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Previous studies have separately found that exogenous orienting decreases multisensory integration (MSI), while endogenous orienting enhances MSI. It is currently unclear, however, why the two orientations have opposite effects on MSI. In the current study, we investigated the interaction between spatial attention and MSI in two experiments based on the cue–target paradigm. Experiment 1 separated exogenous and endogenous orienting to investigate the effect of spatial attention on MSI by varying the predictability of the cue. Experiment 2 further explored the effect of endogenous orienting on MSI. We found that exogenous orienting induced by the directionality of the cue decreased MSI, while endogenous orienting induced by the predictability of the cue enhanced MSI. The role of spatial orienting need and spatial attention bias in the modulation of MSI by exogenous and endogenous orienting was discussed. The present study sheds new light on how spatial attention modulates MSI processes. [ABSTRACT FROM AUTHOR]

People shift their attention in the direction of another person's gaze.This phenomenon, called gaze cuing, shares properties with purely endogenous (i.e., "deliberate") and purely exogenous (i.e., "reflexive") control of spatial attention. For example, as with purely endogenous orienting, gaze cues appear at visual fixation; yet, as with purely exogenous orienting, gaze cues elicit shifts of attention rapidly after their appearance. Prior experiments have shown that when controlled endogenously versus exogenously, the effects of attention upon the processing of targets are dramatically different. Briand and Klein (1987; see also Briand, 1998) showed that endogenous orienting is additive with opportunities for illusory conjunctions, whereas exogenous orienting is interactive. Klein (1994) showed that endogenous orienting is interactive with nonspatial expectancies,whereas exogenous orienting is additive. In the present project, we applied this double-dissociation strategy to attention controlled by gaze cues. In Experiment 1, gaze cuing effects (in accuracy) were additive with opportunities for illusory conjunctions (akin to endogenous control), whereas in Experiment 2, gaze cuing was additive with the nonspatial expectancy effect (akin to exogenous orienting). Therefore, in the nature of its effects upon performance, gaze cuing functions like a hybrid of endogenous and exogenous orienting. [ABSTRACT FROM AUTHOR]

The literature has long emphasized the neocortex’s role in volitionalprocesses. In this work, we examined endogenous orienting in anevolutionarily older species, the archer fish, which lacks neocortex-like cells. We used Posner’s classic endogenous cuing task, in whicha centrally presented, spatially informative cue is followed by a tar-get. The fish responded to the target by shooting a stream of waterat it. Interestingly, the fish demonstrated a human-like “volitional”facilitation effect: their reaction times to targets that appeared onthe side indicated by the precue were faster than their reactiontimes to targets on the opposite side. The fish also exhibited inhi-bition of return, an aftermath of orienting that commonly emergesonly in reflexive orienting tasks in human participants. We believethat this pattern demonstrates the acquisition of an arbitrary con-nection between spatial orienting and a nonspatial feature of acentrally presented stimulus in nonprimate species. In the literatureon human attention, orienting in response to such contingencies hasbeen strongly associated with volitional control. We discuss theimplications of these results for the evolution of orienting, and forthe study of volitional processes in all species, including humans.

A new variation of the Attention Network Task (ANT) was designed to measure the functioning of and interactions between the alerting, exogenous and endogenous visual spatial orienting, and executive control systems in young school children. Previous research has produced mixed results regarding typical functioning of the attention networks in six-year-olds; no ANT has measured the functioning of the endogenous network. This Staged ANT tested the Alerting, Exogenous, and Endogenous orienting networks in separate conditions. Two hundred and forty-seven children (average age 6 years, 103 girls) completed the task. There was no clear benefit of the alerting cue until the spatial orienting cues were introduced into the task, suggesting task complexity was needed before alerting benefits were observed. The validity effect of the exogenous cue was very strong: in contrast, the validity effect of the endogenous cue was very weak. The flanker effect was very strong. A benefit of the alerting cue was shown during both the exogenous and endogenous conditions, while a cost of the alerting cue was shown during the invalid exogenous trials. Neither the alerting nor validity effects interacted with the flanker effect. These results suggest that the alerting cue primes the exogenous and endogenous systems for the upcoming cues. Once the complexity of the task increases with the addition of the flankers, the alerting effect attenuates. The alerting and the two orienting networks interact together but the executive attention network acts independently, in children aged 6 years. [ABSTRACT FROM AUTHOR]

• Manual and saccadic measures of attention yield different developmental profiles. • Orienting measured by saccade-to-target showed no change between ages 6 to 12. • Orienting measured by manual button press task showed age-related change. • Manual target detection tasks measure skills above and beyond endogenous attention. • Endogenous visual attention is mature by age 6. There is a long-standing assumption that covert measurement of orienting, the shifting of the "mind's eye" independent of a saccade to a location in space, is a more "pure" measure of underlying attention than overt measurement of orienting. Testing attention covertly often relies on target detection tasks, which depend on making a decision about when and where a target has appeared and what is the appropriate action, all of which are potential confounds in measuring attention in children. This study cross-sectionally examined developmental profiles at ages 6–12 years of endogenous visual orienting. We used two tasks: one that measured orienting with a traditional covert attention button press response and one that measured orienting with eye tracking to measure overt saccades. The results obtained from the two orienting tasks demonstrate that each task measures distinct underlying processes with clear developmental profiles. Orienting, when measured by overt saccades, may be mature by 6 years of age, whereas the more complex manual response selection skills required in manual reaction time covert attention tasks continue to develop through middle childhood. [ABSTRACT FROM AUTHOR]

Abstract Individuals with developmental dyslexia have been characterized by problems with attentional orienting. In the current study, we specifically focused on possible changes in endogenous visual orienting that may be reflected in the electroencephalogram. A variant of the Posner cuing paradigm was employed with valid or invalid central cues that preceded target stimuli that were presented in the left or right visual field. The target stimuli consisted of vertical or horizontal stripes with low (two thick lines) or high (six thin lines) spatial frequencies. We examined lateralized alpha power in the cue-target interval as recent studies revealed that a contra vs. ipsilateral reduction in alpha power relates to the orienting of attention. An initial orienting effect in the lower alpha band was more pronounced for dyslexic individuals than for controls, suggesting that they oriented at an earlier moment in time. However, in contrast with controls, at the end of the cue-target interval no clear contralateral reduction in the upper alpha band was observed for dyslexic individuals. Dyslexic individuals additionally displayed slower responses, especially for invalidly cued high spatial frequency targets in the left visual field. The current data support the view that dyslexic individuals orient well to the cued location but have a problem with sustaining their attention. Highlights • Dyslexic individuals and controls performed an endogenous orienting task. • Dyslexic individuals responded slower than controls. • Their responses were partly in line with the mini-neglect hypothesis. • An early orienting effect in the α 1 band was more pronounced for dyslexic individuals. • A late orienting effect in the α 2 band was more pronounced for controls. [ABSTRACT FROM AUTHOR]

Current theories of attention differentiate exogenous from endogenous orienting of visuospatial attention. While both forms of attention orienting engage different functional systems, endogenous and exogenous attention are thought to share resources, as shown by empirical evidence of their functional interactions. The present study aims to uncover the neurobiological basis of how salient events that drive exogenous attention disrupts endogenous attention processes. We hypothesize that interference from exogenous attention over endogenous attention involves alpha-band activity, a neural marker of visuospatial attention. To test this hypothesis, we contrast the effects of endogenous attention across two experimental tasks while we recorded electroencephalography (n = 32, both sexes): a single cueing task where endogenous attention is engaged in isolation, and a double cueing task where endogenous attention is concurrently engaged with exogenous attention. Our results confirm that the concurrent engagement of exogenous attention interferes with endogenous attention processes. We also found that changes in alpha-band activity mediate the relationship between endogenous attention and its effect on task performance, and that the interference of exogenous attention on endogenous attention occurs via the moderation of this indirect effect. Altogether, our results substantiate a model of attention, whereby endogenous and exogenous attentional processes involve the same neurophysiological resources., Significance Statement: Scientists differentiate top-down from bottom-up visuospatial attention processes. While bottom-up attention is rapidly engaged by emerging demands from the environment, top-down attention in contrast reflects slow voluntary shifts of spatial attention. Several lines of research substantiate the idea that top-down and bottom-up attentional processes involve distinct functional systems. An increasing number of studies, however, argue that both attention systems share brain processing resources. The current study examines how salient visual events that engage bottom-up processes interfere with top-down attentional processes. Using neurophysiological recordings and multivariate pattern classification techniques, the authors show that these patterns of interference occur within the alpha-band of neural activity (8-12 Hz), which implies that bottom-up and top-down attention processes share this narrow-band frequency brain resource. The results further demonstrate that patterns of alpha-band activity explains, in part, the interference between top-down and bottom-up attention at the behavioral level., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The literature has long emphasized the neocortex's role in volitional processes. In this work, we examined endogenous orienting in an evolutionarily older species, the archer fish, which lacks neocortexlike cells. We used Posner's classic endogenous cuing task, in which a centrally presented, spatially informative cue is followed by a target. The fish responded to the target by shooting a stream of water at it. Interestingly, the fish demonstrated a human-like "volitional" facilitation effect: their reaction times to targets that appeared on the side indicated by the precue were faster than their reaction times to targets on the opposite side. The fish also exhibited inhibition of return, an aftermath of orienting that commonly emerges only in reflexive orienting tasks in human participants. We believe that this pattern demonstrates the acquisition of an arbitrary connection between spatial orienting and a nonspatial feature of a centrally presented stimulus in nonprimate species. In the literature on human attention, orienting in response to such contingencies has been strongly associated with volitional control. We discuss the implications of these results for the evolution of orienting, and for the study of volitional processes in all species, including humans. [ABSTRACT FROM AUTHOR]

Titchener's (1908) law of prior entry states that 'the object of attention comes to consciousness more quickly than the objects which we are not attending to,' or otherwise, that attended stimuli are perceived earlier than unattended stimuli. Shore, Spence, and Klein ( Psychological Science, 12, 205-212. doi:, 2001) showed that endogenous visuospatial orienting does in fact elicit prior-entry effects, albeit to a smaller degree than does exogenous visuospatial orienting. In disagreement with this finding, Schneider and Bavelier ( Cognitive Psychology, 47, 333-366. doi:, 2003) found no effect of their instruction to attend. They concluded that nonattentional effects could masquerade as prior entry, which could account for findings such as those in Shore et al.'s endogenous condition. We investigated this empirical and theoretical discord by replicating the temporal-order judgment task used by Shore, Spence, and Klein, while manipulating and measuring endogenous orienting by way of an orthogonal color probe task. We showed evidence of prior entry as a consequence of endogenous orienting, supporting the conclusions of Shore, Spence, and Klein. [ABSTRACT FROM AUTHOR]

The requirement to orient attention in space and time usually occurs simultaneously. Previous reports were indecisive regarding possible interactions between temporal and spatial orienting. The present study examined whether temporal and spatial orienting can operate simultaneously and independently in the framework of a detection task. Participants completed three consecutive target detection tasks: in the first two tasks a central cue provided predictive information regarding either the temporal delay of the target or its spatial location. In a third task the temporal and spatial cues from the first two tasks were combined into a single cue. Temporal and spatial information provided by the combined cue could be valid or invalid for each type of information separately. Results from the combined temporal-spatial task revealed that at a short cue-to-target interval temporal validity effects were significant at the attended and unattended spatial locations and were not modulated by spatial validity conditions. Spatial validity effects were also significant and comparable between the valid and invalid temporal conditions. Moreover, temporal and spatial validity effects in the combined task were equivalent to those attained in the separate tasks. At a long cue-to-target delay, spatial validity effects were significant and were not modulated by temporal validity but there were no temporal validity effects. Overall, the results suggest that participants were able to extract temporal and spatial information provided by a single cue simultaneously and independently. We conclude that temporal and spatial endogenous orienting function orthogonally in a task that does not require demanding perceptual discrimination. [ABSTRACT FROM AUTHOR]

It was demonstrated that central arrows produce orienting of attention even when they are nonpredictive as to the target location. This finding was suggested to indicate reflexive orienting of attention by central arrows. However, it is not clear whether central arrows can produce an attentional effect without awareness. In two experiments, using a variation of the inattentional blindness task, we examine whether orienting of attention by a central arrow can be demonstrated without conscious perception of the arrow. We found that attention could be directed to the cued location even when the arrow was not consciously perceived. [ABSTRACT FROM AUTHOR]

Chen, X., Chen, Q., Gao, D. & Yue, Z. (2012). Interaction between endogenous and exogenous orienting in crossmodal attention. Scandinavian Journal of Psychology 53, 303-308. Using a cue-target paradigm, we investigated the interaction between endogenous and exogenous orienting in cross-modal attention. A peripheral (exogenous) cue was presented after a central (endogenous) cue with a variable time interval. The endogenous and exogenous cues were presented in one sensory modality (auditory in Experiment 1 and visual in Experiment 2) whereas the target was presented in another modality. Both experiments showed a significant endogenous cuing effect (longer reaction times in the invalid condition than in the valid condition). However, exogenous cuing produced a facilitatory effect in both experiments in response to the target when endogenous cuing was valid, but it elicited a facilitatory effect in Experiment 1 and an inhibitory effect in Experiment 2 when endogenous cuing was invalid. These findings indicate that endogenous and exogenous cuing can co-operate in orienting attention to the crossmodal target. Moreover, the interaction between endogenous and exogenous orienting of attention is modulated by the modality between the cue and the target. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Studies on brain computer interfaces (BCIs) have been mainly concerned with algorithm improvement for better signal classification. Fewer studies, however, have addressed to date the role of cognitive mechanisms underlying the elicitation of brain-signals in BCIs. We tested the effect of visuospatial attention orienting on a P300-guided BCI, by comparing the effectiveness of three visual interfaces, which elicited different modalities of visuospatial attention orienting (exogenous vs. endogenous). Methods: Twelve healthy participants performed 20 sessions, using the abovementioned P300-guided BCI interfaces to control a cursor. Brain waves were recorded on each trial and were subsequently classified on-line using an ad hoc algorithm. Each time the P300 was correctly classified, the cursor moved towards the target position. Results: The “endogenous” interface was associated with significantly higher performance than the other two interfaces during the testing sessions, but not in the follow-up sessions. Conclusions: Endogenous visuospatial attention orienting can be effectively implemented to increase the performance of P300-guided BCIs. Significance: The study of visuospatial attention underlying participants’ performance is essential for implementing efficient visual BCIs. [Copyright &y& Elsevier]

Abstract: The goal of the present study was to explore whether endogenous attention can be oriented to different perceptual categories and to examine how these expectations modulate visual stimulus processing. We designed a cueing paradigm that prepared participants, on a trial-by-trial basis, for the most likely stimulus category of the target, which could be either a face or a word. Participants were asked to discriminate the gender of the stimuli, regardless of their category. We measured participants’ brain activity by means of a high-density electroencephalographic recording system to investigate the neural correlates of orienting attention to faces and words. As expected, we observed a behavioural facilitation for valid compared to invalid trials. In addition, target expectations influenced stimulus processing at several points in time. Most importantly, attention modulated the lateralized N170 component in a category-specific fashion. These results show that, at least under certain circumstances, orienting endogenous attention to different categories can influence the perceptual stages of face and word visual processing. [ABSTRACT FROM AUTHOR]

We studied endogenous cuing during the attentional blink in order to examine its resistance to dual task interference. In two experiments, we found a reduced impact of endogenous cuing during the “blink” time of the attentional blink. In a third experiment endogenous cuing was intact when it was not influenced by demands imposed by an earlier target. Contrary to a recent report (Zhang et al. in Exp Brain Res, 185, 287–295, ), the results indicate that endogenous orienting guided by semantic cues is susceptible to the attentional blink. [ABSTRACT FROM AUTHOR]

In this study, we investigate how exogenous and endogenous orienting of spatial attention affect visuospatial working memory (VSWM). Specifically, we focused on two attentional effects and their consequences on storage in VSWM, when exogenous (Experiment 1) or endogenous (Experiment 2) orienting cues were used. The first effect, known as the meridian effect, is given by a decrement in behavioural performance when spatial cues and targets are presented in locations separated by vertical and/or horizontal meridians. The second effect, known as the distance effect, is given by a decrement in the orienting effects as a function of the spatial distance between cues and targets. Our results revealed a dissociation between exogenous and endogenous orienting mechanisms in terms of both meridian and distance effects. We found that meridian crossing affects performance only when endogenous cues were used. Specifically, VSWM performance with endogenous cueing depended more on the number of meridian crossings than on distance between cue and target. By contrast, a U-shaped distance dependency was observed using exogenous cues. Our findings therefore suggest that exogenous and endogenous orienting mechanisms lead to different forms of attentional bias for storage in VSWM. [ABSTRACT FROM AUTHOR]

The spatial relevance hypothesis (J. J. McDonald & L. M. Ward, 1999) proposes that covert auditory spatial orienting can only be beneficial to auditory processing when task stimuli are encoded spatially. We present a series of experiments that evaluate 2 key aspects of the hypothesis: (a) that "reflexive activation of location-sensitive neurons is not sufficient to produce attentional facilitation" and (b) that "any task constraint that makes space important for the listener will produce auditory spatial cue effects" (p. 1236). Experiment 1 showed significant reflexive-orienting benefits on a nonspatial task, refuting the first claim. However, Experiments 2 to 4 reveal that informative spatial cues can improve performance on a nonspatial task, consistent with the second claim. Auditory spatial-cue benefits found with nonspatial tasks appear smaller and less reliable than those found in visual spatial-orienting studies, possibly due to differences in the coding of spatial information in vision and audition. The final experiments consider the mechanisms by which auditory spatial orienting might facilitate auditory processing and provide tentative evidence that attention enhances processing at one ear rather than influencing neurons tuned to the attended location. [ABSTRACT FROM AUTHOR]

Background: Are persons with autism spectrum disorders (ASD) slower than typically developing individuals to read the meaning of a symbolic cue in a visual orienting paradigm? Methods: Participants with ASD ( n = 18) and performance mental age (PMA) matched typically developing children ( n = 16) completed two endogenous orienting conditions in which the cue exposure time and response preparation time were manipulated within a consistent series of cue-target stimulus onset asynchronies (SOAs). Results: Participants with ASD displayed facilitation effects at all SOAs, whereas typically developing children displayed facilitation effects only at shorter SOAs. The magnitude of the facilitation effect was greater for the group with ASD at 400ms SOA. Both groups showed similar effects of condition, with similar patterns of facilitation in both conditions. Conclusion: Persons with ASD were not slower to read the symbolic cue, as the effect was elicited by brief cues within longer SOAs before target onset. The participants with ASD were also less efficient in using the predictability of the cues to guide responding. The difficulties of participants with ASD on endogenous orienting occur at the response selection level, not the perceptual level. [ABSTRACT FROM AUTHOR]

The common view on the interplay between exogenous and endogenous orienting holds that abrupt onsets are not capable of attracting attention when they occur outside the current focus of attention. Does this also apply to sudden irrelevant auditory onsets and when irrelevant visual onsets occur far in the periphery? In addition, does focused attention also reduce the alerting effect of auditory onsets, or vice versa, do highly alerting stimuli distort the attentional state? Crossmodal and unimodal variants of the Posner paradigm were examined in two experiments with targets and irrelevant onsets occurring at 28.3 and 19.3° from fixation. Either centrally presented arrows indicated the forthcoming position of visual targets to be discriminated, or warning cues signaled the likely moment of target occurrence. The targets could be preceded by peripheral auditory or visual onsets that were to be ignored. Crossmodal and unimodal exogenous orienting effects of these irrelevant onsets were observed while participants focused at the relevant side. In addition, no evidence was found that the alerting effect of auditory onsets was dependent on focused attention. Our findings indicate that, at least under the current conditions, neither crossmodal nor unimodal orienting effects of peripheral events dissipate when attention is in a focused state. [ABSTRACT FROM AUTHOR]

Inhibition of return (IOR) is thought to reflect a bias against returning attention to previously attended locations. According to this view, IOR should occur only if attention is withdrawn from the target location prior to target appearance. In the present study, endogenous attention and exogenous cueing were manipulated orthogonally. IOR was observed both when a target appeared at an unexpected location, and when a target appeared at the expected location. A similar pattern of results was obtained in a reanalysis of data from a study with Neglect patients. These results suggest that IOR is independent of endogenous orienting. [ABSTRACT FROM AUTHOR]

After right posterior brain damage, patients may ignore events occurring on their left, a condition known as unilateral neglect. Although deficits at different levels of impairment may be at work in different patients, the frequency and severity of attentional problems in neglect patients have been repeatedly underlined. Recent advances in the knowledge of the mechanisms of spatial attention in normals may help characterizing these deficits. The present review focuses on studies exploring several aspect of attentional processing in unilateral neglect, with particular reference to the dichotomy between ‘exogenous’, or stimulus-related, and ‘endogenous’, or strategy-driven, orienting of attention. A large amount of neuropsychological evidence suggests that a basic mechanism leading to left neglect behavior is an impaired exogenous orienting toward left-sided targets. In contrast, endogenous processes seem to be relatively preserved, if slowed, in left unilateral neglect. Other component deficits, such as a general slowing of the operations of spatial attention, might contribute to neglect behavior. These results are presented and discussed, and their implications for hemispheric specialization in attentional orienting and for the mechanisms of visual consciousness are explored. [Copyright &y& Elsevier]

Left unilateral neglect is a neurological condition characterized by an impairment in orienting and responding to events occurring on the left side. To gain insight into the brain mechanisms of space processing and to provide theoretical foundations for patient rehabilitation, it is important to explore the attentional bias shown by neglect patients in the light of existing models of normal attentional orienting. Three experiments tested the hypothesis that attentional bias in neglect involves primarily exogenous, or stimulus-based, orienting of attention, with relatively preserved endogenous, or voluntary, orienting. Six patients with right hemisphere damage and left unilateral neglect and 18 age-matched participants without brain damage performed a cued reaction time (RT) task to targets which could appear in one of two lateral boxes. Cues consisted of a brief brightening of the contour of one of the boxes. The target followed the cue at 150, 550, or 1000 ms stimulus-onset asynchrony (SOA). In experiment 1, the cues were not informative about the future location of the target, and thus elicited a purely exogenous orienting of attention. Controls showed slowed RTs to the cued locations at SOAs > 150 ms, consistent with the notion of inhibition of return (IOR). Neglect patients had no evidence of IOR for right targets; they showed a disproportionate cost for left targets preceded by right (invalid) cues; this cost was maximal at the shortest SOA, consistent with the idea of a biased exogenous orienting in neglect. In experiment 2, 80% of the cues were valid (i.e., they correctly predicted the location of the impending target), thus inducing an initially exogenous, and later endogenous, attentional shift toward the cued box. Neglect patients showed again a cost for left invalidly cued targets, which this time persisted at SOAs > 150 ms, as if patients' attention had been cued to the right side not only exogenously, but also endogenously, thus rendering more difficult an endogenous reorienting toward the left. In experiment 3, only 20% of the cues were valid, so that the best response strategy was to endogenously orient attention toward the box opposite to the cued one. Controls were able to take advantage of invalid cues to rapidly respond to targets. In this condition, neglect patients were able to nullify their spatial bias; they achieved their fastest RTs to left targets, which were in the range of their RTs to right targets. However, for neglect patients fast responses to left targets occurred only at 1000 ms SOA, while controls were able to redirect their attention to the uncued box already at 550 ms SOA. Altogether, these results suggest that endogenous orienting is relatively spared, if slowed, in unilateral neglect. [ABSTRACT FROM AUTHOR]