Christopher P. Bertram

The effect of Parkinson’s disease on the control of multi-segmental coordination

An experiment was designed to test whether or not Parkinsons disease (PD) patients were able to maintain endpoint kinematic patterns in a prehension task involving movement of the torso. Nine PD patients and nine healthy controls were asked to reach for and grasp a full cup of water that was either covered or uncovered and placed beyond the reach of the outstretched arm. An OPTOTRAK (Northern Digital) 3-dimensional motion analysis system was used to capture the movement of four markers placed on the arm, hand, and torso. The results indicated the Parkinsons patients had a decreased ability to maintain the kinematics of the end effector. The PD patients were also found to be impaired in terms of their ability to synchronize the arm, hand, and torso. More specifically, although the elderly controls seemed to employ a strategy of increasing the involvement of the torso when reaching to grasp the uncovered cup, no such strategy was observed in the PD patients. Collectively, the results suggest that the multi-joint synergies observed in the elderly controls, which help preserve relatively consistent endpoint trajectories, are disrupted in Parkinsons patients.

Games as neurofeedback training for children with FASD

Biofeedback games help people maintain specific mental or physical states and are useful to help children with cognitive impairments learn to self-regulate their brain function. However, biofeedback games are expensive and difficult to create and are not sufficiently appealing to hold a childs interest over the long term needed for effective biofeedback training. We present a system that turns off-the-shelf computer games into biofeedback games. Our approach uses texture-based graphical overlays that vary in their obfuscation of underlying screen elements based on the sensed physiological state of the child. The textures can be visually customized so that they appear to be integrated with the underlying game. Through a 12-week deployment, with 16 children with Fetal Alcohol Spectrum Disorder, we show that our solution can hold a childs interest over a long term, and balances the competing needs of maintaining the fun of playing, while providing effective biofeedback training.

Pointing to an allocentric and egocentric remembered target in younger and older adults.

Previous reports have shown that older adults have difficulties in maintaining allocentric information in memory but not egocentric information. The present study evaluated pointing accuracy in younger and older adults for egocentric and allocentric task. The task was to localize and maintain one, two, or four target locations. Target(s) were presented with or without a surrounding white square in a dimly lit environment. Despite previous postulations, the results of the present study revealed that older adults were able to point to remembered egocentric and allocentric targets as accurately as younger adults regardless of task difficulty. However, older adults took more time pointing to allocentric targets as compared to younger adults. The longer movement time was caused by a lengthening of the deceleration phase, suggesting that during pointing, older adults rely more on visual information surrounding the target than younger adults.

On the Use and Misuse of Video Analysis

The popularity of video analysis in sports in general, and golf in particular, has recently risen. However, research in the area of video analysis has lagged well behind these trends in current coaching practice. The current study was designed to assess changes in performance as a result of using video feedback as part of an instructional session. Forty-eight golfers (24 novices; 24 skilled players) performed a pre-test in which twelve swings were recorded using an indoor launch monitor system. The participants were then randomly assigned to a lesson in one of three groups: 1) Verbal coaching (V), 2) Verbal +Video coaching (V+V), and 3) Self-Guided (SG) practice. All groups were then retested to determine the extent to which the various training conditions impacted overall swing characteristics. The results indicated that the positive effects of video feedback were: A) limited in scope, and b) observed to a greater extent in more skilled performers. The results suggest that while more skilled players were able to glean useful timing information from video feedback, these same conditions may in fact impede the learning process in novice performers.

Salivary cortisol levels are elevated in the afternoon and at bedtime in children with prenatal alcohol exposure

Prenatal alcohol exposure can cause dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, which may underlie some of the behavioral and adaptive problems seen in individuals with Fetal Alcohol Spectrum Disorders (FASD). Infants prenatally exposed to alcohol show altered basal and post-stress cortisol levels, but it is unknown if this persists beyond 2 years of age. It is also unknown if cortisol levels can be normalized through intervention programs. In this study, we investigated the effects of a physical activity program for children with FASD to determine: 1) if HPA dysregulation persists in school-age children with FASD, and 2) the effect of our program on cortisol levels. Twenty six children (ages 6-14 years) with FASD participated in an 8 week motor skill development program. Salivary cortisol levels were measured in 24 children and compared at 4 time points: before, immediately after, 3 months, and 1 year after program completion. Cortisol levels were also compared to 32 control children to evaluate the long-term effects of prenatal alcohol exposure on HPA regulation. For each time point, saliva was collected on each of 2 days at 3 times in the diurnal cycle: awakening, after school, and just before bedtime. Cortisol levels were significantly higher in the afternoon and at bedtime in children with FASD with confirmed prenatal exposure to high levels of alcohol (alcohol exposure rank 4), compared with Control children or children with FASD with exposure to low or unknown levels of alcohol (alcohol exposure rank 3). The program did not significantly affect cortisol levels in children with FASD as a group. These results provide support for long-term effects of prenatal alcohol exposure on the HPA system in humans, which could increase vulnerability to mental health issues and diseases later in life.

The Effects of Custom-Fitted Clubs Versus "Placebo" Clubs on Golf-Swing Characteristics

While the use of custom-fitted equipment is on the rise in the game of golf, empirical data as to its benefits and/or pitfalls is lacking. The current study sought to determine the effectiveness of custom-fitted clubs in the golf swing performance of both novice and experienced golfers. A launch monitor system was used to obtain measures of clubhead speed, clubface angle, and tempo to quantify baseline performance and any subsequent change in performance following the experimental procedures. Following a pre-test, which involved recording 12 swings with a standard 6-iron, participants were custom fit for club length, shaft flex, and lie angle according to the Henry-Griffitts TotalTest® system. Post-tests were administered following a 10-minute break. During the post-test, participants unknowingly used either a properly fitted club, a purposely ill-fitted (i.e., ‘placebo’ club), or the same standard club used in the pre-test. Our data suggest that custom club fitting does improve the characteristics of the golf swing, although often in different ways depending upon the skill level of the player.

Leading Article: Discovering Golf's Innermost Truths: A New Approach to Teaching the Game

INTRODUCTION Peter Lightbown brings interesting and varied schools of thought to the teaching and learning of the golf swing in his target article. He discusses how his frustration with traditional teaching methods grounded in technical and mechanical analyses led him to a more ‘inward’ search for answers on how to better his golf game. There are some thought-provoking concepts, many of which have been empirically tested and our understanding of brain/body interaction is advancing in many interesting directions.

Selective Attention in Golf: Managing the Keys to the Door

An information processing approach is taken to explain the concept of selective attention as it occurs in planning and executing the golf swing. Selective attention is likened to a door that has access to the central planning and execution centres. Principles of controlling the door to allow only relevant information to enter the movement planning and execution processes are discussed. Practical implications of this information processing model are given.