Laterally induced impedance effects in vision

A linear integral equation for a system of mutually impeding points is developed and solved explicitly. Particular solutions are shown to be subharmonic functions for a large class of stimuli. Specialized forms of the general equation presented in this paper occur within a number of mathematical models of Mach bands. In addition to these known spatial properties, our results also show that the time course of this basic equation may be useful in developing models of transient neural activity as well as of temporal psychophysical phenomena, such as the Broca-Sulzer effect. Further, a spatial transfer function much like the low-frequency cutoff of empirically derived modulation transfer functions follows directly from our basic integral equation if the additional assumption of spatial homogeneity is imposed.     

Individualized behavior therapy for alcoholics: a third year independent double-blind follow-up.

An independently conducted double-blind study providing third year follow-up data for 53 of 70 male alcoholics who served as subjects in an experiment evaluating “Individualized Behavior Therapy (IBT)” techniques is reported. In the original study, subjects were initially assigned to either a controlled drinking or non-drinking (abstinence) treatment goal, and were then randomly assigned to either an experimental group receiving IBT or a control group receiving conventional state hospital treatment oriented towards abstinence. Previously reported results showed that IBT subjects functioned significantly better than control subjects throughout the first year of follow-up. Second year follow-up results found that IBT subjects treated with a controlled drinking goal functioned significantly better than their respective control subjects on a variety of measures, including drinking behavior. Differences between IBT subjects treated with a non-drinking goal and their control subjects did not retain statistical significance during the second year of follow-up. The independently determined follow-up data showed that during the third post-treatment year, subjects in the experimental groups generally functioned better than their respective control subjects. Comparison of the controlled drinking experimental group with its control group showed the significantly better functioning of subjects in the experimental condition on a number of drinking and other life functioning measures. Comparison of the non-drinking groups indicated only one possible difference on the drinking related measures involving a trend for subjects in the experimental condition to abstain more than those in the non-drinker control group. On other life functioning measures, however, subjects in the non-drinking experimental condition showed consistent improvement over their respective control subjects. Both of the controlled drinking groups reported more controlled drinking days than the non-drinking groups throughout the third year follow-up period.     

Stimulus generalization following extradimensional and intradimensional training in educable retarded children

Five related experiments investigating stimulus generalization following go/no-go discrimination training of educable retarded children are reported. Experiment 1 employed an Extradimensional paradigm in which generalization testing was on the hue dimension following training on an independent (orientation) dimension. Following True discrimination training only 25% of children showed a decremental stimulus generalization gradient on the hue dimension, though all children exhibited flat gradients in Pseudodiscrimination and S+ only control groups. An increase in difficulty of the orientation discrimination in Experiment 2 did not increase the number of decremental gradients. In Experiment 3, children who exhibited decremental gradients in Experiments 1 and 2 underwent further generalization testing with modified stimuli to establish a symmetrical gradient peaked at a hue S+ to be employed in Experiments 4 and 5. In these experiments an Intradimensional paradigm was employed with S+ and S? stimuli drawn from the hue dimension. Excitatory control by S+ and inhibitory control by S? were demonstrated, as were inhibitory consequences of S? such as peak and area shift.     

Stability criteria

Three approaches to the determination of behavioral stability were examined. In the first, a learning curve was fit to acquisition data (from Cumming and Schoenfeld, 1960), and the “experiment” stopped when the data approached sufficiently close to the theoretical asymptote. In the second, the data were analyzed for variability and linear and quadratic trend. In the third, the experiment was stopped when the magnitude of the daily changes in the data fell below a criterion. Accuracy was measured as deviation between the average value of the dependent variable when the experiment was stopped, and the average value over the last 100 sessions. The first approach was most accurate, but at the cost of requiring the most sessions and being the most difficult to apply. Both the second and third approaches provided acceptable criteria with a reasonable cost-accuracy tradeoff. The second approach permits a continuous adjustment of the criteria to accommodate the variability intrinsic in the experimental paradigm. The third, nomothetic, approach also takes into account the decreasing marginal utility of extended training sessions.     

The effect of additional variables on factor indeterminacy in models with a single common factor

Determinate solutions for the indeterminate common factor ofp variables satisfying the single common factor model are not unique. Therefore an infinite sequence of additional variables that conform jointly with the originalp variables to the original single common factor model does not determine a unique solution for the indeterminate factor of thep variables (although the solution is unique for the factor of the infinite sequence). Other infinite sequences may be found to determine different solutions for the factor of the originalp variables. The paper discusses a number of theorems about the effects of additional variables on factor indeterminacy in a model with a single common factor and draws conclusions from them for factor theory in general.     

The universal nature of human intelligence: Evidence from games

Mentally retarded individuals have relatively greater difficulty in dealing with strategic games and puzzles than with many other tasks. Consequently, it is of interest to find that strategic games have been played since ancient times, are played throughout the world, and that players who excel are frequently considered wise. Hidden within the more obvious differences between cultures, strategic games are an invariant expression of certain universal intellectual traits.     

Sex differences in realization of individual potential for achievement

Data from 4035 participants in Project TALENT were analyzed to examine the extent to which known sex differences in achievement held up when early potential for achievement was contolled. Original TALENT data, consisting of information on socioeconomic background, cognitive abilities, and educational and occupational aspirations, were collected in 1960 when members of the study sample were in Grade 9. Follow-up surveys measuring participants' educational and occupational attainment were conducted at 1, 5, and 11 years after the date of participants' expected graduation from high school. Women had higher high school grades and scored higher on a composite of academic ability tests taken in Grade 9 than did men. However, by 11 years after high school, men had acquired more education and were earning more money on the job. Sex differences in realization of achievement potential were found across all socioeconomic levels. At least part of the reason behind women's relative failure to translate potential into achievement may lie in the greater conflict, for women, between the roles of spouse/parent and the roles of student/worker: variables measuring the onset, duration, and extent of family-related commitments were more strongly related to female than to male realization of potential. Sex differences in achievement grew larger between the 5- and 11-year follow-ups as a greater proportion of women in the study sample became wives and mothers. The widening of the sex gap in achievement during this period was particularly pronounced among the subgroup of individuals who were in the top quartile of potential in Grade 9.     

Meditation,personality and arousal

A questionnaire survey of people who had learned a technique of meditation was carried out to assess persistence with practice, perceived effects of meditation practice and subjective experiences during meditation. The results suggested that a significant proportion give up meditating (42.9%) and that the subjective experience of meditation was similar to that of the hypnagogic state. Reported effects of meditation were generally physiological and psychological benefits related to relaxation.A personality questionnaire was also distributed and the results suggested that those attracted to meditation are significantly more neurotic and introverted than the general population but that those who continue with meditation are significantly less neurotic than those who give up their practice.These findings are discussed in terms of regression effects and in relation to a theory of personality and arousal.