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M M Chun

Publications and source records attributed to M M Chun.

23 records · Page 2Linked to original sources
PubMed1997

Types and tokens in visual processing: a double dissociation between the attentional blink and repetition blindness.

In rapid serial visual presentation tasks, correct identification of a target triggers a deficit for reporting a 2nd target appearing within 500 ms: an attentional blink (AB). A different phenomenon, termed repetition blindness (RB), refers to a deficit for the 2nd of 2 stimuli that are identical. What is the relationship between these 2 deficits? The present study obtained a double dissociation between AB and RB. AB and RB followed different time courses (Experiments 1 and 4A), increased target-distractor discriminability alleviated AB but not RB (Experiments 2 and 4A), and enhanced episodic distinctiveness of the two targets eliminated RB but not AB (Experiments 3 and 4B). The implications of the double dissociation between AB and RB for theories of visual processing are discussed.

Attention↗
PubMed1997

Temporal binding errors are redistributed by the attentional blink.

When one searches for a target among nontargets appearing in rapid serial visual presentation (RSVP), one's errors in performance typically involve the misreporting of neighboring nontargets. Such illusory conjunctions or intrusion errors are distributed differently around the target, depending on task or stimulus variables. It is shown here that shifts in intrusion error patterns can be produced by the manipulation of attention alone. In a dual-task paradigm, the magnitude and distribution of intrusion errors changed systematically as a function of available attentional resources. Intrusion errors in RSVP tasks reflect internal capacity limitations for binding independent features. The present results support a two-stage model of RSVP target processing.

Adult↗
PubMed1996

Just say no: how are visual searches terminated when there is no target present?

How should a visual search task be terminated when no target is found? Such searches could end after a serial search through all items, but blank trials in many tasks are terminated too quickly for that to be plausible. This paper proposes a solution based on Wolfe's (1994) Guided Search model. The probability that each item is a target is computed in parallel based on items' differences from each other and their similarity to the desired target. This probability is expressed as an activation. Activations are examined in decreasing order until the target is found or until an activation threshold is reached. This threshold is set adaptively by the observer--more conservative following misses, more liberal following successful trials. In addition, observers guess on some trials. The probability of a guess increases as trial duration increases. The model successfully explains blank trial performance. Specific predictions are tested by experiments.

Attention↗
PubMed1995

A two-stage model for multiple target detection in rapid serial visual presentation.

When 2 targets are presented among distractors in rapid serial visual presentation, correct identification of the 1st target results in a deficit for a 2nd target appearing within 200-500 ms. This attentional blink (AB; J.E. Raymond, K.L. Shapiro, & K.M. Arnell, 1992) was examined for categorically defined targets (letters among nonletters) in 7 experiments. AB was obtained for the 2nd letter target among digit distractors (Experiment 1) and also for a 3rd target (Experiment 2). Results of Experiments 3-5 confirmed that AB is triggered by local interference from immediate posttarget stimulation (Raymond et al., 1992) and showed that AB is modulated by the discriminability between the 1st target and the immediately following distractor. Experiments 5-7 further examined the effects of both local interference and global discriminability. A 2-stage model is proposed to account for the AB results.

Adult↗