摘要:

AbstractSeveral studies have confirmed that diet selection patterns of adult rats are at least partially estabilished as a result of early experiences with food‐related stimuli present in the milk of a lactating female (e.g., Capretta&Rawls, 1974; Galef&Clark, 1972; Galef&Henderson 1972). The present experiments were designed to investigate whether preweanling rats would similarly modify their acceptance of an ethanol solution following exposure to this cue in a nursing context. In Experiment 1, 8‐, 12‐, and 16‐day‐old rats were given ethanol, delivered intraorally in compound with milk, while given the opportunity to suckle an anesthetized dam. Subsequent testing revealed that 12‐ and 16‐day‐old subjects evidenced enhanced intake of the ethanol relative to controls, while 8‐day‐olds did not. Finally, the oldest (16 days of age) subjects also expressed a conditioned aversion to the milk when tested 24 hr after conditioning and ethanol‐ingestion testing. Experiment 2 demonstrated that the critical factor for ethanol conditioning was the opportunity to suckle, rather than the simultaneous presence of milk. Finally, the aversion to milk observed in Experiment 1 was shown to have resulted from long‐delay learning, due to the ingestion of a sufficient dose of ethanol during testing to serve as an aversive unconditioned stimulus (Exp. 3) © 1

ISSN:0012-1630    

DOI:10.1002/dev.420260302

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

年代:1993

数据来源: WILEY

摘要:

AbstractThe relative impact of early versus delayed visual experience on intersensory development was studied by manipulating the timing of visual experience of bobwhite quail (Colinus virginianus) embryos and hatchlings. Previous studies with quail chicks have revealed that: (1) Socially reared chicks require only maternal auditory cues to direct their social preferences in the first 2 days following hatching; (2) by 3 days following hatching chicks require both auditory and visual maternal cues to direct their social preferences; (3) chicks which have received unusually early visual experience as embryos require both auditory and visual cues by 24 hr following hatching, indicating an accelerated pattern of the emergence of intersensory functioning; and (4) chicks reared under conditions of attenuated social and visual experience continue to rely on matenal auditory cues alone at 4 days following hatching, indicating a decelerated pattern of early intersensory functioning. In the present study, quail chicks that received both early visual experience as embryosanddelayed visual experience as hatchlings exhibited a pattern of both auditory and visual responsiveness like that seen in normally reared chicks. These results indicate that, at least under the present experimental conditions, the influence of early and delayed visual experience on perinatal perceptual development appears to be relatively comparable in effect © 1993 John Wiley&Sons, Inc

ISSN:0012-1630    

DOI:10.1002/dev.420260303

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

年代:1993

数据来源: WILEY

摘要:

AbstractElemental associations permit subjects to solve problems when the significance of the relevant stimulus elements are consistent from trial to trial but do not allow subjects to solve problems that require them to construct and use representations of stimulus conjunctions or configurations to guide their behavior. Recent research with brain‐damaged and developing animals has led several theorists to propose that elemental and configural associations depend on different neural systems. Some evidence suggests that changes in children's learning that occur when they are about 4.5 year old may be partially due to developmental differences in access to the elemental and configural association systems. Two experiments are reported that support this hypothesis. Children at least 4.5 years old were able to solve the transverse patterning problem and a conditional discrimination, two problems that require configural association solutions. Younger children did not solve these problems but were able to solve problems constructed from the same stimulus materials that permitted an elemental association solution. These results suggest that children may not gain access to the configural association system until they are about 4.5 years old and support the hypothesis that the configural association system depends on different, later developing neural structures than does the elemental association system © 1993 John Wiley&Sons, I

ISSN:0012-1630    

DOI:10.1002/dev.420260304

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

年代:1993

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420260301

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

年代:1993

数据来源: WILEY