Abortion, embryonic stem cell research, and waste

Can one consistently deny the permissibility of abortion while endorsing the killing of human embryos for the sake of stem cell research? The question is not trivial; for even if one accepts that abortion is prima facie wrong in all cases, there are significant differences with many of the embryos used for stem cell research from those involved in abortion—most prominently, many have been abandoned in vitro, and appear to have no reasonably likely meaningful future. On these grounds one might think to maintain a strong position against abortion but endorse killing human embryos for the sake of stem cell research and its promising benefits. I will argue, however, that these differences are not decisive. Thus, one who accepts a strong view against abortion is committed to the moral impermissibility of killing human embryos for the sake of stem cell research. I do not argue for the moral standing of either abortion or the killing of embryos for stem cell research; I only argue for the relation between the two. Thus the conclusion is relevant to those with a strong view in favor of the permissibility of killing embryos for the sake of research as much as for those who may strongly oppose abortion; neither can consider their position in isolation from the other.     

Therapeutic Practices and Ethical Beliefs of Professionals Working With Adolescents in Residential Treatment

The authors investigated dual relationships between 2 groups of staff (direct care and professional) and adolescent clients in 2 residential treatment programs. Staff were surveyed on their behavior and corresponding ethical beliefs regarding interactions they believed to be acceptable with minor clients specifically at termination of the treatment program. Direct care staff were more likely than were professional staff to have inconsistencies in behaviors and ethical beliefs. The American Counseling Association's (1995) Code of Ethics would prohibit some of the staff beliefs regarding acceptable behavior. Both groups were uncertain about the ethical appropriateness of certain interactions with adolescent clients. Implications are discussed.     

Adaptive Dynamics of the Leg Movement Patterns of Human Infants: I. The Effects of Posture on Spontaneous Kicking

This is the first of two articles in which we describe how infants adapt their spontaneous leg movements to changes in posture or to elicitation of behaviors by a mechanical treadmill. In this article, we compare the kinematics of kicks produced by 3-month-old infants in three postures, supine, angled (45 degrees ), and vertical, and examine the changes in muscular and nonmuscular force contributions to limb trajectory. By manipulating posture we were able to assess the sensitivity of the nascent motor system to changes in the gravitational context. The postural manipulation elicited a distinct behavioral and dynamic effect. In the more upright postures, gravitational resistance to motion at the hip was 4 to 10 times greater than resistance met in the supine posture, necessitating larger muscle torques to drive hip flexion. Kicks produced in the vertical posture showed a reduction in hip joint range of motion and an increase in synchronous joint flexion and extension at the hip and knee. At the same time, hip and knee muscle torques were also more highly correlated in kicks performed in the vertical than in the supine or angled posture. This increased correlation between muscle torques at the hip and knee implicates anatomical and energetic constraints-the intrinsic limb dynamics-in creating coordinated limb behavior out of nonspecific muscle activations.     

Gravity constraints in infant motor development

The effect of gravity in determining if and when during infancy movements eventuate and the rate at which they develop is unknown. In accordance with intersegmental relationships (Hof, 1992), a muscle moment during infancy would have to develop more rapidly than the gravitational moment before movement could occur. In this investigation, the effect of growth through the influence of gravity on the joint moments in the axial region when infants were in a prone or supine posture was examined. A mathematical model that considers the body to be composed of transverse elliptical cylinders, 1 cm deep and of known density, was used in estimating the mass of the 16 segments of the body. The gravitational moments about 3 joints within the axial region (C7-T1, T12-L1, and the hip) were determined by summation, using the radii from the joint transverse axis to the center of mass of the segments. Infants (N = 27) aged between 9 and 36 weeks at the beginning of the study were tested monthly 6 times, and the effect of growth on the gravitational moments was represented by first-order polynomials. Age x Joint analysis of variance (ANOVA) of the mean slopes of the regressions for the gravitational moments revealed significant main effects for age and joint. The means increased monotonically with the number of segments and decreased as infants aged. The mean slopes of the neck and trunk joints were significantly smaller than that of the hip joint. With increasing age, the gravitational slope was significantly smaller. The changes in the gravitational moments during infancy are seen as likely control parameters effecting phase shifts in motor patterns during development.     

Individual and group differences in intelligence and speed of information processing

A battery of eight different reaction time (RT) tests, measuring the speed with which individuals perform various elementary cognitive processes, and a group test of scholastic aptitude (the Armed Services Vocational Aptitude Battery, ASVAB) were given to 50 black and 56 white male vocational college students. The regression of the general factor scores of the ASVAB on the RT measures yielded a shrunken multiple correlation of 0.465. Although discriminant analyses, when applied separately to the ASVAB subtests and to the RT variables, showed highly comparable overall discrimination (over 70% correct classification) between the black and white groups, factor scores derived from the general factor (labeled ‘speed of information processing’) of the RT battery show only about one-third as large a mean black-white difference as the mean group difference on the general factor scores derived from the ASVAB. Comparisons were also made between the 106 vocational college students and 100 university students of higher average academic aptitude who had previously been tested on the same RT battery (Vernon, 1983a). These groups showed marked differences on the RT variables, the largest differences occuring on the tests that required more complex cognitive processing. The more complex RT tests also correlate most highly with the psychometric measures of ability within each group. The results are consistent with the hypothesis that individual differences and the mean differences between groups in psychometric abilities and scholastic achievement are related to differences in the speed of information processing as measured in elementary cognitive tasks.     

Menstrual cycle effects on task performance examined in the context of stress research

The study examined the effects of degree of paramenstrual distress, signal frequency, task load and time on task on psychomotor performance across the menstrual cycle. Simple reaction time, choice reaction time and pursuit tracking were the tasks employed, and performance was assessed using the metrics of mean level, variability, and errors of omission and commission. The results showed performance as a function of menstrual cycle phase and paramenstrual distress to be highly task and metric specific, a finding typical of stressor variables: pursuit tracking was affected by phase, with mean performance at its worst premenstrually; choice reaction time was dependent on a complex interaction of experimental variables and measurement metrics; simple reaction time showed no significant effects. Patterns of attention allocation in a time-sharing situation combining both pursuit tracking and choice reaction time components were also investigated. Trends here indicated relatively better performance both menstrually and intermenstrually as components increased in signal/response frequency, with a corresponding deterioration premenstrually. Overall performance capacity appeared to be greatest at menstruation, and the degree of attentional selectivity was least. High distress women performed better on low frequency components, whereas asymptomatic women did better at higher signal rates.     

Reaction time,movement time,and intelligence: A replication and extension

The purpose of the investigation was to replicate and extend a study by Jensen and Munro which found reaction time (RT) and movement time (MT) parameters to correlate negatively and moderately with Raven matrices performance. A sample of 20 ninth-grade girls was used. Relationships between RT and MT and Raven scores were found to be negative and moderate to high, thus replicating the Jensen and Munro study. In addition, moderate to strong negative correlations were found between RT and MT parameters and reading comprehension and performance on the California Test of Basic Skills. Weaker relationships were found for mathematics and English grades although the direction was consistently negative.     

Critical flicker frequency and intelligence

Tests of verbal intelligence (Concept Mastery Test) and nonverbal intelligence (Raven's Advanced Progressive Matrices) showed nonsignificant zero-order correlations and a nonsignificant multiple correlation with critical flicker frequency (CFF), in 100 university students. Age-partialled correlations were even lower, and corrections for attenuation and restriction of range yielded unimpressive results. It was concluded that CFF has a negligible relationship to psychometric intelligence and is probably a poor tool in the investigation of the nature of g.     

Who's Up First? Testing for Order Effects in Structured Interviews Using a Counterbalanced Experimental Design

A growing body of research suggests that, apart from the wording of specific questions, various aspects of the interview process itself may affect the reliability of information provided by research participants. To examine whether the order of presentation of specific diagnostic modules affects the likelihood of subjects' yes/no responses within the Diagnostic Interview Schedule for Children (DISC), the authors used a counterbalanced design, presenting two DISC diagnostic modules to children and their parents in standard or reversed order. Results indicate that the order of module administration exerts effects on the total numbers of symptoms endorsed, level of impairment, and the likelihood of meeting diagnostic criteria, regardless of whether the information is provided by parent or child respondents. Future child and adult assessment measures should take these difficulties fully into account through novel approaches to instrument design and interview procedures.     

Subject and Interview Characteristics Affecting Reliability of the Diagnostic Interview Schedule for Children

Despite the well-known difficulties in obtaining reliable and valid assessments of child psychopathology, investigators generally have not examined the influence of factors such as subject characteristics or the specific assessment procedures themselves on the validity of the information obtained. To address these issues, this special section presents four studies of the Diagnostic Interview Schedule for Children, in which investigators examined the impact of a range of variables on the reliability of its symptom and diagnostic information. Factors studied include interview structural characteristics; question length, complexity, and placement within the interview; and interview subject characteristics. Overall findings suggest that interview and subject characteristics exert important influences on the data obtained, and that novel approaches, such as allowing subjects a greater role in the ordering of questions to be answered, may improve the precision and accuracy of such measures of children's psychopathology.