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J A Stolz

Publications and source records attributed to J A Stolz.

11 recordsLinked to original sources
PubMed2001

Disengaging attention: on the locus of the cue-duration effect in partial report.

Increasing cue duration impairs performance in bar-probe partial report when cues are presented peripherally, but not centrally (P. Dixon, R. Gordon, A. Leung, & V. Di Lollo, 1997). Three experiments examined whether this cue-duration effect reflects processes of exogenous attention. The effect of cue duration on partial report performance with peripheral, but not central, cues was replicated (Experiment 1). Further experiments manipulated the degree that exogenous versus endogenous modes of selection were favored and found that the cue-duration effect for peripheral cues was reduced (a) when blocks contained a high proportion of central cues (Experiment 2) and (b) when the color of the cue indicated the location of the target (Experiment 3). These findings challenge the view that the cue-duration effect is restricted to exogenous attention and are discussed in terms of the process of disengaging attention from the cue to reallocate attention to the target representation.

Attention↗
PubMed2001

Taking a bright view of negative priming in the light of dim stimuli: further evidence for memory confusion during episodic retrieval.

A same-different letter-matching task was used to examine the effects of stimulus intensity on negative priming, which is poorer performance when target letters have been presented as distractor letters on the immediately preceding trial. In Experiment 1, stimulus intensity was manipulated between-participants, whereas in Experiment 2, it varied randomly from trial-to-trial within-participants. In Experiment 1, negative priming was equivalent for both stimulus intensities. In Experiment 2, negative priming effects were larger for repeated intensity stimuli than for nonrepeated intensity stimuli, when stimulus intensity was dim. Furthermore, for repeated intensity stimuli, negative priming effects were enhanced when the overt response required to the stimulus was repeated from prime to probe trial. These results are consistent with the hypothesis that negative priming may be due to memory confusion, rather than to inhibition of the distractor stimuli.

Analysis of Variance↗
PubMed2000

Visual word recognition: reattending to the role of spatial attention.

Three experiments examine whether spatial attention and visual word recognition processes operate independently or interactively in a spatially cued lexical-decision task. Participants responded to target strings that had been preceded first by a prime word at fixation and then by an abrupt onset cue either above or below fixation. Targets appeared either in the cued (i.e., valid) or uncued (i.e., invalid) location. The proportion of validly cued trials and the proportion of semantically related prime-target pairs were manipulated independently. It is concluded that spatial attention and visual word recognition processes are best seen as interactive. Spatial attention affects word recognition in 2 distinct ways: (a) it affects the uptake of orthographic information, possibly acting as "glue" to hold letters in their proper places in words, and (b) it (partly) determines whether or not activation from the semantic level feeds down to the lexical level during word recognition.

Adult↗
PubMed2000

Conscious and unconscious influences of memory: temporal dynamics.

Changes in the conscious and unconscious influences of memory over time were assessed in two experiments by using a variant of the process-dissociation procedure. In both experiments, performance on a stem-completion task was measured under both inclusion and exclusion instructions. Across the two experiments, there were four different retention intervals: 2 minutes, 2 days, 2 weeks, and 2 months. The results indicated that conscious influences decreased systematically across retention interval. In contrast, unconscious influences of memory in the absence of conscious influences increased between 2 minutes and 2 days, and then remained relatively stable from 2 days to 2 weeks to 2 months. These results stand in apparent contrast to those of McBride and Dosher (1999), which showed equal rates of forgetting for conscious and unconscious influences of memory on performance. The implications for models of the relation between conscious and unconscious influences of memory on performance are discussed.

Consciousness↗
PubMed1999

Word recognition and temporal order judgments: semantics turns back the clock.

This paper examines the consequences that codes activated during reading have on activities unrelated to reading by investigating the effects of semantics on temporal order judgments. Participants judged which of two word targets appeared first. Targets appeared either synchronously, or were separated by varying stimulus onset asynchronies (SOAs). For one group of participants, one target on each trial was related to a prime word shown at the beginning of the trial. This priming relation affected temporal order judgments such that participants sometimes reported related targets as having appeared first, even when they appeared second. It is suggested that this effect is best explained as showing that codes activated during word recognition affect the attentional selection aspects of the temporal order judgment task.

Attention↗
PubMed1999

What kind of attention modulates the Stroop effect?

An intersection of three literatures (skilled word recognition, spatial attention, and the Stroop effect) is addressed in a series of four experiments. The results, in conjunction with other observations, are taken to suggest that (1) the default value for spatial attention in visual word recognition is distributed across the word, (2) precuing a single letter position serves to narrow the focus of spatial attention, and (3) this reduces or prevents activation in the word recognition system. Consequently, the Stroop effect is reduced in magnitude or eliminated, depending on details of the context. Contrary to the widespread view that it reflects automatic processing, the Stroop effect is better conceptualized as reflecting the action of default settings in the word recognition and attentional systems. Some relations between consciousness, context, and control are noted.

Attention↗
PubMed1999

Unconsciously controlled processing: the Stroop effect reconsidered.

The Stroop effect is widely considered to be compelling evidence that an acquired skill such as reading is "automatic" in the sense that lexical/semantic analyses of single words cannot be prevented, even when they are irrelevant and harmful to the task at hand. This view is challenged by a series of three experiments in which the presence/absence of a Stroop effect depends on (1) whether all of the target elements are colored or not, in conjunction with (2) whether the target and the spatially distinct color word distractor belong to the same domain or not. A framework is offered in which domain-specific encoding algorithms play a major role. Skilled word recognition is typically unconscious, but is characterized better as contextually controlled, rather than "automatic."

Association↗
PubMed1998

Levels of representation in visual word recognition: a dissociation between morphological and semantic processing.

A robust semantic priming effect typically occurs in visual word recognition if the prime is read before a response to the target. However, this effect is dramatically reduced if a letter search is performed on the prime prior to responding to the target. Three lexical decision experiments document the new observation that morphological priming is preserved following letter search on the prime. This dissociation between morphological and semantic priming following letter search can be understood in the context of an interactive activation framework. In addition, the implications of these results for connectionist and compound cue accounts of word recognition, as well as the issue of automaticity in word recognition, are discussed.

Automatism↗
PubMed1996

Exogenous orienting does not reflect an encapsulated set of processes.

It is widely assumed that orienting attention by the use of exogenous cues reflects an encapsulated system impervious to linguistic influence. This view was assessed in 4 experiments in which observers made discriminations between target characters presented above or below fixation. The spatial location of the target was cued by the abrupt onset of a word that was semantically related to a word at fixation on half of the trials and unrelated on the remainder. Responses were significantly faster when target location was validly cued than when it was not. More important, the magnitude of this cuing effect varied as a function of whether the abrupt-onset word cue was semantically related to the fixation word. These results suggest that linguistic processing influences the process of disengagement or movement (or both) from the cued location. Visuospatial attention as reflected in the exogenous-cuing paradigm does not depend on an encapsulated set of processes.

Humans↗
PubMed1995

Measuring the relative magnitude of unconscious influences.

As an alternative to establishing awareness thresholds, stimulus contexts in which there were either greater conscious or greater unconscious influences were defined on the basis of performance on an exclusion task. Target words were presented for brief durations and each target word was followed immediately by its three-letter stem. Subjects were instructed to complete each stem with any word other than the target word. With this task, failures to exclude target words indicate greater unconscious influences, whereas successful exclusion indicates greater conscious influences. Conscious influences were dominant at long durations (e.g., 214 ms), but unconscious influences were dominant at short durations (e.g., 50 ms). Performance on the exclusion task successfully predicted both qualitative differences in Stroop priming and qualitative differences in recognition memory previously associated with the different effects of conscious and unconscious influences. Taken together, these results demonstrate that an exclusion task allows both unconscious and conscious influences to be defined in terms of significant deviations from baseline performance. As such, exclusion tasks provide a method for distinguishing conscious from unconscious influences that does not require establishing thresholds for null awareness.

Adult↗