运动想象治疗脑卒中患者手部运动功能的功能磁共振研究

目的：探讨运动想象（MI）治疗对脑卒中后脑功能重塑的影响。方法：将16例脑卒中患者随机分为运动想象组（MI）6例、执行运动（EM）组5例、对照组（CG）5例。3组在常规康复治疗基础上,MI组、EM组分别进行运动想象、实际动作治疗,每次30min,每周5次,为期4周。治疗前、后进行运动功能评价,并使用功能磁共振（fMRI）观察患手对指实际动作、想象时偏瘫对侧感觉运动区的激活情况,定量分析治疗前后cSMC区的激活强度t、LI变化。结果：治疗4周后,MI组及EM组FMA、STEF评分较前均有明显提高（均P＜0.05）,且MI组上述评分均更高于其它2组（均P＜0.05）。治疗后,3组MBI评分均有提高,但组内及组间差异无统计学意义。运动想象与运动执行的激活部位相似：治疗前运动想象激活区主要位于双侧SMC区、双侧SMA区,治疗后,各组双侧SMC区激活强度有增大趋势,MI组对侧SMC区激活显著（P＜0.05）,且对侧偏侧化优势较CG组显著（P＜0.05）。结论：运动想象治疗能够明显改善脑卒中后患者手功能,其机制可能与运动想象促进脑功能重塑有关。     

运动想象治疗脑卒中患者手部运动功能的疗效研究

目的:探讨运动想象(MI)疗法的可行性及有效性,总结适合脑卒中后偏瘫患者的训练方案。方法:将16例脑卒中偏瘫患者随机分为运动想象组(MI)6例、执行运动(EM)组5例、空白组(CG)5例。MI组给予运动想象治疗,EM组进行动作的实际操作训练,CG组仅进行常规康复治疗。使用简易上肢机能检查(STEF)、Fugl-Meyer上肢功能检查(FMA)、改良巴氏指数(MBI)评价患者训练前后的上肢运动功能、日常生活活动能力检查。结果:治疗4周后,MI组及EM组上肢FMA、STEF、评分较训练前及CG组训练后均有明显提高(P0.05),且MI改善更优于EM组(P0.05)。治疗4周后,3组MBI评分组内及组间比较差异均无统计学意义。结论:运动想象结合手部运动疗法对患手运动功能的提高比常规训练有更显著的优势。     

Gender differences in patient perceptions of involvement in myocardial infarction care

Background

Gender differences in the clinical presentation, treatment and outcomes of myocardial infarction (MI) have been demonstrated. However, few studies have examined gender differences in patients' perceptions of involvement in MI care, and whether differing levels of involvement might be associated with gender differences in treatment and outcome.

Aim

To examine possible gender differences in MI patients' perceptions of their involvement during hospitalization.

Methods

Questionnaire study conducted in 2005-2006 among MI patients under the age of 75 at eleven hospitals. Patient ratings of their involvement during hospitalization were analyzed for age-stratified gender differences.

Results

Younger (< 70 years of age) female MI patients placed significantly more value on shared decision-making than younger (< 70) men. More than one third of patients would have liked to be more involved in their care during hospitalization and discharge planning, with women significantly more dissatisfied than men. Significantly fewer younger female patients discussed secondary preventive lifestyle changes with cardiology staff prior to hospital discharge.

Conclusion

Significant age-specific gender differences exist in MI patient ratings of, and satisfaction with, involvement during hospitalization. Further study is needed regarding the possible role of involvement in the recognized gender differences in the treatment and outcomes of MI.     

The Occupational Risk of Motor Vehicle Collisions for Emergency Medicine Residents

OBJECTIVE: To determine the prevalence and risk factors associated with motor vehicle collisions (MVCs) and near-crashes as reported by emergency medicine (EM) residents following various ED shifts. METHODS: A survey was sent to all allopathic EM-2-EM-4 residents in May 1996 asking whether they had ever been involved in an MVC or near-crash while driving home after an ED shift. The residents' night shift schedules, self-reported tolerance of night work, ability to overcome drowsiness, sleep flexibility, and morningness/eveningness tendencies also were collected. RESULTS: Seventy-eight programs participated and 62% of 1,554 eligible residents returned usable surveys. Seventy-six (8%, 95% CI = 6% to 10%) residents reported having 96 crashes and 553 (58%, 95% CI = 55% to 61%) residents reported being involved in 1,446 near-crashes. Nearly three fourths of the MVCs and 80% of the near-crashes followed the night shift. Stepwise logistic regression of all variables demonstrated a cumulative association (R = 0.19, p = 0.0004) that accounted for 4% of the observed variability in MVCs and near-crashes. Univariate analysis showed that MVCs and near-crashes were inversely related to residents' shiftwork tolerance (p = 0.019) and positively related to the number of night shifts worked per month (p = 0.035). CONCLUSIONS: Residents reported being involved in a higher number of MVCs and near-crashes while driving home after a night shift compared with other shifts. Driving home after a night shift appears to be a significant occupational risk for EM residents.     

Distinct striatal regions for planning and executing novel and automated movement sequences

The basal ganglia-thalamo-cortical circuits are viewed as segregated parallel feed back loops crucially involved in motor control, cognition, and emotional processing. Their role in planning novel, as compared to overlearned movement patterns is as yet not well defined. We tested for the involvement of the associative striatum (caudate/anterior putamen) in the generation of novel movement patterns, which is a critical cognitive requirement for non-routine motor behavior. Using event related functional MRI in 14 right-handed male subjects, we analyzed brain activity in the planning phase of four digit finger sequences. Subjects either executed a single overlearned four digit sequence (RECALL), or self-determined four digit sequences of varying order (GENERATE). In both conditions, RECALL and GENERATE, planning was associated with activation in mesial/lateral premotor cortices, motor cingulate cortex, superior parietal cortex, basal ganglia, insula, thalamus, and midbrain nuclei. When contrasting the planning phase of GENERATE with the planning phase of RECALL, there was significantly higher activation within this distributed network. At the level of the basal ganglia, the planning phase of GENERATE was associated with differentially higher activation located specifically within the associative striatum bilaterally. On the other hand, the execution phase during both conditions was associated with a shift of activity towards the posterior part of the putamen. Our data show the specific involvement of the associative striatum during the planning of non-routine movement patterns and illustrate the propagation of activity from rostral to dorsal basal ganglia sites during different stages of motor processing.     

Cerebral correlates of motor imagery of normal and precision gait

We have examined the cerebral structures involved in motor imagery of normal and precision gait (i.e., gait requiring precise foot placement and increased postural control). We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined walking along paths of two different widths (broad, narrow) that required either normal gait, or exact foot placement and increased postural control. We used a matched visual imagery (VI) task to assess the motor specificity of the effects, and monitored task performance by recording imagery times, eye movements, and electromyography during scanning. In addition, we assessed the effector specificity of MI of gait by comparing our results with those of a previous study on MI of hand movements. We found that imagery times were longer for the narrow path during MI, but not during VI, suggesting that MI was sensitive to the constraints imposed by a narrow walking path. Moreover, MI of precision gait resulted in increased cerebral activity and effective connectivity within a network involving the superior parietal lobules, the dorsal precentral gyri, and the right middle occipital gyrus. Finally, the cerebral responses to MI of gait were contiguous to but spatially distinct from regions involved in MI of hand movements. These results emphasize the role of cortical structures outside primary motor regions in imagining locomotion movements when accurate foot positioning and increased postural control is required.     

Functional neuroanatomical networks associated with expertise in motor imagery

Although numerous behavioural studies provide evidence that there exist wide differences within individual motor imagery (MI) abilities, little is known with regards to the functional neuroanatomical networks that dissociate someone with good versus poor MI capacities. For the first time, we thus compared, through functional magnetic resonance imaging (fMRI), the pattern of cerebral activations in 13 skilled and 15 unskilled imagers during both physical execution and MI of a sequence of finger movements. Differences in MI abilities were assessed using well-established questionnaire and chronometric measures, as well as a new index based upon the subject's peripheral responses from the autonomic nervous system. As expected, both good and poor imagers activated the inferior and superior parietal lobules, as well as motor-related regions including the lateral and medial premotor cortex, the cerebellum and putamen. Inter-group comparisons revealed that good imagers activated more the parietal and ventrolateral premotor regions, which are known to play a critical role in the generation of mental images. By contrast, poor imagers recruited the cerebellum, orbito-frontal and posterior cingulate cortices. Consistent with findings from the motor sequence learning literature and Doyon and Ungerleider's model of motor learning [Doyon, J., Ungerleider, L.G., 2002. Functional anatomy of motor skill learning. In: Squire, L.R., Schacter, D.L. (Eds.), Neuropsychology of memory, Guilford Press, pp. 225-238], our results demonstrate that compared to skilled imagers, poor imagers not only need to recruit the cortico-striatal system, but to compensate with the cortico-cerebellar system during MI of sequential movements.     

Functional cerebral reorganization following motor sequence learning through mental practice with motor imagery

The goal of the present study was to examine, via positron emission tomography, the functional changes associated with the learning of a sequence of foot movements through mental practice with motor imagery (MI). Following intensive MI training over several days, which led to a modest but significant improvement in performance, healthy subjects showed an increase in activity restricted to the medial aspect of the orbitofrontal cortex (OFC), and a decrease in the cerebellum. These main results are largely consistent with those found in a previous study of sequence learning performed in our laboratory after physical practice of the same task [NeuroImage 16 (2002) 142]. Further analyses showed a positive correlation between the blood flow increase in the OFC and the percentage of improvement on the foot sequence task. Moreover, the increased involvement of the medial OFC revealed a modality specific anatomo-functional organization, as imagination of the sequential task after MI practice activated a more posterior region than its execution. These results demonstrate that learning a sequential motor task through motor imagery practice produces cerebral functional changes similar to those observed after physical practice of the same task. Moreover, the findings are in accord with the hypothesis that mental practice with MI, at least initially, improves performance by acting on the preparation and anticipation of movements rather than on execution per se.     

The role of higher-order motor areas in voluntary movement as revealed by high-resolution EEG and fMRI

In the human motor cortex structural and functional differences separate motor areas related to motor output from areas essentially involved in higher-order motor control. Little is known about the function of these higher-order motor areas during simple voluntary movement. We examined a simple finger flexion movement in six healthy subjects using a novel brain-imaging approach, integrating high-resolution EEG with the individual structural and functional MRI. Electrical source reconstruction was performed in respect to the individual brain morphology from MRI. Highly converging results from EEG and fMRI were obtained for both executive and higher-order motor areas. All subjects showed activation of the primary motor area (MI) and of the frontal medial wall motor areas. Two different types of medial wall activation were observed with both methods: Four of the subjects showed an anterior type of activation, and two of the subjects a posterior type of activation. In the former, activity started in the anterior cingulate motor area (CMA) and subsequently shifted its focus to the intermediate supplementary motor area (SMA). Approximately 120 ms before the movement started, the intermediate SMA showed a drop of source strength, and simultaneously MI showed an increase of source strength. In the posterior type, activation was restricted to the posterior SMA. Further, three of the subjects investigated showed activation in the inferior parietal lobe (IPL) starting during early movement preparation. In all subjects showing activation of higher-order motor areas (anterior CMA, intermediate SMA, IPL) these areas became active before the executive motor areas (MI and posterior SMA). We suggest that the early activation of the anterior CMA and the IPL may be related to attentional functions of these areas. Further, we argue that the intermediate part of the SMA triggers the actual motor act via the release of inhibition of the primary motor area. Our results demonstrate that a noninvasive, multimodal brain imaging technique can reveal individual cortical brain activity with high temporal and spatial resolution, independent of a priori physiological assumptions.     

Alpha1-adrenoceptors mediate dihydroxyphenylalanine-induced activity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned macaques

The mechanisms underlying actions of dihydroxyphenylalanine (L-DOPA) in Parkinson's disease remain to be fully elucidated. Noradrenaline formed from L-DOPA may stimulate alpha(1)-adrenoceptors. We assessed the involvement of alpha(1)-adrenoceptors in actions of L-DOPA in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned macaques. In each animal, the minimal dose of L-DOPA required to alleviate parkinsonian symptoms was defined (12.5-25 mg/kg p.o.). The effects of coadministration of the alpha(1)-adrenoceptor antagonist prazosin ([4-(4-amino-6,7-dimethoxy-quinazolin-2-yl) piperazin-1-yl]-(2-furyl)methanone) on motor activity, parkinsonism, and dyskinesia were assessed. Antiparkinsonian benefit was accompanied by mild dyskinesia. L-DOPA also elicited hyperactivity, i.e., activity greater than that seen in normal animals. Coadministration of prazosin (0.16-0.63 mg/kg p.o.) with L-DOPA did not significantly affect either its antiparkinsonian actions or dyskinesia. However, prazosin significantly and dose-dependently attenuated L-DOPA-induced activity, reducing it to a level equivalent to that of normal animals. More specifically, during periods of pronounced L-DOPA-induced activity, prazosin attenuated the total and duration of activity by 80 and 76%, respectively. These actions of prazosin were expressed in the absence of sedation. Although activation of alpha(1)-adrenoceptors plays no major role in the antiparkinsonian and dyskinetic effects of L-DOPA per se, it does contribute to the induction of hyperactivity. alpha(1)-Adrenoceptors may be involved in pathological responses to L-DOPA treatment, including the dopamine dysregulation syndrome.     

Neural Dynamics of Learning Sound—Action Associations

A motor component is pre-requisite to any communicative act as one must inherently move to communicate. To learn to make a communicative act, the brain must be able to dynamically associate arbitrary percepts to the neural substrate underlying the pre-requisite motor activity. We aimed to investigate whether brain regions involved in complex gestures (ventral pre-motor cortex, Brodmann Area 44) were involved in mediating association between novel abstract auditory stimuli and novel gestural movements. In a functional resonance imaging (fMRI) study we asked participants to learn associations between previously unrelated novel sounds and meaningless gestures inside the scanner. We use functional connectivity analysis to eliminate the often present confound of ‘strategic covert naming’ when dealing with BA44 and to rule out effects of non-specific reductions in signal. Brodmann Area 44, a region incorporating Broca's region showed strong, bilateral, negative correlation of BOLD (blood oxygen level dependent) response with learning of sound-action associations during data acquisition. Left-inferior-parietal-lobule (l-IPL) and bilateral loci in and around visual area V5, right-orbital-frontal-gyrus, right-hippocampus, left-para-hippocampus, right-head-of-caudate, right-insula and left-lingual-gyrus also showed decreases in BOLD response with learning. Concurrent with these decreases in BOLD response, an increasing connectivity between areas of the imaged network as well as the right-middle-frontal-gyrus with rising learning performance was revealed by a psychophysiological interaction (PPI) analysis. The increasing connectivity therefore occurs within an increasingly energy efficient network as learning proceeds. Strongest learning related connectivity between regions was found when analysing BA44 and l-IPL seeds. The results clearly show that BA44 and l-IPL is dynamically involved in linking gesture and sound and therefore provides evidence that one of the mechanisms required for the evolution of human communication is found within these motor regions.     

Observation of action: grasping with the mind's hand

Engagement of the primary motor cortex (MI) during the observation of actions has been debated for a long time. In the present study, we used the quantitative 14C-deoxyglucose method in monkeys that either grasped 3-D objects or observed the same movements executed by humans. We found that the forelimb regions of the MI and the primary somatosensory (SI) cortex were significantly activated in both cases. Our study resolves a debate in the literature, providing strong evidence for use of MI representations during the observation of actions. It demonstrates that the observation of an action is represented in the primary motor and somatosensory cortices as is its execution. It indicates that in terms of neural correlates, recognizing a motor behavior is like executing the same behavior, requiring the involvement of a distributed system encompassing not only the premotor but also the primary motor cortex. We suggest that movements and their proprioceptive components are stored as motor and somatosensory representations in motor and somatosensory cortices, respectively, and that these representations are recalled during observation of an action.     

Evidence for premotor cortex activity during dynamic visuospatial imagery from single-trial functional magnetic resonance imaging and event-related slow cortical potentials

A strong correspondence has been repeatedly observed between actually performed and mentally imagined object rotation. This suggests an overlap in the brain regions involved in these processes. Functional neuroimaging studies have consistently revealed parietal and occipital cortex activity during dynamic visuospatial imagery. However, results concerning the involvement of higher-order cortical motor areas have been less consistent. We investigated if and when premotor structures are active during processing of a three-dimensional cube comparison task that requires dynamic visuospatial imagery. In order to achieve a good temporal and spatial resolution, single-trial functional magnetic resonance imaging (fMRI) and scalp-recorded event-related slow cortical potentials (SCPs) were recorded from the same subjects in two separate measurement sessions. In order to reduce inter-subject variability in brain activity due to individual differences, only male subjects (n = 13) with high task-specific ability were investigated. Functional MRI revealed consistent bilateral activity in the occipital (Brodmann area BA18/19) and parietal cortex (BA7), in lateral and medial premotor areas (BA6), the dorsolateral prefrontal cortex (BA9), and the anterior insular cortex. The time-course of SCPs indicated that task-related activity in these areas commenced approximately 550-650 ms after stimulus presentation and persisted until task completion. These results provide strong and consistent evidence that the human premotor cortex is involved in dynamic visuospatial imagery.     

Long-term clinical follow-up after rotational atherectomy to coronary arterial stenosis in kawasaki disease

BACKGROUND: Although rotational atherectomy (RA) have been proven to be effective in calcified and non-dilatable lesions in Kawasaki disease, long-term efficacy and safety have not been established. METHOD: To evaluate long-term outcome, follow-up (FU) information was analyzed in 26 patients with Kawasaki disease, or 30 calcified and non-dilatable lesions with adjunctive balloon(BA) dilatation after RA from May 1993 to December 2002. Patient and lesion characteristics were: age 15 +/- 5 (8-28) years(yrs), and male-77%, previous myocardial infarction(MI)-4%, multi-vessel disease-35%, coronary aneurysm-87%. Lesion location was LAD-53%, RCA-40%, LCX-7%. Successful dilatation was achieved in 30 out of 30 lesions (100%) with adjunctive BA after RA. There were no in-hospital major events (Death/MI/coronary artery bypass surgery: CABG) and angiographic complications (perforation, no-reflow, spasm). RESULTS: Six-month FU quantitative coronary angiography(QCA) was performed in 23 patients or 27 lesions (90%). Binary restenosis (defined as > 50% diameter stenosis at FU) was detected in 4 of 27 lesions (15%). Target lesion(TL)-percutaneous coronary intervention(PCI) was performed in 3 of 27 lesions (11%). Neoaneurysm was occurred in 4 of 27 lesions (15%) which was associated with post % diameter stenosis (p = 0.002) and the crack of calcified arch detected by intravascular ultrasoud examination after adjunctive BA dilatation (p = 0.03). Anti-coagulant therapy was performed in all patients with neoaneurysm. Clinical FU data was achieved in all patients. Mean clinical FU interval was 6.1 +/- 3.4 yrs. Event-free survival rates at 5 yrs were as follows: Death 100%, Death/MI/CABG 100%, Death/MI/CABG/TL-PCI 86%, Death/MI/CABG/Any-PCI 86%. There was no any- PCI beyond 6 months. CONCLUSION: RA is an effective treatment in calcified and non-dilatable lesions with Kawasaki disease, associated with high procedural success rates. The safety and efficacy of RA appeared to be sustained at long-term FU.     

Self-paced movements induce high-frequency gamma oscillations in primary motor cortex

There has been increasing interest in the functional role of high-frequency (>30 Hz) cortical oscillations accompanying various sensorimotor and cognitive tasks in humans. Similar "high gamma" activity has been observed in the motor cortex, although the role of this activity in motor control is unknown. Using whole-head MEG recordings combined with advanced source localization methods, we identified high-frequency (65 to 80 Hz) gamma oscillations in the primary motor cortex during self-paced movements of the upper and lower limbs. Brief bursts of gamma activity were localized to the contralateral precentral gyrus (MI) during self-paced index finger abductions, elbow flexions and foot dorsiflexions. In comparison to lower frequency (10-30 Hz) sensorimotor rhythms that are bilaterally suppressed prior to and during movement (Jurkiewicz et al., 2006), high gamma activity increased only during movement, reaching maximal increase 100 to 250 ms following EMG onset, and was lateralized to contralateral MI, similar to findings from intracranial EEG studies. Peak frequency of gamma activity was significantly lower during foot dorsiflexion (67.4+/-5.2 Hz) than during finger abduction (75.3+/-4.4 Hz) and elbow flexion (73.9+/-3.7 Hz) although markedly similar for left and right movements of the same body part within subjects, suggesting activation of a common underlying network for gamma oscillations in the left and right motor cortex. These findings demonstrate that voluntary movements elicit high-frequency gamma oscillations in the primary motor cortex that are effector specific, and possibly reflect the activation of cortico-subcortical networks involved in the feedback control of discrete movements.     

完全性脊髓损伤亚急性期脑运动控制功能变化的功能磁共振研究

目的 探讨完全性脊髓损伤患者脑运动控制功能的变化情况。方法 2017年1月至2019年1月,病程3~6个月完全性脊髓损伤患者11例与健康人12例,在试图/实际运动、意象运动(MI)任务下行功能磁共振成像(fMRI)扫描,观察不同运动任务引发激活效应的空间分布和信号强度。结果 患者试图运动时的脑激活区域显著多于健康人实际运动时的激活区域,包括双侧初级感觉/运动皮质(S1/M1)、辅助运动区(SMA)、外侧苍白球(PA)、小脑、左侧丘脑和壳核等。健康人意象运动的比较,患者激活簇主要存在于右M1、SMA、背侧运动前区(PMd)、左SMA、岛叶和基底核。患者试图运动比意象运动在左M1、双SMA、扣带回运动区和右小脑诱发更多的兴奋。结论 亚急性期完全性脊髓损伤患者执行运动任务时,M1、SMA的兴奋模式基本正常,顶叶和小脑等感觉运动整合区域激活增加,提示发生适应性重组。     

Changes in the lipid composition of cell membranes in patients with bronchial asthma after glucocorticosteroid therapy

Levels of phospholipids (PL) and cholesterol (CS) were measured in erythrocytic membranes (EM) of 17 bronchial asthma (BA) patients. A relationship was established between BA aggravations and elevated CS but reduced PL concentrations in EM. These parameters responded positively on day 10 of glucocorticosteroids administration. There was a good clinical effect. The changes observed may be attributed to decreasing EM viscosity improving the function of adenylate cyclase and to the action of glucocorticosteroids on phospholipase A2 by rising PL values. Some patients, in the presence of abnormal PL and CS levels, showed qualitative shifts in PL: lower proportion of sphingomyelin-containing PL. Further study of specific membrane impairment in BA promises introduction of new approaches to BA treatment.     

运动想象对脊髓损伤患者大脑活动和脑网络重塑MR研究进展

运动想象（MI）及在此基础上的脑机接口已在脊髓损伤等运动功能障碍疾病的康复中取得良好效果，但其对运动功能康复的机制仍不十分明确。随着功能MR技术的发展，大脑激活和网络连接变化在MI中的作用被逐渐认识，为揭示MI康复机制及其临床应用提供了理论依据。     

The functional role of dorso-lateral premotor cortex during mental rotation: an event-related fMRI study separating cognitive processing steps using a novel task paradigm

Subjects deciding whether two objects presented at angular disparity are identical or mirror versions of each other usually show response times that linearly increase with the angle between objects. This phenomenon has been termed mental rotation. While there is widespread agreement that parietal cortex plays a dominant role in mental rotation, reports concerning the involvement of motor areas are less consistent. From a theoretical point of view, activation in motor areas suggests that mental rotation relies upon visuo-motor rather than visuo-spatial processing alone. However, the type of information that is processed by motor areas during mental rotation remains unclear. In this study we used event-related fMRI to assess whether activation in parietal and dorsolateral premotor areas (dPM) during mental rotation is distinctively related to processing spatial orientation information. Using a newly developed task paradigm we explicitly separated the processing steps (encoding, mental rotation proper and object matching) required by mental rotation tasks and additionally modulated the amount of spatial orientation information that had to be processed. Our results show that activation in dPM during mental rotation is not strongly modulated by the processing of spatial orientation information, and that activation in dPM areas is strongest during mental rotation proper. The latter finding suggests that dPM is involved in more generalized processes such as visuo-spatial attention and movement anticipation. We propose that solving mental rotation tasks is heavily dependent upon visuo-motor processes and evokes neural processing that may be considered as an implicit simulation of actual object rotation.     

Contribution of corticospinal tract damage to cortical motor reorganization after a single clinical attack of multiple sclerosis

The objectives of this study were to assess whether cortical motor reorganization in the early phase of multiple sclerosis (MS) is correlated with the clinical presentation and with specific damage to the corticospinal tract. Twenty patients with clinically isolated syndrome (CIS) and serial MR findings indicative of MS were selected. In 10 patients the CIS was hemiparesis (group H), and in 10 patients the CIS was optic neuritis (group ON). There were no significant differences in age, disease duration, total T2 lesion load (LL), and total T1 LL between group H and group ON. Ten age-matched healthy subjects served as controls (group C). All subjects were submitted to fMRI during a sequential finger-to-thumb opposition task of the right hand. Group H showed a significantly higher EDSS score and T1 LL calculated along the corticospinal tract than group ON. Three-group comparison by ANOVA showed significantly higher activation in group H than in the other two groups (P < 0.001). Significant foci were located in the sensory-motor cortex (BA 1-4), the parietal cortex (BA 40), the insula of the ipsilateral hemisphere, and the contralateral motor cortex (BA 4/6). Group ON showed, although at a lower level of significance (P < 0.01), higher activation of the contralateral motor-related areas than group C. Multiple regression analysis showed that T2 and T1 LL along the corticospinal tract and time since clinical onset positively correlated with activation in motor areas in both cerebral hemispheres (P < 0.005). Total T2 LL positively correlated with activation in motor areas in the contralateral hemisphere (P < 0.005). Total T1 LL and EDSS did not show any significant correlation. More severe specific damage to the motor pathway in patients with previous hemiparesis may explain the significantly higher involvement of ipsilateral motor areas observed in group H than in group ON. Furthermore, the significant correlation between the time since clinical onset and activation in motor areas suggests that cortical reorganization develops gradually in concomitance with the subclinical accumulation of tissue damage.