The effects of labeling dimensional values on setting differences in shift performance of kindergarten children

A reversal-shift paradigm was used to study the effects of dimensional labeling on the performance of 270 kindergarten children. Task 1 was a simultaneous discrimination problem in which form, size, and color were redundant relevant dimensions, In the shift task, one of the dimensions remained relevant with reward contingencies reversed, and the other two dimensions were made irrelevant. In both tasks, the children named the stimulus object to be chosen, prior to choosing, in terms of one of the three sets of dimensionnal values. Shift performance was predicted to be superior in groups required to name relevant dimensional values in comparison with groups required to name irrelevant dimensional values. Moreover shift performance was predicted to differ, within groups, for four different types of stimulus settings. Fmally, differences in performance on the settings were predicted to be larger for the irrelevant-labeling groups than for the relevant-labelmg groups. The results were found to be in good agreement with these predictions. The findings were discussed in relation to the subproblem analysis proposed by Tighe and Tighe (1972).     

Conditioning in human opiate addicts

Eight volunteers maintained on daily methadone participated in a classical conditioning procedure to determine which if any of the elements of narcotic withdrawal could be conditioned. The unconditioned stimulus was the injection of a small dose of naloxone. The unconditioned response was a brief precipitated withdrawal syndrome. The conditioning stimulus was a tone, odor, and injection of saline. Conditioning was successful in the pilot study in 5 of 8 subjects. The conditioned response consisted of tearing, yawning, lacrimation, systolic blood pressure increase, respiratory irregularities and subjective feelings of narcotic withdrawal sickness (nausea, muscle aches, chills). A second group of 8 subjects showed, in addition to the above, evidence of conditioning of heart rate, respiratory rate and skin temperature decrease. These laboratory findings support the clinical reports of a conditioned withdrawal syndrome and suggest ways to improve treatment results by detecting and extinguishing or modifying conditioned responses.     

Lump detection in simulated human breasts

Sixteen observers palpated silicone models of human breasts containing lumps 1.6-12.1 mm in diameter. Detectability depended on the size of the lump, producing a systematic psychometric function. In eight observers who participated in three or more sessions, performance improved with practice, with most improvement occurring within one or two 26-trial sessions. Three-week retention measures disclosed no appreciable decrease in performance, but a significant correlation was found between the number of lumps detected and duration of trial (p < .01). There was no difference in performance between four observers who used their preferred hands and four observers who used their nonpreferred hands. These data establish that examination of breast models for the detection of lumps simulating cancer is a task amenable to experimental analysis.