Donald J. Dickerson

Keeping track of locations during movement in 8- to 10-month-old infants

Abstract Infants of 8 1 2 and 9 1 2 mo of age were tested for the ability to “keep track,” i.e., to determine the location of an object hidden in one of two covered containers before their left-right positions were reversed. Infants in both age groups for whom the covers were the same color and younger infants for whom the covers were different colors were generally unable to keep track. Only the older infants provided with different colored covers were able to do so. An analysis which separated keeping track from the sensorimotor stage 4 error indicated that (a) there was no contingency between the two and (b) there were developmental differences in the nature of the error.

Irrelevant stimulus dimensions and dimensional transfer in the discrimination learning of children

Abstract This experiment studied the learning of four extradimensional shifts by kindergarten children. These shifts differed with respect to the manner in which the irrelevant stimulus dimension of Problem 2 varied (within vs. between trials) and the status of this dimension in Problem 1 (relevant vs. constant). The main finding was that extradimensional shifts were learned faster when the irrelevant dimension of Problem 2 varied between trials and was constant within trials. This finding suggests that attention is not elicited so readily by dimensions which are constant within trials as by dimensions which vary within trials. The finding also allows for the consistent interpretation of many of the diserepant results of studies comparing reversal and extradimensional shifts. Performance was not affected by the status of the irrelevant Problem-2 dimension in Problem 1.

Cognitive Theory and Mental Development

Publisher Summary This chapter discusses the subject of cognitive theory and mental development. Cognitive psychologys subject matter is peoples mental states and processes. To expose these, it uses laboratory methods developed for the study of attention, memory, language, and perception, and especially the techniques of verbal learning experimentation. Its goal is to create generalized or nomothetic theory of human cognition. This chapter characterizes some of the changes in experimental psychology since 1950. Starting there allows, presenting a broad picture of the backdrop for the present state of affairs. The chapter describes the contemporary experimental psychology that is perhaps better called cognitive psychology, as having a poor match between its conception of scientific explanation and its methods for testing theory. The chapter explains two methods that hold some promise of meeting the implicit requirements of cognitive psychologys conception of scientific explanation. It is proposed that techniques of cognitive instruction and tests for individual differences can provide needed empirical validation for cognitive theory. The chapter also explains the methods that seem promising for general experimental psychology are being refined first by specialists in retardation and childhood.

Children's Inferences of Causal Events During Story Understanding

Second-grade childrens inference of causal events was studied. Each of the 24 children heard 2 stories containing 6 event episodes. Each story was followed by either a sentence recognition or a cued-recall test. Event episodes explicitly stated an event followed by its outcome. Enablement episodes explicitly stated an action that was causally antecedent to the event, followed by the outcome of the event. Filler (control) episodes explicitly stated an action causally unrelated to the event, followed by the outcome of the event. The results indicate that the children more frequently inferred events from enablements than they inferred enablements from events, and that the children did not make the inferences at the time of reading, but instead made them when queried at the time of the test. This conclusion is suggested because there was false recognition of events but no false recall.

Oddity preference by mental retardates

Abstract Three groups of severely retarded and three groups of mildly retarded individuals were given a series of five 10-trial oddity problems under non-reward conditions. The groups were presented with stimulus arrays containing one odd stimulus and two, three, or four identical stimuli. The results indicated that the mildly retarded group responded to the odd object slightly less than 50% of the time, significantly above chance expectancy, whereas the severely retarded group responded to the odd object approximately 33% of the time, significantly above chance expectancy for those groups with three and four identical stimuli. These findings suggest that oddity is a stimulus characteristic to which an approach response is made independent of its concurrent association with reward, and that the stimulus value of oddity differs for mildly and severely retarded S s.

Children's judgments of relative number by one-to-one correspondence: A planning perspective ☆

Abstract Factors influencing the use of a plan to judge the relative number of two sets by one-to-one correspondence were studied in three experiments with 4- and 5-year-old children. The plan used by a child was assessed by the pattern of responses shown over a series of different types of problems in which sets were arranged in parallel rows. One-to-one plans were used by children only when perceptual support was present that facilitated the pairing of elements. When the support consisted of lines that connected the elements in pairs, one-to-one plans were used spontaneously by nearly all children. When the support consisted of enclosing pairs of elements in the windows of a grid, one-to-one plans were not used initially but were adopted after the children had received experience in pairing the elements. The results were interpreted as indicating (a) that most children have one-to-one plans in long-term memory by 4 years of age and (b) that young children fail to use one-to-one plans in some situations either because they fail to retrieve them from memory or because they reject them as unworkable.