Lawrence E. M. Grierson

The minimal relationship between simulation fidelity and transfer of learning

Medical Education 2012

Goal-Directed Aiming: Two Components but Multiple Processes

This article reviews the behavioral literature on the control of goal-directed aiming and presents a multiple-process model of limb control. The model builds on recent variants of Woodworths (1899) two-component model of speed-accuracy relations in voluntary movement and incorporates ideas about dynamic online limb control based on prior expectations about the efferent and afferent consequences of a planned movement. The model considers the relationship between movement speed and accuracy, and how performers adjust their trial-to-trial aiming behavior to find a safe, but fast, zone for movement execution. The model also outlines how the energy and safety costs associated with different movement outcomes contribute to movement planning processes and the control of aiming trajectories. Our theoretical position highlights the importance of advance knowledge about the sensory information that will be available for online control and the need to develop a robust internal representation of expected sensory consequences. We outline how early practice contributes to optimizing strategic planning to avoid worst-case outcomes associated with inherent neural-motor variability. Our model considers the role of both motor development and motor learning in refining feed-forward and online control. The model reconciles procedural and representational accounts of the specificity-of-learning phenomenon. Finally, we examine the breakdown of perceptual-motor precision in several special populations (i.e., Down syndrome, Williams syndrome, autism spectrum disorder, normal aging) within the framework of a multiple-process approach to goal-directed aiming.

Action representations in perception, motor control and learning: implications for medical education.

Medical Education 2011: 45: 119–131

Information Processing, Specificity of Practice, and the Transfer of Learning: Considerations for Reconsidering Fidelity.

Much has been made in the recent medical education literature of the incorrect characterization of simulation along a continuum of low to high fidelity (Cook et al. JAMA 306(9): 978–988, 2011; Norman et al. Med Educ 46(7): 636–647, 2012; Teteris et al. Adv Health Sci Educ 17(1): 137–144, 2012). For the most part, the common definition within the medical education community has been that simulations that present highly realistic performance characteristics, contexts, and scenarios are referred to as high-fidelity, while simulations that reduce to-be-learned skills to simpler constructs or constituent parts are referred to as low-fidelity. The issue with this is that highly-realistic has tended to mean the degree to which the simulation looks like the criterion context with little regard for what features of the simulation are in fact relevant to the skill that the educator hopes to teach. The inherent assumption that high fidelity simulations lead to better learning—an assumption for which there is a lack of supporting evidence (Norman et al. Med Educ 46(7): 636–647, 2012)—only exacerbates the problem. So much so that some have suggested that the term be abandoned all together (Hamstra et al. Acad Med J Assoc Am Med Coll 2014). While, it is true that fidelity and its importance are misconstrued in the medical education literature, the construct, defined classically as the degree of faithfulness that exists between two entities, is still fundamental to understanding the effectiveness that any one simulation might have in preparing learners for clinical performance. However, the concept of simulation fidelity must be recast in terms of the fundamental information processing events that underpin human performance.

Application of a Tactile Way-Finding Device to Facilitate Navigation in Persons With Dementia

Persons with dementias, such as Alzheimers disease, have well‐documented deficiencies in way-finding, which often renders these individuals house bound and/or unable to perform daily activities without significant frustrations. A wearable belt has recently been developed that may have the capability to facilitate navigation for this population. Through a series of four small, vibrating motors that are adjusted to the cardinal positions of front, back, right, and left, the belt provides wearers with a tactile signal indicating the direction to their destination. In this experiment, the applicability of the way-finding signals to persons with dementia was assessed. To do so, participants walked a series of routes through the corridors of a hospital while wearing the belt. The results suggest the way-finding belt has potential as a navigation aid for individuals with dementia. The participants displayed a few deficiencies in attending to the directional signals that led to way-finding errors in which the signal was ignored and the intended turn not made. The article concludes with recommendations that the system of signal delivery be modified in a way that captures and directs the wearers focus more prominently to the vibrotactile stimulus.

The role of collaborative interactivity in the observational practice of clinical skills.

Medical Education 2012: 46: 409–416

The roles of deliberate practice and innate ability in developing expertise: evidence and implications

Medical education research focuses extensively on experience and deliberate practice (DP) as key factors in the development of expert performance. The research on DP minimises the role of individual ability in expert performance. This claim ignores a large body of research supporting the importance of innate individual cognitive differences. We review the relationship between DP and an innate individual ability, working memory (WM) capacity, to illustrate how both DP and individual ability predict expert performance.

Optimising speed and energy expenditure in accurate visually directed upper limb movements

Traditional models of speed–accuracy relations and limb control are steady-state models that fail to consider the learning history and strategic approach of the performer. Work from this laboratory indicates that a performer adjusts his/her behaviour from trial-to-trial to optimise not only the speed and accuracy of performance, but also energy expenditure. Because some errors have greater temporal and energy costs than others, most performers execute movements that are prepared such that potential errors are of minimal expense. The trajectories and subsequent endpoint distributions of rapid aiming movements depend on advance knowledge about the availability of afferent information for online control, as well as the costs associated with undershooting or overshooting the target position with the initial impulse. With practice, a performer is able to reduce the trial-to-trial variability associated with goal-directed movement through more consistent movement planning processes and more rapid online control. Part of the optimisation process is related to the development of an internal model of performance against which early afferent feedback can be evaluated. This framework for examining speed, accuracy and energy expenditure in goal-directed reaching can be used to help understand the breakdown of efficient limb control due to fatigue, ageing and pathology.

Kinematic analysis of goal-directed aims made against early and late perturbations: An investigation of the relative influence of two online control processes

Examination of goal-directed movements has evidenced two processes of visually regulated online control: early trajectory control that operates to make movement adjustments on the basis of limb velocity comparisons to internally generated models of the expected limb velocity, and late trajectory control that uses allocentric information about the limb and target positions. The results of experiments using illusory perturbations suggest that the two systems have an additive influence on movement outcome, and are relatively independent. In this theoretical context, three experiments were conducted in which actual perturbations to the aiming limb dynamics and the tasks demands were introduced. Compressed air expulsed through a stylus, in the direction of, or opposite to, that of the movement was used to impact limb velocity and the target location was moved at movement initiation to impact late evaluation of target and limb position. The results of the compressed air-only and moving target-only conditions replicated the previous evidence of early and late control, respectively. Interestingly, movement accuracy measures yielded an interactive effect of the two perturbations when presented in tandem. It appears that the perturbations prompted parallel operation of the two control processes.

Evaluating the impact of high- and low-fidelity instruction in the development of auscultation skills

A principal justification for the use of high‐fidelity (HF) simulation is that, because it is closer to reality, students will be more motivated to learn and, consequently, will be better able to transfer their learning to real patients. However, the increased authenticity is accompanied by greater complexity, which may reduce learning, and variability in the presentation of a condition on an HF simulator is typically restricted.