Effects of Eltoprazine Hydrochloride on Predatory Behavior in Rats

Treatment of rats with the potent antiaggressive compound eltoprazine hydrochloride (1.0 & 2.0 mg/kg) slowed both predatory attack and killing of frogs. These results demonstrate a specific predation-inhibiting action of the drug which is not obscured by the elements of conspecific aggression seen during muricide. Unlike the closely related compound fluprazine, eltoprazine increased both attack and kill latencies implying that the effects of the two drugs on predation are mediated by at least somewhat distinct drug actions. It is further suggested that eltoprazine may be more specifically antiaggressive in its actions than related phenylpiperazine compounds.

     

Rhythmic motor behavior of preambulatory motor impaired,down syndrome and nondisabled children: A comparative analysis

The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990.     

Sex-role aspects in the development of children's vocational knowledge

Recent research suggests important age and sex differences in the sex-typing of children's vocational interests. The present study adds to this area by examining several dimensions of job choices in children of four age groups (early and late preschool, second and fourth grade). The 120 children interviewed were asked three fixed-choice questions regarding nine jobs, along with open-ended job choice items. Analysis of age effects on several predetermined dimensions showed that older children were more selective in personal job choice, especially in regard to jobs attributed to the opposite sex. Avoidance of choices associated with the other sex was stronger in boys, but other sex differences were dependent on mode of inquiry rather than on sex. Girls were less limited than boys in job interests when asked about specific jobs but expressed more restricted choices on open-ended items. Implications of these findings both for further research and educational practices are considered.     

Figural emphasis and person perception

Based on Jones and Nisbett's (1972) proposition that actor-observer differences in causal attributions derive from differences in attentional focus, it was hypothesized that observers' focus of attention would influence their causal attributions for an actor's behavior. More specifically, it was predicted that the behavior of an actor who was the focus of attention by virtue of some salient physical attribute would be attributed by observers more to dispositional causes and less to situational causes than would the behavior of a less physically salient actor. The manipulations of physical salience were based upon Gestalt laws of figural emphasis in object perception. They included brightness (Study I), motion (Study II), pattern complexity (Study III), and contextual novelty (Studies IV and V). The results revealed that the salinece of the actors' environments (i.e., the other people present) rather than the salience of the actor him/herself had the most consistent influence on causal attributions. When environmental salience was high, behavior was attributed relatively more situationally than when it was low. Prior research findings are considered in light of the proposition that causal attributions for an actor's behavior vary only with the salience of his/her environment, and additional implications of this phenomenon are suggested. Some ambiguities in the application of Gestalt principles to the perception of people are discussed.     

Effects of food deprivation and reinforcement magnitude on conditioned suppression

In Experiment I, the responding of rats lever pressing on a variable-interval schedule for sucrose solution was partially suppressed by a variable duration conditioned stimulus followed by shock. When food deprivation was increased, response rates during and before the conditioned stimulus increased monotonically. Varying the concentration of sucrose across blocks of sessions or from session to session in a semi-random sequence had little effect on response rates either before or during the conditioned stimulus. With a fixed sequence of increasing concentrations across a five-session block, increased concentration produced much more rapid increases in response rates before than during the conditioned stimulus. In Experiment II, rats were presented with the same sequence of increasing concentrations across a five-session block. When tested at 80% body weight, response rates increased rapidly as concentration increased, but at 100%, body-weight rates increased only slightly. The effect of a change in body weight in Experiment II thus mimicked the effect of the conditioned stimulus in the latter part of Experiment I. These findings support the view that the effect of a pre-aversive conditioned stimulus is similar to that of a change in food deprivation, but unlike that of a change in reinforcement magnitude.     

Book reviews

Hamilton, Vernon and Veronon, Magdalen D. (Eds). The Development of Cognitive Processes. London and New York: Academic Press. 1976. Pp. 772. £21.00. ISBN 0 12 321750 4.

Miller, G. A, and Johnson-Laird, P. N. Language and Perception. Cambridge University Press. 1976. Pp. viii + 760. £12.50. ISBN 0 521 21242.

Neisser, U. Cognition and Reality. San Francisco: Freeman. 1976. pp. 230. Hardback $11.00; paperback $4.95. ISBN 0 7167 04781.

Norman, D. A. Memory and Attention. Second edition. New York: Wiley. 1976. Pp. 262. £8.45.

Hammond, K. R. and Joyce, C. R. B. (eds). Psychoactive Drugs and Social Judgment: Theory and Research. New York and London: Wiley. 1975. Pp. 278. £9.25. ISBN

Fodor, J. D. Semantics : Theories of Meaning in Generative Grammer. Sussex: Harvester Press. 1977. Pp. 225. £12.95. ISBN 0 85527 500 6.

Plomp, R. Aspects of Tone Sensation. London: Academic Press. 1976. Pp. id + 167. £6.50. ISBN 0 12 558350 8.

Fite, K. V. The Amphibian Visual System. London: Academic Press. 1977. Pp. 374. £20.95. ISBN 0 12 257450 8.

Eliot, J. and Salkind, N. J. Children's Spatial Development. Springfield, Illinois: Charles C. Thomas. 1975. $23.50. Pp. 296. ISBN 0398 03210 6.

Wong, R. Motiviation : A Biobehavioral Analysis of consummatory Activities. London: Collier-Macmillan. 1976. Pp. 326. £ 4.95. ISBN 0 0242 9400 4.     

On the limits of Kagan’s impulsive reflective distinction

A logical analysis is made of the Matching Familiar Figures (MFF) Test on the basis of which children have been classified as "impulsive" or "reflective." The reflective strategy is implicitly preferred to the impulsive because the reflective child makes fewer errors though generally taking longer to make his first response. We show that the test allows the choice of a number of "game plans" and speed-accuracy tradeoffs which in practice may not be very different. Error rates may not indicate perceptual sensitivity, in any case, since sensitivity and response factors may be confounded in the error rate. Using a visual running-memory-span task to avoid the inherent difficulties of the MFF test, we found that children previously classified on the basis of that test as impulsive or reflective did not differ in recognition accuracy but did differ in response bias and response latency. Accuracy and bias are estimated by way of Luce's choice theory (Luce, 1963), and the results are discussed in those terms.     

Overselectivity,developmental level,and overtraining in autistic and normal children

Thirteen autistic children were compared to 13 normal children, matched to them in mental age, on performance of a visual discrimination task. Form, color, and size were relevant and redundant cues. The groups did not differ significantly in mean trials to reach criterion or in breadth of learning, and both groups increased their breadth of learning after 50 trials of overtraining. Form was preferred to color and size by both autistic and normal children. Within each group, rank on mental age was highly correlated with rank in breadth of learning. Verbal and nonverbal autistic children did not differ in breadth of learning or in dimensional preference. Even nonverbal autistics equaled the performance of their normal controls. Our results suggest that overselective attention is better understood as part of a general developmental lag in cognition in autistic children than as a specific deficit underlying psychotic behavior.This research was supported in part by NIMH Grant 11440, O. I. Lovaas, principal investigator. The authors thank Dr. Lovaas and Dennis C. Russo for their helpful criticisms of an earlier draft.