Decision making in slow and rapid reaching : Sacrificing success to minimize effort

Acknowledgement This work was supported by the James S. McDonnell Foundation (Scholar Award to ARH). Supplementary Material Data available at: https://zenodo.org/record/3604284Peer reviewedPostprin

A New Approach to Intelligent Assistance: Cognitive Shadow

We introduce a prototype intelligent cognitive assistant that continuously learns the decision pattern of the user online, instantly recognizes deviations from that pattern as potential errors and then alerts the user accordingly. The decision model built by the cognitive assistant (henceforth, referred to as the “Cognitive Shadow”) through its interaction with an expert can potentially outperform the human decision maker – as humans are vulnerable to fatigue and distraction and may deviate from their expert decision pattern. Formally capturing expert mental models is wellknown to be a major challenge for the system engineering of decision support solutions since decision makers are often not fully aware of – or cannot verbally express – the basis for their expert judgments. However, successful elicitation and formalization of expert mental models have the potential to provide the underlying algorithms for designing cognitive assistants capable of improving decision quality by recognizing errors in cases where the decision maker is diverging from his usual judgment patterns

No one knows what attention is

In this article, we challenge the usefulness of “attention” as a unitary construct and/or neural system. We point out that the concept has too many meanings to justify a single term, and that “attention” is used to refer to both the explanandum (the set of phenomena in need of explanation) and the explanans (the set of processes doing the explaining). To illustrate these points, we focus our discussion on visual selective attention. It is argued that selectivity in processing has emerged through evolution as a design feature of a complex multi-channel sensorimotor system, which generates selective phenomena of “attention” as one of many by-products. Instead of the traditional analytic approach to attention, we suggest a synthetic approach that starts with well-understood mechanisms that do not need to be dedicated to attention, and yet account for the selectivity phenomena under investigation. We conclude that what would serve scientific progress best would be to drop the term “attention” as a label for a specific functional or neural system and instead focus on behaviorally relevant selection processes and the many systems that implement them.Action Contro

fMRI neurofeedback in the motor system elicits bidirectional changes in activity and in white matter structure in the adult human brain

White matter (WM) plasticity supports skill learning and memory. Up- and downregulation of brain activity in animal models lead to WM alterations. But can bidirectional brain-activity manipulation change WM structure in the adult human brain? We employ fMRI neurofeedback to endogenously and directionally modulate activity in the sensorimotor cortices. Diffusion tensor imaging is acquired before and after two separate conditions, involving regulating sensorimotor activity either up or down using real or sham neurofeedback (n = 20 participants × 4 scans). We report rapid opposing changes in corpus callosum microstructure that depend on the direction of activity modulation. Our findings show that fMRI neurofeedback can be used to endogenously and directionally alter not only brain-activity patterns but also WM pathways connecting the targeted brain areas. The level of associated brain activity in connected areas is therefore a possible mediator of previously described learning-related changes in WM

Convergent validity and inter-rater reliability of a lower-limb multimodal physical function assessment in community-dwelling older adults

Introduction: Lower-limb physical function declines with age and contributes to a greater difficulty in performing activities of daily living. Existing assessments of lower-limb function assess one dimension of movement in isolation or are not time-efficient, which discourages their use in community and clinical settings. We aimed to address these limitations by assessing the inter-rater reliability and convergent validity of a new multimodal functional lower-limb assessment (FLA).Methods: FLA consists of five major functional movement tasks (rising from a chair, walking gait, stair ascending/descending, obstacle avoidance, and descending to a chair) performed consecutively. A total of 48 community-dwelling older adults (32 female participants; age: 71 ± 6 years) completed the FLA as well as timed up-and-go, 30-s sit-to-stand, and 6-min walk tests.Results: Slower FLA time was correlated with a slower timed up-and-go test (ρ = 0.70), less sit-to-stand repetitions (ρ = −0.65), and a shorter distance in the 6-min walk test (ρ = −0.69; all, p < 0.001). Assessments by two raters were not different (12.28 ± 3.86 s versus 12.29 ± 3.83 s, p = 0.98; inter-rater reliability ρ = 0.993, p < 0.001) and were statistically equivalent (via equivalence testing). Multiple regression and relative weights analyses demonstrated that FLA times were most predicted by the timed up-and-go performance [adjusted R2 = 0.75; p < 0.001; raw weight 0.42 (95% CI: 0.27, 0.53)].Discussion: Our findings document the high inter-rater reliability and moderate-strong convergent validity of the FLA. These findings warrant further investigation into the predictive validity of the FLA for its use as an assessment of lower-limb physical function among community-dwelling older adults

Motor Performance in the Context of Externally-imposed Payoffs

Humans need to rapidly select movements that achieve their goal while avoiding negative outcomes. The processes leading to these decisions have only recently been studied. In the typical paradigm used to gain insight into the decision process, participants aim to a target circle that is overlapped by a penalty circle. They receive 100 points for hitting the target, and lose points for hitting the penalty region. Previous research has shown that participants generally behave like a rational decision maker by adapting their endpoint when the distance between the target and penalty circle and the penalty value changes (although some suboptimal selection has been noted). The overall purpose of the research reported in the present thesis was to determine if there are contexts when participants’ behaviour is suboptimal in a rapid, motor decision making tasks. Taken together, the results from four studies showed that: 1) participants require experience and feedback to aim to optimal locations; 2) participants often aimed closer to target center than optimal; and, 3) probability (represented through spatial parameters) has more influence over participant’s motor decisions than does the value of the penalty. Therefore, participants’ actions do not necessarily conform to a rational model of decision making; rather, there are consistent biases arising in the selection, planning, and execution of actions in specific contexts. These findings and conclusions can lead to a more descriptive understanding of motor decision making to provide information that is in addition to prescriptive models of rational behaviour.Ph

IInterface Design for an Automated Combat Identifcation System: Displaying Reliability Information

Users have difficulty relying on automated combat identification aids; however, verbally informing users of the automation reliability has helped them rely on the automation more appropriately. A number of interfaces that displayed automation reliability information in real time were developed and tested. In Experiment I, participants used the interfaces in the IMMERSIVE simulation, a first person shooter game. The results showed that the form of the interface affected both reliance on the automation and sensitivity in discriminating hostile and friendly targets. The difference in sensitivity and reliance may be attributed to how participants allocated their attention among the displays. In Experiment II, still combat scenes were presented to the participants for 400 or 800 milliseconds (as opposed to 10 seconds in Experiment I) to place additional time stress on attention resources. The results replicated the results of Experiment I, but sensitivity measures showed a dependence on reliability of the automation.MAS

The Role of Therapeutic Recreation in the Care of Individuals with Acquired Brain Injuries: A Scoping Review Protocol

As resources and opportunities for publishing are scarce among recreation therapists working clinically, there are few publications describing the role of TR in the context of ABI care. However, in order for the field of TR to continue growing, it must have evidence of its impactful contributions. This review will aim to synthesize the available evidence in the hopes of highlighting the need for further works describing the impact of TR in different ABI care settings