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W T Neill

Publications and source records attributed to W T Neill.

10 recordsLinked to original sources
PubMed2000

Information processing and PTSD: a review of the empirical literature.

This article reviews a series of studies that have utilized information-processing paradigms with posttraumatic stress disorder (PTSD) populations. The review suggests that pretrauma measures of intelligence (IQ) are predictive of the development of PTSD symptoms following trauma. There is also evidence of impaired performance on standardized tests of memory (independent of IQ) in PTSD populations. PTSD populations are found to exhibit deficits in memory function that may be due to hippocampus damage secondary to excessive neuroendocrine responses to conditioned stimuli. In addition, individuals with PTSD evince an attentional bias towards trauma-related stimuli at postrecognition stages of information processing. The review also includes that there is insufficient evidence to either support, or reject, the theoretical proposition that PTSD patients are sensitive to global valence effects at the earliest stages of information processing relative to traumatized non-PTSD populations. Finally, there is some evidence to suggest that the processes associated with autobiographical memory in PTSD populations are similar to those seen in depression. The implications of these findings for the behavioral and cognitive treatment of PTSD are discussed. Directions for future research with such paradigms are also discussed in light of contemporary information processing theories of PTSD.

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PubMed2000

Novel popout and familiar popout in a brightness discrimination task.

A single novel word among several familiarized words may be localized more effectively than the familiarized words (novel popout). Early demonstrations of novel popout attributed the effect to the capture of attentional resources by novel stimuli. Christie and Klein (1995, 1996) argued that differential recollection of novel versus familiar words could alternatively account for the popout effect. In the present experiments, participants judged which of four locations contained a physically brighter word. A bright novel word was localized significantly better than a bright familiar word in one-novel/three-familiar arrays, inconsistent with a retrievability account of novel popout. However, a bright familiar word was also localized better than a bright novel word in three-novel/one-familiar arrays, inconsistent with the mismatch theory proposed by Johnston and Hawley (1994). The results suggest that familiarity and novelty provide a perceptual segregation of the odd item; superior brightness discrimination at that location may be due either to attentional capture or to locational ambiguity within the larger group.

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PubMed1999

Response conflict reverses priming: a replication.

Subjects named target words that followed a masked prime word of 33-msec (Experiments 1A and 1B) or 200-msec (Experiment 2) duration. The target word was either presented alone or accompanied by an interleaved distractor word. Targets presented alone were named more quickly following an identical prime than following an unrelated prime (repetition priming). In Experiment 1A, targets with distractors were named more slowly following an identical prime than following an unrelated prime (negative priming), replicating Milliken, Joordens, Merikle, and Seiffert (Psychological Review, 1998). In Experiments 1B and 2, repetition priming was reduced, although not reversed, for targets with distractors. The results of all three experiments are opposite to the usual finding of enhanced priming for perceptually degraded targets and suggest that response conflict engages retrospective mechanisms that counteract the facilitatory effects of priming.

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PubMed1998

Novel popout without novelty.

Localization of a novel word in an array with several familiar words is typically enhanced relative to localization in an all-novel array (between-array novel popout) and sometimes enhanced relative to familiar words in one-novel arrays (within-array novel popout). Christie and Klein (1996) have questioned the reality of the latter effect, suggesting that it may be an artifact of guessing bias. The present Experiment 1 replicated within-array novel popout with the novel word probed at chance (i.e., on only one quarter of trials). Experiments 2 and 3 demonstrated a similar popout effect for a categorically unrelated word among three categorically related words, despite superior performance on all-related arrays relative to all-unrelated arrays. Repetition of constant sets of words within the experimental context is therefore unnecessary for a popout effect, contrary to assertions by Johnston and Hawley (1994). Interitem associations appear to be sufficient to produce a popout effect; as such, "novel popout" appears to be a misnomer for a phenomenon that does not depend on novelty.

Adult↗
PubMed1994

Does "inhibition of return" occur in discrimination tasks?

When attention is drawn to a location and then withdrawn, responding to a stimulus at that location may be slower than to one at a new location. This "inhibition of return" (IOR) has not been reliably demonstrated in tasks that require discrimination of targets from nontargets. The present experiments replicated IOR in detection and localization tasks only when target/non-target discrimination was not also required. When discrimination was required, a consistent same-location advantage occurred for repeated targets. Changed targets may, however, induce a bias toward opposite responses. The results cast doubt on IOR as a general attentional phenomenon.

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PubMed1992

Persistence of negative priming: II. Evidence for episodic trace retrieval.

Responses to recently ignored stimuli may be slower or less accurate than to new stimuli. This negative priming effect decays over time when delay is randomized within subjects, but not when delay varies between subjects. In Experiment 1, response-stimulus intervals (RSI) of 500 and 4,000 ms were randomized within subjects in a target localization task. Negative priming of ignored locations diminished with longer delay. However, no significant decay was obtained when RSI and the preceding RSI were equal. Similar results were obtained when RSI and preceding RSI were deliberately confounded by blocking (Experiment 2). Negative priming appears to depend on temporal discriminability of the priming episode.

Adult↗
PubMed1990

Negative priming in same-different matching: further evidence for a central locus of inhibition.

Responses to recently ignored information may be slower or less accurate than responses to information not recently encountered. Such negative priming effects imply that the mechanism of selective attention operates on unattended, as well as attended, information. In the present experiment, subjects judged the second and fourth letters of five-letter strings (e.g., BABAB) as "same" or "different." Responses were slower when a target letter was identical to the distractors presented in the immediately preceding trial. This effect did not depend on which response was required on the current or preceding trial. The results suggest that ignored information is functionally disconnected from the response system as a whole, rather than from a specific response.

Adult↗