Alternation behavior, spatial discrimination, and reversal disturbances following 6-hydroxydopamine lesions in the nucleus accumbens of the rat

The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes.     

The roles of stimulus repetition and hemispheric activation in visual half-field asymmetries

Hardyck, Tzeng, and Wang (1978, Brain and Language, 5, 56–71) hypothesized that ample repetition of a small number of stimuli is required in order to obtain VHF differences in tachistoscopic tasks. Four experiments, with varied levels of repetition, were conducted to test this hypothesis. Three experiments utilized the general task of object-picture naming and one utilized a word-naming task. Naming latencies constituted the dependent measure. The results demonstrate that for the object-naming paradigm repetition is required for RVF superiority to emerge. Repetition was found to be unnecessary for RVF superiority in the word-naming paradigm, with repetition actually reducing RVF superiority. Experiment I suggested the possibility that RVF superiority developed for the second half of the trials as a function of practice or hemispheric activation, regardless of repetition level. Subsequent experiments, better designed to assess this possibility, clearly refuted it. It was concluded that the effect of repetition depends on the processing requirements of the task. We propose that, for tasks which can be processed efficiently by one hemisphere, the effect of repetition will be to reduce VHF asymmetries; but tasks requiring substantial processing by both hemispheres will show shifts to RVF superiority as a function of repetition.     

Development of linear measurement in five- and six-year-old children

This study sought to identify the higher level knowledge (e.g., conservation of number) necessary for a child to understand linear measurement and to chart the growth of linear measurement in terms of the development of its components. To assess the presence of these components, a battery of 34 number, length, and distance tasks was developed and administered to 100 children between the ages of 63 and 78 months from kindergarten and Grade 1. Results indicate that there is a substantial delay between acquisition of the necessary components and emergence of a mature grasp of linear measurement. The collection of components for the number and length domains form scaled sets; within each domain, however, the pattern of development is marked by discontinuities. These discontinuities are interpreted as being associated with the need to reorganize number and length concepts. Most elements of the observed sequences of development are predicted by Piagetian theory, although others, such as asynchronies between conservation and transitive inferences of nonequivalence, are more consistent with Gagne's (1968) model of development.     

Imposture, inauthenticity, and feeling fraudulent

This paper deals with imposturous tendencies as ubiquitous and heterogeneous. They may enter into neurotic conflict and compromise, and also reflect an ego function disturbance involving multiple, shifting identities and subsequent problems in the subjective sense of reality of the self and objects. Imposture in a person undergoing analysis is, however, not only a function of individual character and psychopathology; it is also a function of certain inevitable requirements of the analytic situation which constitute a "pull" for its emergence. Vulnerable individuals will respond to this pull in revealing ways. Three case summaries illustrate the spectrum of imposturous tendencies.     

Profiles of adolescents' clothing practices: purchase, daily selection, and care

The purpose of this study was to examine the clothing practices in the daily selection, care, and purchase of clothing by adolescents in order to determine the extent these practices are performed independently or influenced by others, and to identify the factors involved in the activities. Clothing Practice Profiles were developed for both sexes in the three age groups corresponding to divisions in the Oregon 4-H program. The age group comparison revealed increasing frequency of independent activity in all three clothing practice areas (selection, care, and purchase) as age increased. Parental influence appeared to decrease with increasing age. Siblings' influence was minimal. Peer influence on selection and purchase practices increased. Media influence on daily clothing selection practices and clothing purchase practices in terms of wearing or buying identical or similar clothing was minimal. Media influence in advertisements increased with age, but purchases of advertised clothing items remained about the same. Age group comparisons were also made for selection factors and other care and purchase practices, including responsibilities for care of the member's and family's clothing, planning clothing purchases, sources of funds and methods of paying for clothing, use of clothing label information, and purchase factors.     

A factor analytic investigation of children's nighttime fear and coping responses

Checklists of children's nighttime fears and nighttime coping responses, completed by 178 8- to 13-year-old children and one of their parents, were factor analyzed. The resulting factors from each checklist were comparable for children and parents. The nighttime fear categories consisted of content around security either for one's personal life, loss, or safety or for others' safety and continued presence; imaginal-numinous concerns; and characteristics inherent in a nighttime situation. The coping categories consisted of responses related to internal self-control, social support, support from inanimate objects, prayer, and avoidance or escape either by controlling the inanimate environment or by controlling others.     

The performance of attention-deficit-disordered and normal children on conservation tasks

The present study was designed to investigate whether a specific subgroup of learning-disabled children (attention-deficit-disordered, ADD) differed from their normal counterparts on Piagetian tasks of conservation. The subjects were 34 third-and fourth-grade children. Seventeen children had been diagnosed as ADD; the remaining half were designated as normal. The two groups were equivalent in chronological age, mental age, and intelligence. The results indicated significant differences between the two groups on tasks tapping conservation of substance and number. These results may support the theory of a lag in the development of conservation in children with specific learning disabilities (ADD). Implications of the present research for therapeutic and remedial programs that serve ADD children are also discussed.     

The effect of diagonality on reconstruction of patterns by preschool children

The study examined the contribution of various aspects of pattern complexity to children's difficulty on reconstruction of patterns. Specifically, diagonal pattern components and spatial orientation of patterns were considered. Twenty-four children between 16 months and 31 months were presented eight 5-square patterns on a 3 X 3 matrix of squares. The squares lighted, went dark, and then could be relighted by the child if touched. Accuracy of reconstruction was determined by the number of squares correctly chosen by the child during reconstruction. The eight patterns were rated according to Leeuwenberg's code length method, Garner's rotation-and-reflection method, Halford and Macdonald's rating scale, and a simple count of the number of diagonal lines. Analysis of children's responding indicated that number of diagonal lines was more predictive of memory performance than the other three rating systems, implying that diagonality is an important feature of pattern complexity that should be included in ratings of patterns used in research with children.