An assessment of decision-making as a possible factor in the age-related loss of contrast sensitivity

The possibility that changes in decision-making may contribute to the age-related decline in contrast sensitivity has been investigated in nineteen young subjects (ages 21-38 years) and twenty-seven old subjects (ages 55-92 years). A signal detection paradigm was employed in which the detection of stationary sinusoidal grating patterns was measured at 3 and 15 cycles deg-1 for a range of contrasts which were psychophysically equivalent for each subject. A decline in contrast sensitivity with age at the spatial frequencies studied was confirmed for contrast thresholds obtained both by the ascending method and from the 50% hit rate for detection of the grating pattern. The criterion adopted for decision-making, expressed as both beta and percentage bias, did not change significantly between young and old subjects at 15 cycles deg-1. At 3 cycles deg-1, criterion beta did not change significantly at X0.8, X1.0, or X1.2 contrast threshold, but at contrast giving 50% hit rate there was a significant increase with age. The percentage bias increased significantly at contrast threshold but not at 50% hit rate. It is inferred from the results that the loss of contrast sensitivity was not accountable in terms of the adoption of a more conservative criterion by older subjects. Hence visual loss in ageing is attributed to changes within the visual pathway rather than within higher decision-making centres.     

Relationship of physicians' nonverbal communication skill to patient satisfaction, appointment noncompliance, and physician workload

A field study of 28 residents in family practice was conducted. Physicians' self-reports of empathy, self-monitoring ability, and affective communication skill as well as their objectively measured nonverbal communication skills were examined as predictors of patient satisfaction, appointment noncompliance, and physician workload (schedule density). Physicians completed the Hogan Empathy Scale, Snyder Self-Monitoring Scale, Affective Communication Test, short form of the Profile of Nonverbal Sensitivity, and a nonverbal encoding task. Patient satisfaction with communication, affective care, and technical care was assessed using a 25-item, visit-specific satisfaction scale. Appointment records were used to determine the number of patients seen by each physician and the compliance of patients with scheduled appointments. Results indicated that the three self-report measures were unrelated to the measures of patient noncompliance and patient satisfaction, but self-reported affective communication ability was significantly correlated with physician workload. Objectively measured physician sensitivity to audio communication predicted patient compliance: More sensitive physicians experienced fewer unrescheduled appointment cancellations. Nonverbal encoding skill was significantly related to patient satisfaction with affective care and to physician workload.     

Behavioral assessment of methylphenidate in a child with frontal lobe damage

The assessment and management of inattentive, hyperactive, and impulsive behavior in a 6-year-old girl who experienced frontal lobe damage are described. A multimodel approach combining medical, educational, and behavioral techniques to assess hyperactive behavior, optimal medication level, and medication and psychotherapeutic effectiveness is described. The results of the study suggest that in similar cases, children and adolescents manifesting these behaviors should be given a trial of stimulant medication in a controlled environment to assess if such therapy is indicated. Additional support is given for the increasing need for detanté and cooperation with health-care professionals.     

Dating age and stage as correlates of adolescent sexual attitudes and behavior

Dating experiences, especially the type or stage of dating, have consistently been found to be related to premarital sexual behavior. Findings regarding the age at 1st date and sexual behavior have been less consistent. This paper examined the age at which dating began and the type of dating relationship as correlates of premarital sexual attitudes and behavior among mid-teen adolescents. The analyses were based on a sample of high school students (n=836), most of whom were between the ages of 15 and 18 when the surveys were conducted. Early dating, especially early steady dating, was related to permissive attitudes and to premarital sexual experience among both males and females. The relationship between early dating and intercourse experience was particulary strong among Mormons, a religious group which has institutionalized age 16 as the legitimate age to begin dating.     

Social and solipsistic observer training: Effects on agreement with a criterion

The need to train accurate, not necessarily agreeing, observers is discussed. Intraobserver consistency as an intermediate criterion in such training is proposed and contrasted with the more familiar criterion of interobserver agreement. Videotaped observations of social interactions between handicapped and nonhandicapped preschoolers provided the medium for examining the criterion agreement of four observers trained against each type of standard. Observers generally failed to show high levels of criterion agreement whether trained to a within- or to a between-observer agreement standard. The results varied somewhat with the frequency of behaviors, however. Correlations between interobserver agreement and intraobserver consistency were variable but somewhat higher when interobserver agreement was the training criterion than when intraobserver consistency was the criterion. Correlations between interobserver agreement and criterion agreement ranged from — .16 to .89 during interobserver agreement training. Correlations between intraobserver consistency and criterion agreement ranged from — .23 to .99 during intraobserver consistency training.     

Fertility of mating in rats (Rattus norvegicus): contributions of androgen-dependent morphology and actions of the penis

Three experiments with rats (Rattus norvegicus) were conducted to examine the roles of the male's penile spines and penile cups (flaring of the distal glans) in the induction of luteal activity in the female, and in the removal of copulatory plugs from the vaginal tract. The results of Experiment 1 revealed no role for the cup in luteal induction but did suggest that elements of the ejaculatory reflex apart from cup formation contribute to the elicitation of this neuroendocrine response. The origin of this stimulatory effect was not directly determined, but indirect evidence suggested a role for penile spines. In Experiments 2 and 3, features of the glans penis that might help effect plug removal were investigated, and the experiments demonstrated that penile spines, perhaps in conjunction with penile cups, contribute to the extraction of plugs from the vagina.     

Comparative studies of squirrel monkeys (Saimiri sciureus) and titi monkeys (Callicebus moloch): performance on choice tasks in near space

Squirrel monkeys (Saimiri sciureus) and titi monkeys (Callicebus moloch) were studied in tasks involving reaching for food in near space (arm's reach). Although performance by monkeys of the two species differed in several ways familiar from previous studies, the species did not differ in the tendency to adopt a habitual position or limb during reaching. The findings contrast with previous work on spatial preferences in these species in tasks involving movement of the whole body. Together with the results of previous studies on movement patterns in these two species, the findings are placed in a comparative psychological framework of the proximate sources of use of space in nature.     

Spontaneous alternation behavior in animals: A review

Factors affecting spontaneous alternation behavior (SAB) in animals, for example, age, gender and species studied; type of apparatus and cues employed; and neuro-anatomical, neuro-chemical and motivational status of the organism, were reviewed. Despite a myriad of experiments showing interesting main effects of such variables, little research has been performed assessing the interactive affects of these factors on alternation behavior. For example, psychologists test rats in central nervous system (CNS) lesion studies, whereas psychopharmacologists tend to assess SAB in mice. Most importantly, studies have not been reported investigating the possible interactions among species, brain lesions and drugs. This is an unfortunate omission since several important alternation models include propositions relating to cholinergic and/or serotonergic coding in the hippocampus. Examination of behavioral studies revealed the primary cue for alternation among invertebrates to be body turn, whereas vertebrates rely primarily on directional and odor cues. Reference to the seeking of stimulus change remains the most compelling motivational account of why animals manifest this ubiquitious and reliable behavior pattern. This review and the unpublished studies were supported by Research Grants MH16962, MH21288, and MH36491 from the National Institute of Mental Health and the Wake Forest University Research and Publication Fund.