Stroop and Garner effects in comparative judgment of numerals: The role of attention.

In 7 experiments, participants selected the larger member of pairs of digits that differed in numerical magnitude as well as in physical size. Selective attention to the relevant dimension (number or size) was gauged by Garner and Stroop interference, both of which varied considerably as a function of the number and relative discriminability of values along the constituent dimensions. When the to-be-ignored dimension was more discriminable, sizable Garner and Stroop effects affected performance on the relevant dimension. When it was less discriminable, Garner and Stroop effects were considerably smaller regardless of whether the relevant dimension was numerical or physical size. The sensitivity of Stroop interference to manipulations of discriminability is accounted for by the allocation of attention to the constituent dimensions. The demonstrated malleability of the Stroop effect is incompatible with claims of strong automaticity in numerical processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference and facilitation effects during selective attention: an H215O PET study of Stroop task performance

To investigate the functional anatomy of interference and facilitation during selective attention, we studied 15 normal subjects using the H215O positron emission tomography technique and a computer presented single-trial Stroop task for cognitive activation. Increases in regional cerebral blood flow (rCBF) were observed in a network of structures that have been previously associated with selective attention, including the anterior cingulate gyrus, the frontal polar cortex, the inferior parietal lobule, and the thalamus, as well as the lingual gyrus. Furthermore rCBF decreases (compared to control states) were observed in lateral extra-striate cortex. rCBF changes in prefrontal and extra-striate regions varied with differences in the need to modulate the influence of word and color information while subjects responded to either incongruent or congruent Stroop stimuli. These results indicate the utility of Stroop procedures for investigating the functional anatomy of selective attention. Given recent interest regarding the role of the anterior cingulate gyrus in the pathophysiology of neuropsychiatric disorders, our results also suggest that the Stroop task can serve as a reliable neurobehavioral probe for this region. The significance of these results for understanding processing mechanisms underlying selective attention is discussed within the framework of a parallel distributed processing model of Stroop task performance.     

A confluence of contexts: Asymmetric versus global failures of selective attention to Stroop dimensions.

In 6 experiments probing selective attention through Stroop classification, 4 factors of context were manipulated: (a) psychophysical context, the distinctiveness of values along the color and word dimensions; (b) set size context, the number of stimulus values tested; (c) production context the mode used to respond; and (d) covariate context, the correlation between the dimensions. The psychophysical and production contexts mainly caused an asymmetry in selective attention failure between colors and words, whereas the set size and covariate contexts contributed primarily to the average or global magnitudes of attentional disruption across dimensions. The results suggest that (a) Stroop dimensions are perceptually separable, (b) J. R. Stroop's (1935) classic findings arose from his particular combination of contexts, and (c) stimulus uncertainty and dimensional imbalance are the primary sources of task and congruity effects in the Stroop paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selective and divided attention in a Stroop task.

Three experiments employed a modified version of the Stroop Color-Word Test to document some conditions under which attention may be differentially deployed. Ss were 66 undergraduates. Within limits, Ss chose either to selectively attend to a single stimulus or to distribute processing resources over several stimuli. Thus, attentional strategies may be actively chosen to suit prevailing conditions. Once established, these different modes of attending were themselves differentially open to strategic modulation. (French abstract) (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Stroop task and attention deficits in schizophrenia: A critical evaluation of card and single-trial Stroop methodologies.

The Stroop task, considered by many to be a paradigmatic measure of selective attention, has often been employed to investigate attention deficits in schizophrenia. Card and single-trial versions of this task have yielded different results. In this study both card and single-trial versions were administered to healthy controls (n?=?24) and patients with schizophrenia (n?=?55). No differences in reaction time (RT) interference were found on either version. On the single-trial version, patients showed greater RT facilitation and error rate interference, evidence for a deficit in selective attention. Methodologic and analytic issues that account for the mixed results from earlier card Stroop studies are addressed. It is concluded that single-trial versions provide greater sensitivity to selective attention pathology in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Automaticity and word perception: Evidence from Stroop and Stroop dilution effects.

The Stroop effect is cut in half by adding a neutral word to the display. D. Kahneman and D. Chajczyk's (see record 1984-05774-001) "attention capture" account of "Stroop dilution" holds word recognition to be involuntary but strictly serial. The authors compared attention capture to 3 alternatives involving parallel rather than serial processing: In the lexicon, activation is divided among multiple words; postlexically, multiple words race for access to response processes; or prelexically, feature processing is degraded by multiple patterns whether or not they are words. Results support the latter. Multiple patterns are processed in parallel. If any are color words, Stroop effects occur but are reduced because any color word's input to lexical memory is lower in quality than if a single color word were the only pattern. Thus, lexical encoding is involuntary but can operate on several input representations in parallel, with effectiveness determined by input quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feature-specific effects of selective visual attention

Four experiments were conducted to quantify the effect of performing a foveal discrimination task on sensitivity for a peripheral grating. The observer's primary task was to discriminate either the spatial frequency or orientation of successive foveal Gabor patches. On a third of the trials they also performed a secondary task to detect the presence of a near-threshold grating in the periphery. We find that sensitivity for detection of the peripheral grating depends on the similarity of the spatial frequencies and orientations between the foveal and peripheral stimuli. Importantly, sensitivity is also affected by which feature is being discriminated in the central task. Because the detectability of the peripheral grating is different when different features of the central stimuli are discriminated, we suggest that the effects on sensitivity are due to feature-specific attention and not simply to passive interactions between filters with similar tuning properties.     

The effects of labeling and pointing on children's selective attention.

20 boys and 20 girls at each of 3 grade levels (3rd, 5th, and 7th) were tested in an incidental learning task designed to clarify the role of labeling on children's selective learning. Half the Ss labeled the central stimuli, and half pointed to them as they were exposed. Central learning increased and incidental learning decreased from 3rd to 5th to 7th grade. Labeling facilitated central learning, but pointing did not. Both labeling and pointing reduced incidental learning. Results indicate that labeling has both attention focusing and encoding effects but that the latter are more important for central learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Birth order: Reconciling conflicting effects.

Secular trends in test scores are accurately predicted by trends in aggregate birth orders. The trend data contradict individual-difference analyses that show birth order as a poor predictor of individual test scores. This article demonstrates why the 2 formulations of the problem—the individually distributed birth order analysis and aggregate-pattern analysis—generate different results. A meaningful interpretation is given by the confluence model, a theory specifying the process whereby the intellectual environment modulates intellectual development. The authors introduce the concept of collective potentiation that specifies collective side effects of birth order. In contrast to genetic theories, the confluence model quantifies the differential environmental contributions to intellectual development of successive siblings, and it offers several well-confirmed derivations that genetic and other developmental theories cannot explain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nonstrategic contributions to putatively strategic effects in selective attention tasks.

Proportion compatible manipulations are often used to index strategic processes in selective attention tasks. Here, a subtle confound in proportion compatible manipulations is considered. Specifically, as the proportion of compatible trials increases, the ratio of complete repetitions and complete alternations to partial repetitions increases on compatible trials but decreases on incompatible trials. This confound is demonstrated to lead to an overestimation in the magnitude of the proportion compatible effect in the context of both a Stroop and a Simon task. Implications for previous research and directions for future research using proportion compatible manipulations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evolving conceptions of memory storage, selective attention, and their mutual constraints within the human information-processing system.

The purpose of this review is to formulate a revised model of information processing that takes into account recent research on memory storage, selective attention, effortful versus automatic processing, and the mutual constraints that these areas place on one another. One distinctive aspect of the proposed model is the inclusion of two phases of sensory storage in each modality. The first phase extends sensation of several hundred milliseconds, whereas the second phase is a vivid recollection of sensation. The mechanism of at least the longer phase is the activation of features in long-term memory, comparable to the mechanism of non-sensory, short-term storage. Another distinctive aspect of the model is that habituation/dishabituation and central executive processes together are assumed to determine the focus of attention, without the need for either an early or a late attentional filter. Research issues that contribute to a comparison of models is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of age and task demands on visual selective attention.

We investigated whether young and older adults differ on measures of interference (INT), negative priming (NP), and inhibition of return (IOR) on a spatial selective attention task that gradually increased in cognitive demand, from simple perceptual matching to letter identification. For both groups, INT increased and IOR decreased with task demand; while NP remained stable. We found age-related increases in INT, NP, and IOR, independent of task demand. However, only between-groups differences in IOR remained after correcting for age-related slowing in response times. Finally, we found no association between our measures of attention across groups, suggesting negligible overlap between INT, NP, and IOR. Our results indicate that attention is selectively and independently influenced by age and task demands, with both effects dependent on how attention is measured. These findings shed light on the “frontal hypothesis of aging.” (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrophysiologic indices of Stroop and Garner interference reveal linguistic influences on auditory and visual processing

The purpose of this study was to examine linguistic influences on the auditory and visual processing of words both behaviorally and electrophysiologically. Our task yielded measures of the effect of irrelevant semantic content (Stroop interference) and of the effect of irrelevant linguistic variability (Garner interference). The behavioral results allow us to assess whether the linguistic and nonlinguistic dimensions of verbal stimuli are processed dependently or independently. The electrophysiologic results allow us to determine where any processing interactions are arising, particularly regarding perceptual versus postperceptual underpinnings, and to evaluate the similarity and dissimilarity between the two interference effects. Results show pronounced Stroop and Garner interference both behaviorally and electrophysiologically, indicating linguistic influences on auditory and visual processing. Subjects could not ignore the irrelevant linguistic dimension and attend selectively to the physical dimension of either spoken or written words. The results indicate that the physical and linguistic dimensions of words are not processed independently. With regard to the stage of processing underlying the interference effects, our results suggest that both Stroop and Garner interference involve multiple stages of processing. The two interference effects are not duplicate measures, however, and different electrophysiologic signatures were observed. Stroop interference is characterized by perceptual and postperceptual components. Similar electrophysiologic patterns within the auditory and visual modalities suggest that each interference effect is tapping similar processes for spoken and written stimuli.     

Garner and congruence effects in the speeded classification of bimodal signals.

The role of attention in speeded Garner classification of concurrently presented auditory and visual signals was examined in 4 experiments. Within-trial interference (i.e., congruence effects) occurred regardless of the attentional demands of the task. Between-trials interference (i.e., Garner interference) occurred only under conditions of divided attention when making judgments about auditory signals. Of importance, the data show congruence effects in the absence of Garner interference. Such a pattern has been rarely reported in studies of the classification of purely visual stimuli and contradicts theoretical accounts asserting that the effects share a common locus. The data question the notion that Garner classification reveals fundamental insights about the nature of the perceptual processing of bimodal stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference effects in the Stroop and Simon paradigms.

The possibility that Stroop and Simon effects reflect the same cognitive processes was tested in 3 experiments with 62 adult Ss. The words LEFT and RIGHT were shown left and right of screen center. Similar levels of interference were found for a Simon task (keypress to meaning of word) and a spatial Stroop task (name its location). A reverse Simon task (keypress to word location) showed minimal interference from the irrelevant word, but in a reverse spatial Stroop task (read the word aloud) interference from the irrelevant location was sizeable. This poses difficulty for translational accounts of Stroop interference. Presenting LEFT and RIGHT laterally balanced by a color-name foil yielded a Simon effect inconsistent with an orienting response hypothesis. With bilateral stimuli in a reverse Simon task, interference was marked, supporting an integrative account of Stroop and Simon effects in terms of cognitive activation and the salience of irrelevant stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Levels of processing and selective attention effects on encoding in memory

The purpose of the present study was to investigate the effects of selective attention and levels of processing (LOPs) at study on long-term repetition priming vis-a-vis their effects on explicit recognition. In a series of three experiments we found parallel effects of LOP and attention on long-term repetition priming and recognition performance when the manipulation of these factors at encoding was blocked. When a mixed study condition was used, both factors affected explicit recognition, while their effect on repetition priming was determined by the nature of the test. Shallow processing at test did not benefit from long-term repetition, regardless of whether the words had been studied deeply or shallowly. Selective attention affected long-term repetition priming in a semantic, but not in a lexical decision (LD), test. Regardless of study condition, retention lag affected long-term repetition priming only in the semantic test. These results suggest that if the experimental conditions allow scrupulous selection of attended and unattended information or narrow tuning to a shallow, pre-lexical LOP, implicit access to unattended or shallowly studied items is significantly reduced, as is explicit recognition. We suggest a conceptual framework for understanding the effects of LOP, attention, and retention interval on performance of explicit and implicit tests of memory.     

Multidimensional psychophysics and selective attention in animals.

Notes that the hypothesis that animals selectively attend developed mainly in explanations of certain conditioning and discrimination learning phenomena. This hypothesis of selective attention is evaluated against a continuity (nonattentional) theory, and most, if not all, facts of simple learning can be accounted for by a nonattentional analysis. Thus, the usefulness of selective attention as an explanatory notion remains in doubt, and few phenomena can be regarded as exemplars of selective attention. In contrast, many examples of selective attention phenomena have been discovered in human information processing experiments. Emphasis in these experiments is on instructional and stimulus variables as they affect steady-state performance rather than response learning. Recent research with animals, modeled on human steady-state tasks, promises to provide similar instances of selective attention effects in performance. (2 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Probability matching in visual selective attention.

J. Jonides (see record 1981-22746-001) suggested a model to account for shifts of spatial attention in visual search tasks with less than 100% cue validity. This 2-stage probability matching model was subsequently tested by Jonides (see record 1984-08558-001). Reaction time (RT) distribution characteristics provided some support for the model. The present author reanalyzes Jonides's data (including that published in 1981). Analysis showed strong support for the probability matching hypothesis. It is concluded that probability matching is an important strategic characteristic of visual spatial attention. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related decrement in auditory selective attention.

Young (n?=?30), middle-aged (n?=?32), and old (n?=?28) adults repeated (shadowed) words presented to the left ear at 60 words per minute with and without distracter words presented to the other ear. Dichotic shadowing error rate increased with age. An attempt to eliminate the age effect by adjusting for age differences in monaural shadowing errors, fluid intelligence, and pure-tone hearing loss did not succeed. When the analyses were confined to Ss who made no monaural shadowing errors, dichotic shadowing errors still increased linearly with age. These results showed that there are selective-attention deficits in older adults that cannot be accounted for by the uncertainty of the target location. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Capture of attention in selective frequency listening.

Four signal-detection experiments demonstrated robust stimulus-driven, or exogenous, attentional processes in selective frequency listening. Detection of just-above-threshold signal tones was consistently better when the signal matched the frequency of an uninformative cue tone, even with relatively long cue-signal delays (Experiment 1) or when as few as 1 in 8 signals were at the cued frequency (Experiment 2). Experiments 3 and 4 compared performance with informative and uninformative cues. The involvement of intentional, or endogenous, processes was found to only slightly increase the size of the cuing effect beyond that evident with solely exogenous processes, although the attention band, a measure of how narrowly attention is focused, was found to be wider when cues were informative. The implications for models of auditory attention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)