Temporal limitations of information processing in global and local attention: the effect of information content

The refractory period during which detection or identification of a probe is degraded, following the successful visual identification of a target, is referred to as the attentional blink (AB). Previous work in this laboratory using global/local letter forms has shown that the degree of complexity of information influences the length of time between successful visual identifications, as does the attentional modality required of the subject. In the standard rapid serial visual presentation (RSVP) task, a gap following the first target is reported to destroy the AB. The current study examines the effect on the AB duration of inserting a gap in the stream of local orthographic information while not interrupting the stream of global information. It was hypothesized that masking of the local elements of the item immediately following the target (the +1 item) would lead to a decreased AB duration for local identification.

Twenty-one adult participants, experienced in the experimental paradigm, viewed sequences of compound letter stimuli and were required to identify a global or local red letter (target) and detect the presence of a global or local X (probe) in the sequence following.

In one-half of the trials the local letter identity of the +1 global/local form was obscured, leaving only a global form. Neither the attentional condition nor local +1 masking significantly influenced the slope of recovery from the AB. Furthermore, no difference was observed in the AB duration for global or local probe detection between control and crystallized trials.

The results suggest that the visual image of the item is accepted nto VSTM and processed for target candidature.