摘要:

AbstractObjects never experienced before by 4 groups of monkeys were introduced into a free operant chain manipulation situation. The presence of the objects disrupted the manipulation response rates of 2 groups of animals differing in age and onset of a diet restricted in protein. Age controls receiving higher concentrations of protein in diets isocaloric with respect to the protein restricted diet, showed increased performance to these stimuli. The reinstatement of the chains alone condition resulted in a partial, but temporary recovery, of the manipulation response by low protein animals. This disruption in chain pulling behavior by malnourished monkeys may be similar to neophobic avoidance reactions previously observed in protein deprived monkeys.

ISSN:0012-1630    

DOI:10.1002/dev.420050402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractThe behavior of 88 children between 3 and 24 months was observed before a mirror, using an objective technique to examine the child's awareness of the image as his own. The results indicate the following age‐related sequence of behavior before the mirror: the first prolonged and repeated reaction of an infant to his mirror image is that of a sociable “playmate” from about 6 through 12 months of age. In the second year of life wariness and withdrawal appeared; self‐admiring and embarrassed behavior accompanied those avoidance behaviors starting at 14 months, and was shown by 75% of the subjects after 20 months of age. During the last part of the second year of life, from 20 to 24 months of age, 65% of the subjects demonstrated recognition of their mirror

ISSN:0012-1630    

DOI:10.1002/dev.420050403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractThe growth of brain and body were observed in mice selectively bred for high (H) or low (L) brain weight as adults. Line H brains tended to be heavier than unselected control (C) at birth and throughout the growth period; line L brains were similar in size to line C at birth, but the period of rapid growth was shortened. Thus different genetic mechanisms appear to be involved in phenotypic variation upward and downward and these seem to differ in the timing of action. Changes in water content indicate that both H‐ and L‐lines are maturing more rapidly than the C‐line. Differential temporal patterns of brain growth may have implications for behavioral development, particularly with respect to critical periods of sensitivity to external stimul

ISSN:0012-1630    

DOI:10.1002/dev.420050404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractRats were given daily isotonic saline or blank injections intraperitoneally during one of three postnatal periods (1–25 days, 25–50 days, 50–75 days) and were then subjected to 18 Hebb‐Williams maze problems beginning at 92 days of age. The rats receiving the blank injections from 25–50 days of age were impaired on later maze performance. Weight differences did not correspond to the effects of the control i

ISSN:0012-1630    

DOI:10.1002/dev.420050405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractRecent advances in the study of postnatal neural development, an adaptive process dependent on an intimate interplay of both genetic and environmental factors, are reviewed in mouse, rat, cat, and man. Since developmental neuroanatomical studies provide a useful and relevant way of approaching the much belabored and controversial nature‐nurture issue, behaviorally oriented workers should be made aware of the heuristic value of the field as both an impetus and a guide for future research, and as a means for providing explanations for observations unexplainable at the ethological or behavioral descriptive level. The conclusion reached in this review is that postnatal neural ontogeny is both environment‐dependent and environment‐expectant. To divide the process into mutually exclusive halves is indefen

ISSN:0012-1630    

DOI:10.1002/dev.420050406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractThree groups of 8 male albino rats within each of the age ranges 24, 50, and 100 days were trained on an active avoidance task to a criterion of 10 successive avoidances. The number of trials to criterion was found to be a monotonic function of age. One group at each age was tested immediately thereafter for passive avoidance of the conditioning chamber, another group was tested for passive avoidance after 25 days, and the third was tested for retention of active avoidance after 25 days. Groups at 50, 75, and 125 days were used as controls for the active avoidance retention groups. All animals took significantly fewer trials to relearn the active avoidance after 25 days than did controls on the acquisition of the original learning task. On passive avoidance 24‐day olds performed less efficiently than the older groups and failed to show any retention after 25 day

ISSN:0012-1630    

DOI:10.1002/dev.420050407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractSix adolescent male rhesus monkeys which had lived in pairs for 6–8 months were studied for behavioral adaption to 2 weeks of separation‐isolation and 4 days of reunion. The response to separation was 1–3 days of increased locomotion and object‐oriented behavior followed by a long term increase in self‐directed behaviors. The latter phase differed significantly from the anaclitic depression of infants separated from their mothers. Reunion produced one day of intense social activity followed by a return to behavior patterns characteristic of the preseparation period. A large component of the initial motor excitement following separation may be nonspecific response to gross change in the en

ISSN:0012-1630    

DOI:10.1002/dev.420050408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractVocalizations of young mice of 3 inbred strains, C57BL/6J, BALB/cJ, and C3H/HeJ, were recorded at 3, 6, 9, 12, 15, and 18 days of age. Recordings were made at ambient room temperature (23.5° ± 1.5°C) or under conditions of reduced temperature (2° ± 2°C). Strains differed in terms of rate of signaling, peak frequencies of signals, and average signal duration. Peak frequencies appear to be genetically coded, and did not vary with age or ambient temperature. The effects of reduced ambient temperature on C3H/HeJ and BALB/cJ pups were to extend the age span during which frequent signaling occurs, and to increase the average signal duration throughout that age span. The C57BL/6J pups emitted fewer signals under reduced temperature, but also showed an increase in signal duration.Strain differences in age functions of signaling and the differential impact of experience on the various parameters of the vocalizations suggest that these vocalizations may be a useful behavior in monitoring genetic‐experiental interactions and developmental rates in you

ISSN:0012-1630    

DOI:10.1002/dev.420050409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractRodent pups in distress emit 2 different types of ultrasonic calls. One is given in response to cold; the other in response to unusual tactile stimulation. The effects of these calls on adult behavior can also be classified into 2 categories. Some exert positive effects attracting the adult to the pup in distress and stimulating searching, retrieving, and nest‐building. Others cause withdrawal of the adult from the pup thereby causing cesation of rough handling or aggression. The ultrasounds elicited by cold could exert the positive effects whereas those elicited by tactile stimulation produce the withdrawal effect

ISSN:0012-1630    

DOI:10.1002/dev.420050410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY

摘要:

AbstractIn the course of a recent review of the effects of prenatal stress on offspring behavior, Archer and Blackman (1971) advanced some suggestions concerning the effects of the age of the offspring and their postnatal experience on the detection of prenatal stress effects. Specifically, they felt that studies they reviewed indicated that the behavioral effects of prenatal stress wane as offspring grow older and that “previous test experience (involving a mild or severe stress situation) causes the response to persist, enabling it to be detected in tests carried out when the animals are older

ISSN:0012-1630    

DOI:10.1002/dev.420050411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1972

数据来源: WILEY