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N L Goggin

Publications and source records attributed to N L Goggin.

7 recordsLinked to original sources
PubMed1992

Psychophysics of arm movements and human aging.

The purpose of this study was to investigate possible age-related differences in the physical stimulus-psychological response relationship. Young and older adult subjects moved their arm to three standard locations or extents (25 cm, 50 cm, and 75 cm) on a linear positioning device. Seven standard comparison combinations were presented 20 times each. Subjects were asked to determine whether the comparison was different from the standard. Just noticeable difference, constant error, absolute constant error, and Weber ratios were calculated. In contrast to previous studies, the results clearly indicate that the physical stimulus-psychological response magnitude relationship for location and extent movements is best described by a metathetic continuum. We offer an explanation to account for the differences between location and extent movements for the just noticeable difference and Weber ratio. The failure to find differences between the age groups suggests that age-related declines cannot be generalized to all perceptual systems.

Adolescent↗
PubMed1992

Age-related differences in the control of spatial aiming movements.

The experiment was designed to (a) examine age-related differences in the control of aiming movements, and (b) determine the locus of slowing in movement execution of older adults. Fitts's (1954) index of difficulty (ID) was used to manipulate movement execution demands, and kinematics were used to examine the response characteristics. Twelve young and 12 older adults performed simple aiming movements 10 cm or 20 cm in amplitude to targets of 0.5 cm, 1.0 cm, or 2.0 cm in width, resulting in IDs ranging from 3.32 to 6.32. The results for both young and older subjects support the prediction that movement time (MT) increases as a function of ID and that older adults are significantly slower and more affected by increases in ID than the young adults. Velocity and acceleration profiles of the older adults' movements displayed very different response characteristics than those of the young adults. The results suggest that older adults emphasize accuracy of response and are concerned with the latter phase of the movement in order to contact a target accurately.

Acceleration↗
PubMed1991

Age differences in the maintenance and restructuring of movement preparation.

In 2 experiments, elderly and young subjects performed simple reaction time, choice reaction time, and movement plan restructuring tasks, using a stimulus precuing paradigm. In Experiment 1, the precue display (200 ms) and preparation interval (250, 500, 750, or 1,000 ms) were experimentally determined. In Experiment 2, the precue display interval was subject determined. For the restructuring task, the precue specified the response on 75% of the trials, enabling movement plan preparation with respect to movement parameters of arm and direction. On remaining trials, the precue incorrectly specified the response, requiring movement plan restructuring. Elderly, but not young, subjects restructured a movement plan for direction more quickly than for arm or for both parameters. These findings indicate that elderly individuals have poorer movement plan maintenance for direction than for arm and thus exhibit functional change in movement preparation processes relative to young individuals.

Adult↗
PubMed1988

Aging and the restructuring of precued movements.

A precue paradigm was used to examine the time it takes to restructure a planned motor response. Two groups of subjects, a young group and an elderly group, performed an aiming task in which 75% of the trials involved no change of movement parameters. On remaining trials, subjects had to change one or more of the movement parameters. Elderly subjects had slower reaction times (RTs), movement times, and made more errors in both conditions. Elderly subjects had proportionally longer RTs overall, independent of restructuring a movement plan. Preparation of arm and direction also exhibited a proportional increase in RT. However, differential aging effects were found for preparation of extent. Elderly subjects were slower preparing short movements compared with long movements, whereas young subjects showed the opposite trend. These results suggest that with advancing age, operations concerned with movement-plan restructuring for arm and direction undergo change in processing rate, whereas operations for extent undergo more extensive alteration.

Adult↗
PubMed1988

Age differences in bimanual coordination.

A bimanual coordination experiment was conducted in which two groups of 10 male and female participants, elderly (67 to 75 years of age) and young (21 to 25 years of age), produced unimanual, bimanual symmetrical (equal extent amplitude), and bimanual asymmetrical (unequal extent amplitude) movements. In addition to an overall increase in performance latency, the elderly group exhibited a linear increase in response initiation (RT) with increases in task complexity similar to that of the young group. However, the elderly participants showed a proportional increase over the young participants in response execution latency (MT). Further, the elderly group had a slower RT for short movements than long movements, an effect not found in the young group. Compared with the young participants, the elderly participants showed greater asynchrony in response initiation of bimanual movements; increased inability to subsequently compensate during response execution also resulted in a greater asynchrony in response termination. These results suggest specific aging deficits in bimanual coordination processes.

Adult↗
PubMedDate not supplied

Movement specification time with age.

An experiment is reported which localizes and compares movement specification times between three age groups, young (18-25 yrs.), middle (40-50 yrs.), and elderly (65-75 yrs.), in order to assess whether movement planning processes are partially responsible for the commonly observed slowing of response initiation time in the elderly. A movement precuing paradigm was used in which 24 subjects (8/age group) received either no, partial, or complete movement task information prior to the imperative response signal. The results established that the elderly had slower reaction times, movement times, information transmission rates and more errors. While the results indicated that the elderly could use precue information to prepare an upcoming movement, their specification times for arm, direction, and extent were markedly slower. The data are interpreted as providing evidence that part of the slowing in reaction time observed in the elderly is due to the increased time required to specify a dimension of movement.

Adolescent↗