Goal-performance relations: The effects of initial task complexity and task practice

The current study was conducted to examine the effects of task complexity and task practice (trials) on the goal-performance relationship. Specific, difficult goal assignments were predicted to enhance performance on a complex task only in later task practice. On a simpler task, specific, difficult goal assignments were predicted to enhance performance in early task practice and to disrupt performance in later task practice. The results indicated that goals exerted the predicted effects in the simple task version but had no effect in the complex task version. Possible relationships between amount of task practice and stages of skill acquisition are discussed for tasks differing in complexity. The results are also discussed in terms of cognitive resource demands and self-regulatory processes. Implications for the effectiveness of goals in relation to task complexity and task trials are also discussed.This article is based on the senior author's dissertation at the University of Minnesota. We thank Milt Hakel, Allan Jones, and Bart Osburn for their helpful comments on earlier drafts. The authors also wish to thank Phil Ackerman and John Campbell for their insightful comments throughout the research project and other members of the dissertation committee: Rich Arvey, Mark Davisson, and Marvin Dunnette.This research was partially supported by the Air Force Office of Scientific Research Project LAMP, under the auspices of the Air Force Human Resources Laboratory (contract AFOSR-87-0234) and by a Research Initiation Grant from the University of Houston.Portions of this data were presented at the American Psychological Association Meetings, Atlanta, 1988.     

Quantitative and qualitative analyses of clock drawings in Alzheimer's and Huntington's disease.

Although visuoconstructive impairment has been reported in both Alzheimer's (DAT) and Huntington's (HD) disease, there is little knowledge concerning how this cognitive deficit differs quantitatively and qualitatively in these two progressive dementias. To address this issue, the present study compared performances on the Clock Drawing Test (CDT: command and copy) of 25 DAT patients, 25 equally demented HD patients, and 25 elderly normal controls (NC). In the command condition, both patients groups were significantly impaired compared to the NC group. Although there was no significant difference between DAT and HD patients' total quantitative scores, a qualitative error analysis revealed a number of dissociations between the two patient groups. Graphic difficulties, very common in HD patients, were virtually absent in DAT patients; in contrast, conceptual errors were almost exclusively seen in DAT patients and were related to the severity of their dementia. Perseveration and "stimulus-bound" responses were also more frequent in DAT patients, and both groups made visuospatial errors. In the copy condition, the DAT, but not the HD, patients evidenced a marked improvement in performance. These results indicate that while both DAT and HD patients have significant visuoconstructive difficulties even in the early stages of their disorders, the specific cognitive processes underlying their quantitative impairments are quite different. It is possible that the DAT patients' conceptual errors are yet another indicator of the deterioration of their semantic knowledge.     

On the Relation Between Time Perception and the Timing of Motor Action: Evidence for a Temporal Oscillator Controlling the Timing of Movement

Studies of time estimation have provided evidence that human time perception is determined by an internal clock containing a temporal oscillator and have also provided estimates of the frequency of this oscillator (Treisman, Faulkner, Naish, & Brogan, 1992; Treisman & Brogan, 1992). These estimates were based on the observation that when the intervals to be estimated are accompanied by auditory clicks that recur at certain critical rates, perturbations in time estimation occur. To test the hypothesis that the mechanisms that underlie the perception of time and those that control the timing of motor performance are similar, analogous experiments were performed on motor timing, with the object of seeing whether evidence for a clock would be obtained and if so whether its properties resemble those of the time perception clock. The prediction was made that perturbations in motor timing would be seen at the same or similar critical auditory click rates. The experiments examined choice reaction time and typing. The results support the hypothesis that a temporal oscillator paces motor performance and that this oscillator is similar to the oscillator underlying time perception. They also provide an estimate of the characteristic frequency of the oscillator.     

Environmental factors in suicide in long-term care facilities.

One major purpose of this study was to identify environmental factors related to suicide in long-term care facilities. Questionnaires were mailed to a random sample of administrators at 1,080 facilities. Information was collected on facility characteristics, overt suicide, and intentional life-threatening behavior. Chi-square analyses revealed 4 environmental characteristics related to suicidal behavior and deaths from suicide: staff turnover, size, auspices, and per diem cost. More suicides occurred in larger facilities and facilities with higher staff turnover. Religious or "other" facilities experienced more suicidal deaths than public or private facilities; facilities charging less experienced more deaths.     

Factors related to sleep quality in healthy elderly women.

Elderly women in subjectively good health--free of acute illness and major sleep pathologies--who were self-identified as good (n = 22) and poor (n = 16) sleepers were compared on measures of physical health, psychological symptoms, psychosocial status, and life-style. Poor sleepers reported longer sleep latencies, less total sleep time, more nonrestorative sleep, and more daytime fatigue than did good sleepers. Sleep recordings confirmed subjective reports, with shorter total sleep times and trends for lower sleep efficiency, longer sleep latencies, and more wake-after-sleep onset among women with subjective poor sleep. Poor sleepers also were more frequent users of sedative-hypnotic medications in the past. Current medication use, alcohol and caffeine use, daytime napping, and exercise were equivalent in both groups. Psychosocial status failed to discriminate groups. Poor sleepers reported significantly more psychological symptoms than did good sleepers. The levels of both psychological symptoms and sleep disturbance were mild.