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1.
Visual attention research has revealed that attentional allocation can occur in space- and/or object-based coordinates. Using the direct and elegant design of R. Egly, J. Driver, and R. Rafal (1994), the present experiments tested whether space- and object-based inhibition of return (IOR) emerge under similar time courses. The experiments were capable of isolating both space- and object-based effects induced by peripheral and back-to-center cues. The results generally support the contention that spatially nonpredictive cues are effective in producing space-based IOR at a variety of stimulus onset asynchronies (SOAs) and under a variety of stimulus conditions. Whether facilitatory or inhibitory in direction, the object-based effects occurred over a very different time course than did the space-based effects. Reliable object-based IOR was only found under limited conditions and was tied to the time since the most recent cue (peripheral or central). The finding that object-based effects are generally determined by SOA from the most recent cue may help to resolve discrepancies in the IOR literature. These findings also have implications for the search facilitator role that IOR is purported to play in the guidance of visual attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
The present experiments tested whether endogenous and exogenous cues produce separate effects on target processing. In Experiment 1, participants discriminated whether an arrow presented left or right of fixation pointed to the left or right. For 1 group, the arrow was preceded by a peripheral noninformative cue. For the other group, the arrow was preceded by a central, symbolic, informative cue. The 2 types of cues modulated the spatial Stroop effect in opposite ways, with endogenous cues producing larger spatial Stroop effects for valid trials and exogenous cues producing smaller spatial Stroop effects for valid trials. In Experiments 2A and 2B, the influence of peripheral noninformative and peripheral informative cues on the spatial Stroop effect was directly compared. The spatial Stroop effect was smaller for valid than for invalid trials for both types of cues. These results point to a distinction between the influence of central and peripheral attentional cues on performance and are not consistent with a unitary view of endogenous and exogenous attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
It is still unclear whether impairments in visuospatial processing in children with developmental coordination disorder (DCD) are a consequence of their motor deficits or are independent of them. In two experiments, 20 children with DCD and 20 matched controls were tested on the covert orienting of a visuospatial attention task (COVAT). Experiment 1 used a COVAT with peripheral cues and an 80% probability that targets would appear at the cued location. While the results suggested a deficit in the disengage operation of orienting covert attention for the DCD group, they were difficult to reconcile with models of covert orienting and the results of past research. Experiment 2 tested subjects on two new versions of the COVAT: the first used peripheral cues and no probability information (exogenous mode), and the second used central cues and an 80% probability that targets would appear at the cued location (endogenous mode). The DCD group displayed attentional orienting deficits only for the endogenous mode. These results suggest that impairments in the endogenous control of visuospatial attention are independent of motor deficits in DCD.  相似文献   

4.
Previous studies of covert orienting in Alzheimer's disease (AD) have investigated exogenous and endogenous processes separately. We aimed to investigate how the 2 modes of orienting interact to control attention in healthy older participants and patients with AD. The covert orienting of visual attention task (COVAT) with abrupt onset cues was used in all experiments. In Experiments 1 and 2, predictive information was added to cues to initiate an endogenous orienting response. Results showed that healthy older participants were able to use endogenous processes to inhibit exogenous orienting. In contrast, patients with AD were unable to inhibit exogenous orienting to cues even when targets rarely appeared there. Experiment 3 investigated inhibition of return (IOR) in patients with AD. Both healthy older controls and patients with AD showed a normal IOR, suggesting that exogenous orienting processes are relatively unaffected by the normal aging process or in patients with AD. A model of covert orienting in which exogenous and endogenous orienting processes interact to control attentional behaviors is discussed.  相似文献   

5.
The relation between reflexive and voluntary orienting of visual attention was investigated with 4 experiments: a simple detection task, a localization task, a saccade toward the target task, and a target identification task in which discrimination difficulty was manipulated. Endogenous and exogenous orienting cues were presented in each trial and their validity was manipulated orthogonally to examine whether attention mechanisms are mediated by separate systems and whether they have additive and independent effects on visual detection and discrimination. The results showed that each orienting mechanism developed its typical and independent effect in every case except for the difficult identification task. A theoretical framework for understanding the relationship between endogenous and exogenous orienting of attention is proposed, tested, and confirmed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
Orienting to an uninformative peripheral cue is characterized by a brief facilitation followed by a long-lasting inhibition once attention is removed from the cued location. Although central gaze cues cause reflexive orienting, the inhibitory effect that is relatively ubiquitous following exogenous orienting to uninformative peripheral cues has been relatively rare. We hypothesized that IOR might be seen following gaze-induced orienting if attention were effectively returned to centre by a return gaze or return flash. The timecourse of gaze-directed orienting was measured by varying the interval between the gaze cue and a peripheral target requiring an orientation discrimination (permitting measurement of the Simon effect). Significant facilitation was observed at all but the longest SOA tested, 2,880 ms, by which time the facilitation had disappeared with no evidence of IOR. Gaze-induced cuing (which was unaffected by return cue condition) interacted with the Simon effect, decreasing it at the gazed-at location, a pattern that is not seen with more typical endogenous and exogenous cuing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Objective: While attentional functions are usually found to be impaired in schizophrenia, a review of the literature on the orienting of spatial attention in schizophrenia suggested that voluntary attentional orienting in response to a valid cue might be paradoxically enhanced. We tested this hypothesis with orienting tasks involving the cued detection of a laterally presented target stimulus. Method: Subjects were chronic schizophrenia patients (SZ) and matched healthy control subjects (HC). In Experiment 1 (15 SZ, 16 HC), cues were endogenous (arrows) and could be valid (100% predictive) or neutral with respect to the subsequent target position. In Experiment 2 (16 SZ, 16 HC), subjects performed a standard orienting task with unpredictive exogenous cues (brightening of the target boxes). Results: In Experiment 1, SZ showed a larger attentional facilitation effect on reaction time than HC. In Experiment 2, no clear sign of enhanced attentional facilitation was found in SZ. Conclusions: The voluntary, facilitatory shifting of spatial attention may be relatively enhanced in individuals with schizophrenia in comparison to healthy individuals. This effect bears resemblance to other relative enhancements of information processing in schizophrenia such as saccade speed and semantic priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
This study investigated whether impaired endogenous attention and enhanced exogenous attention for the processing of nonemotional stimuli were observed in individuals with high social anxiety. In each trial, participants were presented with an endogenous cue at a center, followed by exogenous cues at peripheral locations; subsequently, nonemotional masked targets were presented wherein the subjects were asked to distinguish between the targets. The accuracy rates were influenced by social anxiety only in exogenous conditions. Individuals with high social anxiety exhibited higher accuracy in the valid condition than in the invalid condition of exogenous attention, whereas individuals with low social anxiety displayed uniform accuracy rates in valid, neutral, and invalid conditions. The validity effects in individuals with high social anxiety did not diminish when controlling for trait and state anxiety and depression. The results suggest that individuals with high social anxiety have an enhanced exogenous attentional system and that they are attracted to salient stimuli regardless of emotionality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
An early interest in cognitive processes led me to study with Mike Posner from whom I acquired the intellectual tools to follow Hebb’s (1949) advice that “Everyone knows that attention and set exist so we had better get the skeleton out of the closet and see what can be done with it.” Using variants of the model task Posner developed for exploring the control of visual attention we have demonstrated that endogenous shifts of attention are not generated by unexecuted oculomotor activation, that endogenous and exogenous shifts of attention are fundamentally different on a variety of dimensions and that an aftermath of exogenous (but not endogenous) orienting, inhibition of return, facilitates search by encouraging orienting to novel items. A research strategy for understanding ambiguous forms of orienting (e.g., that controlled by conspecific gaze) is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
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 (1) when blocks contained a high proportion of central cues (Experiment 2) and (2) 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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
Visual spatial attention can be exogenously captured by a salient stimulus or can be endogenously allocated by voluntary effort. Whether these two attention modes serve distinctive functions is debated, but for processing of single targets the literature suggests superiority of exogenous attention (it is faster acting and serves more functions). We report that endogenous attention uniquely contributes to processing of multiple targets. For speeded visual discrimination, response times are faster for multiple redundant targets than for single targets because of probability summation and/or signal integration. This redundancy gain was unaffected when attention was exogenously diverted from the targets but was completely eliminated when attention was endogenously diverted. This was not a result of weaker manipulation of exogenous attention because our exogenous and endogenous cues similarly affected overall response times. Thus, whereas exogenous attention is superior for processing single targets, endogenous attention plays a unique role in allocating resources crucial for rapid concurrent processing of multiple targets. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

12.
In the present study we investigated whether the visually allocated "beam" studied by Posner and others is the same visual attentional resource that performs the role of feature integration in Treisman's model. Subjects were cued to attend to a certain spatial location by a visual cue, and performance at expected and unexpected stimulus locations was compared. Subjects searched for a target letter (R) with distractor letters that either could give rise to illusory conjunctions (PQ) or could not (PB). Results from three separate experiments showed that orienting attention in response to central cues (endogenous orienting) showed similar effects for both conjunction and feature search. However, when attention was oriented with peripheral visual cues (exogenous orienting), conjunction search showed larger effects of attention than did feature search. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
Previous research has shown that visual attention can be directed to a spatial location in 2 qualitatively different ways. Attention can be allocated endogenously in response to centrally presented precues, or it can be captured exogenously by a visual stimulus with an abrupt onset. It has been suggested that exogenous orienting of attention is an automatic process, whereas endogenous orienting of attention represents a controlled and strategic process. M.I. Posner and C.R.R. Snyder (1975) suggested that an automatic process occurs without intention, does not interfere with other mental processes, and does not necessarily give rise to awareness, whereas a controlled process will likely interfere with other processes and necessarily requires intention and awareness. Three experiments investigated the role of awareness in orienting visual attention. Endogenous and exogenous components of orienting attention were placed in opposition to each other to assess the automaticity of exogenous orienting by examining the potential for brief stimulus events to capture attention in the absence of subjective awareness. Results show that an exogenous cue presented below a subjective threshold of awareness captured attention automatically and without awareness.  相似文献   

14.
The authors investigated 2 effects of object-based attention: the spread of attention within an attended object and the prioritization of search across possible target locations within an attended object. Participants performed a flanker task in which the location of the task-relevant target was fixed and known to participants. A spreading attention account predicts that object-based attention will arise from the spread of attention through an attended object. A prioritization account predicts that there will be a small, if any, object-based effect because the location of the target is known in advance and objects are not required to prioritize the deployment of attentional search. The results suggested that object-based attention operates via the spread of attention within an object. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
In this experiment, a Stroop-like paradigm was used to investigate the ability to attend to visuospatial cues while ignoring distracting stimuli in the auditory or visual modality. In Part 1, the authors investigated whether linguistic cue words (i.e., RIGHT, LEFT, DOWN, and UP) would induce endogenous shifts of attention to visual targets. In Part 2, a relevant distractor stimulus was introduced in a different modality from the endogenous cues to investigate effects of interference. Twenty-five right-handed students served as participants. Auditory and visual linguistic cues were effective in inducing shifts of visual attention when cues were presented alone. Furthermore, introducing a distractor stimulus decreased the efficacy of these cues differently depending on modality, suggesting that language processing and visuospatial attention may share neuronal resources. Implications for unimodal and supramodal mechanisms of selective attention and relevant neuronal networks are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
There is considerable evidence that overlearned symbols, especially arrows, can orient attention to peripheral locations. In 2003, Pratt and Hommel showed that when 1 arrow is selected from a set of arrows, based on an attentional control setting for a specific target color, the selected arrow determines the orientation of attention. Recently, Leblanc and Jolicoeur (2010) reexamined this finding, and concluded that spatial proximity of the arrow to the target, not the symbolic value of the arrow, determines the orienting of attention. Here, we manipulated both the symbolic value of the cue (direction arrows or directionless circles) and the proximity of the cue to the peripheral target location (near or far), and found that although proximity does play a role in the orienting of attention (larger cuing effects were found with far cues than near cues), the symbolic content of the cue also plays an important role (larger cuing effects were found with arrows than circles). Thus, both the symbolic value and the spatial proximity of cues affect the orienting of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
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)  相似文献   

18.
1. While the effects of benzodiazepines on human memory have been extensively studied little is known about the effects of these agents on attentional processes. The authors studied the effects of a single dose of triazolam on selective visual-spatial attention using a double blind, placebo controlled design. 2. In each of 2 sessions 12 normal volunteers ingested either 0.25 mg of triazolam or placebo. Attentional performance was evaluated using two versions of the covert orienting paradigm which measured automatic (exogenous) and controlled (endogenous) aspects of attentional orienting, respectively. 3. Triazolam selectively modified performance on automatic orienting to exogenous cues. Specifically, triazolam increased the facilitation of target detection seen at shorter (150 msec) SOA's. This may indicate an increase in facilitation and a reduction in inhibition or a slowing of the time course of the biphasic attentional effect normally resulting from exogenous cuing. 4. These results indicate the importance of using experimental paradigms which effectively dissociate endogenous and exogenous mechanisms of spatial orienting in studies evaluating the effects of pharmacological agents on visual-spatial attention.  相似文献   

19.
Two experiments were conducted to examine whether abrupt onsets are capable of reflexively capturing attention when they occur outside the current focus of spatial attention, as would be expected if exogenous orienting operates in a truly automatic fashion. The authors established a highly focused attentional state by means of the central presentation of a stream of visual or auditory characters, which participants sometimes had to monitor. No intramodal reflexive cuing effects were observed in either audition or vision when participants performed either an exogenous visual or auditory orthogonal cuing task together with the central focused attention task. These results suggest that reflexive unimodal orienting is not truly automatic. The fact that cuing effects were eliminated under both unimodal and cross-modal conditions is consistent with the view that auditory and visual reflexive spatial orienting are controlled by a common underlying neural substrate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
Drug motivation models postulate that attention biasing toward smoking-related cues is a cognitive mechanism supporting continued or renewed drug use, and they predict that drug use history, deprivation, and distress should modulate the extent of this bias. The present study used the modified Stroop paradigm to extend past research regarding attention biasing toward smoking and unpleasant, pleasant, and neutral words among adult nonsmokers and daily smokers. Both nonsmokers and smokers showed differential attention toward unpleasant and pleasant cues, particularly pleasant cues, but did not show a unique bias toward smoking-related stimuli. Results suggested that, among smokers, nicotine deprivation and exogenous stress (threat of electric shock) have a nonadditive effect on attention toward pleasant cues but no effect on attention to smoking cues specifically. Similarly, instructing smokers that they would have an opportunity to smoke did not significantly increase the bias of nicotine-deprived smokers' attention toward smoking-related cues, relative to arousing unpleasant and pleasant cues. Overall, results suggest that smokers' attention may be biased toward both smoking-related and other salient cues when deprived of nicotine and anticipating an opportunity to smoke. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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