, shape, or category. Distribution of attention across space has been studied extensively (see reviews by Kinchla, 1992, & LaBerge, 1990. A major objective of those studies was to discover the rules that govern how quickly, how accurately, and under what conditions the focus of attention can be switched to different regions in space. In contrast, as was pointed out by Allport, Styles, and Hsieh (1994), the study of attentional set in domains other than spatial has been aimed principally at discovering how well a given set can be maintained in the presence of interfering stimuli. Well-known examples are studies of the Stroop effect (reviewed by MacLeod, 1991) and of dual-task interference (reviewed by Pashler, 1998, especially chapter 6). Considerably less work has been done on the dynamics of switching attentional set in nonspatial domains.In studying the dynamics of attentional switching, whether in spatial or nonspatial domains, the main issue is how the cognitive system reconfigures itself to cope with rapidly changing demands

This study surveyed elementary school teachers in Melbourne, Australia to investigate their knowledge about attention-deficit/hyperactivity disorder (ADHD) and its impact on their reported behavior toward and perceptions of children with ADHD. Consistent with previous international findings, teachers demonstrated good overall knowledge about ADHD, with strengths in knowledge of symptoms/diagnosis and weaknesses in knowledge of causes and treatments. To investigate how knowledge impacted reported behaviors and perceptions, teachers also read vignettes of children with ADHD symptoms and rated their reactions to these children. In general, teachers with high, and to some extent average, knowledge about ADHD reported more helpful behaviors (e.g., help-seeking for their students) and perceptions (e.g., perceive the benefit of behavioral and educational treatments). However, teachers with high and average knowledge also predicted that these children would be more disruptive in the classroom, and reported having less confidence in their ability to manage these children. Implications and need for future research are discussed.

When two sequential targets (T1 and T2) are presented within about 600 msec, perception of the second target is impaired. This attentional blink (AB) has been studied by means of two paradigms: rapid serial visual presentation (RSVP), in which targets are embedded in a stream of central distractors, and the two-target paradigm, in which targets are presented eccentrically without distractors. We examined the role of distractors in the AB, using a modified two-target paradigm with a central stream of task-irrelevant distractors. In six experiments, the RSVP stream of distractors substantially impaired identification of both T1 and T2, but only when the distractors shared common characteristics with the targets. Without such commonalities, the distractors had no effect on performance. This points to the subjects' attentional control setting as an important factor in the AB deficit and suggests a conceptual link between the AB and a form of nonspatial contingent capture attributable to distractor processing.

When two targets (Tl and T2) are displayed in rapid succession, accuracy ofT2 identification varies as a function of the temporal lag between the targets (attentional blink, AB). In some studies, performance has been found to be most impaired at Lag I-namely, when T2 followed Tl directly. In other studies, T2 performance at Lag 1 has been virtually unimpaired (Lag 1 sparing). In the present work, we examined how Lag 1 sparing is affected by attentional switches between targets displayed in the same location or in different locations. We found that Lag 1 sparing does not occur when a spatial shift is required between Tl and T2. This suggests that attention cannot be switched to a new location while the system is busy processing another stimulus. The results are explained by a modified version of an attentional gating model