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K G White

Publications and source records attributed to K G White.

4 recordsLinked to original sources
PubMed1992

Successive independence and behavioral contrast in a closed economy.

Two pigeons had access to multiple concurrent schedules of reinforcement for 24 hours per day in their home cages. The variable-interval schedules comprising the multiple concurrent schedules were varied across 16 conditions. In three sets of conditions, one schedule was varied while its concurrent alternative and the concurrent schedules in the other component were held constant. Behavioral contrast was observed; that is, as the rate of reinforcement arranged by the varied schedule decreased, response rates on the constant schedules typically increased. These conditions formed part of two larger sets of conditions in which the concurrent schedules in one multiple-schedule component remained constant while the concurrent schedules in the other component were varied. Successive independence was found, in that behavior allocation during the constant component did not vary as a function of the reinforcer ratios in the varied component. Successive independence between components in multiple concurrent schedules is a robust result that occurs in closed economies and under conditions that promote behavioral contrast.

Animals↗
PubMed1988

Low dose scopolamine affects discriminability but not rate of forgetting in delayed conditional discrimination.

The effect of scopolamine on remembering was examined in a delayed conditional discrimination procedure with rats. Remembering was quantified by a negative exponential function fitted to estimates of discriminability derived from a signal detection type of analysis. This function had two parameters: a measure of initial discriminability of the sample stimuli in the absence of a memory requirement (at zero delay) and a measure of rate of forgetting. Eight rats were trained on an auditory delayed conditional discrimination task until they were showing stable performance. Each rat then received doses of 0, 0.005, 0.014, 0.042, 0.125 and 0.375 mg/kg scopolamine IP in a saline vehicle. There was a highly significant, largely linear, decrease in initial discriminability. This was obvious even at the lowest dose of scopolamine. Poorer memory, as demonstrated by an increase in b, was only apparent at the highest dose. Significant changes in per cent of correct responses were also only obtained at higher doses. These results show that initial discriminability and rate of forgetting are pharmacologically as well as theoretically independent. They suggest that the measure of initial discriminability used here is a particularly sensitive measure of at least some types of cholinergic dysfunction; and they also suggest that effects of scopolamine in other working memory tasks could be more a result of changed stimulus processing than of impairment of memorial processes.

Animals↗
PubMed1979

Primary eye care for the pediatric patient.

The primary care needs of the pediatric patient include the measurement of norms and deviations in the newborn (neonate) and subsequently, developmental milestones. Considerations of such norms and deviations must include familial and hereditary implications, systemic conditions and general health status. Deviations from the expected norms in the newborn and during development must be evaluated by the parent (as the true primary pediatric provider) and responsible health and eye care professionals. Such evaluation should include a sensitivity and awareness of the ocular and visual status, identification of norms and deviations and appropriate courses of action.

Child↗