ORCID Profile
0000-0002-5903-4104
Current Organisation
University of Tasmania Launceston Campus
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Publisher: Elsevier BV
Date: 04-2015
DOI: 10.1016/J.JNEUMETH.2015.02.008
Abstract: Event-related potentials (ERPs) may provide a non-invasive index of brain function for a range of clinical applications. However, as a lab-based technique, ERPs are limited by technical challenges that prevent full integration into clinical settings. To translate ERP capabilities from the lab to clinical applications, we have developed methods like the Halifax Consciousness Scanner (HCS). HCS is essentially a rapid, automated ERP evaluation of brain functional status. The present study describes the ERP components evoked from auditory tones and speech stimuli. ERP results were obtained using a 5-min test in 100 healthy in iduals. The HCS sequence was designed to evoke the N100, the mismatch negativity (MMN), P300, the early negative enhancement (ENE), and the N400. These components reflected sensation, perception, attention, memory, and language perception, respectively. Component detection was examined at group and in idual levels, and evaluated across both statistical and classification approaches. All ERP components were robustly detected at the group level. At the in idual level, nonparametric statistical analyses showed reduced accuracy relative to support vector (SVM) machine classification, particularly for speech-based ERPs. Optimized SVM results were MMN: 95.6% P300: 99.0% ENE: 91.8% and N400: 92.3%. A spectrum of in idual-level ERPs can be obtained in a very short time. Machine learning classification improved detection accuracy across a large healthy control s le. Translating ERPs into clinical applications is increasingly possible at the in idual level.
Publisher: Springer Science and Business Media LLC
Date: 25-11-2015
Publisher: MDPI AG
Date: 22-08-2019
Abstract: Inhibition of return is characterized by delayed responses to previously attended locations when the cue-target onset asynchrony (CTOA) is long enough. However, when cues are predictive of a target’s location, faster reaction times to cued as compared to uncued targets are normally observed. In this series of experiments investigating saccadic reaction times, we manipulated the cue predictability to 25% (counterpredictive), 50% (nonpredictive), and 75% (predictive) to investigate the interaction between predictive endogenous facilitatory (FCEs) and inhibitory cueing effects (ICEs). Overall, larger ICEs were seen in the counterpredictive condition than in the nonpredictive condition, and no ICE was found in the predictive condition. Based on the hypothesized additivity of FCEs and ICEs, we reasoned that the null ICEs observed in the predictive condition are the result of two opposing mechanisms balancing each other out, and the large ICEs observed with counterpredictive cueing can be attributed to the combination of endogenous facilitation at uncued locations with inhibition at cued locations. Our findings suggest that the endogenous activity contributed by cue predictability can reduce the overall inhibition observed when the mechanisms occur at the same location, or enhance behavioral inhibition when the mechanisms occur at opposite locations.
Publisher: Springer Science and Business Media LLC
Date: 11-10-2012
DOI: 10.1007/S00221-012-3279-1
Abstract: Automatic attentional capture by a salient distractor can be prevented by spatial attentional control settings (ACSs) (e.g., Yantis and Jonides in J Exp Psychol Hum Percept Perform 16:121-134, 1990). Earlier, converging evidence for a spatial ACS (Eason et al. 1969) was found in event-related potentials (ERPs). In these studies, the ACS was defined by a single target-relevant location. In an extension, Ishigami et al. (Vis Cogn 17:431-456, 2009) demonstrated a successful ACS in performance that was based on multiple (two) target-relevant locations. The purpose of the current study is to seek converging evidence from ERPs for a spatial ACS defined by multiple (two) target-relevant locations, using the methods in Ishigami et al. (Vis Cogn 17:431-456, 2009). Any one of four figure-8s brightened uninformatively (cue) before presentation of a digit target calling for a speeded identification (2 or 5). A spatial ACS was encouraged because in different blocks, the digit targets appeared only on the horizontal or vertical axis. Performance was more impaired following the invalid-attended cues than following invalid-unattended cues, consistent with Ishigami et al. (Vis Cogn 17:431-456, 2009) and verifying a successful spatial ACS. The direction of attention significantly affected the visual evoked potentials (VEPs) elicited by otherwise identical cues: the litudes of early VEPs were greater when the location the cue was presented in was target-relevant than when the location was target-irrelevant. These results re-affirm that attentional capture by irrelevant salient stimuli can be modulated by spatial ACSs defined by multiple target locations in performance and provide converging evidence from ERPs for the previously established behavioral findings.
Publisher: Springer Science and Business Media LLC
Date: 05-10-2012
DOI: 10.1007/S00221-012-3274-6
Abstract: It has recently been demonstrated that there are independent sensory and motor mechanisms underlying inhibition of return (IOR) when measured with oculomotor responses (Wang et al. in Exp Brain Res 218:441-453, 2012). However, these results are seemingly in conflict with previous empirical results which led to the proposal that there are two mutually exclusive flavors of IOR (Taylor and Klein in J Exp Psychol Hum Percept Perform 26:1639-1656, 2000). The observed differences in empirical results across these studies and the theoretical frameworks that were proposed based on the results are likely due to differences in the experimental designs. The current experiments establish that the existence of additive sensory and motor contributions to IOR do not depend on target type, repeated spatiotopic stimulation, attentional control settings, or a temporal gap between fixation offset and cue onset, when measured with saccadic responses. Furthermore, our experiments show that the motor mechanism proposed by Wang et al. in Exp Brain Res 218:441-453, (2012) is likely restricted to the oculomotor system, since the additivity effect does not carry over into the manual response modality.
Publisher: Springer Science and Business Media LLC
Date: 22-02-2017
DOI: 10.3758/S13414-017-1295-8
Abstract: There are thought to be two forms of inhibition of return (IOR) depending on whether the oculomotor system is activated or suppressed. When saccades are allowed, output-based IOR is generated, whereas input-based IOR arises when saccades are prohibited. In a series of 4 experiments, we mixed or blocked compatible and incompatible trials with saccadic or manual responses to investigate whether cueing effects would follow the same pattern as those observed with more traditional peripheral onsets and central arrows. In all experiments, an uninformative cue was displayed, followed by a cue-back stimulus that was either red or green, indicating whether a compatible or incompatible response was required. The results showed that IOR was indeed observed for compatible responses in all tasks, whereas IOR was eliminated for incompatible trials-but only with saccadic responses. These findings indicate that the dissociation between input- and output-based forms of IOR depends on more than just oculomotor activation, providing further support for the existence of an inhibitory cueing effect that is distinct to the manual response modality.
Publisher: Global Science & technology Forum ( GSTF )
Date: 22-02-2016
Publisher: Informa UK Limited
Date: 08-2012
Publisher: University of Bern
Date: 24-05-2011
DOI: 10.16910/JEMR.4.2.1
Abstract: When viewing a scene or searching for a target, an observer usually makes a series of saccades that quickly shift the orientation of the eyes. The present study explored how one saccade affects subsequent saccades within a dynamic neural field model of the superior colliculus (SC). The SC contains an oculocentric motor map that encodes the vector of saccades and remaps to the new fixation location after each saccade. Our simulations demonstrated that the observation that saccades which reverse their vectors are slower to initiate than those which repeat vectors can be explained by the afore-mentioned remapping process and the internal dynamics of the SC. How this finding connects to the study of inhibition of return is discussed and suggestions for future studies are presented.
Publisher: Springer Science and Business Media LLC
Date: 26-05-2012
DOI: 10.3758/S13414-012-0312-1
Abstract: When, in relation to the execution of an eye movement, does the recoding of visual information from retinotopic to spatiotopic coordinates happen? Two laboratories seeking to answer this question using oculomotor inhibition of return (IOR) have generated different answers: Mathôt and Theeuwes (Psychological Science 21:1793-1798, 2010) found evidence for the initial coding of IOR to be retinotopic, while Pertzov, Zohary, and Avidan (Journal of Neuroscience 30:8882-8887, 2010) found evidence for spatiotopic IOR at even shorter postsaccadic intervals than were tested by Mathôt and Theeuwes (Psychological Science 21:1793-1798, 2010). To resolve this discrepancy, we conducted two experiments that combined the methods of the previous two studies while testing as early as possible. We found early spatiotopic IOR in both experiments, suggesting that visual events, including prior fixations, are typically coded into an abstract, allocentric representation of space either before or during eye movements. This type of coding enables IOR to encourage orienting toward novelty and, consequently, to perform the role of a foraging facilitator.
Publisher: IEEE
Date: 2005
Publisher: Wiley
Date: 27-06-2014
DOI: 10.1111/PSYP.12245
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.BRAINRES.2015.09.028
Abstract: The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial-frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with previous work, we found that the higher level of cognitive load reduced the litude of the feedback-related negativity, a component of the human event-related brain potential associated with reward evaluation within the medial-frontal cortex. Importantly, our results provide further support that increased cognitive load reduces the functional efficacy of a neural system associated with reward processing.
Publisher: Mary Ann Liebert Inc
Date: 02-2022
Abstract: The recent recognition of Gaming Disorder (GD) as a mental health issue has provided a unique opportunity for researchers to advance our current understanding of the intricate relationships between GD and specific health-related factors and well-being. This study sought to investigate the role of key physical and psychological health and well-being factors in GD. To achieve this, three goals were explored. First, we tested whether GD can be predicted by health and well-being factors such as depression, anxiety, loneliness, attention problems, physical health problems (PHP), and psychological well-being (PWB). Second, we assessed the role of distress tolerance (DT) as a moderator in the relationship between PWB and GD. Third, we examined whether PWB would mediate the relationship between PHP and GD. A s le of 474 participants (Mean
Publisher: Springer Science and Business Media LLC
Date: 24-11-2020
Publisher: Elsevier BV
Date: 03-2014
DOI: 10.1016/J.VISRES.2013.11.008
Abstract: Inhibition of return (IOR) most often describes the finding of increased response times to cued as compared to uncued targets in the standard covert orienting paradigm. A perennial question in the IOR literature centers on whether the effect of IOR is on motoric/decision-making processes (output-based IOR), attentional erceptual processes (input-based IOR), or both. Recent data converge on the idea that IOR is an output-based effect when eye movements are required or permitted whereas IOR is an input-based effect when eye movements are monitored and actively discouraged. The notion that the effects of IOR may be fundamentally different depending on the activation state of the oculomotor system has been challenged by several studies demonstrating that IOR exists as an output-, or output- plus input-based effect in simple keypress tasks not requiring oculomotor responses. Problematically, experiments in which keypress responses are required to visual events rarely use eye movement monitoring let alone the active discouragement of eye movement errors. Here, we return to an experimental method implemented by Ivanoff and Klein (2001) whose results demonstrated that IOR affected output-based processes when, ostensibly, only keypress responses occurred. Unlike Ivanoff and Klein, however, we assiduously monitor and discourage eye movements. We demonstrate that actively discouraging eye movements in keypress tasks changes the form of IOR from output- to input-based and, as such, we strongly encourage superior experimental control over or consideration of the contribution of eye movement activity in simple keypress tasks exploring IOR.
Publisher: Springer Science and Business Media LLC
Date: 08-03-2016
DOI: 10.3758/S13414-016-1079-6
Abstract: With two cueing tasks, in the present study we examined output-based inhibitory cueing effects (ICEs) with manual responses to arrow targets following manual or saccadic responses to arrow cues. In all experiments, ICEs were observed when manual localization responses were required to both the cues and targets, but only when the cue-target onset asynchrony (CTOA) was 2,000 ms or longer. In contrast, when saccadic responses were made in response to the cues, ICEs were only observed with CTOAs of 2,000 ms or less-and only when an auditory cue-back signal was used. The present study also showed that the magnitude of ICEs following saccadic responses to arrow cues decreased with time, much like traditional inhibition-of-return effects. The magnitude of ICEs following manual responses to arrow cues, however, appeared later in time and had no sign of decreasing even 3 s after cue onset. These findings suggest that ICEs linked to skeletomotor activation do exist and that the ICEs evoked by oculomotor activation can carry over to the skeletomotor system.
Publisher: Frontiers Media SA
Date: 16-12-2020
DOI: 10.3389/FPSYG.2020.617140
Abstract: Given recent advances in technology, connectivity, and the popularity of social media platforms, recent literature has devoted great attention to problematic Facebook use. However, exploring the potential predictors of problematic social media use beyond Facebook use has become paramount given the increasing popularity of multiple alternative platforms. In this study, a s le of 584 social media users ( M age = 32.28 years 67.81% female) was recruited to complete an online survey assessing sociodemographic characteristics, patterns, and preferences of social media use, problematic social media use (PSMU), social media use motives, psychological well-being, self-esteem, and positive and negative affect. Results indicated that 6.68% ( n = 39) of all respondents could be potentially classed as problematic users. Moreover, further analysis indicated that intrapersonal motive (β = 0.38), negative affect (β = 0.22), daily social media use (β = 0.18), surveillance motive (β = 0.12), and positive affect (β = −0.09) each predicted PSMU. These variables accounted for about 37% of the total variance in PSMU, with intrapersonal motive driving the greatest predictive contribution, over and above the effects of patterns of social media use and sociodemographic variables. These findings contribute to the increasing literature on PSMU. The results of this study are discussed in light of the existing literature on PSMU.
Publisher: GSTF
Date: 24-02-2014
Publisher: Elsevier BV
Date: 02-2018
DOI: 10.1016/J.ACTPSY.2017.12.011
Abstract: Studies of endogenous and exogenous attentional orienting in spatial cueing paradigms have been used to investigate inhibition of return, a behavioral phenomenon characterized by delayed reaction time in response to recently attended locations. When eye movements are suppressed, attention is covertly oriented to central or peripheral stimuli. Overt orienting, on the other hand, requires explicit eye movements to the stimuli. The present study examined the time course of slowed reaction times to previously attended locations when distractors are introduced into overt and covert orienting tasks. In a series of experiments, manual responses were required to targets following central and peripheral cues at three different cue-target intervals, with and without activated oculomotor systems. The results demonstrate that, when eye movements are suppressed, behavioral inhibition is reduced or delayed in magnitude by the presence of a distractor relative to conditions without distractors. However, the time course of behavioral inhibition when eye movements are required remains similar with or without distractors.
Publisher: Informa UK Limited
Date: 17-12-2021
Publisher: American Psychological Association (APA)
Date: 2014
DOI: 10.1037/A0036859
Abstract: We explored the nature and time course of effects generated by spatially uninformative peripheral cues by measuring these effects with localization responses to peripheral onsets or central arrow targets. In Experiment 1, participants made saccadic eye movements to equiprobable peripheral and central targets. At short cue-target onset asynchronies (CTOAs), responses to cued peripheral stimuli suffered from slowed responding attributable to sensory adaptation while responses to central targets were transiently facilitated, presumably due to cue-elicited oculomotor activation. At the longest CTOA, saccadic responses to central and peripheral targets were indistinguishably delayed, suggesting a common, output/decision effect (inhibition of return IOR). In Experiment 2, we tested the hypothesis that the generation of this output effect is dependent on the activation state of the oculomotor system by forbidding eye movements and requiring keypress responses to frequent peripheral targets, while probing oculomotor behavior with saccades to infrequent central arrow targets. As predicted, saccades to central arrow targets showed neither the early facilitation nor later inhibitory effects that were robust in Experiment 1. At the long CTOA, manual responses to cued peripheral targets showed the typical delayed responses usually attributed to IOR. We recommend that this late "inhibitory" cueing effect (ICE) be distinguished from IOR because it lacks the cause (oculomotor activation) and effect (response bias) attributed to IOR when it was named by Posner, Rafal, Choate, and Vaughan (1985).
Publisher: Elsevier BV
Date: 08-2012
DOI: 10.1016/J.NEULET.2012.07.003
Abstract: Inhibition of return (IOR) is thought to reflect a mechanism that biases orienting which, under some circumstances, reduces perceptual processing at previously processed locations. Studies using event-related potentials (ERPs) have generally revealed that IOR is accompanied by an litude reduction of early sensory ERP components (e.g., P1). While behavioral studies suggest that IOR may be represented in both spatiotopic and retinotopic coordinates, all previous ERP studies have used the prototypical spatial cueing paradigm and have thus confounded retinotopic and spatiotopic reference frames. Because of this confound it is unknown whether the P1 reduction that has been associated with IOR will be observed in retinotopic or spatiotopic coordinates when these are dissociated. The current experiment investigated whether the P1 component would be modulated by IOR when the retinotopic and spatiotopic reference frames were dissociated by an eye movement between cue and target onset. Strong spatiotopic IOR was found to be accompanied by a negative difference (Nd) in the 200-300 ms time window, while a P1 reduction was absent, suggesting that P1 reductions do not provide an accurate reflection of IOR.
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.BANDC.2014.01.013
Abstract: Previous research has demonstrated that people are faster at making a manual response with the hand that is aligned with the handle of a manipulable object compared to its functional end. According to theories of embodied cognition (ETC), the presentation of a manipulable object automatically elicits sensorimotor simulations of the respective hand and these simulations facilitate the response. However, an alternative interpretation of these data is that handles preferentially attract visual attention, since attended stimuli and locations typically elicit faster responses. We investigated attentional biases elicited by manipulable and non-manipulable objects using event-related-potentials (ERPs). On each trial, a picture of a manipulable object was followed by a target dot that participants had to make a button-press to. The dot was located at either the handle or functional end of the object. Consistent with previous attentional cuing paradigms, we showed that the P1 ERP component was greater in response to targets cued by handles than by functional ends. These results suggest that object handles automatically bias covert attentional processes. These attentional biases may account for earlier behavioural findings, without any recourse to ETC.
Publisher: Springer Science and Business Media LLC
Date: 18-10-2013
DOI: 10.3758/S13414-012-0381-1
Abstract: Taylor and Klein (Journal of Experimental Psychology: Human Perception and Performance 26:1639-1656, 2000) discovered two mutually exclusive "flavors" of inhibition of return (IOR): When the oculomotor system is "actively suppressed," IOR affects input processes (the perception/attention flavor), whereas when the oculomotor system is "engaged," IOR affects output processes (the motor flavor). Studies of brain activity with ignored cues have typically reported that IOR reduces an early sensory event-related potential (ERP) component (i.e., the P1 component) of the brain's response to the target. Since eye movements were discouraged in these experiments, the P1 reduction might be a reflection of the perception/attention flavor of IOR. If, instead of ignoring the cue, participants made a prosaccade to the cue (and then returned to fixation) before responding to the target, the motor flavor of IOR should then be generated. We compared these two conditions while monitoring eye position and recording ERPs to the targets. If the P1 modulation is related to the perceptual/attentional flavor of IOR, we hypothesized that it might be absent when the motoric flavor of IOR was generated by a prosaccade to the cue. Our results demonstrated that target-related P1 reductions and behavioral IOR were similar, and significant, in both conditions. However, P1 modulations were significantly correlated with behavioral IOR only when the oculomotor system was actively suppressed, suggesting that P1 modulations may only affect behaviorally exhibited IOR when the attentional erceptual flavor of IOR is recruited.
Publisher: Springer Science and Business Media LLC
Date: 22-02-2012
DOI: 10.1007/S00221-012-3033-8
Abstract: We propose two explicit mechanisms contributing to oculomotor inhibition of return (IOR): sensory and motor. Sensory mechanism: repeated visual stimulation results in a reduction in visual input to the superior colliculus (SC) consequently, saccades to targets that appear at previously stimulated retinotopic locations will have longer latencies than those that appear at unstimulated locations. Motor mechanism: the execution of a saccade results in asymmetric activation in the SC as a result, saccades that reverse vectors will have longer latencies than those that repeat vectors. In the IOR literature, these two mechanisms correspond to IOR effects observed following covert exogenous orienting and overt endogenous orienting, respectively. We predict that these two independent mechanisms will have additive effects, a prediction that is confirmed in a behavioral experiment. We then discuss how our theory and findings relate to the oculomotor IOR literature.
Publisher: Springer Science and Business Media LLC
Date: 30-01-2013
DOI: 10.3758/S13423-013-0376-5
Abstract: When the interval between a spatially uninformative arrow and a visual target is short (<500 ms), response times (RTs) are fastest when the arrow points to the target. When this interval exceeds 500 ms, there is a near-universal absence of an effect of the arrow on RTs. Contrary to this expected pattern of results, Taylor and Klein (J Exp Psychol Hum Percept Perform 26:1639-1656, 2000) observed that RTs were slowest when a to-be-localized visual target occurred in the direction of a fixated arrow presented 1 s earlier (i.e., an "inhibitory" Cueing effect ICE). Here we examined which factor(s) may have allowed the arrow to generate an ICE. Our experiments indicated that the ICE was a side effect of subthreshold response activation attributable to a task-induced association between the arrow and a keypress response. Because the cause of this ICE was more closely related to subthreshold keypress activation than to oculomotor activation, we considered that the effect might be more similar to the negative compatibility effect (NCE) than to inhibition of return (IOR). This similarity raises the possibility that classical IOR, when caused by a spatially uninformative peripheral onset event and measured by a keypress response to a subsequent onset, might represent, in part, another instance of an NCE. Serendipitously, we discovered that context (i.e., whether an uninformative peripheral onset could occur at the time of an uninformative central arrow) ultimately determined whether the "inhibitory" aftermath of automatic response activation would affect output or input pathways.
Publisher: Springer Science and Business Media LLC
Date: 03-08-2022
Publisher: Springer International Publishing
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 08-05-2009
Publisher: Springer Science and Business Media LLC
Date: 08-03-2018
DOI: 10.1007/S00221-018-5225-3
Abstract: Inhibition of return (IOR) refers to an increase in reaction times to targets that appeared at a previously cued location relative to an uncued location, often investigated using a spatial cueing paradigm. Despite numerous studies that have examined many aspects of IOR, the neurophysiological mechanisms underlying IOR are still in dispute. The objective of the current research is to investigate the plausible mechanisms by manipulating the cue and target types between central and peripheral stimuli in a traditional cue-target paradigm with saccadic responses to targets. In peripheral-cueing conditions, we observed inhibitory cueing effects across all cue-target onset asynchronies (CTOAs) with peripheral targets, but IOR was smaller and arose later with central targets. No inhibition was observed in central-cueing conditions at any CTOAs. Empirical data were simulated using a two-dimensional dynamic neural field model. Our results and simulations support previous work demonstrating that, at short CTOAs, behavioral inhibition is only observed with repeated stimulation-an effect of sensory adaptation. With longer CTOAs, IOR is observed regardless of target type when peripheral cueing is used. Our findings suggest that behaviorally exhibited inhibitory cueing effects can be attributed to multiple mechanisms, including both attenuation of visual stimulation and local inhibition in the superior colliculus.
Publisher: Elsevier BV
Date: 06-2022
Publisher: MDPI AG
Date: 29-10-2019
Abstract: An inhibitory aftermath of orienting, inhibition of return (IOR), has intrigued scholars since its discovery about 40 years ago. Since then, the phenomenon has been subjected to a wide range of neuroscientific methods and the results of these are reviewed in this paper. These include direct manipulations of brain structures (which occur naturally in brain damage and disease or experimentally as in TMS and lesion studies) and measurements of brain activity (in humans using EEG and fMRI and in animals using single unit recording). A variety of less direct methods (e.g., computational modeling, developmental studies, etc.) have also been used. The findings from this wide range of methods support the critical role of subcortical and cortical oculomotor pathways in the generation and nature of IOR.
Publisher: Global Science & technology Forum ( GSTF )
Date: 22-02-2016
Publisher: Springer Science and Business Media LLC
Date: 02-03-2011
DOI: 10.1007/S10548-011-0172-3
Abstract: Facilitation and inhibition of return (IOR) are, respectively, faster and slower responses to a peripherally cued target. In a spatially uninformative peripheral cueing task, facilitation is normally observed when the interval between the cue and target stimulus, the stimulus onset asynchrony (SOA), is shorter than 250 ms, while IOR is normally observed when an SOA greater than 250 ms is used. Since Posner and Cohen's (Attention and performance X, 1984) seminal study, IOR has become an actively investigated component of orienting. In this study, using ERPs and the source localization algorithm, LORETA, we seek to examine the brain mechanisms involved in IOR by localizing the different stages of processing after the appearance of a cue that captures attention exogenously. Unlike previous ERP investigations of IOR, this study analyzes the neural activity (via EEG) produced in response to the cue, prior to the appearance of the target. Neural activations were approximately ided into three stages. In the early stage (110-240 ms), involved activations are in the prefrontal cortex, the bilateral intraparietal cortex, and the contralateral occipito-temporal cortex. In the middle stage (240-350 ms), activations are primarily found in the frontal cortex and the parietal cortex. In the late stage (350-650 ms), the main activations are in the occipito-parietal cortex, but unlike in the early stage, the activation areas have shifted to the hemisphere ipsilateral to the cued location. These findings indicate that IOR is related to both attentional and motor response processes and suggest that the time course of initial facilitation and IOR is concurrent and mediated by two neural networks. Building upon our results, electrophysiological, electroencephalographic, and behavioral results in the literature and extending previous spatial theories of IOR, we propose here a spatio-temporal theory of IOR based upon post-cue dynamics.
No related grants have been discovered for Jason Satel.