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D W Kline

Publications and source records attributed to D W Kline.

At least 19 recordsLinked to original sources
PubMed1993

Self-reported hearing problems in daily life throughout adulthood.

The authors assessed age differences on self-reported hearing problems on the performance of auditory tasks in the natural environment. The Your Hearing questionnaire was administered to 265 respondents (aged 20-94 years). Both the degree and variability of self-reported hearing problems were found to increase significantly with age, including those associated with listening to speech under conditions of background noise, the perception of normal and distorted speech, and the perception of short segments of speech and the perception of high-pitched sounds. Experienced hearing problems were greater for Ss who judged their hearing as being of poor quality. Findings suggest that self-report measures can provide valuable insights into the impact of age-related hearing disability on daily life that are not provided by more traditional laboratory-based studies.

Activities of Daily Living↗
PubMed1992

Vision, aging, and driving: the problems of older drivers.

Although there are well-recognized declines in visual functioning with age, their contribution to the problems of older persons on tasks in the natural environment, including driving, are largely unknown. Adults ranging in age from 22-92 years were surveyed in regard to their visual difficulties when driving and performing everyday tasks. The visual problems of drivers increased with age along five different visual dimensions: unexpected vehicles, vehicle speed, dim displays, windshield problems, and sign reading. Several of the age-related visual problems that were reported appear to be related to the types of automobile accidents more common among older drivers. The study also replicated the findings from an earlier investigation of non-driving tasks that showed visual declines with age on five dimensions: visual processing speed, light sensitivity, dynamic vision, near vision and visual search. These findings indicate promising areas of research regarding the effects of visual aging on tasks in the natural environment.

Adult↗
PubMed1990

Self-reported visual problems of older drivers.

We conducted a survey in order to gain insights into the reasons older persons decide to give up driving. Our survey focused on vision. We probed the relationship between visual deficiencies and driving status by asking older people about the problems they encountered while performing routine visual tasks. The results showed that older persons who had recently given up driving reported more visual problems than did their driving counterparts. These problems related to difficulties in dynamic vision, visual processing speed, visual search, light sensitivity, and near vision. The results suggested that older persons are sensitive to their own visual deficits and that this awareness influences decisions about driving.

Activities of Daily Living↗
PubMed1990

Visibility distance of highway signs among young, middle-aged, and older observers: icons are better than text.

The visibility distances for young, middle-aged, and elderly observers of text and icon versions of four different highway signs were compared under day and dusk lighting conditions. No age differences were observed. Icon signs, however, were visible at much greater distances than were text signs for all three age groups, a difference that was more pronounced under dusk conditions. There were no age differences in the comprehension of icon signs, but there was considerable variability from one icon sign to another in the degree to which they were comprehended. Acuity was found to be a better predictor of the visibility distance of text signs in both day and dusk conditions than it was of icon signs. To the degree that they are comprehended, icon signs appear to offer drivers of all ages almost twice as much time in which to respond to them.

Adult↗
PubMed1988

Effects of noise type and retinal eccentricity on age differences in identification and localization.

Twenty young (M = 24 yrs), and 20 older adults (M = 62 yrs) identified and localized two target letters presented nonfoveally in each of three noise conditions. Targets were presented in isolation, embedded in featurally similar distractors, or embedded in distractors that were featurally similar to the alternate response. Older adults were generally slower to identify targets, particularly in multi-element arrays. Age differences favoring the elderly were found in target-similar identification accuracy, but the young identified targets more accurately in alternate-similar noise. Localization errors were greater among the elderly, who exhibited a bias to localize targets to central array positions. Age differences in noise effects are explained as resulting from ontogenic change in the duration of temporal integration required to encode arrays to the level of a primary detection response (Estes, 1982). The model's predictions were given small-scale validation when visibility was decreased in young adults who then produced performance profiles similar to the elderly.

Adult↗
PubMed1987

Age differences in target identification as a function of retinal location and noise level: examination of the useful field of view.

Foveal and peripheral target detection were compared in young adults (M age = 22 years) and older adults (M age = 66 years) who were optically corrected for the viewing distance. In a two-alternative, forced-choice task, target letters were presented at 0 degree to 10.5 degrees from fixation. Targets were presented alone, flanked on each side by one noise element (i.e., nontarget letter), or embedded in a horizontal row of 19 noise elements. An Age X Noise Level X Location interaction was obtained, wherein age differences were largest for peripheral targets presented in noise. Slope analyses of latency data showed that the performance of young adults in the high-noise condition was most similar to that of older adults in the low-noise condition. At the functional level, results indicated that aging is associated with a restricted useful field of view. In addition, the data suggest that age differences in search can be described by a model in which older adults take smaller perceptual samples from the visual scene and scan these samples more slowly than do the young adults.

Adult↗
PubMed1987

Ageing and the spatiotemporal discrimination performance of the visual system.

Visual ageing is generally associated with a decline in spatial vision for stationary stimuli, especially those which are of high spatial frequency. Some, but probably not all of this loss can be attributed to apparently normal age-related changes in the ocular media that attenuate and scatter incident light. The loss in the temporal resolving capacity of the senescent visual system is even more prominent and appears to be due almost completely to neural mechanisms, including alterations in the functioning of both the 'transient' and 'sustained' types of visual channel. The losses with age in both spatial and temporal vision are highly consistent with the type and degree of visual problems elderly persons report that they experience in carrying out daily tasks. Further research will be needed to determine the mechanisms which underlie these changes as well as to determine the degree to which they can be remedied.

Activities of Daily Living↗
PubMed1983

Age, the eye, and the visual channels: contrast sensitivity and response speed.

Age differences in spatial vision were examined by establishing contrast sensitivity functions for young and old adults. In addition, differences in the speed of operation of the different visual channels and their contribution to age differences in reaction time were assessed in a comparison of response speed to sinusoidal gratings of varied spatial frequency. An age-related loss in contrast sensitivity was observed primarily for stimuli of intermediate and high spatial frequency, an effect apparently due mostly to age-related optical differences. Reaction time varied markedly as a function of spatial frequency for the older participants, an outcome only partly attributable to age differences in target visibility. These data indicate a slowing in the speed of operations of individual visual channels and/or a change in the relationship between visual channel classes. These findings also raise a question in regard to the meaning and comparability of any studies that have used measures of response latency to the figural aspects of stimuli.

Adolescent↗
PubMed1982

Age and temporal resolution in color vision: When do red and green make yellow?

The ability to temporally resolve color stimuli was compared in young and old adults. Stimuli consisted of pairs of brief green and red flashes separated by six levels of interstimulus interval and presented at two different luminance levels. Integration of the color pairs to produce reports of yellow decreased significantly with increasing interstimulus interval, particularly for the younger group. This difference remained when the age-related loss in retinal illumination was compensated by increased stimulus luminance. These data indicate a decline with age in temporal resolution in color vision. Further, they suggest that age differences in temporal resolution can be more appropriately attributed to age-related differences in visual/neural mechanisms than to changes in the ocular media or photoreceptor activity.

Adult↗
PubMed1981

What are the age differences in visual sensory memory?

The present investigation examined age differences in visual persistence using a direct measurement technique of Haber and Standing (1969). Young and old adult subjects were compared as to the apparent continuity of a circle when it was alternated cyclically with a second blank interstimulus field of variable duration. Contrary to a previous study, old subjects demonstrated significantly greater levels of persistence. Contrast relationship of the target stimulus and its background did not interact with age. Although the data were consistent with a hypothesis of increased persistence of stimuli in the senescent nervous system, alternatively they suggest problems in the direct measurement technique.

Adolescent↗
PubMed1980

Age and the identification of inconspicuous words.

The purpose of these experiments was to examine systematically the basis for the profound inability of healthy, well-educated older subjects in earlier research to identify inconspicuous words. Two experiments were carried out in which inconspicuous words were formed of regular block letters composed in a black-on-white (Experiment 1) or a white-on-black format (Experiment 2). In both experiments the performance of the older persons was nonsignificantly below that of the younger subjects (an effect which reached significance when considered across the two experiments together). No effects were observed for contrast relationship or for a remediation of age deficits in inconspicuous word identification through interposed reversible figure training. The results suggest strongly that, for older persons, inconspicuous word identification is highly dependent upon the specific structural composition of the stimuli and is consequently explicable in terms of the already well-documented changes in perceptual function with age.

Adolescent↗
PubMed1980

Metronome pacing and age: the effect of irrelevant stimuli.

Community resident and institutionalized elderly were compared with young subjects in their ability to ignore task-irrelevant stimuli in a time estimation task. Production and reproduction estimates were compared under three metronome conditions: no metronome, 40 beats per minute (bpm), and 80 bpm. The no-metronome estimates of both old groups were significantly shorter and more accurate than those of the young subjects; estimates were more accurate with the reproduction than with the production method. A significant "metronome driving" effect was seen in the estimates of the two old groups, especially the institutionalized one. The results are consistent with an increase in perceptual noise with age and also suggest that the social conformity of older persons and their susceptibility to irrelevant stimuli can be represented as an increase in field dependence with age.

Acoustic Stimulation↗
PubMed1980

The estimation of short time intervals as a function of age and metronome pacing.

The accuracy of estimation of short time intervals was studied in old institutionalized and young college male and female participants as a function of three levels of audible background metronome rate (0, 40 and 90 beats/min). The main effects of metronome and interval length, as well as the age by metronome rate interaction, were significant. Unlike the young participants, the time judgments of the older participants were significantly and systematically determined by metronome rate. These results are consistent with the notion of increased field-dependence among older persons and suggest that their greater social conformity and their inability to ignore irrelevant stimuli might also be explicable in the same theoretical terms.

Acoustic Stimulation↗
PubMed1978

Stimulus persistence in CFF: overarousal or underactivation?

The physiological basis of hypothesized adult age increases in the persistence of stimuli was studied in 16 young (X age 19.1 years) and 16 old (X age 70.1 years) male and female subjects. Changes in CFF threshold and skin conductance were measured as a function of loud white noise activation and artificial pupil. CFF was significantly lower in the old group and with artificial pupil in both age groups. Significant effects were also found for activation x sex and activation x age x sex. Skin conductance change was significant for activation, activation x sex, artificial pupil x age, artificial pupil x order and artificial pupil x order x activation. The results were interpreted as supporting an overarousal basis of an age increase in stimulus persistence.

Adolescent↗
PubMed1978

Examination of stimulus persistence as the basis for superior visual identification performance among older adults.

Visual identification performance of sequentially presented corresponding word-halves was studied in 12 young (mean 18.9 years, range 18-21) and 12 old (mean 68.0 years, range 59-78) male and female subjects. Corresponding word-halves were composed of straight horizontal and vertical line segments and when superimposed tachistoscopically formed clear, fully closed 3-letter words. Stimulus duration and interstimulus interval (ISI) were systematically varied. Correct word recognition was found to be an inverse function of ISI and stimulus duration for both young and old subjects. An interaction was found between age, sex, and stimulus duration. Recognition scores were significantly higher among older subjects, an effect which was particularly prominent at greater ISIs. The data offer strong support for the stimulus-persistence model as applied to age differences in the sequential integration of form.

Adolescent↗
PubMed1977

Persistence of complementary afterimages as a function of adult age and exposure duration.

The persistence of complementary afterimages was studied in 36 young (X age 18.8 years) and old (X age 62.1 years) male and female subjects. Afterimage persistence was found to be a direct function of exposure duration and to be greater for the older subjects as compared with the younger ones. The interactions between age and duration and between presentation order and duration were also significant. The data extend support for the "stimulus persistence" model to age differences in retinal function.

Adolescent↗