Holloway V, Gadian D G, Vargha-Khadem F, Porter D A, Boyd S G, Connelly A
Radiology and Physics Unit, Cognitive Neuroscience Unit, Institute of Child Health, University College London, UK.
Brain. 2000 Dec;123 Pt 12:2432-44. doi: 10.1093/brain/123.12.2432.
Children who have suffered extensive unilateral brain injury early in life may show a remarkable degree of residual sensorimotor function. It is generally believed that this reflects the high capacity of the immature brain for cerebral reorganization. In this study, we investigated 17 patients who had undergone hemispherectomy for relief from seizures; eight of the patients had congenital brain damage and nine had sustained their initial insult at the age of 1 year or older. Sensorimotor functions of the hand were investigated using functional MRI (fMRI) during a passive movement task, somatosensory evoked potentials (SEPs) arising from electrical and vibration stimulation, and behavioural tests including grip strength, double simultaneous stimulation and joint position sense. On fMRI, two of the eight patients studied with this technique (one with congenital damage and one with damage acquired at the age of 3 years) showed activation in the sensorimotor cortex of the remaining hemisphere with passive movement of the hemiplegic hand. The location of the ipsilateral brain activation was similar to that found on movement of the normal contralateral hand, although the latter was greater in spatial extent. In one of these patients, a greater role was demonstrated for the ipsilateral secondary sensorimotor area (compared with the ipsilateral primary sensorimotor area) for movement of the hemiplegic hand than for movement of the normal hand. Median nerve stimulation of the hemiplegic hand showed reproducible early-latency ipsilateral SEP components in the remaining sensorimotor cortex in 10 of the 17 patients (five with congenital and five with acquired disease). Five of the patients who demonstrated ipsilateral electrical SEPs also showed ipsilateral vibration SEPs (two with congenital and three with acquired disease). The behavioural tests revealed residual sensorimotor function in 14 of the patients; however, not all of the patients who exhibited ipsilateral SEP or fMRI responses had residual sensorimotor function in the hemiplegic hand. Ipsilateral sensorimotor responses were demonstrated both in patients with congenital disease and those with acquired disease, suggesting that factors additional to aetiology and age at injury may influence the degree of residual sensorimotor function and cerebral reorganization.
早年遭受广泛单侧脑损伤的儿童可能会表现出显著程度的残余感觉运动功能。人们普遍认为，这反映了未成熟大脑进行脑重组的高能力。在本研究中，我们调查了17例因癫痫发作而接受半球切除术的患者；其中8例患者有先天性脑损伤，9例在1岁或更大年龄时遭受了最初的损伤。在被动运动任务期间，使用功能磁共振成像（fMRI）、电刺激和振动刺激产生的体感诱发电位（SEP）以及包括握力、双侧同时刺激和关节位置觉在内的行为测试，对手部的感觉运动功能进行了研究。在fMRI上，使用该技术研究的8例患者中有2例（1例先天性损伤，1例3岁时获得性损伤）在偏瘫手被动运动时，剩余半球的感觉运动皮层出现激活。同侧脑激活的位置与正常对侧手运动时发现的位置相似，尽管后者在空间范围上更大。在其中1例患者中，与正常手运动相比，偏瘫手运动时同侧二级感觉运动区（与同侧初级感觉运动区相比）发挥了更大作用。对偏瘫手进行正中神经刺激时，17例患者中有10例（5例先天性疾病，5例获得性疾病）在剩余感觉运动皮层中显示出可重复的早期潜伏期同侧SEP成分。5例显示同侧电SEP的患者也显示出同侧振动SEP（2例先天性疾病，3例获得性疾病）。行为测试显示14例患者有残余感觉运动功能；然而，并非所有表现出同侧SEP或fMRI反应的患者在偏瘫手中都有残余感觉运动功能。先天性疾病患者和获得性疾病患者均表现出同侧感觉运动反应，这表明除病因和受伤年龄外，其他因素可能会影响残余感觉运动功能和脑重组的程度。
