Central and peripheral cholinergic involvement in the habituation of investigatory head poking in rats

The effects of some centrally and peripherally acting cholinergic agonists and antagonists on locomotor exploration and investigatory head poking were studied in rats. An apparent disruption of within-trials habituation of locomotion and head-poke frequency was demonstrated for arecoline, nicotine, carbachol, scopolamine, and methylscopolamine. It is suggested that the effect may be a consequence of a drug-induced depression of initial activity. When this factor was eliminated, both scopolamine and methylscopolamine showed some slight attenuation of habituation. The increase in head-poke duration over time in controls was blocked by scopolamine; although peripheral factors were involved, the scopolamine effect had a singinficant central component. The results are discussed in relation to hypothetical links between the cholinergic system and habituation.     

Effects of selective forebrain noradrenaline loss on behavioral inhibition in the rat.

Virtually total depletion of cortical and hippocampal noradrenaline by stereotaxic injection of 6-hydroxydopamine into the fibers of the dorsal noradrenergic bundle produced no impairment in acquisition learning of a runway response for food reward. Extinction of this response, once learned, was markedly slower in the treated group than in controls, the treated animals perseverating in rapid running to the goal box even with no food present there. Similarly, no impairment was found on acquisition of a continuously reinforced lever-pressing response for food. Extinction of this response, however, was again slower in the treated group. Subsequent acquisition of a successive light-dark discrimination task was also slower in the treated group, with these animals perseverating in responding to the negative stimulus. Although selective forebrain noradrenaline loss does not impair the acquisition of appetitive responses, the suppression of responses in the absence of reward is impeded. A parallel is drawn with those effects found classically after surgical lesion to the hippocampus.     

Short-term memory in deaf and hearing children in relation to stimulus characteristics

Experiment 1 examined short-term memory with a serial probe task in 20 younger (mean age: 6 years, 3 months) and 20 older (mean age: 8 years, 8 months) deaf children. Four sets of stimuli were used: familiar animals, unfamiliar nonsense forms, fingerspelled letters, and lower-case print. In contrast to earlier research with hearing children, strong primacy effects were found with all stimuli at both ages, with frequent gestural and/or oral labeling but little cumulative rehearsal evident. To determine whether results were uniquely tied to deafness, identical procedures were used in Experiment 2 with 20 younger (4 years, 9 months) and 20 older (5 years, 10 months) hearing children. Again, overt activity was common, with strong primacy effects on animals and nonsense forms in the older group and on animals in the younger group. Contrasts between present and earlier findings suggest the need to consider the degree to which stimulus labels are overlearned, the role of nonverbal mediators in rehearsal, and the effects of changing educational experiences.     

Conservation training in four-year-old children

In Experiment 1 two training procedures were used to teach four-year-olds to conserve. Verbal rule instruction consisted of providing verbal rules and demonstrations of the operations referred to by the rules. Feedback consisted of providing verbal feedback contingent upon the children's responses. One week after training on conservation of number and length the children were given a posttest which included tests of conservation of number, length, and mass. Children who were given verbal rule instruction conserved significantly more on the number and length posttest problems than children who were not. However, this learning did not transfer to the mass problems, possibly because mass is not naturally acquired until some time after conservation of number and length. The feedback training procedure had no effect on conservation performance. In Experiment 2, the verbal rule instruction procedure was used to train four-year-olds on conservation of length and mass. One week after training the children were tested on both conservation of number, which is typically acquired before length and mass, and conservation of weight, which is typically acquired after length and mass, as well as on conservation of length and mass. Children who were given training conserved more on all four types of problems than children in the control group.     

Behavioral inference in young children

Three experiments are reported on behavioral inference in children of 3 to 5 years of age. In each experiment the children learned two separate sequences of behavior which they were required to put together in the final test stage in order to obtain a reward. In the first experiment moderate levels of behavioral inference were obtained, although a relatively high proportion of children failed to respond in the test phase. In the second experiment different instructions were used in the test phase, the number of nonresponders was greatly reduced and a much higher proportion of children showed behavioral inference. The third experiment obtained similar results under conditions which excluded the possibility of mediation during a memory test, which was included in the previous experiments. It was concluded that behavioral inference is found, under suitable conditions, in children as young as 3-years-old, and that reports by other investigators of failure to find such inference up to the age of about 8 were due to problems with apparatus and instructions.     

The effects of attention-directing training on recognition memory task performance of three-year-old children

Thirty-eight 3-year-old children served as subjects in an investigation of recognition memory in which schematic faces differing only in the orientation of the eyes were employed as stimuli. A pretest was administered to all children, after which the two experimental groups received training in either attention to the distinctive feature of the training stimuli (also schematic faces) by means of a matching task, or in labeling the faces according to how they looked (sleepy, happy, sad, mad) and in using the labels to perform a matching task. After the training session all children were given a posttest on recognition memory of the faces. The verbally trained group obtained significantly higher scores on the posttest than either the feature or control groups. These results indicate that although the children were able to discriminate the faces, evidenced in their ease of performance on the training tasks, they were not able to use this knowledge unless given training in attaching labels to the stimuli, which enabled them to store the information for later use. Results are discussed in light of Gibson's (1969) theory of the developmental interrelations of cognitive processes.     

Teacher Beliefs,Classroom Interaction and Personal Causation1

The study reports relationships between teachers' belief systems (Harvey), a teacher-pupil interaction measure of classroom influence, pupils' perception of the dimate of the dassroom, and pupils' academic achievement. Results demonstrate that more complex teachers encourage more pupil influence, and are perceived as having a more origin climate. In classrooms of high pupil influence and perceived origin climate, the pupils have higher academic achievement. These results are discussed in terms of the theory of personal causation and are cited as evidence for the value of the study of action sequences as related to verbal-utterances of the actors.     

Touch: a computerized bibliography.

A computerized bibliography of references relating to "touch" has been prepared. It currently contains approximately 4000 references which belong under the following general categories--physiology and neurophysiology; sensation; perception; cognition; social, cultural, and developmental issues; clinical pathology; the deaf and blind; tactile communication and tactile aesthetics. References have been obtained primarily from the Psychological Abstracts, with classification codes added on the basis of the abstract's content. Master copies and keyword searches may be obtained on the most up-to-date version of the bibliography.     

Between-theory and within-theory conflict in explaining context effects in impression formation

Research on context effects in impression formation has taken the form of testing competing predictions from the averaging model and the meaning shift model. This between-theory conflict has been unprofitable because neither theory has yet acquired the degree of specificity necessary to generate unequivocal predictions in this area. The research has been useful, however, in identifying each theory's capacity to generate self-contradictory predictions. Future research on this topic can most profitably be addressed to resolving these within-theory conflicts.     

Nonverbal assessment of interpersonal affect.

Two nonverbal methods for assessing degree of interpersonal attraction were explored. Twenty children ranging from 11 to 13 years of age were asked to select two liked and two disliked classmates of the same sex. On four different trials, subjects selected one geometric block to represent themselves and one to represent a pre-selected classmate, then placed the figures on a ruled board. Distance between objects was measured and found to be significantly related to degree of peer liking. In addition, subjects were asked to draw each of the four peers. The human figure drawings were rated for total pictorial detail which was found to vary strongly across magnitude of liking for female subjects, and for parts integration which was found to vary with degree of peer liking for both sexes. The degree of rated positive affective tone of drawings was also found to increase with liking. Implications for the use of these two interpersonal assessment techniques in clinical practice were discussed.