Inhibition of return in children with Tourette's syndrome and comorbid forms: a preliminary study.

BACKGROUND: This study investigated the nature and functioning of the visual-spatial inhibition of return (IOR) phenomenon in children with "pure" Tourette's syndrome (TS), and those with comorbid forms of TS. METHOD: Children with TS-only and "TS + comorbid" (TS + ADHD +/- OCD) and matched controls performed the inhibition of return (IOR) task, which involved responding to left and right visual targets appearing on a computer screen that were preceded by congruent or incongruent exogenous visual cues. RESULTS: The TS-only group performed similarly on the IOR task to the controls. When the TS-only group was subdivided into children with mild and severe TS symptoms, a post hoc comparison between the controls and severe TS symptom children revealed that these TS children had a reduced magnitude of IOR for targets appearing in the right visual field. The comparison between the TS + comorbid and controls revealed an atypical IOR pattern for the TS + comorbid group. They displayed a loss of normal facilitatory and inhibitory effects for right visual field targets. CONCLUSIONS: The findings suggest abnormalities in attentional "disengage" and "move" mechanisms in TS when directing attention to the right visual field, which may reflect left posterior parietal, superior colliculus, and midbrain pathology.     

Emotional and hemispheric asymmetries in shifts of attention: An ERP study

Inhibition of return (IOR) refers to the larger response time to cued targets appearing at long cue-to-target intervals. Given emotion–attention interactions and associated visual field (VF) asymmetries, we examined the effects of emotions and hemispheric processing on object- and location-based IOR. We expected reduced IOR and right hemispheric bias accompanied by differences in event-related potentials (ERPs) including lack of suppression of cued N1 and enhancement of Nd components for sad targets. Reaction times and ERPs were recorded in an exogenous cuing detection task using happy and sad schematic faces. Results revealed reduced IOR for left compared to right VF with sad faces but no such asymmetry for happy faces. Cued N1 amplitudes were suppressed for happy targets but not for sad targets presented to the left VF. Nd amplitudes were enhanced for right-hemispheric sad faces especially with object-based IOR. The results indicate right-hemispheric advantage in the capture of attention by negative emotion especially with object-based selection.     

Emotional and hemispheric asymmetries in shifts of attention: an ERP study

Inhibition of return (IOR) refers to the larger response time to cued targets appearing at long cue-to-target intervals. Given emotion-attention interactions and associated visual field (VF) asymmetries, we examined the effects of emotions and hemispheric processing on object- and location-based IOR. We expected reduced IOR and right hemispheric bias accompanied by differences in event-related potentials (ERPs) including lack of suppression of cued N1 and enhancement of Nd components for sad targets. Reaction times and ERPs were recorded in an exogenous cuing detection task using happy and sad schematic faces. Results revealed reduced IOR for left compared to right VF with sad faces but no such asymmetry for happy faces. Cued N1 amplitudes were suppressed for happy targets but not for sad targets presented to the left VF. Nd amplitudes were enhanced for right-hemispheric sad faces especially with object-based IOR. The results indicate right-hemispheric advantage in the capture of attention by negative emotion especially with object-based selection.     

Inhibition of return in subliminal letter priming

The present study combined exogenous spatial cueing with masked repetition priming to study attentional influences on the processing of subliminal stimuli. Participants performed an alphabetic decision task (letter versus pseudo-letter classification) with central targets and briefly presented peripherally located primes that were either cued or not cued by an abrupt onset. A relatively long delay between cue and prime was used to investigate the effect of inhibition of return (IOR) on the processing of subliminal masked primes. Primes presented to the left visual field showed standard effects of Cue Validity and no IOR (significant priming with valid cues only). Primes presented to the right visual field showed no priming from valid cues (an IOR effect), and priming with invalid cues that depended on hand of response to letter targets (right-hand in Experiment 1, left-hand in Experiment 2). The results are interpreted in terms of a differential speed of engagement and disengagement of attention to the right and left visual fields for alphabetic stimuli, coupled with a complex interaction that arises between Prime Relatedness and response-hand.     

No evidence for directional biases in inhibition of return

The phenomenon of “inhibition of return” (IOR) has been the subject of considerable research interest for nearly 30 years. Two reports claiming directional biases in IOR (Spalek & Hammad, Perception & Psychophysics 66:219–233, 2004, Psychological Science 16:15–18, 2005) were examined more closely, as such findings challenge the theoretical role attributed to IOR and imply that this purported mechanism for the facilitation of visual search would bias search in systematic ways. The data from two new experiments, as well as reanalysis of the original data, showed the reports to result from an unconventional method of calculating IOR that confounded visual field with target location. Although we found significant differences in target detection response times between the visual fields, directional biases were absent from all of the examined data when the conventional method of computing IOR was applied.     

Inhibition of return in perception and action

Inhibition of return (IOR) refers to the delay in responses to previously cued locations. Whether IOR influences perceptual and/or motor processes has been controversial. To determine IOR effects on perception and action, this study examined IOR in spatially directed hand reaching (Experiment 1) and spatial localization of targets with a mouse cursor (i.e., an indirect visuomotor mapping/perceptual task; Experiment 2). The reaction times showed delayed responses for targets appearing within the whole cued hemifield for both tasks. However, hypometric spatial biases were consistently found only with directed reaching. Spatial biases in the mouse localization task were indirectly influenced by IOR and distinct from those in the reaching task. The dissociation in spatial characteristics for directed reaching vs. perception suggests that the effects of IOR are task dependent, but may be more directly linked to the dorsal motor system.     

Searching for inhibition of return in the rat using the covert orienting of attention task

Inhibition of return (IOR) is an important psychological construct describing inhibited responses to previously attended locations. In humans, it is investigated using Posner’s cueing paradigm. This paradigm requires central visual fixation and detection of cued stimuli to the left or right of the fixation point. Stimuli can be validly or invalidly cued, appearing in the same or opposite location to the cue. Although a rat version of the spatial cueing paradigm (the covert orienting of attention task) does exist, IOR has so far not been demonstrated. We therefore investigated whether IOR could be robustly demonstrated in adult male rats using the covert orienting of attention task. This task is conducted in holed wall operant chambers with the central three holes mimicking the set-up for Posner cueing. Across four samples of rats (overall n = 84), we manipulated the following task parameters: stimulus onset asynchronies (Experiments 1–3), cue brightness (Experiment 1b) and the presence of a central reorienting event (Experiment 4). In Experiment 1, we also investigated strain differences by comparing Lister Hooded rats to Sprague–Dawley rats. Although Lister Hooded rats briefly showed evidence of IOR (Experiment 1a, and see Online Resource 1 data), we were unable to replicate this finding in our other experiments using different samples of this strain. Taken together, our findings suggest that IOR cannot be robustly demonstrated in the rat using the covert orienting of attention task conducted in holed wall operant chambers.     

The effects of ignored versus foveated cues upon inhibition of return: An event-related potential study

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/perceptual flavor of IOR is recruited.     

The manifestation of attentional capture: facilitation or IOR depending on task demands

Orienting attention exogenously to a location can have two different consequences on processing subsequent stimuli appearing at that location: positive (facilitation) at short intervals and negative (inhibition of return) at long ones. In the present experiments, we manipulated the frequency of targets and responses associated with them. Results showed that, even at long SOAs, where IOR is usually observed, facilitation was observed for infrequent targets at the same time that IOR was measured for frequent targets. These results are difficult to explain on the basis of either task set modulation of attentional capture or task set modulation of subsequent orienting processes. In contrast, we offer an explanation by which the different cuing effects can be considered as different manifestations of attentional capture on target processing, depending on the task set.     

Oculomotor inhibition of return: Evidence against object-centered representation

ABSTRACT

Intermixing central, directional arrow targets with the peripheral targets typically used in the Posnerian spatial cueing paradigm offers a useful diagnostic for ascertaining the relative contributions of output and input processes to oculomotor inhibition of return (IOR). Here, we use this diagnostic to determine whether object-based oculomotor IOR comprises output and/or input processes. One of two placeholder objects in peripheral vision was cued, then both objects rotated smoothly either 90 or 180 degrees around the circumference of an imaginary circle. After this movement, a saccade was made to the location marked by a peripheral onset target or indicated by the central arrow. In our first three experiments, whereas there was evidence for IOR when measured by central arrow or peripheral onset targets at cued locations, there was little trace of IOR at the cued object. We thereafter precisely replicated the seminal experiment for object-based oculomotor IOR (Abrams, R. A., & Dobkin, R. S. (1994). Inhibition of return: Effects of attentional cuing on eye movement latencies. Journal of Experimental Psychology: Human Perception and Performance, 20(3), 467–477; Experiment 4) but again found little evidence of an object-based IOR effect. Finally, we ran a paradigm with only peripheral targets and with motion and stationary trials randomly intermixed. Here we again showed IOR at the cued location but not at the cued object. Together, the findings suggest that object-based representation of oculomotor IOR is much more tenuous than implied by the literature.     

返回抑制时程的三因素理论及其发展

综述了返回抑制(Inhibition of return,IOR)出现时程机制的三因素理论内容,支持该理论的实验证据,以及对理论的质疑和发展。该理论认为空间定向收益、出现检测缺失和空间选择收益三个因素共同决定了IOR出现的时程及机制。研究者通过操控任务加工水平或将实验范式相结合的方式对三因素理论提出了质疑和发展。许多关键问题如三个因素存在的认知神经科学证据、出现检测缺失和空间选择收益发挥作用的方式等是未来研究的重点和方向。     

Time processing in children with Tourette’s syndrome

Background

Tourette syndrome (TS) is characterized by dysfunctional connectivity between prefrontal cortex and sub-cortical structures, and altered meso-cortical and/or meso-striatal dopamine release. Since time processing is also regulated by fronto-striatal circuits and modulated by dopaminergic transmission, we hypothesized that time processing is abnormal in TS.

Methods

We compared time processing abilities between nine children with TS-only (i.e. without major psychiatric comorbidities) and 10 age-matched healthy children, employing a time reproduction task in which subjects actively reproduce different temporal intervals, and a time comparison task in which subjects judge whether a test interval is longer or shorter than a reference interval. IQ, sustained and divided attention, and working memory were assessed in both groups using the Leiter International Performance Scale-Revised, and the Digit Span sub-test of the WISC-R.

Results

Children with TS-only reproduced in an overestimated fashion over-second, but not sub-second, time intervals. The precision of over-second intervals reproduction correlated with tic severity, in that the lower the tic severity, the closer the reproduction of over-second time intervals to their real duration. Time reproduction performance did not significantly correlate with IQ, attention and working memory measures in both groups. No differences between groups were documented in the time comparison task.

Conclusions

The improvement of time processing in children with TS-only seems specific for the over-second range of intervals, consistent with an enhancement in the ‘cognitively controlled’ timing system, which mainly processes longer duration intervals, and depends upon dysfunctional connectivity between the basal ganglia and the dorso-lateral prefrontal cortex. The absence of between-group differences on time comparison, moreover, suggests that TS patients manifest a selective improvement of ‘motor’ timing abilities, rather than of perceptual time abilities. Our data also support an enhancement of cognitive control processes in TS children, probably facilitated by effortful tic suppression.     

Two spatially separated attention systems in the visual field: evidence from inhibition of return

It has been demonstrated that the human visual field shows some functional inhomogeneities, in particular when the central and perifoveal regions are compared to the more peripheral regions. The present study examined this inhomogeneity by examining the effect of stimulus eccentricity on inhibition of return (IOR), a phenomenon that biases our attention towards novel locations against returning it back to previously attended locations. Eighteen subjects were examined in a visual detection task, in which a target appeared randomly following a nonpredictive spatial cue in the visual field. The eccentricities of the cues and targets were systematically manipulated from 5° to 30° with 5° increments. Results showed that response times to targets that appeared at cued locations were significantly slower than those at uncued locations for all stimulus eccentricities, demonstrating the IOR effects. However, response times at cued locations increased significantly when stimulus eccentricity shifted from 15° to 20°, leading to a much stronger IOR effect at more peripheral regions compared to central and perifoveal regions, indicating a functional dissociation between these two regions of the visual field. Possible neural mechanisms underlying this dissociation are discussed, and two attention systems modulating the two functional regions of the visual field are put forward to best account the present finding implicating in particular midbrain mechanism.     

同时线索化条件下儿童返回抑制的容量

返回抑制是对先前注意过的目标再次做出反应的时候反应时延长的一种现象。返回抑制具有一定的生物学意义,忽略已经注意过的位置(或客体),使得有机体可以更加有效的注意新的内容。基于这一点,返回抑制现象应该可以在多个已经注意过的位置出现,这便是返回抑制的容量问题。在本研究中,采用同时呈现的线索化方式,考查8岁、10岁儿童在不同的实验任务——觉察任务和辨别任务——中的返回抑制容量。结果发现觉察任务中,10岁组儿童和8岁组儿童最多在5个线索化位置上出现返回抑制,但8岁年龄组的返回抑制容量缺乏稳定;辨别任务中,10岁年龄组只在一个位置上出现返回抑制,而8岁年龄组并没有明显返回抑制现象出现。年龄因素和任务类型对儿童返回抑制容量都产生了一定程度的影响。     

Increased visual bias in children with developmental coordination disorder: Evidence from a visual-tactile temporal order judgment task

BackgroundPrevious studies have suggested that children with developmental coordination disorder (DCD) rely heavily on vision to perform movements, which may contribute to their clumsy movements. However, few studies have objectively and quantitatively investigated the perceptual biases of children with DCD.MethodsA visual-tactile temporal order judgment (TOJ) task was used to measure and compare the perceptual biases of 19 children with DCD and 19 age- and sex-matched typically developing children. The point of subjective equality, which demonstrates when “visual first” and “tactile first” judgment probabilities are equal (50%), obtained by analyzing the results of the visual-tactile TOJ task, was used as an indicator of perceptual biases. Further, variables (age and manual dexterity in all participants; motor function, autism spectrum disorder and attention-deficit hyperactivity disorder traits, and depressive symptoms in children with DCD) associated with perceptual biases were examined with correlation analysis.ResultsChildren with DCD had significantly stronger visual bias than typically developing children. Overall correlation analysis showed that increased visual bias was significantly correlated with poor manual dexterity.ConclusionChildren with DCD had a strong visual bias, which was associated with poor manual dexterity.     

Effects of spatial cues on locating emotional targets

Inhibition of return (IOR) refers to slower responding to a visual target appearing at a previously cued versus uncued location. In three experiments, we asked whether IOR would be affected by the emotional content of target stimuli. Participants reported the location of negative (spiders, angry faces) or neutral (objects, neutral faces) targets as quickly and accurately as possible after a valid or invalid location cue (a simple circle). IOR was significantly smaller when detecting negative versus neutral targets, but only after repeated exposures to these stimuli (i.e., with blocked presentations). This effect was eliminated when target type was randomized within blocks. By presenting negative versus neutral targets in short alternating blocks and examining IOR on the first trial of each new block, we show that the emotional modulation of IOR stems from the affective context in place before visual orienting is initiated, not by perceptual processing of the target after cue offset.     

The spatial distribution of inhibition of return

Inhibition of return (IOR) refers to the finding that response times (RTs) are typically slower for targets at previously attended (cued) locations than for targets at novel (uncued) locations. Although previous research has indicated that IOR may spread beyond a cued location, the present study is the first to examine the spatial distribution of IOR with high spatial resolution over a large portion of the central visual field. This was done by using a typical IOR procedure (cue, delay, target) with 4 cue locations and 441 target locations (each separated by 1° of visual angle). The results indicate that IOR spreads beyond the cued location to affect the cued hemifield. However, the cues also produced a gradient of RTs throughout the visual field, with inhibition in the cued hemifield gradually giving way to facilitation in the hemifield opposite the cue.     

Experiencing the Cross-Sensory Error Signal During Movement Leads to Proprioceptive Recalibration

Abstract

Reaching to targets in a virtual reality environment with misaligned visual feedback of the hand results in changes in movements (visuomotor adaptation) and sense of felt hand position (proprioceptive recalibration). We asked if proprioceptive recalibration arises even when the misalignment between visual and proprioceptive estimates of hand position is only experienced during movement. Participants performed a “shooting task” through the targets with a cursor that was rotated 30° clockwise relative to hand motion. Results revealed that, following training on the shooting task, participants adapted their reaches to all targets by approximately 16° and recalibrated their sense of felt hand position by 8°. Thus, experiencing a sensory misalignment between visual and proprioceptive estimates of hand position during movement leads to proprioceptive recalibration.     

Inhibition of return in children and adolescents

Inhibition of return (IOR), slowed responding to targets at a cued location after attention is removed from this location, has been shown to occur both in adults and in infants. To explore suggestion that the timecourse of IOR depends on factors that might affect the efficiency with which attention is removed from the cued location, we compared the performance of young children (5-10-year-olds, N=49, M=8 years, 4 months) to older children and adolescents (11-17-year-olds, N=61, M=14 years) in single and double cue procedures. Cue-target interval was varied to measure the timecourse of IOR in this within-subjects localization task. Whereas no IOR was found in the young group unless a double cue procedure was used, in the older group, we found IOR at all intervals with the double cue procedure and the typical crossover pattern, with early facilitation followed by inhibition in the single cue procedure.     

Experience-guided attention: Uniform and implicit

Frequently finding a visual search target in one region of space induces a spatial attentional bias toward that region. Past studies on this effect typically tested fewer than 20 participants. The small sample prevents an investigation of two properties of learning: visual field uniformity and role of explicit awareness. Pooling data from multiple studies, here we examined location probability learning from ~120,000 visual search trials across 420 participants. Participants performed a serial search task. Unbeknownst to them, the target was disproportionately likely to appear in one visual quadrant. Location probability learning (LPL) was measured as the difference in reaction time to targets in the high-probability “rich” quadrant and the low-probability “sparse” quadrants. Results showed a lack of visual field effect. LPL was equivalent for “rich” quadrant in the upper left, upper right, lower left, and lower right. Learning did not induce a hotspot diagonal to the “rich” quadrant. To the contrary, RT was the longest in the diagonal quadrant. Recognition rate of the “rich” quadrant was above chance. However, recognition accuracy was unrelated to the size of LPL. Implicit learning induces visual-field-independent changes in spatial attention.