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241.
To test the generality, across modality and across species, of a bidirectional effect of photic stimulation in infant rats found in previous experiments, two experiments examined the effects on heart rate (HR) of onset and offset of auditory stimulation in rats and of photic stimulation in guinea pigs. Experiment 1 demonstrated a unidirectional, decelerative response in rats 17 and 21 days of age to the onset and offset of a 1-kHz tone, at both low (80 dB) and high (100 dB) intensity levels and at 14 days to the onset of the high-intensity tone. Experiment 2 demonstrated that infant guinea pigs, which unlike infant rats are precocial and not nocturnal, responded to the offset but not to the onset of light, and that this response was decelerative. These results indicated a lack of generality of the bidirectional HR effect, and were discussed in terms of the orienting/defensive reflex distinction.  相似文献   
242.
Hardyck, Tzeng, and Wang (1978, Brain and Language, 5, 56–71) hypothesized that ample repetition of a small number of stimuli is required in order to obtain VHF differences in tachistoscopic tasks. Four experiments, with varied levels of repetition, were conducted to test this hypothesis. Three experiments utilized the general task of object-picture naming and one utilized a word-naming task. Naming latencies constituted the dependent measure. The results demonstrate that for the object-naming paradigm repetition is required for RVF superiority to emerge. Repetition was found to be unnecessary for RVF superiority in the word-naming paradigm, with repetition actually reducing RVF superiority. Experiment I suggested the possibility that RVF superiority developed for the second half of the trials as a function of practice or hemispheric activation, regardless of repetition level. Subsequent experiments, better designed to assess this possibility, clearly refuted it. It was concluded that the effect of repetition depends on the processing requirements of the task. We propose that, for tasks which can be processed efficiently by one hemisphere, the effect of repetition will be to reduce VHF asymmetries; but tasks requiring substantial processing by both hemispheres will show shifts to RVF superiority as a function of repetition.  相似文献   
243.
Bornstein’s hypothesis that there is a loss of color discrimination in tropical areas was not supported in earlier research in the Cook Islands. Using a more sensitive color vision test (the Farnsworth-Munsell 100-Hue Test), a loss of color discrimination in the red-purple and blue-green regions of the spectrum was found. The lack of sex differences in this color discrimination loss supports a physiological rather than a genetic explanation of the observed decrement.  相似文献   
244.
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   
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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   
248.
A W Koester  J K May 《Adolescence》1985,20(77):97-113
The purpose of this study was to examine the clothing practices in the daily selection, care, and purchase of clothing by adolescents in order to determine the extent these practices are performed independently or influenced by others, and to identify the factors involved in the activities. Clothing Practice Profiles were developed for both sexes in the three age groups corresponding to divisions in the Oregon 4-H program. The age group comparison revealed increasing frequency of independent activity in all three clothing practice areas (selection, care, and purchase) as age increased. Parental influence appeared to decrease with increasing age. Siblings' influence was minimal. Peer influence on selection and purchase practices increased. Media influence on daily clothing selection practices and clothing purchase practices in terms of wearing or buying identical or similar clothing was minimal. Media influence in advertisements increased with age, but purchases of advertised clothing items remained about the same. Age group comparisons were also made for selection factors and other care and purchase practices, including responsibilities for care of the member's and family's clothing, planning clothing purchases, sources of funds and methods of paying for clothing, use of clothing label information, and purchase factors.  相似文献   
249.
250.
The reliability of the Thematic Apperception Test   总被引:1,自引:0,他引:1  
Controversy over the TAT's reliability may stem largely from the mis-application of traditional psychometric measures, which are inappropriate to this test. The TAT is implicitly based on a multiple regression model, for which coefficient alpha is not appropriate. Also, test-retest correlations may be adversely affected by the standard instructions to write a "creative" story. In a test-retest study, 47 high school students retook the TAT after a year with instructions designed to break the implicit set to produce a new and different story from that previously written. The test-retest correlations were r = .48 (need for affiliation) and .56 (need for intimacy), or approximately the same as those for, e.g., the MMPI, 16PF, and CPI, It was demonstrated that this high stability over time was not due to subjects' recalling and repeating previous responses. Finally, it was shown that alpha considerably underestimated the test-retest reliability, contrary to assumptions of classical psychometrics.  相似文献   
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