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1.
We report on a 50-year-old man with mental retardation and right-sided hemi-paresis. He seemed to be cured from epilepsy. In a short time a mental and physical deterioration developed which looked like a dementia, which was suggested by vascular risk factors. The EEG showed marked epileptic activity characterized by spikes appearing every 10 seconds over the left temporal lobe. After introduction of carbamazepine, a fast and long-term improvement of symptoms was noticed resulting in self sufficiency. The fast and marked effect of an antiepileptic drug being given to the patient with an non-typical reactivation of epilepsy in which the dementia-syndrome was caused by a transitory cognitive impairment due to sub-clinic electric seizures or non-convulsive status epilepticus.  相似文献   

2.
We aimed to investigate the effect of hand effector and handedness on the cerebral lateralization of pantomiming learned movements. Fourteen right-handed and 14 left-handed volunteers performed unimanual and bimanual tool-use pantomimes with their dominant or nondominant hand during fMRI. A left hemispheric lateralization was observed in the right- and left-handed group regardless of which hand(s) performed the task. Asymmetry was most marked in the dorsolateral prefrontal cortex (DLPFC), premotor cortex (PMC), and superior and inferior parietal lobules (SPL and IPL). Unimanual pantomimes did not reveal any significant differences in asymmetric cerebral activation patterns between left- and right-handers. Bimanual pantomimes showed increased left premotor and posterior parietal activation in left- and right-handers. Lateralization indices (LI) of the 10% most active voxels in DLPFC, PMC, SPL, and IPL were calculated for each individual in a contrast that compared all tool versus all control conditions. Left-handers showed a significantly reduced overall LI compared with right-handers. This was mainly due to diminished asymmetry in the IPL and SPL. We conclude that the recollection and pantomiming of learned gestures recruits a similar left lateralized activation pattern in right and left-handed individuals. Handedness only influences the strength (not the side) of the lateralization, with left-handers showing a reduced degree of asymmetry that is most readily observed over the posterior parietal region. Together with similar findings in language and visual processing, these results point to a lesser hemispheric specialization in left-handers that may be considered in the cost/benefit assessment to explain the disproportionate handedness polymorphism in humans.  相似文献   

3.
The mechanism by which most people favor use of the right hand remains unknown. It has been proposed that asymmetries in the nigrostriatal dopamine system may be related to motor lateralization in humans. We explored this hypothesis in vivo by using [18F]fluorodopa positron emission tomography. Whereas the degree of right hand preference was found to correlate with left putamen dominance as assessed by asymmetry in fluorodopa uptake (K(i)), right caudate dominance was positively correlated with the level of performance during simultaneous bimanual movements in right-handed normal subjects. In addition, right-handed patients with Parkinson's disease with higher right than left caudate K(i) performed much better in bimanual movement tests than those in whom the K(i) value of the left caudate was higher than that of the right. These findings support the notion that the nigrostriatal dopaminergic system may play a role in motor lateralization, and suggest a functional model for bimanual movements. We propose that the skill for performing simultaneous bilateral hand movements in right-handed subjects might depend upon both the activation (through the dominant left putamen circuitry) of the left supplementary motor area (SMA), and the inhibition (through the right caudate circuitry) of motor programs stored in the right SMA.  相似文献   

4.
Masked depression refers to a concept of a phenomenological state, either endogenous or psychogenic where somatic symptoms replace sadness: Thirty patients were evaluated by RDC (22 endogenous and 8 masked depressions) wherein in the latter dysphoria was replaced by a nonreactive persistent somatic complaint. They were rated on Beck and Hamilton Depression Scales, on Hamilton and Trait-State Anxiety Scales and the NOSIE. All patients presented with insomnia, anorexia, loss of weight, diminished libido and anhedonia. Initial ratings were similar for both diagnostic groups except for a significantly higher agitation factor and lower retardation in masked depression. Although 59.9 percent of the subjects are positive on the dexamethasone test, only 1 masked depression did not suppress secretion of cortisol. After a randomized 30-day drug trial where patients were assigned to Clomipramine or Desipramine, patients in both groups show significant improvement on rating scales but diagnostic group drug treatment interaction exists on anxiety and agitation criteria.  相似文献   

5.
Previous event-related potential (ERP) studies have revealed that faces and words show a robust difference in the lateralization of their N170. The present study investigated the development of this differential lateralization in school-age boys. We assessed the potential role of fetal testosterone (FT) level as a factor biasing the prenatal development of lateralization, and the role of reading skill and Verbal IQ as factors predicting left lateralization for words in childhood. The adult pattern of differential N170 lateralization for faces and words was not present in a group of 26 school-age boys. This suggests that N170 lateralization only appears with years of experience with these stimulus categories or with late childhood maturation. FT level measured by amniocentesis did not account for a significant part of the individual variability in lateralization. Verbal IQ correlated with the degree of left lateralization of the N170 to words, but this effect was not specific to language abilities and language lateralization. A strong correlation was observed between the degree of left lateralization for words and the degree of left lateralization for faces, and both lateralization scores correlated with Verbal and Performance IQ. Possible explanations for these results are discussed along with ERP correlates of words and faces in school-age boys.  相似文献   

6.
Movement asymmetry in humans and animals is often considered as being induced by the brain lateralization of the motor system. In the present work, the hemispheric asymmetry for motor planning as a cause of behavioral lateralization was examined. This study was carried out on normal volunteers and patients suffering unilateral brain damage caused by a stroke. Motor planning was evaluated by using the motor imagery of hand movement, a mental representation of a motor pattern that includes its internal simulation but not its real execution. The present study shows marked similarities between virtual movement executed during motor imagery and real movements. Thus, performance time showed a high correlation between real and virtual movements in the following conditions: (1) during dominant and non-dominant hand movements; (2) in simple and complex motor tasks; (3) in young control subjects; (4) in stroke patients; and (5) control subjects aged-matched to stroke patients. Brain strokes increased the performance time in both real and virtual movements. Left-brain strokes decreased the velocity of the real movements in both hands, whereas right-brain strokes mainly disturbed movements in the left hand. A similar effect was observed for virtual movements, suggesting a left-brain dominance for motor planning in humans. However, two-handed movement tasks suggest a complex interaction during motor planning, an interaction that facilitates motor performance during mirror movements and delays motor execution during non-mirror movements.  相似文献   

7.
Limb preference and reaching success were examined in 580 Long-Evans rats. Most rats displayed a strong asymmetry. Although slightly more rats used the left limb than used the right limb, the difference was not significant. Thus, Long-Evans rats do not show dominance with respect to limb use. There was a significant correlation between the degree of lateralization and success of limb use. This relation suggests either that endogenous factors contributing to limb lateralization also contribute to motor skill or else the use of a lateralized reaching strategy facilitates the development of skill in reaching. The results are discussed in terms of their methodological implications for studies of selective breeding and strain differences and also in terms of their significance for understanding the evolutionary basis of lateralization and dominance.  相似文献   

8.
To study hemispheric lateralization of cortical potentials associated with motoric and non-motoric function, cortical activity was recorded accompanying either finger extension or saccadic eye movements in a contingent negative variation (CNV) paradigm. Subjects viewed computer-generated pacing stimuli, presented in the left visual hemi-field, and were instructed to either initiate or inhibit a motor response following an imperative signal. Motoric lateralization was assessed by means of the lateralized readiness potential (LRP). In addition, a measure complementary to the LRP was introduced to investigate non-motoric lateralization (NML). Contralateral inter-hemispheric lateralization was evident in the LRP preceding finger movement, but was absent prior to eye movements. However, pre-saccadic cortical response profiles did exhibit a right hemispheric, non-motoric lateralization (NML) during stimulus presentation. Comparable non-motoric lateralization was found for finger extension. Results of the present study suggest that non-motoric lateralization may be a contributing factor to the frequently reported inter-hemispheric asymmetry preceding self-initiated saccadic eye movements. Results of the present study also suggest that the latter may be related to a covert shift of visuospatial attention toward the saccadic target. Associated shifts of attention are suppressed in a CNV paradigm, where attentional focus is primarily on the CNV stimulus during the pre-saccade period.  相似文献   

9.
Psychomotor symptoms related to an impairment of the nigrostriatal dopaminergic system are frequent in major depression (MD). Repetitive transcranial magnetic stimulation (rTMS) has been discussed as a new treatment option for MD. In neurobiological terms, an influence of high-frequency rTMS on dopaminergic neurotransmission has previously been shown by several studies in animals and humans. Therefore, an improvement of psychomotor symptoms by rTMS could be assumed. The aim of this pilot study was to investigate the effect of high-frequency rTMS on psychomotor retardation and agitation in depressive patients. We investigated the effect of left prefrontal 10 Hz rTMS on psychomotor retardation and agitation in 30 patients with MD. Patients were randomly assigned to real or sham rTMS in addition to a newly initiated standardized antidepressant medication. We found a trend in the reduction of agitation (t 28 = 1.76, p = 0.09, two-tailed), but not in the reduction of retardation. Furthermore, no general additional antidepressant effect of rTMS was observed. Although there was no statistical significant influence of high-frequency rTMS on psychomotor symptoms in depressive patients, the results showed a trend in the reduction of psychomotor agitation in MD. This effect should be systematically investigated as the primary end point in further studies with larger sample sizes.  相似文献   

10.
Patients with anarchic hand (AH) syndrome exhibit involuntary but seemingly purposeful controlesional upper limb movements. Here we report on the case of a patient (AC) presenting with a right AH following a left medial frontal lesion. Previous literature indicated that endogenous movements, particularly in the presence of distractors, are impaired in AH, whereas exogenous movements are spared. In this study we examined exogenous and endogenous (or sequential) movements using a new experimental procedure. Our main aim was to investigate whether the ability to perform sequential movements improves under verbal command as anecdotally observed in patients with AH. Results showed that the performance of AC's right AH was impaired in sequential tasks and that this impairment was improved by verbal command. The observed reduction in errors in sequential tasks under external verbal command was coupled with a compensatory increase in response times.  相似文献   

11.
Using H2 15O positron emission tomography in 6 healthy volunteers, we found that self-initiated and externally cued blinking activated the right primary motor cortex and supplementary motor area (SMA). The left dorsolateral prefrontal cortex (DLPFC) and the rostral SMA showed greater activation during the self-initiated task compared to the externally cued task. This study confirms the hypothesis of right hemispheric lateralization of volitional blinking derived from observations in stroke patients. Furthermore, it underscores the role of DLPFC and rostral SMA in self-initiated movements, which has been found in similar experiments with hand movements.  相似文献   

12.
Previous studies have demonstrated that following unilateral stroke, motor impairment occurs both contralateral, as well as ipsilateral, to the lesion. Although ipsilesional impairments can be functionally limiting, they can also provide important insight into the role of the ipsilateral hemisphere in controlling movement and the lateralization of specific motor control mechanisms, given that unilateral arm movements are thought to recruit processes in each hemisphere. The purpose of this study was to examine whether left and right hemisphere damage following stroke produces different ipsilesional deficits, and whether our dynamic dominance model of motor lateralization can predict such deficits. Specifically, the dynamic dominance model attributes control of multijoint dynamics to the left hemisphere, and control of steady-state position to the right hemisphere. Chronic stroke patients with either left or right hemisphere damage (LHD or RHD) used their ipsilesional arm, and the control subjects used either their left or right arm (LHC or RHC), to perform targeted reaching movements in different directions within the workspace ipsilateral to their reaching arm. We found that the LHD group showed deficits in controlling the arm's trajectory due to impaired multijoint coordination, but no deficits in achieving accurate final positions. In contrast, the RHD group showed deficits in final position accuracy but not in the ability to coordinate multiple joints during movement, thereby providing additional evidence for the hemisphere-specific nature of motor deficits. Furthermore, while both the LHD and RHD groups were functionally impaired to the same degree on the Jebsen Hand Function Test (JHFT), our results suggest that the underlying mechanisms for such impairment may be hemisphere-dependent.  相似文献   

13.
The epileptic discharge of one hemisphere interferes with brain function. The present study assesses the linguistic disabilities of epileptic patients owing to discharge in one hemisphere. Subjects were classified by age and gender. A significant deterioration of linguistic abilities appeared in adult subjects discharging in the left hemisphere. In children, however, a more symmetric hemispheric pattern of epileptic discharge interference appears with age up to 14 years. Unihemispheric epileptic discharges could also provide information about the degree of lateralization that a given function presents in different developmental stages. This lateralization appears clearly established from the age of 14 to 21 years until late adulthood. These results imply that hemispheric specialization of language is not completed until adolescence. This absence of hemispheric specialization for language in childhood was statistically more significant in boys than in girls, suggesting that the maturation of cortical areas related to language occurs earlier in girls than in boys. Finally, the familial history of left-handedness is a factor delaying the age of left lateralization of language in right-handed children.  相似文献   

14.
BACKGROUND: Kraepelin's partial interpretation of agitated depression as a mixed state of "manic-depressive insanity" (including the current concept of bipolar disorder) has recently been the focus of much research. This paper tested whether, how, and to what extent both psychomotor symptoms, agitation and retardation in depression are related to bipolarity and anxiety. METHOD: The prospective Zurich Study assessed psychiatric and somatic syndromes in a community sample of young adults (N = 591) (aged 20 at first interview) by six interviews over 20 years (1979-1999). Psychomotor symptoms of agitation and retardation were assessed by professional interviewers from age 22 to 40 (five interviews) on the basis of the observed and reported behaviour within the interview section on depression. Psychiatric diagnoses were strictly operationalised and, in the case of bipolar-II disorder, were broader than proposed by DSM-IV-TR and ICD-10. As indicators of bipolarity, the association with bipolar disorder, a family history of mania/hypomania/cyclothymia, together with hypomanic and cyclothymic temperament as assessed by the general behavior inventory (GBI) [15], and mood lability (an element of cyclothymic temperament) were used. RESULTS: Agitated and retarded depressive states were equally associated with the indicators of bipolarity and with anxiety. Longitudinally, agitation and retardation were significantly associated with each other (OR = 1.8, 95% CI = 1.0-3.2), and this combined group of major depressives showed stronger associations with bipolarity, with both hypomanic/cyclothymic and depressive temperamental traits, and with anxiety. Among agitated, non-retarded depressives, unipolar mood disorder was even twice as common as bipolar mood disorder. CONCLUSION: Combined agitated and retarded major depressive states are more often bipolar than unipolar, but, in general, agitated depression (with or without retardation) is not more frequently bipolar than retarded depression (with or without agitation), and pure agitated depression is even much less frequently bipolar than unipolar. The findings do not support the hypothesis that agitated depressive syndromes are mixed states. LIMITATIONS: The results are limited to a population up to the age of 40; bipolar-I disorders could not be analysed (small N).  相似文献   

15.
Functional hemispherectomy is an accepted treatment in hemispherical intractable epilepsy syndromes. We report a patient who had functional hemispherectomy for intractable seizures secondary to right hemispheric cortical dysplasia. Preoperatively, the patient had mild left hemiparesis and functional magnetic resonance imaging (fMRI) showed bilateral motor function lateralization to normal left hemisphere. The patient remains seizure free at 1-year follow-up, with no deterioration of motor power on left side. This report reviews physiology of neural plasticity for motor function lateralization and also reliability of fMRI in determining the functional shift.  相似文献   

16.
Based on earlier clinical experiences a group of 52 nonmigrainous depressed women were treated with 3-6 mh/day pizotifene (Sandomigran-Sandoz) in order to evaluate a presumed antidepressant action. The Bunney-Hamburg behavior-rating scale was employed to quantify the results. Thirteen patients showed marked improvement and 22 patients partial improvement after three weeks' treatment. Involutional and psychoreactive depressions responded better than endogenous forms. Symptomatically, anxiety and dysphoria were significantly more favorably influenced than retardation or paranoia. No serious side effects were observed.  相似文献   

17.
We investigated the lateralization of brain activity pattern during performance of unilateral movement in drug‐naïve Parkinson's disease (PD) patients with only right hemiparkinsonian symptoms. Functional MRI was obtained when the subjects performed strictly unilateral right hand movement. A laterality index was calculated to examine the lateralization. Patients had decreased activity in the left putamen and left supplementary motor area, but had increased activity in the right primary motor cortex, right premotor cortex, left postcentral gyrus, and bilateral cerebellum. The laterality index was significantly decreased in PD patients compared with controls (0.41 ± 0.14 vs. 0.84 ± 0.09). The connectivity from the left putamen to cortical motor regions and cerebellum was decreased, while the interactions between the cortical motor regions, cerebellum, and right putamen were increased. Our study demonstrates that in early PD, the lateralization of brain activity during unilateral movement is significantly reduced. The dysfunction of the striatum–cortical circuit, decreased transcallosal inhibition, and compensatory efforts from cortical motor regions, cerebellum, and the less affected striatum are likely reasons contributing to the reduced motor lateralization. The disruption of the lateralized brain activity pattern might be a reason underlying some motor deficits in PD, like mirror movements or impaired bilateral motor coordination. Hum Brain Mapp 36:1878–1891, 2015. © 2015 Wiley Periodicals, Inc .  相似文献   

18.
Psychomotor retardation (PR) is among the most important features of depression. This study investigates the development of day- and night-time as well as intensity and quantity of circadian motor activity during a 4-week course of treatment among 27 patients with depression compared to 27 healthy controls. A diagnosis of major depression was made using SCID. Motor activity was continuously measured with an actigraph during the study and clinical course of depression with HAM-D-21. Motor activity was described as the quantity and intensity of movements during day- and night- time. Clinically improved patients had significantly intensified movements after 4 weeks, compared to subjects with <50% improvement on HAM-D. While the measures of day-time level of movements captured the clinical improvement of depression, clinical improvement was not reflected by the night-time measurements. This study demonstrates that the separated analysis of level and quantity of movements supports a better understanding of the nature of psychomotor retardation during depression. The subdivision in day- and night-time activity objectively measured with actigraphy captures distinct patterns of motor activity and represents prognostic factors in the treatment outcome of depression. The study also highlights the importance of studying the intensity of movements separately from the quantity of movements in relation to treatment outcome.  相似文献   

19.
Summary Based on earlier clinical experiences a group of 52 nonmigrainous depressed women were treated with 3–6mg/day pizotifene (Sandomigran-Sandoz) in order to evaluate a presumed antidepressant action. The Bunney-Hamburg behavior-rating scale was employed to quantify the results. Thirteen patients showed marked improvement and 22 patients partial improvement after three weeks' treatment. Involutional and psychoreactive depressions responded better than endogenous forms. Symptomatically, anxiety and dysphoria were significantly more favorably influenced than retardation or paranoia. No serious side effects were observed.  相似文献   

20.
A case of agitated catatonia   总被引:1,自引:0,他引:1  
Agitation is one of the diagnostic features of catatonia in the DSM IV classification, but permanent forms of agitated catatonia have occasionally been described. We report the case of a 43-year-old man who had already suffered from undifferentiated schizophrenia for 7 years, and in whom we diagnosed agitated catatonia. While our patient was being treated with a neuroleptic during a second episode of paranoia, a state of agitation was observed which persisted for a further 8 months. During this period, he was treated with several different neuroleptics and benzodiazepines, either alone or in association, without any improvement. No organic cause was found. He was then transferred to our electroconvulsive therapy (ECT) unit, with a diagnosis of schizophrenic agitation resistant to drug therapy. ECT was begun, and he was only given droperidol in case of agitation and alimemazine for insomnia, neither of which had any effect. In view of his persistent agitation without any purpose, echolalia and echopraxia, stereotyped movements with mannerisms and marked mimicking and grimacing, we diagnosed him as having agitated catatonia. After the fourth session of ECT, we decided to stop all treatment and gave him lorazepam at a dose of 12.5 mg daily. Twenty-four hours later, all symptoms of agitation had disappeared. In our opinion, permanent catatonic agitation is not rare. In our case, the neuroleptic treatment maintained and may even have worsened the symptomatology. Lorazepam can be used as a therapeutic test for this type of agitation, especially if it does not respond to neuroleptics. This also allows the patient to be sedated rapidly and effectively, thus preventing him from injuring himself further.  相似文献   

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