Inhibition of return in manual and saccadic response systems

When nonpredictive exogenous visual cues are used to reflexively orient covert visual spatial attention, the initial early facilitation for detecting stimuli at cued versus uncued spatial locations develops into inhibition by 300 msec following the cue, a pattern referred to as inhibition of return (IOR). Experiments were carried out comparing the magnitude and time course for development of IOR effects when manual versus saccadic responses were required. The results showed that both manual and saccadic responses result in equivalent amounts of facilitation following initial exposure to a spatial cue. However, IOR developed more quickly for saccadic responses, such that, at certain cue-target SOAs, saccadic responses to targets were inhibited, whereas manual responses were still facilitated. The findings are interpreted in terms of a premotor theory of visual attention.     

The effect of the physical characteristics of cues and targets on facilitation and inhibition

The present experiment was conducted in order to examine the role of cue—target discriminability on early occurring attentional cuing effects and late occurring inhibition of return (IOR). The experiment used a single target stimulus in conjunction with three different cue stimuli. The cues were the same as the target, different in color, shape, and luminance to the target, or did not spatially overlap with the target. At shorter stimulus onset asynchronies (SOAs; 100 and 200 msec), attentional cuing effects were only found with the nonoverlapping cues. However, at longer SOAs (400 and 800 msec), approximately equal IOR effects were found with all three types of cues. The results indicated that the physical characteristics of the cues and targets affected the pattern of reaction times at the shorter SOAs but not at the longer SOAs. The conclusion is that the biphasic pattern of early facilitation and late inhibition following a peripheral cue should not be considered the definitive signature of the peripheral cuing paradigm.     

On the causes and effects of inhibition of return

Unpredictive visual transient cues have a biphasic effect on reaction times (RTs) to peripheral onset targets. At relatively short (e.g., 150-msec) cue-target stimulus onset asynchronies (SOAs), RTs to targets at cued versus uncued locations are facilitated, whereas at relatively long SOAs (e.g., beyond 300 msec), they are inhibited. The present review explores the conditions under which this latter, inhibitory, effect-referred to as inhibition of return (IOR; Posner & Cohen, 1984)—is revealed and those conditions under which it is generated. We argue that the extant literature converges on the view that IOR reflects a motor response bias that is generated by the activation of an oculomotor program to fixate the cue. However, we reveal that current conceptualizations of IOR are based on a limited sampling of possible tests of the generation and measurement of IOR and indicate where further experimental research is critical.     

Disinhibition of return: Unnecessary and unlikely

Recently, from data obtained with a temporal order judgment (TOJ) task, Gibson and Egeth (1994) concluded that inhibition of return (IOR; a response time effect that reveals slower responding to targets at previously cued versus uncued locations) reflects impaired perceptual processing. By replotting their data, we demonstrate that the perception of temporal order is influenced only by the facilitatory effect of a cue at short stimulus onset asynchronies (SOAs) and is unaffected by IOR at long SO As. The target paper proposed that, when extra stimuli are presented at task-relevant locations (i.e., in the TOJ task), IOR is prevented by a hypothetical process that is known as disinhibition of return (DOR). We argue that the assumptions that IOR affects perceptual processing and that DOR exists are unnecessary, as a more parsimonious response-based interpretation of IOR is consistent with their data. Further, we summarize recent results and present new data that demonstrate that DOR is unlikely.     

Effects of contrast polarity in paracontrast masking

The visibility of a target stimulus can be suppressed (inhibition) or increased (facilitation) during paracontrast masking. Three processes have been proposed to be involved in paracontrast masking: brief inhibition, facilitation, and prolonged inhibition (Breitmeyer et al., 2006). Brief inhibition is observed when the mask precedes the target at short stimulus onset asynchronies (SOAs) ranging from -10 to -30 msec, whereas prolonged inhibition is effective up to very large SOAs of -450 msec. Facilitation, enhancement in target visibility, can be observed at SOA values between -20 and -110 msec. We further investigated these processes by changing target-mask spatial separation and the contrast polarity of the mask. Our results show that (1) facilitation weakens when spatial separation between the target and mask is increased or when they have opposite contrast polarity, and (2) brief inhibition turns into facilitation for the opposite-polarity mask, whereas prolonged inhibition does not change significantly. These results suggest a fast inhibition mechanism realized in the contrast-specific center-surround antagonism of classical receptive fields for brief inhibition and a slower, higher level cortical processing that is indifferent to contrast polarity for prolonged inhibition.     

Bidirectional semantic priming in the attentional blink

The time course of semantic priming between two associated words was tracked using rapid serial visual presentation of two synchronized streams of stimuli appearing at about 20 items/sec, each stream including a target word. The two words were semantically related or unrelated and were separated by stimulus onset asynchronies (SOAs) of 0–213 msec. Accuracy in reporting the first target (T1) versus the second target (T2) has been shown to interact dramatically with SOA over this range. The materials were in English in Experiment1 and Italian in Experiment2. T1 was semantically primed only at short SOAs, whereas T2 was primed at all SOAs (Experiment 1) or at all SOAs except the shortest one (Experiment2). The results indicate a strong competition between target words early in processing, with T2 often becoming the first word identified at short SOAs, thus priming T1.     

Timing of reflexive visuospatial orienting in young, young-old, and old-old adults

This study examined adult age differences in reflexive orienting to two types of uninformative spatial cues: central arrows and peripheral onsets. In two experiments using a Posner cuing task, young adults (ages 18–28 years), young-old adults (60–74 years), and old-old adults (75–92 years) responded to targets that were preceded 100–1,000 ms earlier by a central arrow or a peripheral abrupt onset. In Experiment 1, the cue remained present upon target onset. Facilitation effects at short cue–target stimulus onset asynchronies (SOAs) were prolonged in duration for the two older groups relative to the young adults. At longer cue–target SOAs, inhibition of return (IOR) that was initiated by peripheral onset cues was observed in the performance of young adults but not in that of the two older groups. In Experiment 2, the cue was presented briefly and removed prior to target onset. The change in cue duration minimized age differences (particularly for young-old adults) in facilitation effects and led to IOR for all three age groups. The findings are consistent with the idea that attentional control settings change with age, with higher settings for older adults leading to delayed disengagement from spatial cues.     

Developmental aspects of dichoptic viewing

Age-related performance changes on a dichoptic viewing task were examined with twenty-five (25) individuals in a cross-sectional design. Using a double-report procedure, subjects were asked to identify two different consonant-vowel graphemes presented separately to the same foveal area of each eye (i.e., dichoptic stimulation). Stimuli were presented at stimulus-onset asynchronies (SOAs) ranging from 0 to 300 msec in 50-msec steps. Results indicated that the number of both-correct trials (i.e., correct reports of both stimuli in a dichoptic pair) significantly increased with age, while single-correct trials (a correct report of only one stimulus in the pair) significantly decreased with age. In addition, the shape of the masking functions indicated lagging stimuli were reported more accurately than leading stimuli at SOAs of 50–300 msec for all subjects. Younger subjects exhibited peak masking effects for synchronous presentations (0-msec SOA) while older individuals showed peak masking at SOAs of 50 msec. Results suggest developmental performance changes noted in processing visual information parallel, to a remarkable degree, those observed in processing auditory information.     

Long-term facilitation of return: A response-retrieval effect

The present study used a target–target procedure to examine the extent to which perceptual and response factors contribute to inhibition of return (IOR) in a visual discrimination task. When the target was perceptually identical to the previous target and the required response was the same, facilitation was observed for both standard and long-term target–target stimulus onset asynchronies (SOAs). When the color of the previous target differed from that of the current target but the response remained the same, facilitation was reduced in both the standard SOA and long-term SOA conditions. Finally, IOR was observed for both standard and long-term SOAs only in the condition in which there was a change in response. This pattern of inhibition and facilitation provides new evidence that the responses previously associated with a location play an important role in the ability to respond to a stimulus. We interpret this finding as consistent with a framework in which the involuntary retrieval of bound stimulus–response episodes contributes to response compatibility effects in visual stimulus discrimination.     

Facilitation and inhibition caused by the orienting of attention in propositional reasoning tasks

In an attempt to study the orienting of attention in reasoning, we developed a set of propositional reasoning tasks structurally similar to Posner's (1980) spatial cueing paradigm, widely used to study the orienting of attention in perceptual tasks. We cued the representation in working memory of a reasoning premise, observing whether inferences drawn using that premise or a different, uncued one were facilitated, hindered, or unaffected. The results of Experiments 1a, 1b, 1c, and 1d, using semantically (1a–1c) or statistically (1d) informative cues, showed a robust, long-lasting facilitation for drawing inferences from the cued rule. In Experiment 2, using uninformative cues, inferences from the cued rule were facilitated with a short stimulus onset asynchrony (SOA), whereas they were delayed when the SOA was longer, an effect that is similar to the “inhibition of return” (IOR) in perceptual tasks. Experiment 3 used uninformative cues, three different SOAs, and inferential rules with disjunctive antecedents, replicating the IOR-like effect with the long SOAs and, at the short SOA, finding evidence of a gradient-like behaviour of the facilitation effect. Our findings show qualitative similarities to some effects typically observed in the orienting of visual attention, although the tasks did not involve spatial orienting.     

Inhibition of return lasts longer at repeatedly stimulated locations than at novel locations

Inhibition of return (IOR) refers to the fact that it takes longer for people to attend to recently examined locations than to novel locations. It has been argued that a single mechanism governs both IOR and negative priming (NP). If this is true, IOR and NP should share similar characteristics. Since NP depends on the use of repeated stimuli, in this study the dependence of IOR on repeated stimuli was explored. Experiments 1A—1D showed that, at longer cue-to-target-onset asynchrony (CTOA) intervals (613 and 906 msec), IOR could be observed only at repeatedly stimulated locations. However, IOR was observed when CTOA was short (253 msec) regardless of stimulus repetition. Experiments 2 and 3 replicated Experiments 1A—1D with a within-subjects design. The important role of memory representations in IOR is proposed.     

Facilitation and inhibition caused by the orienting of attention in propositional reasoning tasks

In an attempt to study the orienting of attention in reasoning, we developed a set of propositional reasoning tasks structurally similar to Posner's (1980) spatial cueing paradigm, widely used to study the orienting of attention in perceptual tasks. We cued the representation in working memory of a reasoning premise, observing whether inferences drawn using that premise or a different, uncued one were facilitated, hindered, or unaffected. The results of Experiments 1a, 1b, 1c, and 1d, using semantically (1a-1c) or statistically (1d) informative cues, showed a robust, long-lasting facilitation for drawing inferences from the cued rule. In Experiment 2, using uninformative cues, inferences from the cued rule were facilitated with a short stimulus onset asynchrony (SOA), whereas they were delayed when the SOA was longer, an effect that is similar to the “inhibition of return” (IOR) in perceptual tasks. Experiment 3 used uninformative cues, three different SOAs, and inferential rules with disjunctive antecedents, replicating the IOR-like effect with the long SOAs and, at the short SOA, finding evidence of a gradient-like behaviour of the facilitation effect. Our findings show qualitative similarities to some effects typically observed in the orienting of visual attention, although the tasks did not involve spatial orienting.     

Time course of priming for associate and inference words in a discourse context

The construction of word meanings in a discourse context was conceptualized as a process of sense activation, sense selection, and sense elaboration. In three experiments, subjects read texts presented by a rapid serial visual procedure and performed a lexical decision on visually presented targets that followed ambiguous prime words. When the target was a word, it was either an associate of the prime word, a probable inference suggested by the discourse, or an unrelated word. For associates, lexical decisions that related to either the appropriate or the inappropriate sense of the ambiguous word were generally facilitated at short (200-400 msec) prime-target stimulus onset asynchronies (SOAs). At longer SOAs, responses were faster to appropriate than to inappropriate associates. For the thematic inferences, there was no difference between these (appropriate) inferences and (inappropriate) control words at short SOAs. At long SOAs (1,000 and 1,500 msec), however, inference words were facilitated. The results are interpreted as consistent with a model of lexical processing in which sense activation functions independently of context. Discourse context effects, whether on sense selection (suppression of inappropriate associates) or on sense elaboration (creation of inferences), are seen as postlexical.     

The global precedence effect is not affected in inhibition of return

This study assessed whether inhibitory processes occurring in IOR affect perceptual processing of hierarchically organised stimuli. Experiment 1 used a global/local task that presented stimuli to the left or the right side. Results showed a global task advantage and a larger interference in the local than in the global task—the global precedence effect (GPE). These effects were larger than in previous studies using centrally presented stimuli, which suggests a greater involvement of low spatial frequency analysis with peripheral than with central stimuli. Experiment 2 combined the global/local task with IOR. Results replicated those of Experiment 1 but there was no interaction with stimulus location. That is, the GPE was not affected in IOR. Thus, we conclude that the GPE and inhibitory processing occurring in IOR are subserved by different mechanisms.     

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.     

Inhibition of return for the length of a line?

Inhibition of return is most often measured using an exogenous spatial cuing method. The experiments presented here follow up on a small number of studies that have examined whether a similar effect occurs for nonspatial stimulus attributes. In Experiments 1 and 2, the task was to identify a target line as either short or long. In this context, targets on valid trials were of the same length as that of a preceding cue, whereas targets on invalid trials were of a different length than that of a preceding cue. The results were similar to those in spatial orienting studies in that responses were slower for valid than for invalid targets only at stimulus onset asynchronies (SOAs) longer than 300 msec. In Experiment 3, the stimuli were the same but the task was to detect the onset of the target line. This task change resulted in slower responses for valid than for invalid targets at all SOAs. A similar result was observed in Experiment 4, in which validity was defined by color rather than line length, and the task was to identify the target color. The discussion centers on an opponent process approach to interpreting cuing effects, and consequent difficulties in distinguishing spatial and nonspatial cuing effects based on their time course.     

Visual form integration and discontinuity detection

Two experiments were conducted to determine if discontinuity detection limits the visual integration of two stimuli presented successively. If this is the case, then presenting two dim stimuli should permit better integration than presenting two bright stimuli. In Experiment 1, five observers named the position of the missing dot in a 5 x 5 dot matrix. Twelve randomly selected dots were presented in each of two stimulus presentations. The stimuli varied in intensity in a ratio of 15:1 and stimulus onset asynchrony (SOA) varied between 50 msec and 80 msec. At the longer SOAs, presenting two bright stimuli led to a higher percentage of correct responses than presenting two dim stimuli. There was no difference between those conditions at the shorter SOAs. In Experiment 2, 12 naive observers rated the amount of integration of the same stimuli on a 7-point scale, under the same presentation conditions. Rated integration was higher with two dim stimuli than with two bright stimuli. These apparently contradictory results are explained in terms of Hawkins and Shulman's distinction between two kinds of visual persistence. It is concluded that subjects can respond to integration and discontinuity detection separately. No evidence was found that discontinuity detection limits the integration.     

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。     

Inhibition of return is not detected using illusory line motion

Inhibition of return (IOR) is the name that has been assigned to a response time (RT) delay to a stimulus presented at a recently stimulated spatial location. A commonly held explanation for the origins of IOR is that perceptual processing is inhibited and that this inhibition translates into slower RT. Three experiments with 10 subjects were used to directly test this perceptual explanation. The first two experiments assessed the level of perceptual facilitation present in the IOR paradigm using the frequency and latency of illusory line motion judgments. Contrary to the predictions of the perceptual view, the line motion and RT measures revealed only speeded processing at previously stimulated spatial locations. Experiment 3 required a simple detection response and used the same stimulus and timing parameters as those in Experiments 1 and 2. IOR was present, replicating the recent finding that judgments based on perceptual qualities of the stimulus do not demonstrate a RT delay, whereas simple detection tasks do show RT inhibition at previously stimulated locations. These findings are discussed in relation to a number of hypotheses about the origin of the RT delay.     

面孔表情和声音情绪信息整合对返回抑制的影响

返回抑制(inhibition of return, IOR)与情绪刺激都具有引导注意偏向、提高搜索效率的特点, 但二者间是否存在一定的交互作用迄今为止尚不明确。研究采用“线索-目标”范式并在视听双通道呈现情绪刺激来考察情绪刺激的加工与IOR的交互作用。实验1中情绪刺激以单通道视觉面孔或一致的视听双通道呈现, 实验2通过在视听通道呈现不一致的情绪刺激进一步考察视听双通道情绪一致刺激对IOR的影响是否是由听觉通道一致的情绪刺激导致的, 即是否对听觉通道的情绪刺激进行了加工。结果发现, 视听双通道情绪一致刺激能够削弱IOR, 但情绪不一致刺激与IOR之间不存在交互作用, 并且单双通道的IOR不存在显著差异。研究结果表明仅在视听双通道呈现情绪一致刺激时, 才会影响同一阶段的IOR, 这进一步支持了IOR的知觉抑制理论。