Kathleen M. Haywood

Eye Movements While Viewing a Baseball Pitch

Information-processing theory predicts that sport performers gain information from their environment through use of a systematic pattern of eye movements/fixations. Of interest here was the visual-search pattern used in viewing an oncoming baseball pitch and whether this pattern differed for expert and novice batters. Ocular latencies were also examined during the task. Subjects were 9 varsity collegiate baseball players (expert) and 9 novice players. Each subject was shown 20 pitches on videotape, with the type of pitch (curve, fastball) and type of motion (wind-up, stretch) varied During the viewing eye movements were recorded by a photoelectric technique. Expert players fixated during wind-up on the anticipated release point and then, after a latency of about 150 msec. following release, moved their eyes to the oncoming ball. Novice batters tended to move their eyes before release or to fixate somewhere other than the release point, such as the pitchers head. Performance differences in hitting may be partially attributable to these differences in visual search pattern. This latter finding supports the information-processing viewpoint, yet the existence of an eye-movement latency supports a direct perception perspective.

Coincidence-anticipation accuracy across the life span

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.

Eye Movements During Coincidence-Anticipation Performance

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.

Contextual Factors and Age Group Differences in Coincidence-Anticipation Performance

Abstract Age group differences in the direction of anticipatory motor responses may be attributable to the increased susceptibility of young children to contextual factors. That is, their performances on a given trial may be influenced by the stimulus speed presented in the previous trial. Mixed-sex groups of 8–9 year-olds and adults were given 3 blocks of 18 coincidence-anticipation trials each in a counterbalanced design. One block contained stimulus speeds of 1, 3, or 5 MPH, another speeds of 3, 5, or 7 MPH, and a third speeds of 5, 7, or 9 MPH, so that the 5 MPH speed was common to all blocks. An age group by sex by testing order by trial block ANOVA of constant error on the 5 MPH trials indicated that trial block was a significant factor within an age group by block interaction. Mean scores showed that the children responded very early in the 5–7–9 MPH block to the 5 MPH stimuli while the adults did not. Testing order was also a significant factor: subjects in the 1–3–5, 5–7–9, 3–5–7 MPH order perfor...

Use of the image‐retina and eye‐head movement visual systems during coincidence‐anticipation performance

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...

Relative Effects of Three Knowledge of Results Treatments on Coincidence-Anticipation Performance

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.

Changes in Throwing by Older Adults: A Longitudinal Investigation

This investigation examined change in a motor pattern requiring multisegmented coordination in older adults. The overarm throw was observed longitudinally in 8 elderly individuals over 7 years. Data were evaluated using Robertons (Roberton & Halverson, 1984) movement components. Contrasting the assumed pattern of aging, only small declines in movement form were observed. Individual cases revealed additional, noncategorizable declines within component categories, including slower movement speed and decreased range of motion. Increased trial-to-trial variability also was associated with change. These changes suggested that elderly participants coordinated their movements in a manner similar to younger participants but controlled them differently. The small changes observed in this investigation suggest that performance, at least for some skills, is more stable than traditionally assumed.

Responses to Speed Changes in Coincidence-Anticipation Judgments after Extended Practice

Abstract Coincidence-anticipation performance has been found to vary with changes in the speed of the tasks stimulus. This may be due to bias effects. The present study was designed to investigate the existence of directional error, its persistence after extended practice, and its occurrence upon transfer to new contextual stimuli. Two groups of 20 women athletes each were tested for 270 trials over 3 days on a Bassin anticipation task. One group judged stimulus speeds of 2, 3, and 4 mph and the other group speeds of 2, 4, and 6 mph. Both groups improved during training, but tended to respond late, less accurately, and more variably to the slowest speed. Following a 30-trial warmup on Day 4, the second group transferred to the same speeds given the first group. Following transfer, the Transfer Group demonstrated increased directional bias to the slowest stimulus speed despite having seen this speed throughout training. By the second block of trials following transfer, however, they were performing at an ...

THROWING PATTERNS OF OLDER ADULTS: A FOLLOW -UP INVESTIGATION·

Previous investigations of the movement patterns of older adults have focused on functional movements. Performance declines have been reported with increasing age. Many investigations, however, do not require older adults to perform maximal, force producing actions. Smaller declines might be observed if older adults made a maximal effort. This investigation examined changes in a maximal skill—the overarm throw for force. Active, older adults were videotaped as they threw tennis balls. Thirteen people were filmed for two consecutive years. Gender and age differences were examined for movement patterns, ball velocity, and selected kinematic measures. Participants threw using patterns and velocities generally observed in children in middle elementary-school years. This result suggested there was a decline in this force production skill. Some older adults regressed in the movement patterns they used over the two years of testing. Older males threw faster, using more advanced movement patterns than older females.

Eye movement pattern and accuracy during perceptual-motor performance in young and old adults

Differences between young and old adults in matching a motor response to arrival of a moving stimulus may be partially attributable to age group differences in eye movements. In Experiment 1 the eye movement patterns used by young and old adults during performance of a coincidence-anticipation task were recorded. Age group differences in preferred pattern were noted but did not appear to be linked to task performance level. In Experiment 2, eye tracking error was recorded for young adults and many of the old adults tested in Experiment 1. Age group differences were attributable to task performance rather than eye tracking error. Further, the preferred eye movement pattern did not appear to be stable over time among the subjects retested. The eye-movement reaction time of the old adults was significantly longer than that of the young adults, but this did not appear to hamper the ability of the old adults to distinguish the stimulus speeds. Little evidence was found for linking visual search to task performance error.