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411.
Sleep Loss and Temporal Memory   总被引:17,自引:0,他引:17  
Historical evidence suggests that sleep deprivation affects temporal memory, but this has not been studied systematically. We explored the effects of 36 hr of sleep deprivation on a neuropsychological test of temporal memory. To promote optimal performance, the test was short, novel, and interesting, and caffeine was used to reduce 'sleepiness'. A total of 40 young adults were randomized into four groups: control + caffeine (Cc), control + placebo (Cp), sleep deprived + caffeine (SDc), and sleep deprived + placebo (SDp). Controls slept normally. Caffeine (350 mg) or placebo were given just prior to testing. The task comprised colour photographs of unknown faces and had two components: recognition memory (distinction between previously presented and novel faces), and recency discrimination (temporal memory), when a previously shown face was presented. An interpolated task, self-ordered pointing, acted as a distraction. Caffeine had no effects within control conditions, but significantly reduced subjective sleepiness in SDc. Recognition was unaffected by sleep deprivation, whereas for recency, sleep deprivation groups scored significantly lower than controls. There was no significant improvement of recency with caffeine in the SDc group. Both sleep deprivation groups had poorer insight into their performance with recency. Self-ordered pointing remained unchanged. In conclusion, sleep deprivation impairs temporal memory (i.e. recency) despite other conditions promoting optimal performance.  相似文献   
412.
413.
Sound was presented to monkeys through one of two loudspeakers, each adjacent to a response key. A response on the key adjacent to the sound source was reinforced (correct response). A response on the other key produced a timeout (incorrect response). Under these conditions, over 90% of responses were correct within one or two sessions. When the procedure was changed so that a response on either key was reinforced independently of which speaker was sounding, similar control by location developed within one or two sessions. When conditions were modified by moving the keys away from the immediate vicinity of the speakers, the animals required about 20 sessions to reach a stable level of greater than 90% correct responses under differential reinforcement conditions. No control by location developed under nondifferential reinforcement conditions.  相似文献   
414.
This study investigated differences in demographic data, self-esteem, and coping skills for 225 students in Grade 7 who reported having a partner with whom they wanted to have a baby and 946 students who did not. Data were collected on the Rosenberg Self-esteem Scale, the Family Crisis-oriented Personal Evaluation Scale, and questions related to attitudes towards teen pregnancy and demographic data. The sample included 548 (46.8%) boys and 624 (53.2%) girls whose mean age was 13.2 yr. Students with a partner had significantly lower scores on the curriculum questions, self-esteem, and family coping skills, combined with higher scores in passivity. They indicated a desire to have a greater number of children, beginning by having their first child at a younger age and believed that having a baby improves a couple's relationship. Possible approaches may include effective teaching methods to overcome passivity through boosting self-confidence, goal-setting, and acquiring a purpose in life besides parenting a child.  相似文献   
415.
416.
In two studies, male and female preschoolers and third- and fourth-graders were tested on their abilities to match and generate affective labels for 19 types of emotionally laden situations. Age changes were found in the accuracy with which situations were both labeled and matched; the ability to match similar situations was more strongly related to age than was the ability to label emotions. Matching and labeling abilities were positively related to each other. Both age groups were best at labeling situations depicting happiness, anger, and sadness, and at matching situations depicting sadness, anger, and disgust, but both age groups were capable of matching a wide variety of emotions depicted in situations at a better than chance rate. Only situations depicting fear, nervousness, and embarrassment were not matched better than chance by either preschoolers or third- and fourth-graders.This research was supported by a grant to the first author from Boston University Graduate School, No. GRS-661-PS. Portions of this paper were presented in Toronto at the Biannual Meeting of the Society for Research in Child Development, April 1985. The authors would like to thank Gail Desmond, Lesley Landau, Ana Ortiz, Phyllis Sternlight, Mark Steward, and Orna Wolfson for their help in various phases of this project, and especially the Lowell Day Nursery for its cooperation.  相似文献   
417.
During 1982 and 1983 college commencement ceremonies, a tally was made of students who displayed personal adornment in addition to their traditional academic garb. Degree conferred, sex of recipient, and year of graduation were related to the frequency and forms (political and nonpolitical) of adornment. Bachelor of Arts candidates were more likely to be adorned than were Bachelor of Science candidates, women were more likely to be adorned than were men, and 1982 graduates were more likely to be adorned than were 1983 graduates. The wearing of antinuclear protest ribbons varied as a function of degree but not as a function of sex, and the wearing of nonpolitical forms of adornment varied as a function of sex but not as a function of degree. Results indicate that personalization of graduation attire follows patterns reported in studies of secular dress and adornment. This correspondence between everyday and ritual clothing expressions suggests that the graduation ceremony may be a useful microcosm for future field studies of adolescents' attitudes and social differentiation.  相似文献   
418.
The design of a versatile, low-cost, hermetically sealed, infrared photoplethysmograph is described. The device can be used for optical readings of changes in blood volume which occur with cardiovascular events. Advantages of the device are discussed.  相似文献   
419.
The design of a versatile and programmable transducer amplifier device with analogue display for self-monitoring of autonomic responses is described. The design features low cost, portability, and flexibility across direct-current transducer options (e.g., photoplethysmograph or thermistor). The device can be used for the visual or auditory display of continuous blood volume pulse or temperature measures where the relative amplitude or pulse rate is of concern. Auditory or visual biofeedback may be provided via the choice of a stacked bar-graph display or piezoelectric buzzer. A common circuit design to allow programming options for the estimation of heart rate, inter-beat interval, or pulse duration is provided.  相似文献   
420.
A study involving 597 adolescent girls in treatment for substance abuse between 1984 and 1986 at nine inpatient facilities in five states reveals a strikingly high prevalence of sexual abuse victimization. Over one-third (35.2%) of the girls acknowledged such a history. In an additional 9.7% of the cases, the primary counselor reported such a history for the patient, although she had denied it, at least at intake. Within this multiproblem, highly stressed population, the sexual abuse victim appears to show slightly different and often more serious psychopathology: a greater incidence of suicidal ideation and attempts, symptoms of agitation, and a sense of shame.  相似文献   
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