Perspectives of Interactions with Healthcare Providers Among Patients Who Are Blind.

Healthcare providers' (HCPs) stereotypes about the incompetence of blind and low-vision patients may lead them to patronize blind patients, over-focus on impairments, and neglect the presenting problem. The content of perceived HCP stereotypes about blind patients in the clinical setting was examined from the patient perspective with seven focus groups, including a total of 42 individual participants. Most participants reported an interaction when their HCPs treated them as if they were incompetent, and discussed how perceived evaluations of their warmth and competence impacted whether their HCPs trusted and respected them. Participants also discussed their evaluations of their HCPs' warmth and competence, and how these evaluations impacted their trust and respect for the HCP. These results provide insight into blind patients' experiences interacting with their HCPs and can inform interventions to 1) help HCPs avoid stereotypic attitudes and 2) improve HCPs' comfort and abilities when working with patient with disabilities.

Crossing event boundaries changes prospective perceptions of temporal length and proximity.

We conducted two experiments to investigate how crossing a single naturalistic event boundary impacted two different types of temporal estimation involving the same target duration - one where participants directly compared marked temporal durations and another where they judged the temporal proximity of stimuli. In Experiment 1, participants judged whether time intervals presented during movies of everyday events were shorter or longer than a previously encoded 5-s reference interval. We examined how the presence of a transition between events (event boundary) in the movie influenced people's judgments about the length of the comparison interval. Comparison intervals presented during a portion of the movie containing an event boundary were judged as shorter than the reference interval more often than comparison intervals that contained no boundary. Working-memory updating at the event boundary may have directed attention away from the concurrent timing task. In Experiment 2, participants judged whether the second of three tones presented during everyday movies was closer to the first or the third tone presented. Tones separated by an event boundary were judged as farther apart than tones contained within the same event. When judging temporal proximity, attention directed to processing information at an event boundary between two stimuli may disrupt the formation of temporal associations between those stimuli. Overall, these results demonstrate that crossing a single event boundary can impact people's prospective perceptions of the temporal characteristics of their experience and suggest that the episodic memory updating that occurs during an event boundary both captures timing-relevant attentional resources and plays a role in the temporal binding of information.

The influence of everyday events on prospective timing "in the moment".

We conducted two experiments to investigate how the eventfulness of everyday experiences influences people's prospective timing ability. Specifically, we investigated whether events contained within movies of everyday activities serve as markers of time, as predicted by Event Segmentation Theory, or whether events pull attention away from the primary timing task, as predicted by the Attentional Gate theory. In the two experiments reported here, we asked participants to reproduce a previously learned 30-s target duration while watching a movie that contained eventful and uneventful intervals. In Experiment 2, reproduction also occurred during "blank movies" while watching a fixation. In both experiments, participants made shorter and more variable reproductions while simultaneously watching eventful as compared to uneventful movie intervals. Moreover, in Experiment 2, the longest reproductions were produced when participants had to watch the blank movies, which contained no events. These results support Event Segmentation Theory and demonstrate that the elapsing events during prospective temporal reproduction appear to serve as markers of temporal duration rather than distracting from the timing task.

Recall and response time norms for English-Swahili word pairs and facts about Kenya.

In the vast literature exploring learning, many studies have used paired-associate stimuli, despite the fact that real-world learning involves many different types of information. One of the most popular materials used in studies of learning has been a set of Swahili-English word pairs for which Nelson and Dunlosky (Memory 2; 325-335, 1994) published recall norms two decades ago. These norms involved use of the Swahili words as cues to facilitate recall of the English translation. It is unclear whether cueing in the opposite direction (from English to Swahili) would lead to symmetric recall performance. Bilingual research has suggested that translation in these two different directions involves asymmetric links that may differentially impact recall performance, depending on which language is used as the cue (Kroll & Stewart, Journal of Memory and Language 33; 149-174,1994). Moreover, the norms for these and many other learning stimuli have typically been gathered from college students. In the present study, we report recall accuracy and response time norms for Swahili words when they are cued by their English translations. We also report norms for a companion set of fact stimuli that may be used along with the Swahili-English word pairs to assess learning on a broader scale across different stimulus materials. Data were collected using Amazon's Mechanical Turk to establish a sample that was diverse in both age and ethnicity. These different, but related, stimulus sets will be applicable to studies of learning, metacognition, and memory in diverse samples.

Physical activity is related to timing performance in older adults.

Physical activity has been linked to better cognitive function in older adults, especially for executive control processes. Researchers have suggested that temporal processing of durations less than 1 second is automatic and engages motor processes, while timing of longer durations engages executive processes. The purpose of this study was to determine whether a higher level of physical activity is associated with better reproduction performance in older adults, especially for durations in the "cognitive" range (i.e., longer than 1 s). Older right-handed adults completed a temporal reproduction task with five target durations (300, 650, 1000, 1350, and 1700 ms). Physical activity level was assessed via estimation of VO2 peak using a self-report activity scale. Results indicated that higher physical activity level was associated with better timing accuracy and that this effect was dependent on target duration. Namely, the relationship between physical activity and timing accuracy was strongest at the longest durations. Therefore, greater physical activity in older adults may have specific benefits linked to better executive functions.

Keep up the pace: declines in simple repetitive timing differentiate healthy aging from the earliest stages of Alzheimer's disease.

The current study examined whether healthy older adults (OA) and individuals at the earliest stages of dementia of the Alzheimer's type (DAT) differ from younger adults (YA) and from each other on a simple, extended continuous tapping task using intervals (500 ms, 1000 ms, and 1500 ms) thought to differentially engage attentional control systems. OA groups sped up their tapping at the slowest target rate compared to the YA; this pattern was magnified in the early stage DAT groups. Performance variability appeared especially sensitive to DAT-related changes, as reliable differences between healthy OA and very mild DAT individuals emerged for multiple tap rates. These differences are proposed to result from breakdowns in attentional control that disrupt error-correction processes and the ability to resolve discrepancies between internally-generated temporal expectancies and the external temporal demands of the repetitive timing task.

Reaching for words and nonwords: interactive effects of word frequency and stimulus quality on the characteristics of reaching movements.

Word frequency and stimulus degradation produce large and additive effects in the onset latencies of lexical decision responses. The influence of these two variables was examined in a lexical decision task where continuous arm-reaching responses were required and movement trajectories were tracked. The results yielded the typical additive pattern of word frequency and stimulus degradation on reaction time and movement duration. Importantly, however, an examination of movement trajectories revealed interactive effects of word frequency and stimulus degradation that emerged for the early part of the movement. These findings suggest that factors thought to influence early stages of stimulus identification continue to influence the dynamics of the response after response initiation, motivating a need to reevaluate current models of lexical decision performance. Moreover, this work highlights how the dynamics of naturalistic multidimensional responses provide a richer source of information about decision-making processes than do discrete unidimensional measures.

Differential callosal contributions to bimanual control in young and older adults.

Our recent work has shown that older adults are disproportionately impaired at bimanual tasks when the two hands are moving out of phase with each other [Bangert, A. S., Reuter-Lorenz, P. A., Walsh, C. M., Schachter, A. B., & Seidler, R. D. Bimanual coordination and aging: Neurobehavioral implications. Neuropsychologia, 48, 1165-1170, 2010]. Interhemispheric interactions play a key role during such bimanual movements to prevent interference from the opposite hemisphere. Declines in corpus callosum (CC) size and microstructure with advancing age have been well documented, but their contributions to age deficits in bimanual function have not been identified. In the current study, we used structural magnetic resonance and diffusion tensor imaging to investigate age-related changes in the relationships between callosal macrostructure, microstructure, and motor performance on tapping tasks requiring differing degrees of interhemispheric interaction. We found that older adults demonstrated disproportionately poorer performance on out-of-phase bimanual control, replicating our previous results. In addition, older adults had smaller anterior CC size and poorer white matter integrity in the callosal midbody than their younger counterparts. Surprisingly, larger CC size and better integrity of callosal microstructure in regions connecting sensorimotor cortices were associated with poorer motor performance on tasks requiring high levels of interhemispheric interaction in young adults. Conversely, in older adults, better performance on these tasks was associated with larger size and better CC microstructure integrity within the same callosal regions. These findings implicate age-related declines in callosal size and integrity as a key contributor to bimanual control deficits. Further, the differential age-related involvement of transcallosal pathways reported here raises new questions about the role of the CC in bimanual control.

Dissecting the clock: understanding the mechanisms of timing across tasks and temporal intervals.

Currently, it is unclear what model of timing best describes temporal processing across millisecond and second timescales in tasks with different response requirements. In the present set of experiments, we assessed whether the popular dedicated scalar model of timing accounts for performance across a restricted timescale surrounding the 1-second duration for different tasks. The first two experiments evaluate whether temporal variability scales proportionally with the timed duration within temporal reproduction. The third experiment compares timing across millisecond and second timescales using temporal reproduction and discrimination tasks designed with parallel structures. The data exhibit violations of the assumptions of a single scalar timekeeper across millisecond and second timescales within temporal reproduction; these violations are less apparent for temporal discrimination. The finding of differences across tasks suggests that task demands influence the mechanisms that are engaged for keeping time.

Bimanual coordination and aging: neurobehavioral implications.

We investigate whether aging leads to global declines in discrete and continuous bimanual coordination tasks thought to rely on different control mechanisms for temporal coupling of the limbs. All conditions of continuous bimanual circle drawing were associated with age-equivalent temporal control. This was also true for discrete simultaneous tapping. Older adults' between-hand coordination deficits were specific to discrete tapping conditions requiring asynchronous intermanual timing and were associated with self-reported executive dysfunction on the Dysexecutive (DEX) questionnaire. Also, older adults exclusively showed a relationship between the most difficult bimanual circling condition and a measure of working memory. Thus, age-related changes in bimanual coordination are specific to task conditions that place complex timing demands on left and right hand movements and are, therefore, likely to require executive control.

The prehistory of discovery: precursors of representational change in solving gear system problems.

Microgenetic research has identified 2 different types of processes that produce representational change: theory revision and redescription. Both processes have been implicated as important sources of developmental change, but their relative status across development has not been addressed. The current study investigated whether (a) the process of representational change undergoes developmental change itself or (b) different processes occupy different niches in the course of knowledge acquisition. College, 3rd-, and 6th-grade students solved gear system problems over 2 sessions. For all grades, discovery of the physical principles of the gear system was consistent with theory revision, but discovery of a more sophisticated strategy, based on the alternating sequence of gears, was consistent with redescription. The results suggest that these processes may occupy different niches in the course of acquiring knowledge and that the processes are developmentally invariant across a broad age range.