Conflicting social paradigms of human freedom and the problem of justification

In recent work, Rawls, Nozick, and the ‘democratic‐socialist’ theory of Markovi? and Gould, attempt to ground rival models of just economic relations on the basis of conflicting interpretations of human freedom. Beginning with a philosophical conception of humans as essentially free beings, each derives a different system of basic rights and freedoms: (1) the familiar democratic civil and political rights of citizenship in the West (Rawls); (2) the classical bourgeois market freedoms ‐ ‘life, liberty, and property’ (Nozick); and (3) democratic socialist rights of self‐management of the work‐place (Gould and Markovi?). I argue that each of these theorists implicitly assumes a different but ungrounded ’social paradigm of human agency’ concerning the particular forms of human choice which are singled out as most important for a free, human life. None of these theories contains the methodological resources for showing why the forms of human agency it ‘emancipates’ are more important than the forms it suppresses or ignores. In order to overcome this impasse and provide a way of evaluating such rival paradigms of free agency, I elaborate a methodology based on the idea that a free society must provide its members with ‘equality in the social bases of self‐respect’. I use this methodology to argue that all three of the above conceptions are blind to problems of human agency, freedom, and dignity posed by the modern phenomena of welfare dependency, unemployment, and a self‐stultifying division of labor.     

The Treatment of Hard-Core Voluntary Drug Addict Patients

The complete population of adolescents in a residential and day-treatment program over a 4-year period, 532 youths, served in two studies. Along with residential and day-treatment settings, predictive variables of interest were the number of hours spent in group, individual, and family therapy. A total of 227 adolescents qualified for Study 1 which found a reduction of rates of criminal charges from pre- to posttreatment. Study 1 also found that hours in group therapy explained the most variance in the reduction in rates of criminal charges, followed closely by hours in individual therapy. Hours in family therapy was not a significant predictor. A total of 430 adolescents qualified for Study 2, which found that residential treatment was associated with greater reductions in adult correctional commitments than day treatment. Implications stress the need for further research examining the relationships between therapeutic components of residential treatment and behavioral outcomes.     

Patterns of Aggression in Parents and their Children

In this research, we examined children's awareness of inconsistencies in messages that are meaningful for children, instructions for games. In the first experiment, kindergarten (n = 25) and second- (n = 25) and fourth-grade (n = 26) children were individually read the instructions for two games, each of which included two inconsistent statements. Chi-square analyses yielded a significant effect for grade for one game (p < .05) and a marginally significant effect for a second game (p < .10). In a second experiment, second- (n = 40), fourth- (n = 40), and sixth-grade (n = 40) children were read the instructions for two games, each of which included two statements that were inconsistent. An analysis of variance demonstrated that with an increase in grade, there was a significant increase (p < .001) in awareness that a message contained an inconsistency. The analysis also indicated that the subjects were more willing (p < .08) to question an adult than they were to question a child about an inconsistency. Moreover, a regression analysis indicated that awareness of inconsistencies in the rules for games was significantly related to memory (p < .001) and to one's ability to note inconsistencies in shorter, simpler messages (p < .001).     

Effect of Age and Gender in the Control of Elbow Flexion Movements

In previous studies of rapid elbow movements in young healthy men, characteristic task-dependent changes in the patterns of muscle activation when movement speed or distance was varied have been reported. In the present study, the authors investigated whether age or gender is associated with changes in the patterns of muscle activity previously reported in young men. Arm movements of 10 healthy older and 10 healthy younger participants (5 men and 5 women in each group) were studied. Surface electromyograms (EMGs) from agonist (biceps) and antagonist (triceps) muscles, kinematic and kinetic parameters, as well as anthropometric and strength measures were recorded. All 4 groups of participants showed similar task- (distance or speed) dependent changes in biphasic EMG activity. Similar modulation of the initial rate of rise of the EMG, integrated agonist and antagonist EMG activity, as well as their relative timing were observed in all 4 groups. Those results suggest that older individuals of both genders retain the control strategies for elbow movements used by young individuals. Despite the qualitative similarities in the patterns of muscle activation, the men moved more quickly than the women, and younger participants moved more quickly than older participants. Those performance differences could not be explained in terms of differences in body size and strength alone.     

Specificity of Task Constraints and Effects of Visual Demonstrations and Verbal Instructions in Directing Learners' Search During Skill Acquisition

In the present study, the efficacy of visual demonstrations and verbal instructions as instructional constraints on the acquisition of movement coordination was investigated. Fifteen participants performed an aiming task on 100 acquisition and 20 retention trials, under 1 of 3 conditions: a modeling group (MG), a verbally directed group (VDG), and a control group (CG). The MG observed a model intermittently throughout acquisition, whereas the VDG was verbally instructed to use the model's movement pattern. Participants in the CG received neither form of instruction. Kinematic analysis revealed that compared with verbal instructions or no instructions, visual demonstrations significantly improved participants' approximation of the model's coordination pattern. No differences were found in movement outcomes. Coordination data supported the visual perception perspective on observational learning, whereas outcome data suggested that the modeling effect is mainly a function of task constraints, that is, the novelty of a movement pattern.     

Spinal Cord Circuits

Over the past decade, research at three different levels of sensorimotor control has revealed a degree of complexity that challenges traditional hypotheses regarding servocontrol of individual muscles: (a) The connectivity of spinal circuits is much more divergent and convergent than expected. (b) The normal and reflex-induced recruitment of individual muscles and compartments of muscles is more finely controlled than was noted previously. (c) The mechanical interactions among linked skeletal segments and their often multiarticular muscles are neither simple nor intuitively obvious. We have developed a mathematical model of the cat hind limb that permits us to examine the influence of individual muscles on posture and gait. We have used linear quadratic control theory to predict the optimal distribution of feedback from a hypothetical set of proprioceptors, given different assumptions about the behavioral goals of the animal. The changes in these predictions that result from changes in the structure and control objectives of the model may provide insights into the functions actually performed by the various circuits in the spinal cord.     

The Effect of Interpolated Motor Activity on the Short-Term Retention of Movement Distance and End-Location

The effect of an interpolated movement on the recall of a blind, lever-positioning movement was assessed separately for the reproduction cues of distance and end-location. Both cues showed the context effect of assimilation, that is, the end-location of the interpolated movement caused directional biasing of the algebraic or constant error (CE) for location reproduction while the length of the interpolated movement caused similar directional biasing for distance reproduction. Variability about algebraic error (VE) was used to assess forgetting. There was no change in VE for location reproduction, and an increase in VE for distance reproduction was limited to the relatively large movements. Thus, an interpolated movement that does not have to be remembered does not cause interference with the retention of location information, but does cause some interference with the retention of distance information. The findings are discussed in relation to a model of motor short-term memory which incorporates both CE and VE.     

Comment on “Retention Characteristics of Motor Short-Term Memory Cues”

Marteniuk (1973) used negative results, which may be attributed to a lack of power, to question the adequacy of variable error as a measure of forgetting. He also used these negative results, along with constant error results which were consistent with the Laabs (1971, 1973) model of motor memory, to reject parts of the model related to variable error. Caution is advised when interpreting negative results and interchanging dependent measures.     

Power Spectral Density Analysis of Lateral Human Standing Sway

A number of investigators have used power spectral density (PSD) analysis to try to identify and quantify various sensory systems which are involved in upright standing. Using PSD analysis, over a frequency range from 0.02-2.5 Hz, the present study examined two trials of lateral sway in each of 80 men. The results showed that little change occurred in PSD values between the first and second trials. Exponential curves were fit to the averaged trials data of each subject. The values of the parameter estimates obtained from the curve-fitting were regressed on the values of various direct, and derived anthropometric variables to try to explain the variance of the parameter estimates in terms of the anthropometrics. The subject’s center of gravity location accounted for no more than 15.8% of the parameter variance, whereas the remaining anthropometrics explained even less. The overall averaged data suggest that three functions (related to visual, vestibular, and proprioceptive processes) may underlie the sway pattern over this frequency range. PSD curves of individuals with a history of high-level athletic activity clearly differed from those of sedentary subjects.