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951.
In a Sternberg experiment, the influence of rhythmic acoustic stimuli on the scanning rate of short-term memory was studied. During the experiment, 60 subjects heard rhythmic or arrhythmic impulse noises with different rates of repetition. Results showed that the scanning rate of short-term memory is lowest if the impulses are arrhythmic. With rhythmic impulses at high rate of repetition, an accelerated scanning rate was obtained. The results can be interpreted as consequences of interference processes and as adaptational effects of internal processing rhythms.  相似文献   
952.
24 men and 24 women were randomly assigned in equal numbers to an Alcohol group, a Placebo group, or a Control group. The alcohol dose was 1.0 ml of 100% alcohol/kg of body weight. Subjects were tested three consecutive times using Stroop's Color Word Test. The dependent measures were total time needed to complete the test, number of errors made and number of hesitations. Data were grouped into three blocks of 100 words. Results indicated that number of hesitations was too insensitive a measure to yield any significant effects. On the two first measures alcohol had a detrimental effect in that the Alcohol group needed more time to complete the test and made more errors than the Placebo group. There was also a significant interaction of alcohol dose by sex by blocks on both these measures, indicating that the detrimental effect of alcohol over time was restricted to women. Different implications of the results were discussed.  相似文献   
953.
After the evaluation of the anamnestic, clinical, and paraclinical data of 100 children and young persons with functional headache, the conclusion is reached: It is not considered cogently necessary; on clinical, paraclinical, therapeutic, and prognostic grounds, to differentiate between tense headache and migraine (complicated migraine forms excepted) in functional headache in children. A prevalence of girls below the age of 12, as described in literature, was not confirmed. Only from the age of 12 is there an increase in proportion of girls as first sufferers of functional headache. Short-term prognosis suggests effective non-medicamentive treatment.  相似文献   
954.
Increased plasma cortisol levels are found not only in patients with Cushing disease but also in patients suffering from endogenous depression. Because patients with endogenous depression fail to show any clinical signs of Cushing disease, it is supposed that the cells of these patients are relatively resistant to increased glucocorticoid levels. To test this hypothesis 20 patients with endogenous depression and 20 healthy controls were examined for plasma cortisol level and modulation of mitogen induced lymphocyte transformation by glucocorticoids. Results point to a relative resistance of patient's T-lymphocyte transformation to the inhibitory effect of glucocorticoids when compared with controls.  相似文献   
955.
Shape from shading in different frames of reference   总被引:1,自引:0,他引:1  
It has often been reported that, in the absence of information about the direction of illumination, people interpret surface convexities and concavities in accordance with the assumption that illumination comes from above. However, 'above' could mean with reference to gravity, the head or the retina. Yonas et al reported that four-year-old infants use the head more than gravity as the frame of reference in interpreting surface relief but that seven-year-olds make about equal use of the two frames of reference. The potency of these two frames of reference when acting separately and when pitted against each other was measured on adult subjects. For all subjects the 'assumption' about the direction of illumination was predominantly with respect to the head. The gravitational frame was used only when the headcentric frame was irrelevant, and then not consistently.  相似文献   
956.
MRI technique was used to examine the size and symmetry of the plana temporale in 19 dyslexic students in grade 8 and in carefully matched control subjects. The results demonstrated a high frequency of planum symmetry among the dyslexics (70%) whereas symmetry was observed in only 30% of the control subjects. It was not possible to demonstrate any clear association between symmetry/asymmetry of planum temporale and handedness. Word-reading strategies among the dyslexics and control subjects were investigated with computerized tasks where accuracy and naming latency were recorded. All subjects with pure phonological deficits in reading had symmetrical plana temporale indicating a possible neuroanatomical basis for a characteristic symptom of linguistic processing deficiency in developmental dyslexia.  相似文献   
957.
Fourteen patients with Parkinson's disease (rigidity and unilateral tremor as main symptoms) were treated with stereotactic thalamotomy. The operation was performed in either the left or right ventrolateral thalamus, depending on which hand (or foot) was most affected with tremor. Nine patients were operated on the left side and four on the right side. All patients were tested for asymmetry of language functioning with dichotic presentations of consonant-vowel (CV) syllables. The patients had to indicate which of the two syllables he/she heard on each trial. Dichotic listening was performed before and after the operation, as well as during electrical stimulation of the VL nucleus just before the lesion was carried out. The results revealed essentially three things: an overall reduced right ear advantage (REA) in the patient group compared to what is known from studies of healthy individuals; an increase in REA during left-sided stimulations; and a marked reduction in REA after left-sided lesions. It is concluded that the present data support the notion put forward by Ojemann (e.g., 1975) of a lateralized activating gating mechanism in the left VL nucleus that gates access for language information to the appropriate cortical areas. The gating mechanism seems to be activated by stimulation, and deactivated after lesions. Dichotic listening may thus be a heuristic instrument in assessment of language functions in Parkinson patients.  相似文献   
958.
The aim of the present experiment was to investigate the effects of head and eye turns on the ear advantage in dichotic listening (DL) to CV-syllables. Since head and eye turns also mean focusing attention to either the left or right side in space, a second aim was to evaluate recent arguments that ear advantages seen in DL are caused by the perceived position in space of the sound source. Forty right-handed females had 36 trials of CV-syllables under four different instructions. One group (n = 20) was instructed to turn their head (but not their eyes) to the right, the left, or straight ahead during stimulus presentations. The fourth condition was a standard (no instruction) condition. A second group (n = 20) had the same instructions but were told to turn their eyes instead of their heads. Conditions were pseudo-counterbalanced across subjects. Consistent with other studies, results showed a right ear advantage (REA) in both groups during all conditions. However, the REA was largest for the standard condition. Also, more subjects showed a REA during the standard condition, and especially compared to the turn-right condition. It is concluded that dichotic performance is not caused by selective attention to either side in space, and that lateral turns of the head and the eyes contralateral to the left hemisphere have an inhibitory (if anything) effect on the REA.  相似文献   
959.
Coping with job stress and burnout in the human services   总被引:2,自引:0,他引:2  
A mail survey of 141 human service workers investigated the effects of coping on psychological strain and "burnout" produced by job stress. The survey assessed job stressors and coping strategies with open-ended questions and measured strain using closed-ended alienation, satisfaction, and symptom scales. Because previous research suggested that individual coping responses do not alleviate strain produced by job stress, the survey elicited information on group coping (social support) and on coping strategies initiated by agencies. Job stress was associated with high levels of strain, and group coping with low levels, but individual responses had little effect. Although workers identified many strategies that agencies could use to reduce stress and strain, actual use of such strategies was slight. Because men and women worked in the same jobs, no sex differences in individual coping were predicted and none were found; women, however, reported more social support than men. There was no evidence for moderating (interaction) effects of stress and coping on strain.  相似文献   
960.
Computer tomography (CT) is an important aid to the diagnosis of sella tumours because it images the tumour directly and delineates it from the healthy tissues. The tumour type can be identified to a certain extent, but angiography is necessary to distinguish tumours from aneurysms. The study is based on 140 surgical and histological examinations, the results of which were compared wit those obtained by CT. Suprasellar inflammations could always be identified by CT. Although intrasellar tumours may be identifiable by CT if full use is made of the potential of the equipment, negative CT results do not necessarily mean that there is no tumour. The diagnostic validity of the method is restricted by the absence of "standards", against which the variable images of intrasellar structures can be judged, and the restricted resolution of CT.  相似文献   
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