Inhibition of return for expected and unexpected targets

The role of preparation time in the attentional blink

This research investigated the effect of foreperiod predictability in the Attentional Blink (AB). The AB, a cost in processing the second of two targets presented in close temporal proximity, was estimated using a minimalist procedure consisting of two letter targets and two letter fragment masks. In a four-step procedure, differences in foreperiod duration, target exposure duration, and inter-target interval were controlled in order to estimate the AB. Foreperiod was manipulated in three experiments. The AB effect was reduced when a single and relatively long foreperiod value was used (M=880 ms, Experiment 2) in comparison to randomized (250-750 ms, Experiment 1) and single but relatively short foreperiods (M=273 ms, Experiment 3). The results are discussed in the context of resource-sharing and preparation of a perceptual-set pertaining to physical target features including modality and intensity, as well as spatial and temporal predictability. It is concluded that foreperiods that are too brief for an individual observer or temporally unpredictable contribute to the AB.

The involvement of bottom-up saliency processing in endogenous inhibition of return

Participants are faster at detecting a visual target when it appears at a cued, as compared with an uncued, location. In general, a reversal of this cost-benefit pattern is observed after exogenous cuing when the cue-target interval exceeds approximately 250 ms (inhibition of return [IOR]), and not after endogenous cuing. We suggest that, usually, no IOR is found with endogenous cues because no bottom-up saliency-based orienting processes are claimed. Therefore, we developed an endogenous feature-based split-cue task to allow for endogenous saliency-based orienting. IOR was observed in the saliency-driven endogenous cuing condition, and not in the control condition that prevented saliency-based orienting. These results suggest that usage of saliency-based orienting processes in either endogenous or exogenous orienting warrants the appearance of IOR.

Visualizing the temporal dynamics of spatial information processing responsible for the Simon effect and its amplification by inhibition of return

Research has shown that the Simon effect is larger for targets suffering from inhibition of return (IOR). We used speed-accuracy trade-off (SAT) methodology to explore the temporal dynamics underlying this interaction. In Experiment 1, a new method for sorting the data was used to reveal a monotonic decay in the impact of task-irrelevant location information that is responsible for the Simon effect. In Experiment 2, we show that IOR delays both task-relevant identity and task-irrelevant location codes; a relatively longer delay for location than identity codes accounts for the effect of IOR on the Simon effect. When location information was made task-relevant in Experiment 3, IOR delayed the accumulation of this information by about the same amount as when location was irrelevant. The results suggest that IOR, therefore, has a greater effect on location than identity information.

Nonattentional effects of nonpredictive central cues

Recent evidence suggests that nonpredictive gaze, hand, arrow, and peripheral cues elicit shifts of reflexive attention. In the present article, we address whether these cues also influence the decision criterion in a go/no-go task. Nonpredictive central gaze and hand cues pointed toward or away from the location of an imminent target. Responses to the targets were faster, and false alarm errors were more frequent, when cues pointed toward the target than when they were directed away from it. Although a similar pattern was observed with nonpredictive arrow cues, it was not seen with nonpredictive peripheral cues. These results suggest that nonpredictive central cues not only affect attention, but also bias decision processes.

The mechanism underlying inhibition of saccadic return

Human observers take longer to re-direct gaze to a previously fixated location. Although there has been some exploration of the characteristics of inhibition of saccadic return (ISR), the exact mechanisms by which ISR operates are currently unknown. In the framework of accumulation models of response times, in which evidence is integrated over time to a response threshold, ISR could reflect a reduction in the rate of accumulation for saccades to return locations or an increase in the effective criterion for response. In two experiments, participants generated sequences of three saccades, in response to a peripheral or a central cue. ISR occurred across these manipulations: saccade latency was consistently increased for movements to the immediately previously fixated location. Latency distributions from individual observers were fit with a Linear Ballistic Accumulator model. ISR was best accounted for as a change in the accumulation rate. We suggest this parameter represents the overall desirability of a particular course of action, the evidence for which may be derived from a variety of sensory and non-sensory sources.