Long-term inhibition of return of attention

Levels of neuroticism can predict attentional performance during cross-modal nonspatial repetition inhibition

Inhibition of return (IOR) refers to the slower response to targets presented at previously attended locations, and such repetition-induced inhibition has been found to be differentially associated with personality traits. Although it has been well documented how personality traits affect spatial IOR, a mechanism associated with the attentional orienting network, there is not yet a consensus as to the relationship between personality traits and nonspatial repetition inhibition, a mechanism associated with the attentional executive network. The present study herein examined how the Big Five personality traits relate to cross-modal nonspatial repetition inhibition. Participants completed the NEO-PI-R and performed a cross-modal nonspatial repetition inhibition task built on the prime-neutral cue-target paradigm, in which the relationships of the identities and modalities between the prime and the target were manipulated. The results showed a significant nonspatial inhibitory effect and the effect was larger under the visual-auditory condition than under the auditory-visual condition. More importantly, neuroticism was associated with decreased cross-modal nonspatial inhibitory effect, presumably due to impaired attentional control. However, such a result was only found in the visual-auditory condition. We propose that retrieving previous prime representations under the visual-auditory condition requires a large consumption of cognitive resources, making inhibitory control more difficult for individuals with high neuroticism. These findings provide new insight into the influence of personality traits on attentional performance requiring nonspatial inhibitory control and enrich the relationship between neuroticism and repetition-induced inhibition.

Location-response binding and inhibition of return in a detection task

In the present study, we investigated the binding of location and response in a detection task of the target-target paradigm of inhibition of return (IOR). Results showed a cost of responding to a target at the repeated location (IOR) when the response was not repeated and an effect of facilitation of return (FOR) when the response was repeated. These findings suggest that when responding to a target, its location and the response to it are integrated together. In addition, an analysis of the Vincentized cumulative response time (RT) distribution further showed that memory retrieval of event representations requires time to operate. These findings were discussed according to the theoretical framework of event files.

Motor-response execution versus inhibition alters social-emotional evaluations of specific individuals

Social-emotional evaluations of unfamiliar people are negatively impacted by ignoring or withholding motor-responses from images that depict them; an effect attributed to the propensity of inhibition to affectively devalue associated stimuli. Prior findings suggest that the social-emotional consequences of inhibition may operate on category-level representations that impact all members of a corresponding group. Here we assess whether such social-emotional consequences of motor-response action versus inaction also operate on item-level representations of specific individuals. Participants memorized individual identities of a group of fellow students before completing a Go/No-go response-inhibition task designed to associate item-level representations of each previously-memorized person with action (Go trials) or inaction (No-go trials). Social identities associated with action were consistently rated as more trustworthy in subsequent evaluations than those associated with inaction. This suggests that the social-emotional consequences of motor-response execution versus inhibition can operate on item-level stimulus representations in memory.

Crossmodal Nonspatial Repetition Inhibition Due to Modality Shift

Previous studies have found that processing of a second stimulus is slower when the modality of the first stimulus differs, which is termed the modality shift effect. Moreover, people tend to respond more slowly to the second stimulus when the two stimuli are similar in the semantic dimension, which is termed the nonspatial repetition inhibition effect. This study aimed to explore the modality shift effect on nonspatial repetition inhibition and whether such modulation was influenced by different temporal intervals. A cue-target paradigm was adopted in which modality priming and identity priming were manipulated at three interstimuli intervals. The results showed that the response times under the modality shift condition were slower than those under the modality repeat condition. In trials with modality shift, responses to congruent cues and targets were slower than to incongruent cue-target combinations, indicating crossmodal nonspatial repetition inhibition. The crossmodal nonspatial repetition inhibition effect decreased with increasing interstimuli interval. These results provide evidence that the additional intervening event proposed in previous studies is not necessary for the occurrence of crossmodal nonspatial repetition inhibition.

Contextual Similarity Between Successive Targets Modulates Inhibition of Return in the Target-Target Paradigm

Inhibition of return (IOR) refers to slower responses to a target presented at a previously cued vs. uncued location. The present study investigated the role of memory retrieval in IOR by manipulating the contextual similarity between two successive targets in the target-target IOR paradigm. Successive targets were presented in either the same color (same-context condition) or different colors (different-context condition). Results of two experiments showed that IOR was greater in the same-context than the different-context condition. In addition, Experiment 2 showed that this context effect occurs with long response times (RTs), suggesting that memory retrieval, which requires time to manifest, plays an important role in IOR.

Cross-modal nonspatial repetition inhibition: An ERP study

Previous studies have demonstrated that nonspatial repetition inhibition can occur across modalities. However, the underlying mechanism of such cross-modal nonspatial repetition inhibition is unknown. The present experiment adopted a cross-modal prime-neutral cue-target paradigm in which in consecutive trials the prime and the target were matched or mismatched, not only in identity but also in modality. Meanwhile, event-related potentials (ERPs) to visual and auditory targets were recorded. The present study aimed to answer two questions: which ERP components reflect nonspatial repetition inhibition across modalities, and is the ERP component modality specific or supramodal? The results showed that for visual targets, robust nonspatial repetition inhibition occurred similarly for both unimodal (visual-visual) and cross-modal (audio-visual) target pairings, as indexed by an N400 repetition-induced increment in the typical N400 window but null effects during the N2 epoch. For auditory targets, similar modulation of cross-modal nonspatial repetition inhibition on the auditory-evoked N400 repetition-induced increment was observed. These results suggest that the N400 repetition-induced increment occurs during the N400 epoch that underlies cross-modal nonspatial repetition inhibition and that this N400 component is a supramodal component.

The role of transients in action observation

A large number of studies have now described the various ways in which the observation of another person's dynamic movement can influence the speed with which the observer is able to prepare a motor action themselves. The typical results are most often explained with reference to theories that link perception and action. Such theories argue that the cognitive structures associated with each share common representations. Consequently, action preparation and action observation are often said to be functionally equivalent. However, the dominance of these theories in explaining action observation effects has masked the potential contribution from processes associated with the detection of low-level "transients" resulting from observing a body movement, such as motion and sound. In the present review, we describe work undertaken in one particular action observation phenomenon ("social inhibition of return") and show that the transient account provides the best explanation of the effect. We argue that future work should consider attention capture and orienting as a potential contributing factor to action observation effects more broadly.

How modality processing differences affect cross-modal nonspatial repetition inhibition

Although previous studies have demonstrated that identity-based repetition inhibition could occur across modalities, whether the modality processing difference or attentional set caused differences between the unimodal and cross-modal conditions was unknown. To investigate this question in both visual-auditory and auditory-visual patterns, the present study adopted a cross-modal "prime-neutral cue-target" priming paradigm, in which a neutral event was presented between the prime and the target. The relationships of the identities and modalities between the prime and the target were manipulated such that their modalities and identities could either be the same or different. Our results showed that (a) identity-based repetition inhibition occurred under both unimodal and cross-modal conditions, (b) response times to auditory targets were slower than those to visual targets, and (c) identity-based repetition inhibition was larger while discriminating repeated auditory targets than visual targets regardless of whether the prime was visual or auditory. These results suggested that nonspatial repetition inhibition can occur across modalities and that it was not in general larger or smaller than unimodal repetition inhibition, as this difference was due to modality processing differences.

Different visual and auditory latencies affect cross-modal non-spatial repetition inhibition

The present study examined the effect of different latencies for processing visual and auditory stimuli in cross-modal non-spatial repetition inhibition. In two experiments, the cue validity of modality and identity between the prime and the target was manipulated in a "prime-neutral cue-target" paradigm. A distinct neutral event was presented after the prime and before the onset of the target. The prime probe was visual in Experiment 1 and auditory in Experiment 2. The results in both experiments showed that RTs for identity-cued trials were significantly slower than RTs for identity-cued trials regardless of whether the modality of the target was visual or auditory. In addition, RTs for visual trials were significantly faster than RTs for auditory trials, indicating different latencies of processing visual and auditory stimuli. This latency difference affects cross-modal non-spatial repetition inhibition in two aspects: 1) creating a new representation (identity uncued) that is delivered via visual modality is easier under audio-visual conditions, and 2) retrieving an inhibited representation (identity cued) that is delivered via auditory modality is more difficult under visual-audio conditions. We propose that cross-modal non-spatial repetition inhibition, which is distinct from unimodal repetition inhibition, can be easily influenced by different latencies of processing visual and auditory stimuli.

Response inhibition immediately elicits negative affect and devalues associated stimuli: Evidence from facial electromyography

Response inhibition negatively impacts the emotional and motivational significance of associated stimuli. Current accounts question whether this stimulus devaluation effect occurs immediately via negative affect elicited by inhibition, or only occurs later via a misattribution of decreased fluency as unpleasantness in the context of an explicit affective-evaluation task. Using facial electromyography, we recorded indirect physiological markers of affective response during a response-inhibition (Go/No-go) task to test opposing predictions arising from the immediate-affect and delayed-misattribution hypotheses. Engagement of the corrugator supercilli-a muscle closely associated with negative affect-was greater during periods when response inhibition was applied (No-go trials) than when not applied (Go trials). Moreover, corrugator engagement during response-inhibition predicted the magnitude of stimulus devaluation measured behaviorally in subsequent subjective ratings (How cheerful?), with greater engagement during No-go trials that contained abstract-art stimuli later rated negatively than during trials that contained items later rated positively. These results support the immediate-affect hypothesis and converge with prior neuroimaging evidence to suggest that the negative impact of inhibition promptly alters the coding of stimulus value. In contrast, none of the delayed-misattribution based predictions were confirmed.

What does the dot-probe task measure? A reverse correlation analysis of electrocortical activity

The dot-probe task is considered a gold standard for assessing the intrinsic attentive selection of one of two lateralized visual cues, measured by the response time to a subsequent, lateralized response probe. However, this task has recently been associated with poor reliability and conflicting results. To resolve these discrepancies, we tested the underlying assumption of the dot-probe task-that fast probe responses index heightened cue selection-using an electrophysiological measure of selective attention. Specifically, we used a reverse correlation approach in combination with frequency-tagged steady-state visual potentials (ssVEPs). Twenty-one participants completed a modified dot-probe task in which each member of a pair of lateralized face cues, varying in emotional expression (angry-angry, neutral-angry, neutral-neutral), flickered at one of two frequencies (15 or 20 Hz), to evoke ssVEPs. One cue was then replaced by a response probe, and participants indicated the probe orientation (0° or 90°). We analyzed the ssVEP evoked by the cues as a function of response speed to the subsequent probe (i.e., a reverse correlation analysis). Electrophysiological measures of cue processing varied with probe hemifield location: Faster responses to left probes were associated with weak amplification of the preceding left cue, apparent only in a median split analysis. By contrast, faster responses to right probes were systematically and parametrically predicted by diminished visuocortical selection of the preceding right cue. Together, these findings highlight the poor validity of the dot-probe task, in terms of quantifying intrinsic, nondirected attentive selection irrespective of probe/cue location.

Long-Term Inhibition of Return for Spatial Locations: Evidence for a Memory Retrieval Account

It has generally been accepted that attention is inhibited from returning to previously attended locations, and that this inhibition of return (IOR) lasts just two or three seconds. Recently, Tipper, Grison, and Kessler (2003) showed that IOR can occur over much longer periods of time provided the inhibition is encoded with a context-rich event. Here we examine standard (i.e., typical time range) and long-term IOR within the same experimental paradigm as a means to compare their properties. Experiment 1 used the simple displays typical of cueing paradigms and revealed that both standard and long-term IOR can be obtained under such conditions. Experiment 2 showed that both standard and long-term IOR occurred when there was incongruence between the required response on the current trial and that stored in memory. Furthermore, IOR was not produced when there was incongruence between a target feature (colour) of the current trial and that stored in memory. These results are consistent with a memory retrieval account of IOR and suggest that the same inhibitory mechanism may underlie both standard and long-term IOR.

Reprint of: Object-based attentional facilitation and inhibition are neuropsychologically dissociated

Salient peripheral cues produce a transient shift of attention which is superseded by a sustained inhibitory effect. Cueing part of an object produces an inhibitory cueing effect (ICE) that spreads throughout the object. In dynamic scenes the ICE stays with objects as they move. We examined object-centred attentional facilitation and inhibition in a patient with visual form agnosia. There was no evidence of object-centred attentional facilitation. In contrast, object-centred ICE was observed in 3 out of 4 tasks. These inhibitory effects were strongest where cues to objecthood were highly salient. These data are evidence of a neuropsychological dissociation between the facilitatory and inhibitory effects of attentional cueing. From a theoretical perspective the findings suggest that 'grouped arrays' are sufficient for object-based inhibition, but insufficient to generate object-centred attentional facilitation.

Impaired memory for material related to a problem solved prior to encoding: suppression at learning or interference at recall?

Earlier research by the author revealed that material encoded incidentally in a speeded affective classification task and related to the demands of a divergent problem tends to be recalled worse in participants who solved the problem prior to encoding than in participants in the control, no-problem condition. The aim of the present experiment was to replicate this effect with a new, size-comparison orienting task, and to test for possible mechanisms of impaired recall. Participants either solved a problem before the orienting task or not, and classified each item in this task either once or three times. There was a reliable effect of impaired recall of problem-related items in the repetition condition, but not in the no-repetition condition. Solving the problem did not influence repetition priming for these items. These results support an account that attributes the impaired recall to inhibitory processes at learning and speak against a proactive interference explanation. However, they can be also accommodated by an account that refers to inefficient context cues and competitor interference at retrieval.

Attentional modulation of the carry over of eye-movements between tasks

Task demands that influence scanning behaviour in one task can cause that behaviour to persist to a second unrelated task (carry over). This can also affect performance on a second task (e.g., hazard perception ratings), and has been attributed to a process of attentional bias that is modulated by top-down influences (Thompson & Crundall, 2011). In a series of experiments we explored how these top-down influences impact upon carry over. In all experiments, participants searched letters that were presented horizontally, vertically, or in a random array. They were then presented with a driving scene and rated the hazardousness of the scene. Carry over of eye-movements from the letter search to the scene was observed in all experiments. Furthermore, it was demonstrated that this carry over effect influenced hazard perception accuracy. The magnitude of carry over was correlated with task switching abilities, attentional conflicting, and attentional orienting (Experiment 1), and was affected by predictability of the primary task (Experiment 2). Furthermore, direct current stimulation of the left dorsolateral prefrontal cortex and parietal areas affected the magnitude of the effect (Experiment 3). These results indicate that carry over is modulated by the specific ability to orient attention and disengage from this orientation. Over orienting leads to increased carry over and insufficient task switching is detrimental to task performance. As a result the current experiments provide evidence that the carry over effect is strongly influenced by attentional processes, namely orienting, inhibition, and task switching.

Negative priming 1985 to 2015: a measure of inhibition, the emergence of alternative accounts, and the multiple process challenge

In this article, three generations of authors describe the background to the original article; the subsequent emergence of vigorous debates concerning what negative priming actually reflects, where radically different accounts based on memory retrieval were proposed; and a re-casting of the conceptual issues underlying studies of negative priming. What started as a simple observation (slowed reaction times) and mechanism (distractor inhibition) appears now to be best explained by a multiple mechanism account involving both episodic binding and retrieval processes as well as an inhibitory process. Emerging evidence from converging techniques such as functional magnetic resonance imaging (fMRI), and especially electroencephalography (EEG), is beginning to identify these different processes. The past 30 years of negative priming experiments has revealed the dynamic and complex cognitive processes that mediate what appear to be apparently simple behavioural effects.

Dissociable identity- and modality-specific neural representations as revealed by cross-modal nonspatial inhibition of return

There are ongoing debates on whether object concepts are coded as supramodal identity-based or modality-specific representations in the human brain. In this fMRI study, we adopted a cross-modal "prime-neutral cue-target" semantic priming paradigm, in which the prime-target relationship was manipulated along both the identity and the modality dimensions. The prime and the target could refer to either the same or different semantic identities, and could be delivered via either the same or different sensory modalities. By calculating the main effects and interactions of this 2 (identity cue validity: "Identity_Cued" vs. "Identity_Uncued") × 2 (modality cue validity: "Modality_Cued" vs. "Modality_Uncued") factorial design, we aimed at dissociating three neural networks involved in creating novel identity-specific representations independent of sensory modality, in creating modality-specific representations independent of semantic identity, and in evaluating changes of an object along both the identity and the modality dimensions, respectively. Our results suggested that bilateral lateral occipital cortex was involved in creating a new supramodal semantic representation irrespective of the input modality, left dorsal premotor cortex, and left intraparietal sulcus were involved in creating a new modality-specific representation irrespective of its semantic identity, and bilateral superior temporal sulcus was involved in creating a representation when the identity and modality properties were both cued or both uncued. In addition, right inferior frontal gyrus showed enhanced neural activity only when both the identity and the modality of the target were new, indicating its functional role in novelty detection.

Cognition-emotion interactions are modulated by working memory capacity in individuals with schizophrenia

Prior research provides evidence for aberrant cognition-emotion interactions in schizophrenia. In the current study, we aimed to extend these findings by administering the "distractor devaluation" task to 40 individuals with schizophrenia and 32 demographically matched healthy controls. The task consisted of a simple visual search task for neutral faces, followed by an evaluative response made for one of the search items (or a novel item) to determine whether prior attentional selection results in a devaluation of a previously unattended stimulus. We also manipulated working memory demands by preceding the search array with a memory array that required subjects to hold 0, 1, or 2 items in working memory while performing the search array and devaluation task, to determine whether the normative process by which attentional states influence evaluative response is limited by working memory capacity. Results indicated that individuals with schizophrenia demonstrated the typical distractor devaluation effect at working memory load 0, suggesting intact evaluative response. However, the devaluation effect was absent at working memory loads of 1 and 2, suggesting that normal evaluative responses can be abolished in people with schizophrenia when working memory capacity is exceeded. Thus, findings provide further evidence for normal evaluative response in schizophrenia, but clarify that these normal experiences may not hold when working memory demands are too high.

In Support of a Distinction between Voluntary and Stimulus-Driven Control: A Review of the Literature on Proportion Congruent Effects

Cognitive control is by now a large umbrella term referring collectively to multiple processes that plan and coordinate actions to meet task goals. A common feature of paradigms that engage cognitive control is the task requirement to select relevant information despite a habitual tendency (or bias) to select goal-irrelevant information. At least since the 1970s, researchers have employed proportion congruent (PC) manipulations to experimentally establish selection biases and evaluate the mechanisms used to control attention. PC manipulations vary the frequency with which irrelevant information conflicts (i.e., is incongruent) with relevant information. The purpose of this review is to summarize the growing body of literature on PC effects across selective attention paradigms, beginning first with Stroop, and then describing parallel effects in flanker and task-switching paradigms. The review chronologically tracks the expansion of the PC manipulation from its initial implementation at the list-wide level, to more recent implementations at the item-specific and context-specific levels. An important theoretical aim is demonstrating that PC effects at different levels (e.g., list-wide vs. item or context-specific) support a distinction between voluntary forms of cognitive control, which operate based on anticipatory information, and relatively automatic or reflexive forms of cognitive control, which are rapidly triggered by the processing of particular stimuli or stimulus features. A further aim is to highlight those PC manipulations that allow researchers to dissociate stimulus-driven control from other stimulus-driven processes (e.g., S-R responding; episodic retrieval). We conclude by discussing the utility of PC manipulations for exploring the distinction between voluntary control and stimulus-driven control in other relevant paradigms.

Deficient inhibition of return in subclinical OCD only when attention is directed to the threatening aspects of a stimulus

BACKGROUND

Inhibition of return (IOR) is thought to reflect inhibition of previously attended but irrelevant stimuli. Deficient IOR would increase the likelihood of revisiting previously searched locations or objects, thus leading to unproductive perseverations.

METHOD

Therefore, using a novel IOR task, we investigated whether high scoring checkers attentional biases to threat would result in dysfunctional inhibitory functioning compared to low checkers. In two tasks, we compared 53 subclinical high and 49 low checkers regarding IOR effects for stimuli that were concordant with the concerns of high but not of low checkers (electrical kitchen appliances: e.g., toaster, kettle). The difference between the two tasks was the cueing procedure. In one task, an appliance was switched "ON" and "OFF" as an unpredictive cue, drawing attention to the functionality of the stimulus.

RESULTS

In this task, IOR was specifically attenuated in high checkers. In the other task, however, the cue was more abstract in form of a yellow outline that appeared around one of two appliances. Although the appliance was either "ON" or "OFF," this did not seem to matter and high checkers revealed a typical IOR pattern similar to low checkers.

CONCLUSIONS

We conclude that IOR mechanisms might not be generally deficient in high checkers; rather only when attention is drawn to the threatening aspects of ecologically valid stimuli, then disengagement of attention is deficient in high checkers. We make suggestions on how our task-specific findings may inform cognitive interventions that target attentional control in the treatment of checking/obsessive-compulsive disorder.

Social attention with real versus reel stimuli: toward an empirical approach to concerns about ecological validity

Cognitive neuroscientists often study social cognition by using simple but socially relevant stimuli, such as schematic faces or images of other people. Whilst this research is valuable, important aspects of genuine social encounters are absent from these studies, a fact that has recently drawn criticism. In the present review we argue for an empirical approach to the determination of the equivalence of different social stimuli. This approach involves the systematic comparison of different types of social stimuli ranging in their approximation to a real social interaction. In garnering support for this cognitive ethological approach, we focus on recent research in social attention that has involved stimuli ranging from simple schematic faces to real social interactions. We highlight both meaningful similarities and differences in various social attentional phenomena across these different types of social stimuli thus validating the utility of the research initiative. Furthermore, we argue that exploring these similarities and differences will provide new insights into social cognition and social neuroscience.

Context-specific control in the single-prime negative-priming procedure

The current paper examines the applicability of the context-specific control principle to the probe selection dependence of negative-priming effects using the single-prime procedure. In a series of experiments, we highlight the applicability of the context-specific control principle, first by illustrating a key result that implicates the role of context-specific control and challenges the contextual similarity principle. Following this, we show the importance of distinct probe contexts in the single-prime negative-priming procedure and report a novel finding that illustrates a learning effect that can occur within an experimental session. Finally, we test the relation of our novel learning effect to a related learning proposal offered by Frings and Wentura (2006), and we demonstrate that the learning involved in context-specific control is not dependent on contingency learning. Overall, the patterns of results highlight the role of context-sensitive memory in controlling how current perception and action are integrated with prior experience.

Context-specific control and the Stroop negative priming effect

The present study highlights the utility of context-specific learning for different probe types in accounting for the commonly observed dependence of negative priming on probe selection. Using a Stroop priming procedure, Experiments 1a and 1b offered a demonstration that Stroop priming effects can differ qualitatively for selection and no-selection probes when probe selection is manipulated between subjects, but not when it is manipulated randomly from trial to trial within subject (see also Moore, 1994). In Experiments 2 and 3, selection and no-selection probes served as two contexts that varied randomly from trial to trial, but for which proportion repeated was manipulated separately. A context-specific proportion repeated effect was observed in Experiment 2, characterized by modest quantitative shifts in the repetition effects as a function of the context-specific proportion repeated manipulation. However, with a longer intertrial interval in Experiment 3, a context-specific proportion repeated manipulation that focused on the no-selection probes changed the repetition effect qualitatively, from negative priming when the proportion repeated was .25 to positive priming when the proportion repeated was .75. The results are discussed with reference to the role of rapid, context-specific learning processes in the integration of prior experiences with current perception and action.

Famous faces demand attention due to reduced inhibitory processing

People have particular difficulty ignoring distractors that depict faces. This phenomenon has been attributed to the high level of biological significance that faces carry. The current study aimed to elucidate the mechanism by which faces gain processing priority. We used a focused attention paradigm that tracks the influence of a distractor over time and provides a measure of inhibitory processing. Upright famous faces served as test stimuli and inverted versions of the faces as well as upright non-face objects served as control stimuli. The results revealed that although all of the stimuli elicited similar levels of distraction, only inverted distractor faces and non-face objects elicited inhibitory effects. The lack of inhibitory effects for upright famous faces provides novel evidence that reduced inhibitory processing underlies the mandatory nature of face processing.

Gaze and arrow cueing of attention reveals individual differences along the autism spectrum as a function of target context

Observing averted gaze results in a reflexive shift of attention to the gazed-at location. In two experiments, participants scoring high and low on the Autism-Spectrum Quotient questionnaire (AQ; Baron-Cohen, Wheelwright, Skinner, Martin, & Clubley, 2001) observed arrow and gaze cues to investigate cueing effect magnitude as a function of the context in which peripheral targets could appear. While identical cueing effects were found with gaze and arrow cues, the more striking results concerned target stimuli. In Experiment 1, targets could appear on a peripheral face, or on scrambled face parts. Overall, greater cueing effects were found when the target appeared on a face. However, this face bias was only observed in participants with low AQ scores, whereas high AQ scorers oriented more to scrambled features. Experiment 2 found equal cueing to targets appearing on tools, as compared with tool parts. However, individual differences were again observed, where low AQ scorers showed larger cueing towards tools, while high scorers oriented more to scrambled parts, as in Experiment 1. These results support the idea that low AQ individuals orient strongly to objects attended by others. However, since the same results were found for arrow cues, this effect may generalize to all central cues to attention. High AQ scorers possessing many more autistic-like traits tended to orient more to scrambled shapes, perhaps reflecting a bias for orienting to local details.

From observation to action simulation: the role of attention, eye-gaze, emotion, and body state

This paper reviews recent aspects of my research. It focuses, first, on the idea that during the perception of objects and people, action-based representations are automatically activated and, second, that such action representations can feed back and influence the perception of people and objects. For example, when one is merely viewing an object such as a coffee cup, the action it affords, such as a reach to grasp, is activated even though there is no intention to act on the object. Similarly, when one is observing a person's behaviour, their actions are automatically simulated, and such action simulation can influence our perception of the person and the object with which they interacted. The experiments to be described investigate the role of attention in such vision-to-action processes, the effects of such processes on emotion, and the role of a perceiver's body state in their interpretation of visual stimuli.

Hemispheric Asymmetry in the Remapping and Maintenance of Visual Saliency Maps: A TMS Study

Parietal cortex has been implicated in the updating, after eye movements, of a salience map that is required for coherent visual experience and for the control of visually guided behavior. The current experiment investigated whether TMS over anterior intraparietal cortex (AIPCx), just after a saccade, would affect the ability to update and maintain a salience map. In order to generate a salience map, we employed a paradigm in which an uninformative cue was presented at one object in a display to generate inhibition of return (IOR)—an inhibitory tag that renders the cued object less salient than others in the display, and that slows subsequent responses to visual transients at its location. Following the cue, participants made a saccade to either left or right, and we then probed for updating of the location of IOR by measuring manual reaction time to targets appearing at cued location of the cued compared to an uncued object. Between the time of saccade initiation and target appearance, dual-pulse TMS was targeted over right (Experiment 1) or left AIPCx (Experiment 2), and a vertex control side. Updating of the location of IOR was eliminated by TMS over right, but not the left, AIPCx, suggesting that right parietal cortex is involved in the remapping of IOR. Remapping was eliminated by right AIPCx, regardless of whether the saccade was made to the left (contralateral), or right (ipsilateral) visual field, and regardless of which field the target appeared in. We conclude that right AIPCx is the neural substrate for maintaining a salience map across saccades, and not simply for propagating an efference copy of saccade commands.

Biasing the organism for novelty: A pervasive property of the attention system

Although the functional and anatomical independences between the orienting and the executive attention networks have been well established, surprisingly little is known about the potential neural interaction between them. Recent studies point out that spatial inhibition of return (IOR), a mechanism associated with the orienting network, and nonspatial inhibition of return, a mechanism associated with the executive network, might bias the organism for novel locations and objects, respectively. By orthogonally combining the spatial and the nonspatial IOR paradigms in this fMRI study, we demonstrate that the orienting and the executive networks interact and compensate each other in biasing the attention system for novelty. Behaviorally, participants responded slower to the target at the old location only when the color of the target was novel, and participants responded slower to the old color representation only when the target appeared at a novel spatial location. Neurally, the orienting network was involved in slowing down responses to the old location only when the nonspatial IOR mechanism in the executive network was not operative (i.e., when the color of the target was novel); the prefrontal executive network was involved in slowing down responses to the old color representation only when the spatial IOR mechanism in the orienting network was not functioning (i.e., when the target appeared at a novel location).

The effects of practice and external support on older adults' control of reflexive eye movements

The present study examined whether external support and practice could reduce age differences in oculomotor control. Participants were to avoid fixating an abrupt onset and on some trials, were provided with a predictive cue regarding the onset location or identity. Older adults demonstrated more capture than younger adults, but both groups improved with practice. Whereas the older group benefited from a location preview (Experiment 1), neither group showed less capture when given a preview of the onset object itself (Experiment 2), suggesting that location-based inhibition, but not object-based inhibition, was sufficient to support oculomotor control within this paradigm. To test the generalizability of these skills, displays in a final block were manipulated such that the onset could appear in a different location or be a different object altogether. Viewing patterns were similar for changed vs. unchanged displays, suggesting that participants' practice-related gains could withstand a change in the task materials.

Learning to Attend and to Ignore Is a Matter of Gains and Losses

Efficient goal-directed behavior in a crowded world is crucially mediated by visual selective attention (VSA), which regulates deployment of cognitive resources toward selected, behaviorally relevant visual objects. Acting as a filter on perceptual representations, VSA allows preferential processing of relevant objects and concurrently inhibits traces of irrelevant items, thus preventing harmful distraction. Recent evidence showed that monetary rewards for performance on VSA tasks strongly affect immediately subsequent deployment of attention; a typical aftereffect of VSA (negative priming) was found only following highly rewarded selections. Here we report a much more striking demonstration that the controlled delivery of monetary rewards also affects attentional processing several days later. Thus, the propensity to select or to ignore specific visual objects appears to be strongly biased by the more or less rewarding consequences of past attentional encounters with the same objects.

Distractor devaluation requires visual working memory

Visual stimuli seen previously as distractors in a visual search task are subsequently evaluated more negatively than those seen as targets. An attentional inhibition account for this distractor-devaluation effect posits that associative links between attentional inhibition and to-be-ignored stimuli are established during search, stored, and then later reinstantiated, implying that distractor devaluation may require visual working memory (WM) resources. To assess this, we measured distractor devaluation with and without a concurrent visual WM load. Participants viewed a memory array, performed a simple search task, evaluated one of the search items (or a novel item), and then viewed a memory test array. Although distractor devaluation was observed with low (and no) WM load, it was absent when WM load was increased. This result supports the notions that active association of current attentional states with stimuli requires WM and that memory for these associations plays a role in affective response.

Novelty Is Not Always the Best Policy

We report a study that examined whether inhibition of return (IOR) is specific to visual search or a general characteristic of visual behavior. Participants were shown a series of scenes and were asked to (a) search each scene for a target, (b) memorize each scene, (c) rate how pleasant each scene was, or (d) view each scene freely. An examination of saccadic reaction times to probes provided evidence of IOR during search: Participants were slower to look at probes at previously fixated locations than to look at probes at novel locations. For the other three conditions, however, the opposite pattern of results was observed: Participants were faster to look at probes at previously fixated locations than to look at probes at novel locations, a facilitation-of-return effect that has not been reported previously. These results demonstrate that IOR is a search-specific strategy and not a general characteristic of visual attention.

Exogenous Cuing of Distractor Location Facilitates Location Selection by Inhibition of Return

Attention capture by an exogenous cue can result in slowed responses to a target, which appeared at that cued location later. This is the phenomenon of inhibition of return (IOR). In the current study, the effect of IOR on performance in a location selection task was studied. A target and a distractor were presented at the same time, and the participants were instructed to indicate the location of the target by manual response. The results showed that it took longer to respond to the target at the cued location. More importantly, it took a shorter time to respond to the target when the distractor was presented at the cued location. These findings support the idea that IOR can facilitate performance in a target selection task if the distractor location is cued.

Automatic and controlled response inhibition: associative learning in the go/no-go and stop-signal paradigms

In 5 experiments, the authors examined the development of automatic response inhibition in the go/no-go paradigm and a modified version of the stop-signal paradigm. They hypothesized that automatic response inhibition may develop over practice when stimuli are consistently associated with stopping. All 5 experiments consisted of a training phase and a test phase in which the stimulus mapping was reversed for a subset of the stimuli. Consistent with the automatic-inhibition hypothesis, the authors found that responding in the test phase was slowed when the stimulus had been consistently associated with stopping in the training phase. In addition, they found that response inhibition benefited from consistent stimulus-stop associations. These findings suggest that response inhibition may rely on the retrieval of stimulus-stop associations after practice with consistent stimulus-stop mappings. Stimulus-stop mapping is typically consistent in the go/no-go paradigm, so automatic inhibition is likely to occur. However, stimulus-stop mapping is typically inconsistent in the stop-signal paradigm, so automatic inhibition is unlikely to occur. Thus, the results suggest that the two paradigms are not equivalent because they allow different kinds of response inhibition.

Location- and Object-Based Inhibition of Return are Affected by Different Kinds of Working Memory

Castel, Pratt, and Craik (2003) have shown that inhibition of return (IOR, the delayed response to a recently cued item) is disrupted by a secondary task that involves spatial working memory (WM), and they suggest that IOR is mediated by spatial WM. However, they did not specify what kind of IOR was involved. We used a dual-task paradigm to examine whether the two kinds of IOR (location- and object-based IOR) are affected by two kinds of secondary task that involve spatial and nonspatial WM, respectively. The results show that location-based IOR was disrupted by a spatial secondary task while the object-based IOR was disrupted by a nonspatial secondary task. The present study further elaborates the conclusion of Castel et al. (2003) by differentiating the effect of the two kinds of WM (spatial vs. nonspatial) on the two kinds of IOR (location based vs. object based).

Response inhibition is linked to emotional devaluation: behavioural and electrophysiological evidence

To study links between the inhibition of motor responses and emotional evaluation, we combined electrophysiological measures of prefrontal response inhibition with behavioural measures of affective evaluation. Participants first performed a Go–Nogo task in response to Asian and Caucasian faces (with race determining their Go or Nogo status), followed by a trustworthiness rating for each face. Faces previously seen as Nogo stimuli were rated as less trustworthy than previous Go stimuli. To study links between the efficiency of response inhibition in the Go–Nogo task and subsequent emotional evaluations, the Nogo N2 component was quantified separately for faces that were later judged to be high versus low in trustworthiness. Nogo N2 amplitudes were larger in response to low-rated as compared to high-rated faces, demonstrating that trial-by-trial variations in the efficiency of response inhibition triggered by Nogo faces, as measured by the Nogo N2 component, co-vary with their subsequent affective evaluation. These results suggest close links between inhibitory processes in top-down motor control and emotional responses.

Inhibition of return impairs episodic memory access

The term inhibition of return (IOR) refers to a bias against returning attention to a location or object that has recently been attended. The effect has been shown to occur in various perceptual tasks including stimulus detection, localization, and discrimination, but also to affect higher cognitive processes like lexical access. The present experiments examined whether inhibition of return would impair the high-level processing that is required in accessing item representations in episodic memory. The results show that reaction times for recognition memory decisions are increased under IOR. Furthermore, IOR affects the accuracy of recognition memory, and this effect interacts with the ease of memory access, manipulated, for example, by encoding depth in the learning phase. These results suggest that IOR impairs attentional processing up to the highest cognitive levels, including the access of prior item encounters in episodic memory.