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821.
Music cognition research has provided evidence that the tonal function of a musical event influences perception and memory. Our study investigated whether tonal function influences a basic temporal judgment, notably the detection of a temporal change disrupting a sequence's regularity. The sequences consisted of six musical events presented in isochrony (or with the fifth event occurring earlier or later): Three chords (instilling a tonal context) were followed by a tone (repeated three times). The tones fulfilled one of two tonal functions in the tonal context. Participants had to detect whether the sequence contained a temporal change and were not informed about tonal manipulations. Discrimination performance (as measured by d') showed an influence of tonal function on temporal change detection: Performance was better for the tonic tone (having the most important tonal function in the key) than for the unstable leading tone, the less stable mediant tone, and even than the stable dominant tone. The outcome shows the influence of listeners' tonal knowledge on a perceptual time judgment and suggests that processing of tonal and temporal structures interact at some stage of processing. 相似文献
822.
Surcinelli P Baldaro B Balsamo A Bolzani R Gennari M Rossi NC 《Perceptual and motor skills》2007,105(2):477-482
This study of the presence of alexithymic characteristics in obese adolescents and preadolescents tested the hypothesis of whether they showed impaired recognition and expression of emotion. The sample included 30 obese young participants and a control group of 30 participants of normal weight for their ages. Stimuli, 42 faces representing seven emotional expressions, were shown to participants who identified the emotion expressed in the face. The Level of Emotional Awareness Scale was adapted for children to evaluate their ability to describe their emotions. Young obese participants had significantly lower scores than control participants, but no differences were found in recognition of emotion. The lack of words to describe emotions might suggest a greater prevalence of alexithymic characteristics in the obese participants, but the hypothesis of a general deficit in the processing of emotional experiences was not supported. 相似文献
823.
Coelho RW De Campos W Da Silva SG Okazaki FH Keller B 《Perceptual and motor skills》2007,105(2):458-468
To assess use of imagery intervention in performance of two tennis motor skills the quasi-experimental design included a pre- and posttest and a control group. The tennis service shot and service receiving skill were selected as representative of open and closed skills, respectively. 48 subjects, male tennis players, whose ages ranged from 16 to 18 yr. (M = 17.2), were divided into two groups: (1) Technical practice only which was used as control group and (2) Imagery group who received both imagery and technical practice. Analysis of covariance showed a significant main effect for the imagery intervention on the closed skill (p = .002). Findings suggest that imaging a positive outcome may be more powerful in improving performance of closed skill movements than of open skill movements. 相似文献
824.
A validation study of a computerised test recently developed involving the Stroop effect, extended here by inclusion of a third, more difficult test series, is presented. Three groups of men belonging to the Swedish armed forces and adjudged to differ in their qualifications (20, 32, and 19 men of levels 1, 2, and 3, respectively) and a fourth group of 18 men convicted of serious crimes of violence were given this test, termed the Stress Strategy Test. Discriminant analysis of the test's 12 variables (four for each of the three test series) yielded a discriminant power of 65% for the total group, highest for the level 1 group (80%) and for the nonmilitary group (72%), results substantially better than obtained for the original version of the test with use of similar subject groups. 相似文献
825.
Dominguez FJ Lawrence C Halpern EF Drohan B Grinstein G Black DM Smith BL Gadd MA Specht M Kopans DB Moore RH Hughes SS Roche CA Hughes KS 《Journal of genetic counseling》2007,16(3):341-345
The self-reporting of cancer history is becoming increasingly important, as it frequently guides medical decision-making.
We studied the accuracy of personal cancer history using a self-administered questionnaire, comparing the results with the
Tumor Registry at our institution. Among 39,662 records, we identified 3614 women with a single cancer in the Tumor Registry
who reported none or one cancer on their questionnaire. The sensitivity in self-reporting cancers was 85.7%, ranging from
92.1% for breast cancer to 42.9% for leukemia. The accuracy for breast cancer and Hodgkin's Lymphoma was significantly better
than other cancers (p=0.00027, CI: 1.4–3.88). Analysis of patient's characteristics showed that Caucasians reported breast cancer more accurately
than Asian/Pacific Islanders (p=0.008), and those with Jewish ancestry more accurately than non-Jewish (p=0.0435). These results will help us to improve data collection and thus improve medical decision-making. 相似文献
826.
Part-list cuing—the detrimental effect of the presentation of a subset of studied items on recall of the remaining noncue items—was examined in three different study conditions and in the presence and absence of the noncues’ initial letters serving as item-specific probes. With a single study trial, part-list cuing was observed both with and without item-specific probes. By contrast, when participants received two study-test cycles or interrelated list items to a common story, part-list cues were found to be detrimental only in the absence of item-specific probes, but not in their presence. These results indicate that the role of item-specific probes in part-list cuing depends on encoding. The findings are consistent with a recent two-mechanism account of part-list cuing (Bäuml &; Aslan, 2006), according to which two different mechanisms mediate the effect in different encoding situations. 相似文献
827.
Natural variation in Drosophila larval reward learning and memory due to a cGMP-dependent protein kinase 总被引:1,自引:0,他引:1 下载免费PDF全文
Kaun KR Hendel T Gerber B Sokolowski MB 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(5):342-349
Animals must be able to find and evaluate food to ensure survival. The ability to associate a cue with the presence of food is advantageous because it allows an animal to quickly identify a situation associated with a good, bad, or even harmful food. Identifying genes underlying these natural learned responses is essential to understanding this ability. Here, we investigate whether natural variation in the foraging (for) gene in Drosophila melanogaster larvae is important in mediating associations between either an odor or a light stimulus and food reward. We found that for influences olfactory conditioning and that the mushroom bodies play a role in this for-mediated olfactory learning. Genotypes associated with high activity of the product of for, cGMP-dependent protein kinase (PKG), showed greater memory acquisition and retention compared with genotypes associated with low activity of PKG when trained with three conditioning trials. Interestingly, increasing the number of training trials resulted in decreased memory retention only in genotypes associated with high PKG activity. The difference in the dynamics of memory acquisition and retention between variants of for suggests that the ability to learn and retain an association may be linked to the foraging strategies of the two variants. 相似文献
828.
When participants are required to react to a stimulus, reaction times (RTs) are usually reduced when temporal uncertainty
about stimulus occurrence is minimized. Contrary to the common assumption attributing this RT benefit solely to the speeding
of motor processes, recent evidence suggests that temporal uncertainty might rather influence premotoric processing levels.
We employed a backward-masking procedure to further confine the locus of the temporal uncertainty effect. Participants performed
a discrimination task and indicated whether a spatial gap within a square was on the right or the left side. In addition to
the shorter RTs, visual discrimination accuracy was improved when temporal uncertainty was low. This result demonstrates that
temporal uncertainty influences stimulus processing at a perceptual level. 相似文献
829.
Nippak PM Mendelson J Muggenburg B Milgram NW 《Neurobiology of learning and memory》2007,87(4):610-623
We examined the benefits of a broad spectrum antioxidant diet and enrichment comprised of physical exercise, environmental stimulants and cognitive testing, on spatial memory performance in beagle dogs. Both aged (N=48) and young (N=16) beagle dogs (Canus familiaris) were tested yearly on a three-component delayed non-match to position spatial task for three consecutive years. The results showed that young enriched animals acquired the task in fewer sessions, made fewer errors, responded slower and made fewer positional responses, compared to aged enriched animals. An analysis restricted to aged animals revealed that antioxidant administration and enrichment resulted in fewer errors, slower responses and decreased positional responses, particularly in Year 3. Finally, cohort differences emerged, which exemplify the significance of early environmental intervention. Aged dogs that were housed with other animals and exposed to an outdoor environment in early development displayed greater benefits from both interventions. These findings indicate that long-term dietary intervention and enrichment can buffer age-associated cognitive decline. 相似文献
830.
Correll J Park B Judd CM Wittenbrink B Sadler MS Keesee T 《Journal of personality and social psychology》2007,92(6):1006-1023
Police officers were compared with community members in terms of the speed and accuracy with which they made simulated decisions to shoot (or not shoot) Black and White targets. Both samples exhibited robust racial bias in response speed. Officers outperformed community members on a number of measures, including overall speed and accuracy. Moreover, although community respondents set the decision criterion lower for Black targets than for White targets (indicating bias), police officers did not. The authors suggest that training may not affect the speed with which stereotype-incongruent targets are processed but that it does affect the ultimate decision (particularly the placement of the decision criterion). Findings from a study in which a college sample received training support this conclusion. 相似文献