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241.
Research is reviewed suggesting that early school age children and older adults demonstrate a similar pattern of performance deficits (relative to the performance of young adults) on memory tasks, raising the possibility that age-related changes in some common factor might account for both memory development and memory decline. It is argued here that whereas “metamemory” theory of memory development does not provide a viable theory of memory decline, Craik's (F. I. M. Craik & M. Byrd, 1982, in F. I. M. Craik & S. E. Trehub (Eds.), Aging and cognitive processes, New York: Plenum; F. I. M. Craik & E. Simon, 1980, in L. W. Poon, J. L. Fozard, L. S. Cermak, D. Arenberg, & L. W. Thompson (Eds.), New directions in memory and aging, Hillsdale, NJ: Erlbaum) attentional deficit theory of memory decline provides a viable theory of memory development as well. Evidence supporting this position is reviewed, and directions for future research are discussed.  相似文献   
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Two experiments examined appetitive differential conditioning of the rabbit’s jaw movement response (JMR) in a two-phase procedure. The first phase entailed reinforced training with one conditioned stimulus (CS+), and the second phase involved intermixed presentations of CS+ and an unreinforced stimulus (CS?). In Experiment 1, CS+ was a 600-Hz tone, and CS-was either a 660-,1,000-, or 2,100-Hz tone. In Experiment 2, the magnitude of the water unconditioned stimulus (US) paired with CS+ was either 1, 3, or 9 ml. The experiments revealed that 1) the level of responding to CS-rose for several days and then declined over the remainder of training; 2) the physical similarity between CS+ and CS?directly affected the level of responding to CS?but had no discernable effect on the level of responding to CS+ ; and 3) US magnitude positively affected the level of responding to CS + and, to a lesser extent, CS?. The results are discussed in terms of their implications for Spence’s gradient interaction theory and Pavlov’s external inhibition hypothesis.  相似文献   
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When the luminance of a pattern that induces a sharp-edged illusory circle was decreased, both illusory contrast with the surround and the illusory depth difference between that circular area and the inducing elements reliably increased. Thus, changes in both of these effects apparently participate in (contribute to) the increased overall salience that had previously been found with decreased luminance. However, among individuals, the correlation between this improvement in contrast and this increase in depth was exceedingly small.  相似文献   
245.
Five- and 7-month-old infants were tested for sensitivity to the depth cue of shading. Infants were presented with two displays: a surface in which a convexity and a concavity were molded and a photograph in which shading specified a convexity and a concavity. Each display was presented under both monocular and binocular viewing conditions. Reaching was observed as the dependent measure. Infants in both age groups reached preferentially for the actual convexity in both the monocular and binocular viewing conditions. In the monocular photograph condition, the 7-month-olds reached preferentially for the apparent convexity specified by shading, indicating that they perceived it to be an actual convexity. These infants showed no significant reaching preference in the binocular photograph condition. This finding rules out interpretations of the infants’ reaching not based on perceived depth. The results therefore suggest that the 7-month-olds perceived depth from shading. The 5-month-olds showed no significant reaching preferences when viewing the photograph; thus, they showed no evidence of depth perception from shading. These findings are consistent with the results of a number of studies that have investigated infants’ sensitivity to pictorial depth cues. Together, these studies suggest that the ability to perceive depth from pictorial cues may first develop between 5 and 7 months of age.  相似文献   
246.
This experiment compared the effects of high-level and low-level postpassage questions, when presented immediately after the passage segment containing the answer to the question, on college students' free recall of expository prose passages. Low-vocabulary subjects' recall of high-level information not specifically quizzed by the postpassage questions was significantly greater in the condition in which the questions quizzed a high-level unit than in the low-question and no-question conditions, p less than .05. These results are interpreted as being consistent with a direct-access explanation which assumes that questions presented in close temporal contiguity to the quizzed information directly access that information in memory and that fewer associative links have to be traversed in the spread of activation from high-level units to other related information in the hierarchy. The effect of type of question in this experiment was compared with that found in an earlier experiment (Wilhite, 1982) involving delayed question presentation.  相似文献   
247.
This study concerns the manner in which the traumatic events suffered by the parent in the Nazi holocaust are communicated to the second generation born after the Second World War. Additionally we investigated the effects of differences in wartime experiences on subsequent communication behaviors. Communication behaviors in families whose parents had been prisoners in concentration camps were compared with those of families who had displayed active resistance (i.e., were partisans) during the Second World War. The data indicate greater legitimacy and openness in discussing holocaust-related issues in the homes of ex-partisans than in the homes of ex-prisoners in concentration camps. Also, sons and daughters of the former group have better knowledge of the holocaust and hold more favorable attitudes than do sons and daughters in the second group. The implications of these findings are discussed.  相似文献   
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Administered the Indian adaptation of the Rosenzweig P-F Study to 144 Scheduled Caste (SC) adolescent and 158 young adult male Indians. The results show that SC adolescents scored significantly higher on ego-defensive (ED) and extragressive (EA) and lower on need-persistive (NP), introgressive (IA) and imgressive (MA) reactions as compared to the Non-Scheduled caste (Non-SC) adolescents while there was no significant difference on any reaction among SC and Non-SC young adults. SC adolescents scored higher on NP and lower on obstacle-dominance (OD) reaction as compared to the SC young adults. Non-SC young adults were higher on EA, ED, and OD and lower on IA and NP as compared to those of adolescents. The pattern of reactions was ED-EA-NP-IA-MA-OD among adolescents and ED-EA-IA-NP-MA-OD among young adults of both the castes.  相似文献   
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