On the strategic modulation of the time course of facilitation and inhibition of return

In studies of exogenous attentional orienting, response times for targets at previously cued locations are often longer than those for targets at previously uncued locations. This effect is known widely as inhibition of return (IOR). There has been debate as to whether IOR can be observed in discrimination as well as detection tasks. The experiments reported here confirm that IOR can be observed when target discrimination is required and that the cue-target interval at which IOR is observed is often longer in discrimination than in detection tasks. The results also demonstrate that the later emergence of IOR is related to perceptual discrimination rather than to response selection differences between discrimination and detection tasks. More difficult discrimination tasks lengthen the SOA at which IOR emerges. In contrast, increasing task difficulty by adding a distractor to the location opposite the target shortens the SOA at which IOR emerges. Together, the results reveal an adaptive interaction between exogenous and endogenous attentional systems, in which the action of the orienting (exogenous) system is modulated endogenously in accord with task demands.     

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。     

Orienting of attention, pupil size, and the norepinephrine system

This research examined a novel suggestion regarding the involvement of the locus coeruleus-norepinephrine (LC-NE) system in orienting reflexive (exogenous) attention. A common procedure for studying exogenous orienting of attention is Posner's cuing task. Importantly, one can manipulate the required level of target processing by changing task requirements, which, in turn, can elicit a different time course of inhibition of return (IOR). An easy task (responding to target location) produces earlier onset IOR, whereas a demanding task (responding to target identity) produces later onset IOR. Aston-Jones and Cohen (Annual Review of Neuroscience, 28, 403-450, 2005) presented a theory suggesting two different modes of LC activity: tonic and phasic. Accordingly, we suggest that in the more demanding task, the LC-NE system is activated in phasic mode, and in the easier task, it is activated in tonic mode. This, in turn, influences the appearance of IOR. We examined this suggestion by measuring participants' pupil size, which has been demonstrated to correlate with the LC-NE system, while they performed cuing tasks. We found a response-locked phasic dilation of the pupil in the discrimination task, as compared with the localization task, which may reflect different firing modes of the LC-NE system during the two tasks. We also demonstrated a correlation between pupil size at the time of cue presentation and magnitude of IOR.     

On the uniqueness of attentional capture by uninformative gaze cues: facilitation interacts with the Simon effect and is rarely followed by IOR.

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

Does IOR occur in discrimination tasks? Yes, it does, but later

When a stimulus appears in a previously cued location several hundred milliseconds after the cue, the time required to detect that stimulus is greater than when it appears in an uncued location. This increase in detection time is known as inhibition of return (IOR). It has been suggested that IOR reflects the action of a general attentional mechanism that prevents attention from returning to previously explored loci. At the same time, the robustness of IOR has been recently disputed, given several failures to obtain the effect in tasks requiring discrimination rather than detection. In a series of eight experiments, we evaluated the differences between detection and discrimination tasks with regard to IOR. We found that IOR was consistently obtained with both tasks, although the temporal parameters required to observe IOR were different in detection and discrimination tasks. In our detection task, the effect appeared after a 400-msec delay between cue and target, and was still present after 1,300 msec. In our discrimination task, the effect appeared later and disappeared sooner. The implications of these data for theoretical accounts of IOR are discussed.     

注意定势及时间不确定性对基于空间的返回抑制的影响

在两个实验中使用比例控制范式 ,研究了基于空间位置的注意定势及时间不确定性对检测任务中IOR出现时程的影响。实验 1以 75名本科生为被试 ,将SOA水平作为组间变量 ,从而消除了时间不确定性。结果发现 ,当被试形成“更依赖于提示位置”的注意定势时 ,IOR出现的时程延长。实验 2以 2 2名本科生为被试 ,将SOA作为组内变量 ,从而将时间不确定性引入实验任务。结果表明 ,存在时间不确定性时 ,IOR出现的时程恢复到正常水平。两个实验的结果表明 ,IOR的时程受到内源和外源性注意之间交互作用的影响 ,而注意定势和时间不确定性是决定IOR何时出现及持续时间的两个十分关键的因素。     

动态情景中颜色特征和身份特征在返回抑制中的作用

在动态的“线索-靶子”范式中引入隧道刺激, 以靶子与线索的非空间特征相同时的反应延迟测量返回抑制效应。实验1利用单向隧道创设客体的空间位置信息明确且可靠的条件, 考察客体的颜色特征在返回抑制中的作用。实验2利用双向隧道创设客体的空间位置信息不明确的条件, 考察客体的颜色特征在返回抑制中的独立作用。实验3、4分别采用与实验1、2类似的方法, 在动态任务情景中考察客体的身份特征在返回抑制中的作用。结果显示, 线索呈现与靶子呈现的时间间隔较长时, 4个实验中均存在显著的返回抑制效应。这表明, 动态情景中, 客体的空间位置信息明确且可靠时, 颜色特征和身份特征在返回抑制中都发挥着重要作用; 客体的空间位置信息不明确时, 颜色特征和身份特征在返回抑制中也都具有相对独立的作用。     

Objects and their locations in exogenous cuing.

Anatomical, physiological, and behavioral studies provide support for separate object- and location-based components of visual attention. Although studies of object-based components have usually involved voluntary attention, more recent evidence has suggested that objects may play an independent role in reflexive exogenous orienting, at least at long stimulus onset asynchronies (SOAs). In the present experiments, the role of objects in reflexive attentional orienting was investigated by developing a task in which location and object cuing could be separately examined for both short and long SOAs. Typical location cuing effects were obtained, indicating facilitation at short cue-target intervals and inhibition of return (IOR) at longer intervals. In contrast, object cuing resulted in facilitation for cued objects at long cue-target intervals and no object-based IOR. Interestingly, object cuing primarily affected targets at cued locations, and not those at uncued locations. Together, the experiments examine the interactive nature of objects and locations in exogenous orienting and seem most consistent with a location-mediated view of object-based orienting.     

Cue and target processing modulate the onset of inhibition of return

Inhibition of return (IOR) is modulated by task set and appears later in discrimination tasks than in detection tasks. Several hypotheses have been suggested to account for this difference. We tested three of these hypotheses in two experiments by examining the influence of cue and target level of processing on the onset of IOR. In the first experiment, participants were required to respond to both the cue and target. The pattern of results showed that deeper processing of the cue or target advanced the onset of IOR. In the second experiment, participants were not required to respond to the cue and a reverse pattern of results emerged, which replicated the general findings in cuing tasks. We conclude that in more-demanding tasks, an additional process slows down the processing of a nonpredictive cue in order to enhance the processing of the target.     

任务难度对于返回抑制出现时间的影响

在返回抑制的范式下,以大学生为被斌,采用线索一靶子模式进行了两项实验.实施一发现,在觉察任务中,返回抑制在线索和靶子的时间间隔(SOA)为300ms时出现;在辨别任务中,返回抑制在SOA为700ms时出现.实验二发现在选择任务中,返回抑制在SOA为1300ms时出现.这些结果表明,随着实验任务的难度逐渐增大,返回抑制出现越来越晚.实验任务的难度是影响返回抑制出现时间的一个重要因素.     

任务需求对基于位置的返回抑制和基于颜色的重复劣势效应的影响

在 3个实验中探讨了任务需求对基于位置的返回抑制和基于颜色的重复劣势效应的影响。实验 1选取2 3名本科生被试 ,在把所有刺激都呈现在中央视觉上的颜色辨别任务中 ,发现颜色重复条件下的反应时明显长于非重复条件下的反应时 ,出现了显著的基于颜色的重复劣势效应 ,而且它的量显著大于简单检测任务中基于颜色的重复劣势效应量。实验 2和 3在实验 1的基础上加入空间不确定性 ,分别选取 2 2名和 2 3名本科生被试 ,并要求他们分别完成颜色辨别任务和简单检测任务。结果发现 ,在颜色辨别任务中 ,既获得了基于空间的返回抑制 ,又获得了基于颜色的重复劣势效应 ,而且二者之间没有交互作用 ,即它们各自独立地发挥作用 ;而在简单检测任务中 ,只获得了基于空间的返回抑制。 3个实验的结果表明 ,在一种实验情境下出现基于何种刺激特性的重复劣势效应 ,以及其量的大小完全取决于实验中的任务需求。在文章最后还将本研究结果与一种选择性注意领域内普遍抑制模型相结合 ,进行了深入讨论     

The relationship between inhibition of return and saccade trajectory deviations

After presentation of a peripheral cue, a subsequent saccade to the cued location is delayed (inhibition of return: IOR). Furthermore, saccades typically deviate away from the cued location. The present study examined the relationship between these inhibitory effects. IOR and saccade trajectory deviations were found after central (endogenous) and peripheral (exogenous) cuing of attention, and both effects were larger with an onset cue than with a color singleton cue. However, a dissociation in time course was found between IOR and saccade trajectory deviations. Saccade trajectory deviations occurred at short delays between the cue and the saccade, but IOR was found at longer delays. A model is proposed in which IOR is caused by inhibition applied to a preoculomotor attentional map, whereas saccade trajectory deviations are caused by inhibition applied to the saccade map, in which the final stage of oculomotor programming takes place.     

Objects and their locations in exogenous cuing

Anatomical, physiological, and behavioral studies provide support for separate object- and locationbased components of visual attention. Although studies of object-based components have usually involved voluntary attention, more recent evidence has suggested that objects may play an independent role in reflexiveexogenous orienting, at least at long stimulus onset asynchronies (SOAs). In the present experiments, the role of objects in reflexive attentional orienting was investigated by developing a task in which location and object cuing could be separately examined for both short and long SOAs. Typical location cuing effects were obtained, indicating facilitation at short cue—target intervals and inhibition of return (IOR) at longer intervals. In contrast, object cuing resulted in facilitation for cued objects at long cue—target intervals and no object-based IOR. Interestingly, object cuing primarily affected targets at cued locations, and not those at uncued locations. Together, the experiments examine the interactive nature of objects and locations in exogenous orienting and seem most consistent with a location-mediated view of object-based orienting.     

阈上和阈下不同情绪线索对返回抑制的影响

为检验返回抑制是否受线索生物学意义的调节, 分别在实验一和实验二中以阈上和阈下不同情绪效价(高兴、生气和中性)的面孔为外源性线索, 变化同时提示位置的多寡, 要求被试对靶子尽可能快而准地作探测反应。实验一发现, 三种线索情况下均出现返回抑制且效应量无显著差异; 实验二发现, 线索为中性面孔时出现返回抑制, 线索为高兴和生气面孔时未出现返回抑制。说明返回抑制受线索生物学意义的调节。阈下线索的生物学意义(情绪效价)能得到自动加工, 从而影响空间注意的转移和返回抑制机制的功用; 阈上线索的情绪效价被清晰感知时, 自上而下的注意控制机制使线索的生物学意义被忽略, 从而阻碍情绪效价功能的发挥。     

辨别作业难度对返回抑制时间进程的影响

在返回抑制范式下,利用线索一靶子模式和辨别作业进行了两个实验,探讨辨别作业难度对返回抑制的影响。以大学生为被试。实验一对辨别作业难度采用组间设计;实验二采用组内设计。结果发现,无论是组间比较(实验一),还是组内比较(实验二)．复杂辨别作业条件下返回抑制出现时间均比简单辨别作业晚,表明作业难度对返回抑制的时间进程有显著影响。该结果对返回抑制的机制研究有一定的意义。     

The involvement of bottom-up saliency processing in endogenous inhibition of return

Participants are faster at detecting a visual target when it appears at a cued, as compared with an uncued, location. In general, a reversal of this cost-benefit pattern is observed after exogenous cuing when the cue-target interval exceeds approximately 250?ms (inhibition of return [IOR]), and not after endogenous cuing. We suggest that, usually, no IOR is found with endogenous cues because no bottom-up saliency-based orienting processes are claimed. Therefore, we developed an endogenous feature-based split-cue task to allow for endogenous saliency-based orienting. IOR was observed in the saliency-driven endogenous cuing condition, and not in the control condition that prevented saliency-based orienting. These results suggest that usage of saliency-based orienting processes in either endogenous or exogenous orienting warrants the appearance of IOR.     

Temporal expectancy modulates inhibition of return in a discrimination task

This research examined the influence of cue temporal predictability on inhibition of return (IOR) in a discrimination task. In exogenous attention experiments, the cue that summons attention is noninformative as to where the target will appear. However, it is predictive as to when it will appear. In previous work, it was demonstrated that temporal predictability does not influence IOR in detection tasks. In this work, it is shown that IOR is influenced by temporal predictability in discrimination tasks. Predictability was manipulated by using three stimulus onset asynchrony distributions: nonaging, aging, and accelerated aging. IOR was found when the cue predicted target appearance and was modulated by temporal information. In the nonaging distribution (in which the cue did not predict target appearance), there was no IOR.     

Auditory frequency-based inhibition differs from spatial IOR

Uninformative auditory frequency cues have a facilitatory effect on reaction time and accuracy of detection and intensity discrimination of target tones for cue-target intervals of up to 3 sec (Green & McKeown, 2001; Ward, 1997). Under some conditions, however, this facilitatory effect can reverse to an inhibitory effect at cue-target intervals longer than 450 msec (Mondor, Breau, & Milliken, 1998). Thepresent work demonstrates that such inhibitory effects are not found in target-target experiments (Experiment 1) or in cue-target experiments requiring a go-no-go discrimination of the target (Experiment 2), whereas they do appear in the paradigm used by Mondor et al. (1998, Experiment 3), albeit unaffected by the similarity of cue and target. Thus, the frequency-based inhibitory effects sometimes found in auditory cuing tasks can be distinguished empirically from those characterizing spatial inhibition of return (IOR), which are found in both target-target and go-no-go cue-target paradigms. The present work and functional and neurophysiological arguments all support the position that different mechanisms underlie spatial IOR and the inhibitory effects sometimes found in auditory frequency processing.     

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。     

The effects of onsets and offsets on visual attention

 Two experiments are presented which examine the effect of onset and offset cues on early occurring attentional cueing effects and later occurring inhibition of return (IOR). The first experiment compared the effects of single onset cues, single offset cues, and simultaneous onset and offset cues (at opposite locations) at a 100-ms stimulus-onset-asynchrony (SOA) and IOR at a 900-ms SOA. Whereas the first experiment examined these conditions with choice localization keypress responses, the second experiment used simple detection keypress responses. Both experiments found that onset and offset cues presented in isolation produce early facilitation and late IOR. When onset and offset cues were simultaneously presented, facilitation but not IOR was found with localization responses, while neither facilitation or IOR was found with detection responses. Overall, these findings suggest that offset cues can be treated in the same manner as onset cues by the attentional system, although the onset cues may have priority in orienting attention when targets must be localized in space. Received: 26 May 2000 / Accepted: 31 January 2001