Advance directives and the personal identity problem

The value and authority of advance directives such as the living will and the durable power of attorney are discussed, as well as the dangers of loss of personal identity and psychological continuity that these directives present. Differing theories of the degree of psychological continuity necessary for the preservation of personal identity are examined, concluding with the author's "compromise position" that cases of permanent unconsciousness and neurological dementia destroy some of the preconditions for personhood and thereby negate the choice between respecting the wishes of the formerly competent person and the new, different person's life because such beings are not persons at all.     

The acquisition of spatial knowledge under conditions of temporospatial discontinuity

Summary Three experiments were conducted to examine the effect of temporospatial discontinuity on route learning. Discontinuity was created by showing subjects in a route-learning task a set of environmental scenes comprising a route in scrambled, rather than logically sequenced, order. Results from Experiments 1 and 2 indicated that discontinuity during learning affected the accuracy and the quantity of the route knowledge acquired, but suggested that the processes underlying acquisition were relatively robust. Results from Experiment 3 suggested that learning routes under conditions of discontinuity leads to a greater exaggeration of distance between route segments than is the case without discontinuity.     

Improving aerobic capacity in healthy older adults does not necessarily lead to improved cognitive performance

The effects of aerobic exercise training in a sample of 85 older adults were investigated. Ss were assigned randomly to either an aerobic exercise group, a nonaerobic exercise (yoga) group, or a waiting-list control group. Following 16 weeks of the group-specific protocol, all of the older Ss received 16 weeks of aerobic exercise training. The older adults demonstrated a significant increase in aerobic capacity (cardiorespiratory fitness). Performance on reaction-time tests of attention and memory retrieval was slower for the older adults than for a comparison group of 24 young adults, and there was no improvement in the older adults' performance on these tests as a function of aerobic exercise training. Results suggest that exercise-related changes in older adults' cognitive performance are due either to extended periods of training or to cohort differences between physically active and sedentary individuals.     

Effect of distance instructions on size judgments

The proposition that in a reduced-cue setting subjects could use cognitive information about an object's distance to make accurate judgments of its size was tested. An improved paradigm was used to determine the effects of distance instructions per se. This paradigm also allowed independent tests of the effectiveness of cue reduction. The data indicated that cue reduction was successful and that the specific distance tendency governed size judgments when there were no distance instructions. When distance instructions were given, they produced size judgments in precisely the ratio predicted by the size-distance invariance hypothesis. However, there was a large constant error, which reflects a tendency of college students to overestimate the amount of distance signified by a verbal instruction. Hence, cognitive information in the form of verbal distance instructions has precise effects on size judgments, but the latter are not veridical, even in the absence of anchor effects from the specific distance tendency and residual perceptual cues.     

Eliminating selective stimulus control: a comparison of two procedures for teaching mentally retarded children to respond to compound stimuli

Selective stimulus control occurs when behavior fails to come under control of all characteristics of a compound stimulus after discrimination training. Two different assessment procedures, one used in prior research and the other incorporating incorrect stimuli (S - 's) which differed minimally from the correct stimulus (S+), were used to detect stimulus control deficits characteristic of selective stimulus control. The efficacy of two training procedures in eliminating selective stimulus control observed with three trainable mentally retarded children was evaluated in Experiment 1. A training procedure using S - 's that were minimally different from the S+ was designed to reduce the probability that stimulus discriminations could be based on stimulus characteristics other than experimenter-specified characteristics defining the S+. This procedure proved more effective in preventing and eliminating selective stimulus control as measured by both assessment procedures than an alternate discrimination training procedure that failed to impact the more stringent measures of selective stimulus control. Experiment 2 indicated that these improvements in stimulus control were not a function of varying degrees of difficulty between stimulus sets or of a prior history of discrimination training with the less effective training procedure. The need for better assessment procedures to detect selective stimulus control and suggestions for further improvements in discrimination training procedures are discussed.     

Peer relationships in ADDH and normal children: A developmental analysis of peer and teacher ratings

Peer and teacher perceptions of younger and older ADDH and normal children were compared. Peer nominations on the Pupil Evaluation Inventory revealed that ADDH children received more nominations on the Aggression factor and fewer on the Likability factor. ADDH boys received more nominations on the Withdrawal factor. Generally, older children received fewer nominations, but age did not interact with diagnosis; that is, younger and older ADDH children were perceived by peers as equally deviant. Discriminant analyses showed that peer ratings were useful in discriminating between ADDH and normal boys, but not between ADDH and normal girls. Teacher ratings of peer behavior suggested that older ADDH girls were perceived as less disturbed than younger girls. However, teacher ratings of boys revealed no age by diagnosis interactions. Low to moderate correlations were found between peer and teacher ratings of ADDH boys, and the pattern of relationship varied with age.During the writing of this report, Charlotte Johnston was supported by a Sir James Lougheed Fellowship, Alberta Heritage Scholarship Fund.     

Religion and children with disabilities

Religion as a personal coping resource used by parents of infants and toddlers with disabilities has received some attention in recent literature. This exploratory study involved indepth interviews of 12 parents who had children with disabilities ranging in age from 15 months to 30 years. The ways in which religion can be used as a coping resource across the life-cycle are exemplified through excerpts from these interviews. Prayer, church attendance, and specific religious beliefs were identified as sources of support which helped some parents feel a growing sense of hope and strength. Suggestions for future research are discussed.Tess Bennett, Ph.D., is Assistant Professor in the University of Illinois College of Education, Department of Special Education; Deborah A. Deluca, B.A., is in the Department of Educational Psychology, and Robin W. Allen, M.S.W., is a doctoral candidate in the Department of Social Work at the same university.     

Genetic counseling after abnormal prenatal diagnosis: Facilitating coping in families who continue their pregnancies

Families continuing a pregnancy after abnormal prenatal diagnosis face a unique crisis. Case examples are combined with clinical observations and a review of selected literature to define the elements of this crisis. Counseling strategies are discussed that may facilitate coping. Further research is needed to define the experience, as well as to identify effective coping strategies and successful counseling approaches.     

Combining image degradations in a recognition task

Six experiments are reported that investigate the effect on form recognition performance of combining three kinds of stimulus degradations: local area averaging of intensities, low-pass spatial frequency filtering, and random dot visual interference. The effects are shown to be more complicated than previously reported in simple demonstrations. The complexity of the results suggests that models based on single stimulus attributes such as energy or spatial frequency spectrum probably cannot account for the data. Eclectic theories that invoke combinations of redundant processes may be necessary for describing visual recognition phenomena, even within the limited domain examined in this study.