摘要:

AbstractTwo chimpanzees (Pan tryglodytes), Fanny and Jane, were presented with liquid and number conservation problems. One chimpanzee, Jane, was successful in solving both sets of problems in that she was not distracted by irrelevant transformations, being influenced only by changes in quantity. Her success appeared to be based on the ability to make inferences rather than on simple perceptual judgement of the final comparison. The results are compared and contrasted with those of Premack, in G. Woodruff, D. Premack, and K. Kennel [(1978). Conservation of liquid and solid quantity by the chimpanzee.Science, 202:99–994] and J. Mehler and T. G. Bever [(1967). Cognitive capacity of very young children.Science, 158:141–142; (1968). Quantification, conservation and nativism.Science, 162:979–981], and it is suggested that there may be a similarity of conservation development between chimpanzees an

ISSN:0012-1630    

DOI:10.1002/dev.420160102

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

年代:1983

数据来源: WILEY

摘要:

AbstractThe influence of LiCl preexposure on odor‐aversion conditioning produced by an odor‐LiCl pairing was studied in rats 7–31 days old. LiCl preexposure interfered with the acquisition of the odor aversion in both young and old pups. The time course of this effect depended, however, on the age of the pups. It lasted much longer (over 24 hr) if pups 8–17 days old were preexposed to LiCl than if the pups were preexposed when 30 days old (less 12 hr). Alternative interpretations of these data were discussed, and it was suggested that the age‐dependent differences in the time course of the LiCl preexposed effect may be determined in part by age‐related differences in the rat's excretory processes that clear lithium from the circula

ISSN:0012-1630    

DOI:10.1002/dev.420160103

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

年代:1983

数据来源: WILEY

摘要:

AbstractDystrophic (University of California, Davis, line 413) and normal control (Davis, 1. 412) chicks (Gallus domesticus) between 7 and 49 days old were tested for flight‐related pathology and righting ability. Drop‐evoked lateral flight developed in control chicks between 7 and 13 days. Dystrophic chicks never developed lateral flight. Both dystrophic and control chicks showed drop‐evoked wingflapping on the day of hatching. Also, dystrophic chicks had a normal but slightly higher drop‐evoked flapping rate than controls at 13 days. Thus, the neural circuits that initiated and generated the rate of drop‐evoked wing‐flapping, present in dystrophic chicks at birth, were intact at 13 days, when deficiencies in lateral flight and righting ability were already present. The righting behavior of control chicks was superior to that of dystrophic chicks at all ages from 7

ISSN:0012-1630    

DOI:10.1002/dev.420160104

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

年代:1983

数据来源: WILEY

摘要:

AbstractPatterns of interlimb coordination and lateral preference of spontaneous leg kicks were described for 8 normal human infants observed biweekly from 2 to 26 weeks of age. Newborn infants showed a high percentage of alternating movements, which were often supplanted by unilateral movements between 1 and 4 months. Simultaneous (in‐phase) kicks matured later than alternating kicks. No consistent lateral preferences were detected. The developmental course was marked by variability and discontinuities within each infant. We propose that asynchronous and asymmetrical maturation of subcortical tracts and/or muscle strength could account for these behavioral shift

ISSN:0012-1630    

DOI:10.1002/dev.420160105

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

年代:1983

数据来源: WILEY

摘要:

AbstractRats were either undernourished or fed normally during the suckling period, then at 1 and 5 months of age littermates were housed in enriched or impoverished environments for 30 days. The undernutrition caused lasting reductions in the weight and size of the cerebrum and in parameters of the hippocampus, but significant deficits were not observed in the thickness and area of the occipital cortex. Differential housing differed from early undernutrition in that its largest effects were on cortical parameters, but the effects of the two conditions did partly overlap. This meant that some nutritionally induced deficits could be modified later by manipulating environmental complexity. The cerebral response of the previously undernourished rats to differential environments was not distinguishable from that of well‐fed controls on the basis of the gross anatomical changes that were measured. Furthermore, no significant differences were found between the environmental effects in young and mature rats, although the latter's response tended to be somewhat less for most parameter

ISSN:0012-1630    

DOI:10.1002/dev.420160106

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

年代:1983

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420160107

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

年代:1983

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420160108

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

年代:1983

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420160109

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

年代:1983

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420160101

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

年代:1983

数据来源: WILEY