Object- and location-based inhibition of return in younger and older adults.

When a cued object moves to new spatial coordinates, inhibition of return (IOR) with younger adults is found at the original cued location (location-based IOR) and at the current location of the object (object-based IOR). Older adults, however, show only location-based IOR. To determine whether this pattern of results represents a general age-related deficit in object-based IOR, the authors used static displays in which the placeholders (i.e., objects) were either present (location-based IOR + object-based IOR) or absent (location-based IOR only). Both age groups showed location-based IOR, but the older adults failed to show object-based IOR, consistent with age-related differences in visual pathways. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Examining the role of the fixation cue in inhibition of return.

To clarify the role of the fixation cue in inhibition of return (IOR), the present study compared four conditions: fixation cue immediately after the peripheral cue, in the middle of the stimulus-onset asynchrony (SOA), immediately before the onset of the target, or no fixation cue. With a 200-ms SOA, less IOR was found when the fixation cue was either absent or occurred immediately after the peripheral cue. No differences between the four conditions were found with 400-ms and 800-ms SOAs. These findings suggest that there is a brief period of time in which attention cannot be withdrawn from the peripherally cued location. Once attention has been withdrawn from the peripherally cued location, IOR can be found at short SOAs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of return and object-based attentional selection.

Visual attention research has revealed that attentional allocation can occur in space- and/or object-based coordinates. Using the direct and elegant design of R. Egly, J. Driver, and R. Rafal (1994), the present experiments tested whether space- and object-based inhibition of return (IOR) emerge under similar time courses. The experiments were capable of isolating both space- and object-based effects induced by peripheral and back-to-center cues. The results generally support the contention that spatially nonpredictive cues are effective in producing space-based IOR at a variety of stimulus onset asynchronies (SOAs) and under a variety of stimulus conditions. Whether facilitatory or inhibitory in direction, the object-based effects occurred over a very different time course than did the space-based effects. Reliable object-based IOR was only found under limited conditions and was tied to the time since the most recent cue (peripheral or central). The finding that object-based effects are generally determined by SOA from the most recent cue may help to resolve discrepancies in the IOR literature. These findings also have implications for the search facilitator role that IOR is purported to play in the guidance of visual attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related differences in object- and location-based inhibition of return of attention.

Four experiments examined age-related differences in inhibition of return (IOR) of visual attention. Using static stimuli, both young and older adults were slower to detect targets in previously cued objects, showing equivalent IOR. With objects that moved after they had been cued, young adults were slower to detect targets in the cued object (compared with uncued ones), revealing object-based IOR, but older adults were faster to detect targets in such objects, failing to demonstrate object-based IOR. Both age groups were slower to detect targets at the initially cued location (location-based IOR). The results show that age has a differential effect on IOR depending on the frame of reference of the inhibition: Inhibition for objects breaks down with age, but that for location does not. This pattern of results is consistent with the view that there are specific inhibitory deficits in old age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of return: Dissociating attentional and oculomotor components.

Inhibition of return (IOR) describes a performance decrement for stimuli appearing at recently cued locations. Both attentional and motor processes have been implicated in the IOR effect. The present data reveal a double dissociation between the attentional and motor components of IOR whereby the motor-based component of IOR is present when the response is oculomotor, and the attention-based component of IOR is present when the response is manual. These 2 distinct components should be considered and studied separately, as well as in relation to each other, if a comprehensive theory of IOR is to be achieved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Illusory recollection in older adults and younger adults under divided attention.

The authors investigated the effect of divided attention, study-list repetition, and age on recollection and familiarity. Older and younger adults under full attention and younger adults under divided attention at study viewed word lists highly associated with a single unstudied word (critical lure) once or three times, and subsequently performed a remember-know recognition test. Younger adults made fewer false remember responses to critical lures from repeated study lists, whereas younger adults under divided attention and older adults both showed an increase with repetition. Findings suggest older adults' susceptibility to illusory memories is related to a deficit in available attention during encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of return to social signals of fear.

The present study examined whether inhibition of return (IOR) is modulated by the fear relevance of the cue. Experiment 1 found similar magnitude of IOR was produced by neutral and fear faces and luminance matched cues. To allow a more sensitive measure of endogenously directed attention, Experiment 2 removed a central reorienting cue and more precisely measured the time course of IOR. At stimulus onset asynchronies (SOAs) of 500, 1,000 and 1,500 ms, fear face and luminance matched cues resulted in similar IOR. These findings suggest that IOR is triggered by event onsets and disregards event value. Views of IOR as an adaptive "foraging facilitator," whereby attention is guided to promote optimal sampling of important environmental events, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Examining Task Difficulty and the Time Course of Inhibition of Return: Detecting Perceptually Degraded Targets.

The ability to efficiently direct visual attention to salient features in the environment is a critical function of the visual system. The finding that people are slower to detect a target that appears at a previously cued location is thought to reflect a mechanism known as inhibition of return (IOR). Past research has shown that difficult target discriminations result in a greater amount of time needed to inhibit previously attended locations (i.e., a delayed onset of inhibition), suggesting that task difficulty plays a critical role in the allocation of attention. In this study, IOR was measured at a wide range of SOAs while participants detected either a perceptually degraded target or a standard, high luminance target. When responses were made to a perceptually degraded target, the time course of IOR was delayed by approximately 250 ms (relative to the control group), suggesting that the difficulty in detecting targets also influences the allocation of attention. The results are consistent with the notion that IOR is not simply a reflexive subcortical mechanism but rather involves top-down attentional control settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recreational use of cocaine eliminates inhibition of return.

Chronic and recreational use of cocaine has been shown to impair inhibitory output control (response inhibition) but whether input control is also affected is an open question. For the first time, this study compared the ability to perform a cued target-discrimination task that measured inhibition of return (IOR), a reflexive inhibitory mechanism that delays attention from returning to a previously attended location, in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, and level of intelligence. Results show that the recreational use of cocaine eliminates IOR, suggesting that input control is strongly impaired. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Context affects feeling-of-knowing accuracy in younger and older adults.

In feeling of knowing (FOK) studies, participants predict subsequent recognition memory performance on items that were initially encoded but that cannot presently be recalled. Research suggests that FOK judgment magnitude may be influenced by the total amount, or quantity, of contextual information retrieved related to the unrecalled target (e.g., Koriat, 1993). The present study examined the contribution of quality of that information to episodic FOK judgments. In addition, we tested whether the episodic FOK deficit demonstrated by older adults could be reduced by encouraging retrieval of contextual information relevant to the target. Three experiments demonstrated that quality of the retrieved partial information influenced FOK judgments in both older and younger adults; however, the manifestation of that influence was age dependent. The results also indicated that older adults required explicit retrieval of contextual information before making FOK judgments in order to make accurate FOK predictions. The results suggest that FOK accuracy may be partially determined by search processes triggered when participants are queried for contextual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interference effects from divided attention during retrieval in younger and older adults.

The authors examined how retrieval, under divided attention (DA) conditions, is affected by the type of material in a concurrent task, and whether aging produces larger interference effects on memory. Young and old adults studied a list of unrelated words under full attention, and recalled them while performing either an animacy decision task to words or an odd-digit identification task to numbers. The animacy-distracting task interfered substantially with retrieval, and the size of the effect was not amplified in older compared with younger adults. DA using the odd-digit task did not produce as large an interference effect. These findings support the component-process model of memory, and pose problems for resource models of interference from DA at retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Latent inhibition in human adults without masking.

Latent inhibition refers to attenuated responding to Cue X observed when the X-outcome pairings are preceded by X-alone presentations. It has proven difficult to obtain in human adults unless the preexposure (X-alone) presentations are embedded within a masking (i.e., distracting) task. The authors hypothesized that the difficulty in obtaining latent inhibition with unmasked tasks is related to the usual training procedures, in which the preexposure and conditioning experiences are separated by a set of instructions. Experiment 1 reports latent inhibition without masking in a task in which preexposure and conditioning occur without interruption. Experiments 2 and 3 demonstrate that this attenuation in responding to target Cue X does not pass a summation test for conditioned inhibition and is context specific, thereby confirming that it is latent inhibition. Experiments 3 and 4 confirm that introducing instructions between preexposure and conditioning disrupts latent inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial attention and response control in healthy younger and older adults and individuals with Alzheimer's disease: Evidence for disproportionate selection impairments in the simon task.

The authors examined the degree to which aging and Alzheimer's disease (AD) influence the ability to control attention when conflict is presented in terms of incongruent mapping between a stimulus and the appropriate response. In a variant of the Simon task, healthy older adults and older adults with mild or very mild AD showed disproportionately larger reaction time (RT) costs when the stimulus and response were in conflict relative to RT costs of healthy younger adults. Analyses of RT distributions provide support for a 2-process model of the Simon effect in which there is a short-lived transient effect of the irrelevant dimension in younger adults and a more sustained influence across the RT distribution in older adults. An analysis of error rates showed that the older adults with mild and very mild AD made more errors on incongruent trials, suggesting that AD leads to increased likelihood of selecting the prepotent pathway. The findings are discussed in terms of the special nature of the response requirements of the Simon task to better illuminate the attentional decrements in both healthy aging and early stage AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional asymmetry in schizophrenia: Disengagement and inhibition of return deficits.

This research examined 2 components of visual orienting in medicated schizophrenia patients: the validity effect and the inhibition of return (IOR). In the 1st experiment, patients showed the expected asymmetry in orienting attention, that is, larger validity effect in the right visual field than in the left. However, this asymmetry was due to a deficit in facilitatory processes rather than a disengagement deficit. In addition, patients showed a deficit in IOR. In the 2nd experiment, a 2nd central cue for summoning attention, explicitly, back to the center was used. In this experiment, normal IOR in schizophrenia patients was found. Because it was shown that schizophrenia patients do not have a disengagement deficit, IOR possibly could not be observed because of the increased facilitation in that location. It was proposed that the abnormality in visual attention in schizophrenia is due to a deficit in inhibitory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neural basis for recognition confidence in younger and older adults.

Although several studies have examined the neural basis for age-related changes in objective memory performance, less is known about how the process of memory monitoring changes with aging. The authors used functional magnetic resonance imaging to examine retrospective confidence in memory performance in aging. During low confidence, both younger and older adults showed behavioral evidence that they were guessing during recognition and that they were aware they were guessing when making confidence judgments. Similarly, both younger and older adults showed increased neural activity during low- compared to high-confidence responses in the lateral prefrontal cortex, anterior cingulate cortex, and left intraparietal sulcus. In contrast, older adults showed more high-confidence errors than younger adults. Younger adults showed greater activity for high compared to low confidence in medial temporal lobe structures, but older adults did not show this pattern. Taken together, these findings may suggest that impairments in the confidence–accuracy relationship for memory in older adults, which are often driven by high-confidence errors, may be primarily related to altered neural signals associated with greater activity for high-confidence responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monitoring one's own forgetting in younger and older adults.

The present study examined whether there are age-related differences in the ability to accurately monitor forgetting. Young and older adults studied a mixed list of categorized words, and later recalled items when cued with each category. They then estimated the number of additional items that they did not recall—a form of monitoring one's forgetting. Older adults exhibited impaired memory performance compared with young adults, but also accurately estimated they forgot more information than young adults. Both age groups were fairly accurate in predicting forgetting in terms of resolution, indicating that aging does not impair the ability to monitor forgetting. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Adaptation to visuomotor rotations in younger and older adults.

Adaptation to a visuomotor rotation is known to be impaired at older adult age. The authors examined whether the impairment is present already at preretirement age and whether it depends on the difficulty of the adaptation task. Moreover, the authors tested predictions of the hypothesis that the age-related impairment pertains primarily to strategic corrections and the explicit knowledge on which they are based but not to the acquisition of an (implicit) internal model of the novel visuomotor transformation. The authors found an age-related impairment of adaptation and explicit knowledge already at preretirement age but no age-related change of aftereffects. With an incremental simplification of the adaptation task, age-related changes were able to be eliminated. Individual differences of the quality of explicit knowledge were associated with differences of adaptation, but not of aftereffects. When age groups were matched by explicit knowledge, age-related impairments of adaptation largely disappeared. However, a reliable difference remained in one of the experiments, suggesting that other processes of adjustment to a visuomotor rotation might be affected by aging as well. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional complexity in younger, midlife, and older adults.

Questions pertaining to emotional complexity in adult development are being pursued from a number of vantage points. The current studies sought to clarify the study of emotional complexity by comparing and contrasting 2 dominant perspectives on emotional complexity in different age groups (i.e., covariation and absolute-level approaches). Results indicate that emotional complexity is a multifaceted construct and that methodology will impact substantive findings and developmental trends that emerge from the data. Recommendations and considerations for future research are discussed, including, for example, within- versus cross-domain ideas of emotional complexity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eliminating inhibition of return by changing salient nonspatial attributes in a complex environment.

Inhibition of return (IOR) occurs when a target is preceded by an irrelevant stimulus (cue) at the same location: Target detection is slowed, relative to uncued locations. In the present study, we used relatively complex displays to examine the effect of repetition of nonspatial attributes. For both color and shape, attribute repetition produced a robust inhibitory effect that followed a time course similar to that for location-based IOR. However, the effect only occurred when the target shared both the feature (i.e., color or shape) and location with the cue; this constraint implicates a primary role for location. The data are consistent with the idea that the system integrates consecutive stimuli into a single object file when attributes repeat, hindering detection of the second stimulus. The results are also consistent with an interpretation of IOR as a form of habituation, with greater habituation occurring with increasing featural overlap of a repeated stimulus. Critically, both of these interpretations bring the IOR effect within more general approaches to attention and perception, rather than requiring a specialized process with a limited function. In this view, there is no process specifically designed to inhibit return, suggesting that IOR may be the wrong framing of inhibitory repetition effects. Instead, we suggest that repetition of stimulus properties can interfere with the ability to focus attention on the aspects of a complex display that are needed to detect the occurrence of the target stimulus; this is a failure of activation, not an inhibition of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional momentum does not underlie the inhibition of return effect.

J. Pratt, T. M. Spalek, and F. Bradshaw (1999) recently proposed that attentional momentum is the mechanism underlying the inhibition of return (IOR) effect. They suggested that momentum associated with an attentional movement away from a peripherally cued location and toward an uncued opposite location is essential and fundamental to the finding of an IOR effect. Although it is clear from the present study and from a reanalysis of data from Pratt et al. that response time can be facilitated at an uncued opposite location, this putative effect of attentional momentum is neither robust nor reliable. First, it occurs for only a minority of participants. Second, it occurs in only a subset of the cued display positions. And finally, it is uncorrelated with the occurrence of IOR. Together the data indicate that the attentional momentum hypothesis is an overgeneralization and that it does not underlie the robust and reliable IOR effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)