Papers by Kathleen Haywood
Research Quarterly for Exercise and Sport, Sep 1, 1991
Research Quarterly for Exercise and Sport, Mar 1, 1998
Current Eye Research, 1986
Physiologically healthy elderly individuals often exhibit visual deficits which result from age-r... more Physiologically healthy elderly individuals often exhibit visual deficits which result from age-related changes in both the transmission characteristics of the ocular media and the functional properties of the neural elements in the visual pathway. Many of the age-related changes in the optical quality of the ocular media have been identified, but the age-dependent variations in visual neurophysiology have not been clearly delineated. This investigation examined age-related alterations in pattern-specific biopotentials generated in the human retina and visual cortex. Counterphasing (2.0 and 7.5 rps) patterns (7.5', 15', 30' and 60' checks) were used to simultaneously monitor pattern-reversal visual evoked potentials (PRVEPs). Young visual normals (20-30 years of age) and healthy elderly observers (70-80 years of age) with visual acuity of 20/30 or better were studied. All data were corrected for the effects of senile miosis on retinal illumination. Significant variations in the waveform characteristics of both biopotentials were noted for the elderly individuals. PRRP amplitude was uniformly reduced for all stimulus conditions. PRVEP amplitude reductions were also noted but were more stimulus specific than the PRRP amplitude reductions. No significant PRVEP or PRRP latency changes were observed. These results suggest that alterations in the physiological properties of neural elements in both the retina and visual cortex are associated with normal aging.
The Encyclopedia of Child and Adolescent Development, Jan 13, 2020
British Journal of Sports Medicine, Dec 1, 1980
Simple anthropometric measures, flexibility, and strength performance tests were conducted on 30 ... more Simple anthropometric measures, flexibility, and strength performance tests were conducted on 30 young gymnasts and repeated one year later. During the intervening year, 13 gymnasts, average age 14.5 at the second year, reached menarche, while the remaining 17, average age 14.1 years, did not. Multivariate analyses of covariance were calculated to test for differences between the groups at Year 2, using the Year 1 scores as covariates. No significant differences between the groups were found. Tendencies to linearity of physique and late maturation, noted in the literature among very skilled gymnasts, seemed to be confirmed among this group of local competitors.
Journal of Aging and Physical Activity, Oct 1, 1993
Older adults threw tennis balls for force and accuracy to examine their adaptability to different... more Older adults threw tennis balls for force and accuracy to examine their adaptability to different task demands. Twenty-one (13 women, 8 men) participants were videotaped as they performed five force and five accuracy throws. The developmental level of each throw was determined; resultant ball velocities also were examined. Roberton's (1977, 1978) movement components were used in the former analysis. The typical pattern of gender differences occurred for both movement component and velocity measures. Men performed at higher levels than women. Only minor force versus accuracy differences were found in the movement patterns used by either men or women; none of these differences were significant. Clear task differences occurred for ball velocities. Men's forceful throws were faster than those for accuracy; women's throws did not differ for the two tasks. The generally lower developmental level of women's throws accounted for gender differences in velocity. Insufficient task differences may explain the lack of clear contrast in movement patterns.
Journal of Sports Sciences, Sep 1, 1984
Abstract Movement is visually detected by one of two systems: (a) the image‐retina system (image ... more Abstract Movement is visually detected by one of two systems: (a) the image‐retina system (image moves along stationary retina), or (b) the eye‐head movement system (eye moves to keep image stationary on retina). Previous research has shown that subjects, when they have to respond to movement to execute a coincidence‐anticipation task, will choose the image‐retina system or the eye‐head system, but it has failed to establish the superiority of either system. The present study was designed to examine this issue. Young adults (n = 28) of both sexes performed two series of 12 coincidence‐anticipation trials each. Three stimulus speeds were administered in a randomized order, standardized across subjects. Eye movements were recorded with the head stabilized. In one series, subjects were instructed to follow the stimulus with their eyes. In the other, they were told to fix on the target point and watch the stimulus in their peripheral vision. Half of the subjects initiated testing in each condition. Time error...
Research Quarterly for Exercise and Sport, Dec 1, 1981
Journal of Motor Behavior, Dec 1, 1977
The present study related visual processing, as indicated by eye movements, to performance accura... more The present study related visual processing, as indicated by eye movements, to performance accuracy on coincidence-anticipation tasks. Three age groups were tested on a coincidence-anticipation task and their eye movements recorded. Three levels of response were administered under three levels of stimulus speed. A MANOVA indicated that both eye tracking and coincidence-anticipation varied among the age groups and with stimulus speed, although in different directions. Eye tracking error decreased with increasing age but only the coincidence-anticipation response accuracy of the youngest group appeared to be less accurate than that of the adults. Eye tracking error also decreased with decreasing stimulus speed but coincidence-anticipation performance was least accurate at the slow speed. Coincidence-anticipation error was the major contributor to performance differences with changes in the type of response.
Experimental Aging Research, Sep 1, 1980
Improvement in response speed through young adulthood and decline in older adulthood has been con... more Improvement in response speed through young adulthood and decline in older adulthood has been consistently demonstrated. There is indication of a similar trend in coincidence-anticipation accuracy, wherein the performer predicts the arrival of a moving stimulus at a target point, although performance appears to plateau earlier and performance by older adults has not been studied. Four age groups, 7-9, 11-13, 18-32, and 60-75 years, were observed on a coincidence-anticipation task requiring a thumb-press response and on a maximal response-time task. Speeds of the sequential-light stimulus of the former were 2 through 5 MPH. While findings confirmed age trend in response speed, only the youngest children performed significantly poorer than the others in coincidence-anticipation accuracy. More variable or less accurate performance at extreme stimulus speeds characterized this youngest group. A more sedentary group of adults, 64 to 86 years, was tested in a follow-up experiment. The analysis indicated that older adults showed little directional bias but performed less accurately and more variably than young adults.
Research Quarterly for Exercise and Sport, Jun 1, 1991
The high physical inactivity that young students present makes it necessary to carry out studies ... more The high physical inactivity that young students present makes it necessary to carry out studies that seek to know the reasons for this situation and seek proposals for its improvement. The aim of this study was to analyze the characteristics that define high school students of a schools with a program (Sport Project Centre) to promote physical activity in Galicia in terms of physical activity, gender and age rate. The sample is composed of 1697 subjects (824 boys and 873 girls) and 2335 parents. "The International Questionnaire about Lifestyles in Students" was used as an instrument of data collection. The results suggest that 66.9% of students have a low or very low rate of physical activity (56% boys and 77.3% girls) and 33,1% as active or very active (44% boys and 22.7% girls). This study provides evidence that there are gender and age differences when when quantifying the number of hours of physical activity. In addition, there is a dissociation between the practice perception and what is actually realized. There is also a significant relationship between the practice of physical activity and gender, not being the same when analyzing the academic course.In conclusion, there is a high physical inactivity, especially in females, together with a lack of knowledge of this situation, both from the students and their parents.
Journal of Aging and Physical Activity, 1995
This study examined tennis serving in older adult tennis players. Twentytwo older adults, divided... more This study examined tennis serving in older adult tennis players. Twentytwo older adults, divided into younger and older halves, were videotaped serving five "first" serves. Dominant shoulder flexibility also was measured. From the videotape, servers were classified into developmental levels and their resultant ball impact velocity was calculated. An Age x Gender (2 x 2) mixed model MANOVA yielded no significant differences between the age groups or between men and women in flexibility, ball impact velocity, or movement pattern. A few combinations of the developmental levels of elbow and forearmlracket action were used by the majority of servers. Regular practice might consolidate older adults in these attractor movement patterns, making them more resilient to change than with less practiced skills. These results suggest practice in older adulthood favorably affects performance by resulting in consistency of movement pattern and maintenance of movement pattern, flexibility, and ball impact speed.
Journal of Motor Behavior, Dec 1, 1975
The relative effects of three knowledge of results (KR) treatments on performance of a complex co... more The relative effects of three knowledge of results (KR) treatments on performance of a complex coincidence-anticipation task requiring speed and accuracy were studied. Male volunteers (n=75) were assigned to one of three treatments: no KR, quantitative KR, or qualitative KR. No significant differences in the performance of treatment groups were found. It was suggested that the task itself may have provided enough information for fairly accurate performance.
Journal of Aging and Physical Activity, Apr 1, 1996
Older adults were tested to clarify findings of an earlier examination of movement responses to s... more Older adults were tested to clarify findings of an earlier examination of movement responses to shifting task requirements (Williams et al., 1993). Eleven participants (average age = 77 years) were evaluated on form and velocity as they performed overarm throws for force and accuracy. Significant gender and force-accuracy differences occurred for resultant velocity. Although no statistically significant differences occurred for force-accuracy comparisons of movement form, there were trends toward change in most movement components. Additionally, many individuals displayed change in one or more components as they shifted from force to accuracy throws. Results of this study point to the importance of examining developmental status and task requirements simultaneously.
Research Quarterly for Exercise and Sport, Mar 1, 1983
Women in Sport and Physical Activity Journal, Oct 1, 1996
Both environmental and biological factors have been cited to explain large gender differences in ... more Both environmental and biological factors have been cited to explain large gender differences in throwing. Because differences are observed as early as three years, some researchers have suggested biological differences may be a primary factor (Nelson et al., 1986). To explore the contribution of these factors more carefully, three groups of children, 7-8 years, 9-10 years, and 11-12 years, were videotaped performing ten forceful overarm throws each with their dominant and nondominant hands. Resultant ball velocities were computed across all trials for each hand. Five trials for each arm, for each participant were categorized using Roberton’s (Roberton & Halverson, 1984) movement components for the overarm throw. Overall significant age differences were obtained for ball velocities for both dominant and nondominant arms, but gender differences were demonstrated only for the dominant arm. Ball velocity differences for the nondominant arm were not evident. Minimal differences in form occurred for the nondominant arm. When the nondominant arm exhibited coordination patterns and performances typical of an unpracticed performer, we suggest that nonbiological factors are important in explaining the large gender differences in throwing widely noted in the literature.
The purpose of this study was to determine the relative effects of three treatments of knowledge ... more The purpose of this study was to determine the relative effects of three treatments of knowledge of results on the acquisition of an open complex motor skill requiring speed and accuracy (coincidence-anticipation). Seventy-five male undergraduate students enrolled at Washington University volunteered as subjects. The subjects were randomly assigned to one of three treatment groups. One group was given informative knowledge of results, another group positively reinforcing knowledge of results, while the third group was given no supplementary knowledge of results. All subjects were given thirty trials on a coincidence-anticipation task which required the subject to make a motor response at the time a moving object coincided with two separated stationary objects. Two responses were made on each trial, a fine motor movement was required on the first response, but a large motor movement was required before the second response. A three-way analysis of variance, with one between-groups variable and two within-group variables, was performed by the :MAIL computer program. Results showed no significant differences in performance among the treatment groups on the first or second response, based on either trial means or total-group means. There was only a .52 correlation between performance on the first and second responses. It was concluded, within the limitations of this study, that informative and reinforcing lalowledge of results were no more beneficial to the performance of the present coincidenceanticipation task than the intrinsic feedback inherent to the task. Based on trial means, there appeared to be no tendency for the treatment groups to improve in performance over trials.
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Papers by Kathleen Haywood