Binocular fusion: A test of the suppression theory

Binocular fusion may be due to interocular inhibitory suppression, an hypothesis difficult to evaluate by phenomenal inspection. A test probe method (reaction time to a light pulse) was used to measure visual sensitivity during binocular rivalry and fusion. The absence of inhibitory effects during fusion fails to support the suppression theory of fusion.     

Oculomotor adaptation to wedge prisms with no part of the body seen

When S looks at a visual target through prisms, adaptive shifts in reaching behavior occur even though he sees no part of his body through the prisms. These shifts are caused by a change in the judgment of the direction of gaze (oculomotor change), which in turn is caused by two secondary prismatic effects: (a) asymmetry of the visual display and (b) apparent rotation about a vertical axis of a panel or wall facing S. The “asymmetry” factor contributes 22% of the total oculomotor change, and the “rotation” effect contributes the remaining 78%. Oculomotor change is not facilitated by eye-movzment activity. The adaptive oculomotor change induces a non-adaptive proprioception change about one-tenth as large as the oculomotor change. These findings are capable of accounting for the previously unexplained results reported by Wooster in 1923, and also for the current controversy about the role of reafferent stimulation in sensorymotor adaptation.     

The value of relative-time-spent ratings in task-oriented job analysis

Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist.     

Neuropsychiatric and experiential correlates of violent juvenile delinquency

This article reviews evidence regarding contributions of neuropsychiatric and psychological vulnerabilities to violent delinquency, and the interaction between intrinsic vulnerabilities and experiential factors in the genesis of antisocial juvenile behavior. Consideration is given to biochemical and physiological factors, genetics, medical status, and neurological, psychiatric, and neuropsychological factors. Implications for treatment are discussed.     

Some observations on a Popperian experiment concerning observation

In several places Popper describes a little experiment in which an audience is given the non-specific command Observe! He draws a number of conclusions from this experiment, in particular that observation takes place in the presence of theoretical problems, questions, hypotheses or points of view. The paper argues that while Popper's experiment is instructive, it hardly supports the strong conclusions he draws about the theory-dominance of observation in science. In particular, it is argued that talk of principles of selection which guide us to relevant observations, rather than the host of irrelevant observations of the naive inductivist, is misleading. Rather, it is the goals, aims, motives or interests of an observer that guide observation and these need not always involve a theoretical component.