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A task is ideomotor (IM)-compatible when there is high conceptual similarity between the stimulus and the associated response (e.g., pressing a left key when an arrow points to the left). For such an easy task, can response selection operate automatically, bypassing the attentional bottleneck that normally constrains dual-task performance? To address this question, we manipulated the IM compatibility of a Task 2 that was performed concurrently with a non-IM-compatible Task 1, using the psychological refractory period procedure. Single-task trials, randomly intermixed with dual-task trials, served as a baseline against which to assess dual-task costs. The results indicated bottleneck bypassing (i.e., simultaneous response selection on both tasks) when Task 2 was IM-compatible, as evidenced by negligible dual-task costs on Task 2 (as well as on Task 1), very high percentages of response reversals, and weak correlations between Task-1 and Task-2 reaction times. These findings were supported by a fine-grained simulation analysis of inter-response intervals. We conclude that the perception of an IM-compatible stimulus directly activates the response code, which can then be selecting automatically, without recruiting central attention, consistent with A. G. Greenwald's (Journal of Experimental Psychology, 94, 52-57, 1972) original theory of IM compatibility.

To estimate the time-to-contact (TTC) of a moving object, numerous studies have focused on the type of information or gaze strategy used by the observer. However, it remains to be determined whether and how attention could affect TTC estimation. In particular, how does TTC estimation operate when less attention is available? To answer this question, we conducted two experiments in which the participants had to perform an absolute (Experiment 1) or relative (Experiment 2) prediction-motion task, either alone (i.e., in single-task condition) or along with a secondary, visual working-memory task (i.e., in dual-task condition). In both experiments, we found that TTC estimation was superior in dual-task condition relative to single-task condition. This finding suggests that the reduction of available attention actually improves TTC estimation. We discuss possible explanations as well as theoretical implications for this seemingly counter-intuitive finding. Further research is needed to investigate if (in)attention facilitates or only shifts TTC estimation.

Drivers face frequent distraction on the roadways, but little is known about situations placing them at risk of misallocating visual attention. To investigate this issue, we asked participants to search for a red target embedded within simulated driving scenes (photographs taken from inside a car) in three experiments. Distraction was induced by presenting, via a GPS unit, red or green distractors positioned in an irrelevant location at which the target never appeared. If the salient distractor captures attention, visual search should be slower on distractor-present trials than distractor-absent trials. In Experiment 1, salient distractors yielded no such capture effect. In Experiment 2, we decreased the frequency of the salient distractor from 50% of trials to only 10% or 20% of trials. Capture effects were almost five times larger for the 10% occurrence group than for the 20% occurrence group. In Experiment 3, the amount of available central resources was manipulated by asking participants to either simultaneously monitor or ignore a stream of spoken digits. Capture effects were much larger for the dual-task group than for the single-task group. In summary, these findings identify risk factors for attentional capture in real-world driving scenes: distractor rarity and diversion of attention., (© 2016 The British Psychological Society.)

Does practice reduce, or even eliminate, aging effects on the attentional limitations responsible for dual-task interference? The studies reviewed in this article show that age differences reliably persist after extensive practice. Strikingly, dual-task interference remains larger among older adults even in training conditions that allow them to achieve single-task performance as fast as younger adults. These findings demonstrate that age deficits in attentional functioning are robust. Advancing age also can be accompanied by improvements in cognitive functioning, such as in the ability to access the lexicon without attention (i.e., automatically), due to lifelong experience with word reading. Future research needs to establish whether age deficits in central attention are due to structural changes that are irreversible or reversible to some extent.

Do sexual words have high attentional priority? How does the ability to ignore sexual distractors evolve with age? To answer these questions, two experiments using Rapid Serial Visual Presentation (RSVP) were conducted. Experiment 1 showed that both younger and older participants were better at identifying a target (the name of a colour) when it was preceded by 336 ms by a sexual word rather than by a musical word. Strikingly, the sexual-word advantage was more pronounced for older adults than for younger adults. Experiment 2 showed that introducing a variable delay between the distractor and the target eliminated the sexual-word advantage. This finding suggests that the sexual-word advantage found in Experiment 1 was due to learning to utilize the sexual word as a temporal cue with a fixed duration between the distractor and the target. Contrary to previous research [Arnell et al., 2007, Emotion, 7, 465), neither experiment showed that sexual words produce an attentional blink., (© 2013 The British Psychological Society.)

Can elderly adults automatize a new task? To address this question, 10 older adults each performed 10,080 training trials over 12 sessions on an easy but novel task. The psychological refractory period (PRP) procedure was then used to evaluate whether this highly practiced task, when presented as task 2 along with an unpracticed task 1, could proceed automatically. If automatic, task 2 processing should bypass the bottleneck and, therefore, not be delayed while central attention is devoted to task 1, yielding little dual-task interference. This is exactly what Maquestiaux, Laguë-Beauvais, Ruthruff, and Bherer (Memory and Cognition 36:1262-1282, 2008) previously observed for almost all younger adults, even with half the training on a more difficult task. Although extensive training reduced older adults' reaction times to only 307 ms, a value virtually identical to that attained by Maquestiaux et al.'s (Memory and Cognition 36:1262-1282, 2008) younger adults, the highly practiced task 2 was slowed by 485 ms in the dual-task PRP procedure. Such a large slowing in older adults is striking given the easy tasks and massive amounts of practice. These findings demonstrate a qualitative change with age, in which older adults lose the ability to automatize novel tasks, which cannot be attributed merely to generalized cognitive slowing.

This study assessed the relationship between cardiovascular fitness and temporal preparation in elderly persons. 110 older adults (aged 60-69 or 70-79 years) were sorted into low- and high-fit groups based on aerobic fitness level estimated with a walking test. Response preparation processes were assessed with reaction time tasks in which short (1, 3, 5 s) and long (5, 7, 9 s) preparatory intervals varied randomly. The results suggest a better ability in high-fit individuals to maintain preparation over time (up to 9 s). Results of the present study suggest that in older adults, a high level of aerobic fitness is associated with more efficient response preparation processes.

Does advancing age reduce the ability to bypass the central bottleneck through task automatization? To answer this question, the authors asked 12 older adults and 20 young adults to first learn to perform an auditory-vocal task (low vs. high pitch) in 6 single-task sessions. Their dual-task performance was then assessed with a psychological refractory period paradigm, in which the highly practiced auditory-vocal task was presented as Task 2, along with an unpracticed visual-manual Task 1. Converging evidence indicated qualitative differences in dual-task performance with age: Whereas the vast majority of young adults bypassed the bottleneck, at most 1 of the 12 older adults was able to do so. Older adults are either reluctant to bypass the bottleneck (as a matter of strategy) or have lost the ability to automatize task performance.

In this research, the controversial issue of whether the central bottleneck can be bypassed through task automatization was investigated. To examine this issue, participants received six single-task practice sessions with an auditory-vocal task (low vs. high pitch). We then assessed dual-task performance using the analytically tractable psychological refractory period (PRP) paradigm, in which the highly practiced auditory-vocal task was presented as Task 2, along with an unpracticed visual-manual Task 1. The results provide evidence of bottleneck bypass for virtually all the participants (17 out of 20). Several converging tests suggest that the bottleneck reemerged, however, in a follow-up experiment with tasks presented in the opposite order (auditory-vocal Task 1 and visual-manual Task 2). One possible explanation is that tasks greedily recruit central resources when available, even though they can operate without central resources when unavailable.

Dual-task processing was explored in younger and older adults in 2 experiments that used a tone discrimination and a letter discrimination task. To encourage parallel processing if that was possible, the authors presented the stimuli for the 2 tasks simultaneously, and participants were instructed to withhold their responses until both were ready. The authors found no evidence for parallel processing and no evidence that the management of central processing of dual tasks is qualitatively different in older adults than it is in younger adults. When one response was verbal and the other manual, the 2 responses closely coincided. When both responses were manual, the authors did find that the first response was not delayed enough to coincide with the 2nd and that this underestimation was greater in older adults., (((c) 2007 APA, all rights reserved).)

Can dual-task practice remove age-related differences in the psychological refractory period (PRP) effect? To answer this question, younger and older individuals practiced 7 blocks of a PRP design, in which Task 1 (T1) required a vocal response to an auditory stimulus and Task 2 (T2) required a manual response to a visual stimulus (Experiment 1). The results showed that practice did not reduce, but rather increased, age-related differences in PRP interference. Using the trained individuals, the introduction of a less complex new T1 (Experiment 2) or a less complex new T2 (Experiment 3) with the task previously practiced reduced the PRP interference but only in older adults. The authors propose that older adults suffer from a large task-switch cost that is more sensitive to task complexity than to the amount of practice., (copyright (c) 2004 APA, all rights reserved.)

Can people perform two novel tasks in parallel? Available evidence and prevailing theories overwhelmingly indicate that the answer is no, due to stubborn capacity limitations in central stages (e.g., a central bottleneck). Here we propose a new hypothesis, which suggests otherwise: people are capable of fully parallel central processing (i.e., bypassing the central bottleneck), yet often fail to do so, mainly due to preparation neglect. This preparation-neglect hypothesis was evaluated in four dual-task experiments pairing novel tasks (Task 1 and Task 2) using arbitrary stimulus–response mappings. Experiment 1, using a classic psychological refractory period (PRP) procedure, replicated the finding of dozens of previous PRP studies: none of the participants bypassed the bottleneck, instead exhibiting large dual-task interference on Task 2 (445 ms). In Experiment 2, the same dual-task PRP trials were randomly intermixed with single-task trials on Task 2, to boost preparation on that task. Here, nearly half the sample of participants bypassed the central bottleneck, exhibiting small dual-task interference on Task 2 (48 ms). Two additional experiments showed that initial practice does not by itself enable bottleneck bypassing, but boosting preparation of Task 2 (via intermixing single-task trials of Task 2) does. We conclude that, when properly prepared, people are capable of far more dual-task automaticity than was previously believed. Public Significance Statement: This study examined the source of the processing limitations that people generally encounter when attempting to perform two tasks at the same time. We demonstrated that novel tasks, when properly prepared, can be performed entirely automatically (i.e., without recruiting attentional resources), thereby bypassing the processing limitations. This finding of dual-task automaticity is striking given that the tasks were neither particularly easy nor previously trained. The key enabler of dual-task automaticity was not practice but boosting advanced preparation of the to-be-performed tasks. [ABSTRACT FROM AUTHOR]

This commentary explores the relationships between the construct of successful aging and the experimental psychology of human aging- cognitive gerontology. What can or should cognitive gerontology contribute to understanding, defining, and assessing successful aging? Standards for successful aging reflect value judgments that are culturally and historically situated. Fundamentally, they address social policy; they are prescriptive. If individuals or groups are deemed to be aging successfully, then their characteristics or situations can be emulated. If an individual or a group is deemed to be aging unsuccessfully, then intervention should be considered. Although science is never culture-free or ahistorical, cognitive gerontology is primarily descriptive of age-related change. It is not prescriptive. It is argue that cognitive gerontology has little to contribute to setting standards for successful aging. If, however, better cognitive function is taken as a marker of more successful aging- something not universally accepted-then cognitive gerontology can play an important assessment role. It has a great deal to contribute in determining whether an individual or a group evidences better cognitive function than another. More importantly, cognitive gerontology can provide tools to evaluate the effects of interventions. It can provide targeted measures of perception, attention, memory, executive function, and other facets of cognition that are more sensitive to change than most clinical measures. From a deep understanding of factors affecting cognitive function, cognitive gerontology can also suggest possible interventions. A brief narrative review of interventions that have and have not led to improved cognitive function in older adults. Finally, the enormous range is addressed in the estimates of the proportion of the population that meets a standard for aging successfully, from less than 10% to more than 90%. For research purposes, it would be better to replace absolute cutoffs with correlational approaches (e.g., Freund & Baltes, 1998, Psychology and Aging, 13, 531-543). For policy purposes, cutoffs are necessary, but we propose that assessments of successful aging be based not on absolute cutoffs but on population proportions. An example of one possible standard is this: Those more than 1 standard deviation above the mean are aging successfully; those more than 1 standard deviation below the mean are aging unsuccessfully; those in between are aging usually. Adoption of such a standard may reduce the wide discrepancies in the incidence of successful aging reported in the literature. [ABSTRACT FROM AUTHOR]

Can motor learning be equivalent in younger and older adults? To address this question, 48 younger (M = 23.5 years) and 48 older (M = 65.0 years) participants learned to perform a golf-putting task in two different motor learning situations: one that resulted in infrequent errors or one that resulted in frequent errors. The results demonstrated that infrequent-error learning predominantly relied on nondeclarative, automatic memory processes whereas frequent-error learning predominantly relied on declarative, effortful memory processes: After learning, infrequent-error learners verbalized fewer strategies than frequent-error learners; at transfer, a concurrent, attention-demanding secondary task (tone counting) left motor performance of infrequent-error learners unaffected but impaired that of frequent-error learners. The results showed age-equivalent motor performance in infrequent-error learning but age deficits in frequent-error learning. Motor performance of frequent-error learners required more attention with age, as evidenced by an age deficit on the attention-demanding secondary task. The disappearance of age effects when nondeclarative, automatic memory processes predominated suggests that these processes are preserved with age and are available even early in motor learning. [ABSTRACT FROM PUBLISHER]