Abstract
Decades of research have shown that the covert orienting of attention follows a reliable pattern of facilitation then inhibition following a peripheral cue. In this paradigm, observers view a peripheral cue followed by a target at the same or a different location. When the cue-target onset asynchrony (CTOA) is < 200 ms, the cue facilitates target detection at the cued location. However, as the CTOA increases, target detection is inhibited at the cued location. Although this result is well-established, the literature lacks a high resolution spatiotemporal map of this pattern. We conducted a large-scale investigation into charting the spatiotemporal distribution of covert orienting. In addition, we also addressed the inconsistent use of placeholder stimuli in spatial cueing tasks. Attention has a well-known predilection for object contours, so it is problematic that spatial cueing tasks sometimes use placeholder stimuli for cued locations, which should presumably alter the spread of facilitation and attention – and sometimes do not. To remedy this ambiguity, we systematically manipulated the presence of placeholder stimuli at the cue locations. Eighty participants detected targets at 121 possible locations 100 ms, 200 ms, 400 ms, or 800 ms following an uninformative peripheral cue with or without placeholders (see Figure 1A). With placeholders, the classic pattern of early facilitation and late inhibition was observed for targets appearing within the placeholders, and the spread of inhibition is severely limited to within the placeholders (see Figures 1B, 2). Without placeholders, we observed inhibition shortly after cue presentation, upsetting the famously reliable effect of facilitation following a cue. Moreover, inhibition spread from the cued location, unlike when placeholders are present. These findings constitute the most detailed spatiotemporal map of attentional orienting ever recorded, and force a reconsideration of what has become the “classic” distribution of attentional orienting following a peripheral cue.
Meeting abstract presented at VSS 2015