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Michael D Dodd

Publications and source records attributed to Michael D Dodd.

8 recordsLinked to original sources

Rapid onset and long-term inhibition of return in the multiple cuing paradigm.

Inhibition of return (IOR) refers to the finding that targets at cued locations are responded to more slowly than targets at uncued locations when a relatively long temporal interval occurs between the two events. In studies which have examined the time course of IOR (e.g., Samuel & Kat in Psychonomic Bulletin & Review, 10, 897-906, 2003), the effect is generally shown to develop at around 200 ms and dissipate at around 3,000 ms following a cue. A number of recent studies, however, have demonstrated that IOR can develop much more quickly (up to 50 ms following a cue) and last much longer (up to 13 min following a cue) in certain tasks. The present study uses the multiple cuing paradigm to determine whether IOR can be observed outside the normally reported temporal boundaries (300-3,000 ms) when attention is shifted very quickly (every 15 ms) or very slowly (every 1,500 ms) throughout the visual field. IOR was observed as quickly as 30 ms following cue onset and as long as 6,000 ms following cue onset. Implications for the role of IOR in visual search are discussed.

Cues↗

Re-exposure to studied items at test does not influence false recognition.

In two experiments, we investigated whether re-exposure to previously studied items at test affects false recognition in the DRM paradigm. Furthermore, we examined whether exposure to the critical lure at test influences memory for subsequently presented study items. In Experiment 1, immediately following each studied DRM list, participants were given a recognition test. The tests were constructed such that the number of studied items preceding the critical lure varied from zero to five. Neither false recognition for critical lures nor accurate memory for studied items was affected by this manipulation. In Experiment 2, we replicated this pattern of results under speeded conditions at test. Both experiments confirm that exposure to previously studied items at test does not affect true or false recognition in the DRM paradigm. This pattern strongly suggests that retrieval processes do not influence false recognition in the DRM paradigm.

Analysis of Variance↗

A strategy disruption component to retrieval-induced forgetting.

Retrieval-induced forgetting refers to a paradoxical occurrence wherein the act of remembering some material disrupts the retrieval of other, related material (see, e.g., M. C. Anderson, R. A. Bjork, & E. L. Bjork, 1994). This effect is generally accounted for in terms of inhibitory processes. Across three experiments, we test the inhibitory account of retrieval-induced forgetting, as well as whether there may be a strategy disruption component to the effect. In our first two experiments, we manipulate which items individuals are cued to recall during retrieval practice and demonstrate that retrieval-induced forgetting can be neutralized when those items do not interfere with the individual's retrieval strategy. In the third experiment, we confirm this finding with a different set of stimuli. These results are inconsistent with a purely inhibitory account of retrieval-induced forgetting, and we discuss implications for inhibition theory and strategy disruption in light of these and other findings.

Attention↗

The effect of previous trial type on inhibition of return.

Inhibition of return (IOR) refers to the finding that targets appearing at previously cued locations are more slowly responded to than targets appearing at previously uncued locations when a relatively long temporal interval occurs between the cue and target. This experiment was conducted to determine whether the magnitude of IOR is influenced by the type of preceding trial (cued or uncued) and/or the location of the cue/target on the previous trial. Although no effect of cue/target location is observed, there was a marked effect of previous trial type, as IOR was greater following an uncued trial relative to a cued trial. This effect was attributable to differences in the response time as a function of previous trial type: specifically, participants were faster to respond to cued and uncued trials when the previous trial type was identical.

Attention↗

An illusion of 3-D motion with the Ternus display.

We attempted to eliminate the percept of element motion in the Ternus display by connecting the display elements so that they appeared to be a single object. On each trial, the display elements (two discs) appeared either separated or connected (either via a white line or side by side) and subjects reported whether they observed element motion or group motion at various ISIs. Although it was hypothesized that element motion would be eliminated in the connected condition, subjects observed element motion at short ISIs in the form of a three dimensional illusion in which one element appeared to rotate out in front of (or behind) the other. Implications for short range and long range motion processes are discussed.

Adult↗

False recognition without intentional learning.

Asked to memorize a list of semantically related words, participants often falsely recall or recognize a highly related semantic associate that has not been presented (the critical lure). Does this false memory phenomenon depend on intentional word reading and learning? In Experiment 1, participants performed a color identification task on distractor words from typical false memory lists. In Experiment 2, participants read the same words. In both experiments, the primary task was followed by a surprise recognition test for actually presented and unpresented words, including the critical lures. False alarms to critical lures were robust and quite equivalent across the two experiments. These results are consistent with an activation/monitoring account of false memory, in which processing of semantic associates can evoke false memories even when that processing is incidental.

Color Perception↗

Perceiving numbers causes spatial shifts of attention.

Number symbols are part of our everyday visual world. Here we show that merely looking at numbers causes a shift in covert attention to the left or right side, depending upon the number's magnitude. This observation implies obligatory activation of number meaning and signals a tight coupling of internal and external representations of space.

Attention↗

Inhibition of return with rapid serial shifts of attention: implications for memory and visual search.

Horowitz and Wolfe (2001) suggested that inhibition of return (IOR) should not be observed in tasks that involve rapid deployments of attention. To examine this issue, five of six possible locations were sequentially cued with either short-duration peripheral cues (50 msec) or long-duration peripheral cues (500 msec). As was expected, IOR was observed in the first two experiments at every cued location with the long-duration cues, with the magnitude of IOR decreasing for earlier cued locations relative to later cued locations. In the short-cue condition, IOR was observed at only one cued location (the second to last). The pattern of results for the short-duration cues was found regardless of whether the fixation cue was of a short (Experiment 1) or a long (Experiment 2) duration. In Experiment 3, the final fixation cue was removed, and IOR was again observed at virtually all locations in both the short- and the long-cue conditions. These findings indicate that IOR can be observed at multiple locations when attention is shifted rapidly between locations.

Attention↗