Volume 40 - n. 4 - October-December 2009


Sensitivity to fine-grained and coarse visual information: The effect of blurring on anticipation skill

Robin C. Jackson *, Bruce Abernethy * and Simon Wernhart **

(*) The University of Hong Kong, Hong Kong, S.A.R., China
(**) University of Graz, Austria

We examined skilled tennis players’ ability to perceive fine and coarse information by assessing their ability to predict serve direction under three levels of visual blur. A temporal occlusion design was used in which skilled players viewed serves struck by two players that were occluded at one of four points relative to ballracquet impact (-320ms, -160ms, 0ms, +160ms) and shown with one of three levels of blur (no blur, 20% blur, 40% blur). Using a within-task criterion to establish good and poor anticipators, the results revealed a significant interaction between anticipation skill and level of blur. Anticipation skill was significantly disrupted in the ‘20% blur’ condition; however, judgment accuracy of both groups then improved in the ‘40%blur’ condition while confidence in judgments declined. We conclude that there is evidence for processing of coarse configural information but that anticipation skill in this task was primarily driven by perception of finegrained information.

Keywords: EXpertise, Perception, Visual Cues



The influence of processing time on expert anticipation

John Baker *, Damian Farrow *, Bruce Elliott ** and Jacqueline Anderson **

(*) Sports Science and Sports Medicine, Australian Institute of Sport
(**) School of Sport Science, Exercise and Health, The University of Western Australia

This study investigated the influence of processing time on anticipatory skill. In a replication of Farrow, Abernethy and Jackson (2005) two different temporal occlusion paradigms were used to control the amount of processing time accompanying the appearance of specific kinematic information. A video presented dynamic images of a field hockey penalty corner drag flick that required expert and novice hockey goalkeepers to verbally predict the direction of the drag flick at the moment of occlusion. Prediction performance in a traditional progressive temporal occlusion approach, where more information is provided in each successive occlusion condition was compared to a moving window approach that showed the same kinematic information as introduced in the progressive condition but for a fixed viewing period. Consistent with the findings of Farrow et al. (2005) results demonstrated that the information pick up of the participants was similar in the two occlusion conditions suggesting that it is the kinematic content of the occlusion condition rather than processing time that is responsible for the anticipatory skill of the participants.

Keywords: Anticipation, Expert performance, Field hockey, Occlusion paradigms



Differences in oculomotor behaviour between elite athletes from visually and non-visually oriented sports

Stuart Morgan * and John Patterson **

(*) Biomechanics and Performance Analysis, Australian Institute of Sport, Belconnen, Australia
(**) Sensory Neuroscience Laboratory, Swinburne University of Technology, Australia

The oculomotor characteristics of elite athletes between differing sports have been largely overlooked. Instead the research focus has been dedicated to describing perceptual differences between elite and novice athletes within a given sport. Our aim was to compare and contrast the oculomotor attributes of elite groups of netball players, swimmers, and cyclists.We conducted a series of visual search experiments using a novel task that was unfamiliar to their domain of expertise. These sports were selected on the assumption they may entail differing visual processing demands, and that the adaptive visual search behaviour of each on an unfamiliar task may be different. The results revealed that the elite netball players generated saccadic eye movements more frequently than both the elite swimmers and the elite cyclists. Further, the mean amplitudes and mean peak velocities of saccades in the netball group were significantly higher than in the other groups. Importantly, analysis of the saccade main sequence showed that the netball group exhibited higher peak velocities for equidistant saccades compared to the other groups. These results suggest that there may be underlying differences in both the oculomotor capability and adaptive search behaviour of elite athletes from different sport backgrounds.

Keywords: Eye movements, Vision-for-perception, Netball, Swimming, Cycling, expertise



Representative task designs for the study of perception and action in sport

Matt Dicks *, Keith Davids ** and Chris Button *

(*) School of Physical Education, University of Otago, New Zealand
(**) School of Human Movement Studies, Queensland University of Technology, Australia

Empirical evidence indicates that an underlying antecedent of sports expertise is the ability of skilled athletes to successfully use predictive information to guide their anticipatory responses. This article discusses the nature of the relationship between expertise, perception and action using ideas from ecological psychology (Gibson, 1979) and representative task design (Brunswik, 1956). This conceptual framework suggests that a shortcoming of many research studies is a failure to accurately sample the performance environments of which skilled athletes have experience. It is proposed that the task constraints used to study perception and action should closely represent the specific performance contexts towards which investigators are attempting to generalise. Comparison of the research literature using in situ and video simulation experimental paradigms suggests that athletes’ performance may vary under different task constraints. These empirical findings need to be considered in future research on the study and training of perceptual skill.

Keywords: Perceptual skill, Ecological psychology, Task constraints, Anticipation



Developmental influences on the acquisition of tactical decision-making expertise

Jason Berry * and Bruce Abernethy **

(*) Essendon Football Club, Melbourne & School of Human Movement and Sports Sciences, University of Ballarat, Australia
(**) Institute of Human Performance, The University of Hong Kong & School of Human Movement Studies, The University of Queensland, Australia

The principal purpose of this study was to identify those developmental factors most predictive of adult perceptual and decision-making skill. Qualitative data on developmental experiences and social support were collected from semi-structured interviews of 29 elite Australian Football League (AFL) players, 16 of whom were independently classified by a panel of coaches as expert decision-makers and 13 as less-skilled decision-makers.While high levels of parental support and a fierce desire to win, established from an early age, were evident for all players in the elite sample, the expert decision-makers were more likely to have had (i) extensive experience of invasion games during their development, (ii) early experience of playing against adults or older children, (iii) playing experience in related sports (especially basketball), and (iv) their father as a coach at some stage during their junior years. The developmental characteristics observed for the expert decision-makers extend quantitative findings on the practice hours of the same cohort (Berry et al., 2008) and indicate that observable differences in decision-making skills amongst adult players, even at an elite level, may be directly linked to each player’s particular developmental and practice experiences.

Keywords: Development, Expertise, Practice



The influence of viewing perspective on decision-making and visual search behaviour in an invasive sport

David L. Mann */**, Damian Farrow **, Richard Shuttleworth ** and Melissa Hopwood **

(*) School of Optometry and Vision Science, University of New South Wales, Australia, Skill Acquisition, Australian Institute of Sport, Australia
(**) Skill Acquisition, Australian Institute of Sport, Australia

Perceptual-cognitive skill was examined in a film-based task displayed from two different viewing perspectives. Nineteen skilled youth football players observed identical simulations filmed from two different viewing perspectives; a ‘player’ perspective designed to simulate that experienced by a player in a game, and an ‘aerial’ perspective filmed from an elevated position overlying the same location on the field. Observation of the aerial perspective resulted in superior decisionmaking performance, most likely a reflection of the additional specifying information available from this viewpoint. Visual search recordings demonstrated increased time spent observing open space in the aerial perspective, along with more fixations of lesser duration primarily due to an increase in the referential fixation transitions between the player in possession of the ball and other attacking features. For both perspectives, participants fixated on the correct option however in the player view this correct option was chosen less frequently.

Keywords: Expertise, Eye movements, Simulation, Soccer



Knowledge base as a mechanism for perceptual-cognitive tasks: Skill is in the details!

Clare Macmahon * and Sue L.mcpherson **

(*) School of Sport and Exercise Science, Victoria University, Australia
(**) Department of Physical Therapy, Western Carolina University, USA

Perceptual-cognitive tasks used for both testing and training in sport will benefit from the inclusion and/or emphasis of knowledge base approaches as a key driving mechanism. In particular, training and testing of decision making skill is discussed. The distinction is made between the isolated decision making approach and the tactics and knowledge base approach to action choices. Knowledge base approaches are seen to provide a more sensitive and mechanistic assessment of skill and underlying response selection processes, and are better able to examine individual differences in the progression from action prediction to action control.

Keywords: Knowledge base Perceptual-cognitive skill, Sport expertise, Verbal report



Insights from Ecological Psychology and Dynamical Systems. Theory can underpin a philosophy of coaching

Ian Renshaw *, Keith Davids *, Rick Shuttleworth ** and Jia Yi Chow ***

(*) School of Human Movement Studies, Queensland University of Technology, Australia
(**) Australian Institute of Sport, Canberra, Australia
(***) Department of Physical Education and Sports Science, National Institute of Education, Nanyang Technological University, Singapore

The aim of this paper is to show how principles of ecological psychology and dynamical systems theory can underpin a philosophy of coaching practice in a nonlinear pedagogy. Nonlinear pedagogy is based on a view of the human movement system as a nonlinear dynamical system and has been basically defined as the application of concepts and tools of nonlinear dynamics to coaching practice. A systems orientation is adopted to show how nonlinear dynamical movement systems demonstrate an openness to environmental information flows, use inherent degeneracy to adapt movements to dynamic environments, show capacity for self-organisation, and fluctuate between stability and instability as changes in constraints on performance shape transitions in system organisation. We demonstrate how this perspective of the human movement system can aid understanding of motor learning processes and underpin practice for sports coaches. We provide a description of nonlinear pedagogy followed by a consideration of some of the fundamental principles of ecological psychology and dynamical systems theory that underpin it as a coaching philosophy. We illustrate how each principle impacts on nonlinear pedagogical coaching practice, demonstrating how they can substantiate a framework for the coaching process.

Keywords: Coaching practice, Dynamical systems, Ecological psychology, Non linear pedagogy, Task constraints



The use of motor learning in Biomechanics: A call for more collaboration

Alec Buttifield, Kevin Ball and Clare Mac Mahon

Centre for Aging, Rehabilitation, and Exercise Science School of Human Movement, Recreation, and Performance, Victoria University, Australia

Though biomechanics and motor learning are complimentary fields of study, few biomechanists have effectively combined the two. Biomechanics research has, in general, focussed on measurement techniques and ideal models of performance rather than how to use biomechanics as a tool to alter technique. Incorporating motor learning principles into biomechanics research is an important step not only for the understanding of learning principles but also the utilisation of biomechanical information in institutes and academies of sport around the world. This paper will briefly examine how research into augmented feedback, attentional focus and observational learning can be integrated into biomechanics research to aid in the successful alteration of an athlete’s technique.

Keywords: Biomechanics, Feedback, Observational Learning, Motor Learning



End-point focus of attention: Learning the ‘Catch’ in Rowing

Richard Parr and Chris Button

University of Otago, Dunedin, New Zealand

Initial research evidence suggests that learners may benefit from focussing their attention upon the demonstrated movement of a distal point of an action, also known as end-point trajectory matching. In the present study, verbal instructions were used by rowing coaches to promote either an end-point focus (i.e., the oar blade) or an internal focus of attention (i.e., the rower’s movements) amongst novice learners. The goal for the learners was to practice and improve the ‘catch’, which is the instant that the blade of the oar enters and locks onto the water. The learners were coached in 24 training sessions over a six-week period, they then rowed in retention and transfer tests seven weeks later. The End-point group showed improvements in technique (i.e., more effective and efficient oar placement in the water) at the end of the skill acquisition period and also in retention and transfer conditions. The Internal group did not show the same level of improvement by the end of the acquisition phase but did demonstrate some improvements by the retention and transfer tests. This study suggests that paying attention to the end-point is beneficial for novices learning complex, whole body movements (such as rowing) as well as for relatively simple, precision tasks.

Keywords: Attentional focus, Instructions, Motor Learning, Multi-articular action



The paradoxical role of cognitive effort in contextual interference and Implicit Motor Learning

Megan A. Rendell *, Rich S.w. Masters ** and Damian Farrow ***

(*) Australian Institute of Sport; Victoria University,Australia
(**) The University of Hong Kong
(***) Australian Institute of Sport, Australia

This paper critically reviews the issues that arise as a consequence of defining practice conditions in terms of the cognitive effort evoked. Two practice variables that suggest conflicting implications for cognitive effort are considered: the scheduling of practice conditions (contextual interference) and the accrual of task-relevant knowledge during practice (implicit/explicit motor learning). Practical implications of these two practice conditions are examined, specifically with regard to the skill level of a learner, the complexity of the to-be-learned tasks, and the ability of the learner to effectively perform under psychological pressure. It is hoped that these practical implications inspire researchers to seek more applied outcomes from their research.

Keywords: Blocked practice. Cognitive effort, Contextual interference, Implicit learning, Random practice