首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Measured the effects of early visual experience and later unilateral neocortical lesions on the behavior of 30 male hooded Long-Evans rats in an open-field, 17-arm spatial maze and on a visual field or perimetry test. 30 Ss were formed into 6 groups—3 light-reared (LR) and 3 dark-reared (DR)—of 5 Ss each in order to receive right-, left-hemisphere, or sham neocortical lesions. The comparison of behavior observed in the open field revealed that LR Ss with right-hemispheric lesions were more active and reared more than any of the other Ss. On the radial-maze task, in which 8 of 17 arms were baited, all Ss with lesions performed less effectively than did sham-operated Ss. The effect of the lesions was significantly greater for LR than for DR Ss. Perimetry testing revealed that, although the lesioned Ss did react to stimuli throughout their visual field, some contralateral neglect was evident in both LR and DR Ss; the lesions had a greater impact on orientation behavior of LR Ss, however. No evidence emerged of any functional asymmetry following the unilateral cortical lesions. Findings are discussed in terms of V. H. Denenberg's (1981) hypothesis about cerebral and functional asymmetry in the rat. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

2.
The hypothesis that psychosis-prone students demonstrate a pattern of exaggerated perceptual asymmetry across both left- and right-hemisphere dichotic-listening tasks (consonant-vowel [CV] and tonal contour discrimination) was investigated. Ss who scored high on the Perceptual Aberration or Magical Ideation scale or both (n?=?20) demonstrated a significantly exaggerated right-ear advantage on a CV task in relation to normal control Ss (n?=?27) but showed a reduced left-ear advantage on a tone task. The hypothesis of exaggerated functional lateralization across hemispheres in the psychosis-prone Ss was not supported, but the results are consistent with a hypothesis of left hemisphere overactivation in this sample. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
Tested the validity of findings by J. McGlone (1977) of a difference in the sexes in the cognitive sequelae of lateralized brain damage. The present study tested 28 male and 17 female patients with left and right hemisphere infarcts. Although Ss with left and right hemisphere infarcts showed differential impairment on measures of visual and verbal memory and on Performance scale IQ of the Wechsler Adult Intelligence Scale (WAIS), there were no differences between male and female Ss. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

4.
Studied discrete functional localization for visuo-perceptual, spatial, and nonverbal memory tasks in conjunction with focal electrical stimulation of the exposed right-dominant cortex during awake craniotomies in 22 patients. Results provide evidence for discrete functional localization in the right, nondominant hemisphere. Performance on each task was significantly impaired in association with stimulation of some, but not all, sites in comparison with performance on nonstimulation control trials. There was, generally, a strong dissociation of sites involved in separate functions across individual Ss. Contrary to the notion of diffuse functional organization in the nondominant hemisphere, visuospatial functions in the right hemisphere appear to be as discretely localized as verbal functions in the left hemisphere. Language and language-related functions of naming, reading, short-term verbal memory, nonverbal oral-facial movement, and phonemic identification were assessed in a subgroup of 10 Ss in conjunction with right nondominant cortical stimulation. In right-handed Ss, no disruptions of these tasks were seen with stimulation of sites outside the right face motor cortex itself. In 2 case studies, there was evidence for right cortical involvement in the mediation of 2 nonphonetic symbol-based language systems: Japanese Kanji and Fortran. (French abstract) (72 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
In order to evaluate the possible psychopathological symptomatology the authors analyzed the results of a clinico-dynamical observation of 176 patients in the acute period of a stroke. Among 128 patients with the right hemisphere localization of the focus (the main group) in 60 cases (47%) there were revealed psychopathological symptoms whereas in the control group (48 cases) with left hemispheric foci only 2 patients (4.2%) such disturbances were noted. The main expressions of psychopathological syndromes in patients with lesions of the right hemisphere were anosognosia, certain emotional reactions in the form of euphoria, a drop in purposeful activity, motor and mental aspontanity and specific confabulatory disorders. The qualitative and quantitative specificity of psychopathological syndromes in focal vascular lesions of the right hemisphere is supplementary material for further deep studies of the functional asymmetry of the brain hemispheres.  相似文献   

6.
Compared 9 male patients with Korsakoff's syndrome to 19 normal and 11 alcoholic control Ss on their threshold for recognition of words or patterns presented monocularly to the lateral visual fields. Ss were then tested on backward visual masking of the same (target) stimuli to determine the interstimulus interval (ISI) needed to escape the masking effect (critical ISI) in each lateral field. Threshold for recognition and critical ISI were elevated in Korsakoff Ss. For all Ss, the right visual field was superior to the left for word recognition but not for pattern recognition. The critical ISIs were shorter in the right visual field for both types of material, suggesting that the dominant hemisphere is more efficient in the early (iconic) stages of information processing. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
Examined the validity of the hypothesis that the 2 cerebral hemispheres are differentially sensitive to the outputs of the spatial-frequency channels, using 12 male right-handed adults. Ss viewed digitized broad-pass, digitized low-pass, and coarsely quantized photographs that were presented to the left or the right of their point of fixation and were required to identify the faces as male or female. Results indicate that low spatial-frequency photographs were processed more efficiently by the right than by the left hemisphere, while higher frequency components benefited the left more than the right hemisphere. Exposure duration, spatial-frequency content, and practice effects appeared to influence the respective processing efficiency of the cerebral hemispheres. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
9.
Hemispheric processing of visually presented words and pictures was examined in 3 groups of Ss with mean ages of 8 yrs 8 mo, 12 yrs 3 mo, and 27 yrs 9 mo (154 Ss). Pictorial or symbolic stimuli were presented singly to either the right or left visual hemifield. Ss had to decide whether the 1st stimulus in a pair matched the 2nd stimulus. The major results were that (a) age groups differed in the strength of lateral differences, and (b) for all age groups, the right hemisphere was significantly faster in processing unmatched stimuli. Results suggest that lateral specialization of the left hemisphere is not complete until adolescence and that over the age range tested, the left hemisphere becomes progressively more specialized for the processing of matched data. (52 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Two experiments, with 92 male Sprague-Dawley rats, examined the role of interhemispheric interaction in the production of spontaneous hyperactivity following right but not left frontal cortical suction lesions. Bilateral lesions, either simultaneous or left followed 1 wk later by right, led to spontaneous hyperactivity and bilateral depletions of cortical norepinephrine concentrations. Ss given corpus callosum sectioning as neonates and frontal cortical suction lesions as adults developed spontaneous hyperactivity only when the right hemisphere was injured. Data suggest that lateralized spontaneous hyperactivity as elicited by small suction lesions of the right hemisphere does not depend on interhemispheric release or interaction and that at least the cortical mechanism is in the right hemispere itself. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
Reports 2 experiments relating schizophrenia to functional brain asymmetry. In Exp I, 24 schizophrenics (mean age, 30.8 yrs) were compared to 24 matched controls (mean age, 37.3 yrs) on 2 tachistoscopic tasks (Syllable Test and Dot Location Test) designed to measure verbal and spatial information processing in the 2 hemispheres. Unlike the controls, the schizophrenics showed a right hemisphere superiority both on the verbal and on the spatial tests, indicating left hemisphere dysfunction in the initial processing of verbal information. In Exp II, lateral eye movements, as an index of contralateral hemispheric activation, were measured in a group of 24 paranoid schizophrenics (mean age, 28.9 yrs), 24 nonparanoid schizophrenics (mean age, 32.7 yrs), and 24 matched controls (mean age, 31.2 yrs). The eye movements were elicited by presenting the Ss with verbal neutral, verbal emotional, spatial neutral, and spatial emotional questions. The schizophrenics had significantly more rightward eye movement, compared to controls, regardless of question type, indicating left hemisphere overactivation. Results suggest that schizophrenia is associated with a pattern consisting of both left hemisphere dysfunction and overactivation. (63 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
Through the 30-day postoperative period following focal right hemisphere cortical suction lesions, lesioned and sham-operated control male Sprague-Dawley rats were placed in cold water for 5 min either 4 times at weekly intervals, once during the 1st postoperative week, or not at all. Results indicate different effects of the swim on lesioned and control Ss. Stress at weekly intervals produced hyperactivity in controls but weekly stress in lesioned Ss blocked the development of their expected hyperactivity. A single stress experience occurring 1 wk postoperatively was also sufficient to block the development of hyperactivity in lesioned Ss. Stress, although affecting behavior, did not alter the pattern of norepinephrine depletions in lesioned Ss. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
P. Green and other investigators have reported that schizophrenic Ss have poorer recall of stories presented to both ears than to the single best ear (binaural deficit) and poorer recall of stories presented to the left ear than to the right ear (monaural asymmetry) than do normal control Ss. These studies are plagued by potential methodological problems, including differences in overall accuracy, which artifactually affect the difference scores, and scoring methods that are vulnerable to systematic bias. In this study, scores of schizophrenic, bipolar, and normal control Ss on the Auditory Comprehension Test were compared. Scoring bias was avoided by the use of blind scoring and a revised scoring manual, and artifactual effects of accuracy were considered in interpreting the results. Contrary to previous findings, the groups did not differ on either monaural asymmetry or binaural deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
Studied the cognitive performance of 24 high and 36 low trait anxious undergraduates under conditions of high and low situational stress, using tasks requiring greater contribution of the right or left hemisphere. In addition, a perceptual task was adapted from visual information processing research to assess Ss' global or analytic approaches to perception; if anxiety increased the left hemisphere's contribution to perception, anxious Ss might be expected to be more analytic and detail oriented. Results show no significant differences on left hemisphere tasks but a significant interaction of trait by state anxiety for right hemisphere tasks: Low trait Ss performed better and high trait Ss performed more poorly under situational stress. Trait anxiety showed a significant main effect on visual information processing strategy, low Ss tending to be more global and high Ss tending to process the stimulus analytically. Results support the utility of a neuropsychological model in describing the effects of emotion on perception. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Examined auditory processing of linguistic stimulation presented dichotically to groups of 30 Down's Syndrome (DS) children, 20 non-DS retarded children who were MA and CA matched, and 20 MA matched nonretarded children, all of whom were right-handed. Ss completed a knowledge-of-numbers test and the Slosson Intelligence Test. They then listened to 20 trials of a dichotic message at approximately 70–75 db and repeated digits they heard. DS Ss showed a significant left ear advantage in processing the auditory linguistic material, while the other Ss showed the normal right ear advantage. Findings corroborate that having DS has a specific effect on the functional organization of the CNS auditory system. The right hemisphere may not be as efficient as the left hemisphere at language processing. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Investigated sex differences in the representation of visuospatial functions in the human brain in 20 Ss with right hemisphere stroke and 40 stroke-free control Ss with the Complex Figure Test, Wechsler Adult Intelligence Scale—Revised (WAIS—R) Block Design, and Judgment of Line Orientation. Also, 3 models of sex differences in the representation of visuospatial functions in the human brain were evaluated. The stroke and control groups were composed of equal proportions of men and women. Results suggest that women may be disproportionately impaired in visuospatial functioning relative to men following right hemisphere stroke. It is proposed that visuospatial functions were bilaterally represented in the brains of men, allowing them to rely upon left hemisphere visuospatial systems following right hemisphere stroke, and that these functions were represented in the right hemisphere of women, resulting in their disproportionate impairment despite comparable lesions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Assessed behavioral effects of unilateral frontocortical suction lesions in the right and left hemispheres in 24 male Sprague-Dawley rats, using a computerized activity monitoring system. Lesions of the right frontal cortex produced postoperative hyperactivity consisting of increases in the total distance traveled, average distance per movement, and average speed of movement. Vertical, rotational, and stereotypic measures were not changed. Ss receiving left hemisphere lesions did not differ from sham-operated controls on any behavioral variable. The lateralized hyperactivity resulting from lesions of the right frontal cortex was confined to increased length and speed of horizontal movement and did not appear to represent a generalized increase in all components of spontaneous activity. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Studied the behavior of 12 adult male and 12 adult female ring doves during the breeding period. The stages of female mating responsiveness were defined by characteristic behavioral events (e.g., approaching, nest soliciting, nest crouching, and nest building). In Exp. I, 24 females had their left (functional) ovary completely or partially removed or received sham operations. Sinistrally ovariectomized Ss lost their characteristic behavior patterns in response to courting: Their behaviors were regressed to that of the nonresponsive stage, where sleeping, perching, and other self-directed activities are the dominant behavior patterns. The characteristic responsive behavior patterns were recovered in some Ss as the right rudimentary ovary regenerated. In Exp. II with 25 female Ss, a 2-stage bilateral ovariectomy entirely abolished any chance of behavioral recovery. Results verify the role of ovarian hormones in female reproductive behavior in ring doves. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
Examined auditory perceptual asymmetries and explicit memory biases for threat in patients with panic disorder and generalized anxiety disorder relative to healthy control Ss. They did not find a greater explicit memory bias for threat in the anxiety patients. However, explicit memory biases for threat were associated with perceptual asymmetry scores; patients with a greater right-ear (left hemisphere) advantage exhibited an explicit memory bias for threat material, whereas patients with a lower right-ear advantage displayed apparent cognitive avoidance of threat material. Memory for threat words was unrelated to perceptual asymmetry in healthy control Ss. These findings suggest that neuropsychological variables may partly determine the degree to which anxiety patients process threatening stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
Discusses the theory that asserts that the residual reading abilities seen in deep dyslexia entirely reflect the operation of an intact right hemisphere reading system rather than a partially disabled left hemisphere reading system. Evidence from an experiment with normal Ss in a report by the present author and colleagues (1983) is presented, which suggests that the right hemisphere contains no lexical entries for abbreviations that can be accessed by visual presentation. Data are presented from studies by K. E. Patterson (1980; see also PA, Vols 63:12203 and 64:10691) on 2 male deep dyslexic's understanding of printed abbreviations, along with observations of a young female deep dyslexic who was tested on understanding of abbreviations and on letter-naming abilities. Considerable sparing of the ability to obtain semantic information from printed abbreviations was evidenced in all 3 Ss. This contrast suggests that the current right hemisphere account of the residual reading abilities seen in deep dyslexia is not a sufficient one and should be modified. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号