Deuschl G, Toro C, Valls-Solé J, Hallett M
Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
J Neurol Neurosurg Psychiatry. 1996 May;60(5):520-5. doi: 10.1136/jnnp.60.5.520.
Palatal tremor is divided into symptomatic palatal tremor (SPT) and essential palatal tremor (EPT) on the basis of clinical features. The inferior olive seems to be abnormal in SPT, but not EPT. Because the inferior olive is likely to be involved in several types of motor learning, it is hypothesised that motor learning would be abnormal in patients with SPT, but not those with EPT.
In six patients with SPT and four patients with EPT, two motor learning paradigms were studied--the classical conditioning of an acoustically elicited eyeblink with electrical supraorbital nerve shock and a test of adaptation of ballistic arm movements to a change of the gain.
Classical conditioning was impaired unilaterally or bilaterally in the patients with SPT, depending on whether they had unilateral or bilateral abnormalities of the inferior olives, except for the two least affected patients. All but one of the patients with EPT had normal conditioning. On the adaptation test of arm movements, most of the patients with SPT had impaired learning of the arm contralateral to the hypertrophied inferior olive, regardless of whether the abnormality was unilateral or bilateral, but all patients with EPT had normal results.
In SPT pseudohypertrophy of the inferior olive leads to defective cerebellar function, whereas in EPT the inferior olive functions normally.
根据临床特征，腭震颤分为症状性腭震颤（SPT）和原发性腭震颤（EPT）。在SPT中，下橄榄核似乎异常，但在EPT中并非如此。由于下橄榄核可能参与多种类型的运动学习，因此推测SPT患者的运动学习会异常，而EPT患者则不会。
对6例SPT患者和4例EPT患者，研究了两种运动学习范式——用眶上神经电刺激对听觉诱发眨眼进行经典条件反射，以及对弹道式手臂运动增益变化的适应性测试。
除了两名受影响最小的患者外，SPT患者的经典条件反射单侧或双侧受损，这取决于他们的下橄榄核是单侧还是双侧异常。除一名患者外，所有EPT患者的条件反射均正常。在手臂运动适应性测试中，大多数SPT患者与肥大的下橄榄核相对侧的手臂学习受损，无论异常是单侧还是双侧，但所有EPT患者的结果均正常。
在SPT中，下橄榄核的假性肥大导致小脑功能缺陷，而在EPT中，下橄榄核功能正常。
