Secondary task engagement and disengagement in the context of highly automated driving

During highly automated driving (level 3 automation according to SAE International, 2014) people are likely to increase the frequency of secondary task interactions. However, the driver must still be able to take over control within a reasonable amount of time. Previous studies mainly investigated take-over behavior by forcing participants to engage in secondary tasks prior to take over, and barely addressed how drivers voluntarily schedule secondary task processing according to the availability and predictability of automated driving modes. In the current simulator study 20 participants completed a test drive with alternating sections of manual and highly automated driving. One group had a preview on the availability of the automated driving system in upcoming sections of the track (predictive HMI), while the other drivers served as a control group. A texting task was offered during both driving modes and also prior to take-over situations. Participants were free to accept or reject a given task, taking the situational demands into account. Drivers accepted more tasks during highly automated driving. Furthermore, tasks were rejected more often prior to take-over situations in the predictive HMI group. This was accompanied by safer take-over performance. However, once engaged in a task, drivers tended to continue texting even in take-over situations. The results indicate the need to discriminate different aspects of task handling regarding self-regulation: task engagement and disengagement.     

The life tasks model: Enhancing psychological and spiritual growth in the aged

ABSTRACT

The life tasks model is an active, mutual, and potentially universal approach to the spiritual care of the aged. A life task is a responsibility, once undertaken, that lasts a lifetime. Three tasks are identified. Task 1 is the discovery of hidden learning. The process of discovery draws on implicit learning that comes into awareness. This leads to task 2, testing in which learning brought into awareness is tested by other life experiences. The final task is task 3, integration, in which a more aware and cohesive self is formed. Ideally, this leads to service or vocation. Progress on the life tasks is illustrated by responses in a qualitative study of older adults. Although this model can be applied to self-growth and ministry to all ages, it is well suited to the care of the aged.     

Task-defined associations are mode specific for selection of relevant dimension but mode independent for selection of location mapping

When compatible and incompatible mappings of a location-relevant task are mixed, or a location-relevant task is mixed with a task for which stimulus location is irrelevant, the benefit of the compatible mapping is eliminated for physical locations and enhanced for location words. Two experiments examined the influence of presenting the location information for the mixed conditions in different stimulus modes (physical location or word). Experiment 1 showed that the effects of mixing location-relevant and location-irrelevant tasks on the spatial compatibility and Simon effects are reduced when the location information is presented in different modes for the two tasks. Experiment 2 showed, in contrast, that the mode distinction had little influence on the effects of mixed compatible and incompatible mappings for location-relevant tasks: The compatibility effect was eliminated for physical locations and enhanced for words, as when there is no mode distinction. Thus, when location is relevant for one task and colour for the other, the task-defined associations of locations to responses are mode specific, but when location is relevant for both tasks, the associations are mode independent.     

Combining speed and accuracy to assess error-free cognitive processes

Both the speed and accuracy of responding are important measures of performance. A well-known interpretive difficulty is that participants may differ in their strategy, trading speed for accuracy, with no change in underlying competence. Another difficulty arises when participants respond slowly and inaccurately (rather than quickly but inaccurately), e.g., due to a lapse of attention. We introduce an approach that combines response time and accuracy information and addresses both situations. The modeling framework assumes two latent competing processes. The first, the error-free process, always produces correct responses. The second, the guessing process, results in all observed errors and some of the correct responses (but does so via non-specific processes, e.g., guessing in compliance with instructions to respond on each trial). Inferential summaries of the speed of the error-free process provide a principled assessment of cognitive performance reducing the influences of both fast and slow guesses. Likelihood analysis is discussed for the basic model and extensions. The approach is applied to a data set on response times in a working memory test. The authors wish to thank Roger Ratcliff, Christopher Chabris, and three anonymous referees for their helpful comments, and Aureliu Lavric for providing the data analyzed in this paper.     

Enactment enhances integration between verb and noun, but not relational processing, in episodic memory

Improved recall has consistently been demonstrated following motor activation at encoding (SPT), compared to traditional verbal learning (VT). Enhancements of item-specific processing and relational processing have been proposed as possible mechanisms to account for this SPT effect. There is ample evidence supporting the notion of enhanced item-specific processing, however it is still unclear whether enhancement of relational processing contributes to improved recall. In the present study, 2 experiments were designed to address this issue. In Experiment 1, memory under 2 encoding conditions (VT vs. SPT) and 3 recall conditions (free recall vs. category-cued recall vs. verb-cued recall) were studied in 3 large samples (N= 500-600). Experiment 2 replicated the findings of Experiment 1, and controlled for the use of actual objects, short-term memory effects, and carryover effects, in Experiment 1. The results in both experiments showed an interaction between type of encoding and type of recall. Verb-cued recall was affected differently by SPT encoding, as compared to category-cued recall and free recall. The results indicate that enhanced integration between verb and noun is an effect of SPT encoding, whereas enhanced relational processing is not.     

A Comparison of Least-to-Most Prompts and Progressive Time Delay on the Disruptive Behavior of Students with Autism

We compared the effects of two instructional strategies on the frequency of errors and episodes of disruptive behavior of 4 students with autism. In Phase I, easy and difficult tasks were presented to determine whether the tasks were associated with differential rates of disruptive behavior. Phase II compared the effects of a least-to-most prompting procedure (LTM) to a progressive time delay procedure (PTD) on errors and disruptive behavior when difficult tasks were presented. Observers sequentially recorded instructor instructions, response prompts, prompts for appropriate sitting, and feedback statements; and student disruptive, correct, error, and no responses during 1:1 sessions. Results showed PTD produced fewer errors than LTM for all 4 students, and lower rates of disruptive behavior for 2 students. When PTD was implemented as the final phase with 2 of the students, rates of disruptive behavior associated with the task previously taught with LTM immediately decreased. Conditional probability statements indicated that disruptive behavior occurred infrequently with all 4 students when effective response prompts were used.     

An elicitation method for multiple linear regression models

This paper describes a method of quantifying subjective opinion about a normal linear regression model. Opinion about the regression coefficients and experimental error is elicited and modeled by a multivariate probability distribution (a Bayesian conjugate prior distribution). The distribution model is richly parameterized and various assessment tasks are used to estimate its parameters. These tasks include the revision of opinion in the light of hypothetical data, the assessment of credible intervals, and a task commonly performed in cue-weighting experiments. A new assessment task is also introduced. In addition, implementation of the method in an interactive computer program is described and the method is illustrated with a practical example.     

Evaluating backward chaining methods on vocational tasks by adults with developmental disabilities

Backward chains are widely used to teach complex skills to individuals with developmental disabilities. Implementation of chaining procedures may vary regarding untaught steps and there is little to guide practitioners in the selection of chaining procedures. Moreover, there is a dearth of research evaluating effectiveness and efficiency of procedural variations of behavior chains. The purpose of this study was to extend previous research by evaluating the effectiveness, efficiency, and preference for four procedural variations (i.e., teacher‐completion, participant‐completion, no‐completion, and a control condition) of backward chains across vocational tasks with adults with developmental disabilities. Although procedural variations effectively established vocational skills, the participant‐completion procedure (in which the instructor implemented a least‐to‐most prompt hierarchy during all untrained steps in the chain) was the most efficacious backward chaining procedural variation and efficient in terms of sessions to mastery. The no‐completion procedure (in which the instructor completed all untrained steps in the chain out of view of the participant) was least efficient across trials, sessions, errors, and total duration to mastery. One participant preferred the no‐completion condition while the other two participants showed an initial preference for the teacher‐completion condition that changed to preference for the no‐completion condition. Vocational skills maintained 1‐ and 4‐weeks postmastery. Stakeholders rated goals, procedures, and outcomes as socially valid.     

Tactile detection response task: Metrics for assessing drivers’ cognitive workload

The Tactile Detection Response Task (TDRT) has been used to assess the cognitive workload of driver distraction with response time and miss rate as metrics of cognitive workload. However, it is not clear which metric is more sensitive and whether sensitivity is maintained for visual tasks. The objective of this study was to assess the sensitivity of the TDRT to changes in cognitive workload and to examine whether the sensitivity depends on task modality. A driving simulator study was conducted with 24 participants. The study included restaurant selection tasks with three presentation modalities (auditory, visual, and hybrid) and two difficulty levels (low and high). The high difficulty level was designed to be more cognitively demanding than the low difficulty level. Mixed-effects models were applied to examine the TDRT metrics and task difficulty level. The model controlled for age group, gender, and included a random effect for participants. The high difficulty level of the auditory tasks significantly increased the likelihood of missing a TDRT stimulus. No statistically significant differences were observed for visual and hybrid tasks. TDRT response time was not significantly associated with the difficulty level, regardless of task modality. In this study, the binary outcome TDRT miss was thus considered a more sensitive metric of cognitive workload than TDRT response time. TDRT response time can still be used to measure cognitive workload when tasks are relatively easy and the TDRT miss rate is close to zero. In addition, the sensitivity of the TDRT miss diminished for tasks that involved a visual component. Researchers who use TDRT to measure the cognitive workload associated with visual tasks should be aware of this limitation.