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Functional neurological disorders differ from malingering/factitious disorders and are diagnosed based solely on careful history taking and neurological evaluation. Some clinical characteristics, including distractibility, entrainability, and variability are important to identify the positive physical signs that indicate functional alterations. Thorough investigations are not essential to exclude organic pathologies, whereas electrophysiological and radiological findings are sometimes useful. Neurologists play an important role when they explain the diagnosis to the patient. The explanation itself may be therapeutic, when delivered successfully and may help patients to understand the nature and mechanisms underlying their movement disorder. A multidisciplinary team approach, including coordination between rehabilitation therapists and psychotherapists may produce positive treatment outcomes, particularly in movement disorder centers. In this article, we discuss some functional neurological disorders, including those in patients with functional movement disorders (involuntary movements) together with video presentations.

Some diseases that are associated with dopamine deficiency are accompanied by psychiatric symptoms, including Parkinson’s disease. However, the mechanism by which this occurs has not been clarified. Previous studies found that dopamine-deficient (DD) mice exhibited hyperactivity in a novel environment. This hyperactivity is improved by clozapine and donepezil, which are used to treat psychiatric symptoms associated with dopamine deficiency (PSDD). We considered that DD mice could be used to study PSDD. In the present study, we sought to identify the pharmacological mechanism of PSDD. We conducted locomotor activity tests by administering quetiapine and drugs that have specific actions on serotonin (5-hydroxytryptamine [5-HT]) receptors and muscarinic receptors. Changes in neuronal activity that were induced by drug administration in DD mice were evaluated by examining Fos immunoreactivity. Quetiapine suppressed hyperactivity in DD mice while the 5-HT1A receptor antagonist WAY100635 inhibited this effect. The number of Fos-positive neurons in the median raphe nucleus increased in DD mice that exhibited hyperactivity and was decreased by treatment with quetiapine and 5-HT1A receptor agonists. In conclusion, hyperactivity in DD mice was ameliorated by quetiapine, likely through 5-HT1A receptor activation. These findings suggest that 5-HT1A receptors may play a role in PSDD, and 5-HT1A receptor-targeting drugs may help improve PSDD.

This study aimed to evaluate genotype-phenotype correlations of Parkinson’s disease (PD) patients with phospholipase A2 group V (PLA2G6) variants. We analyzed the DNA of 798 patients with PD, including 78 PD patients reported previously, and 336 in-house controls. We screened the exons and exon-intron boundaries of PLA2G6 using the Ion Torrent system and Sanger method. We identified 21 patients with 18 rare variants, such that 1, 9, and 11 patients were homozygous, heterozygous, and compound heterozygous, respectively, with respect to PLA2G6 variants. The allele frequency was approximately equal between patients with familial PD and those with sporadic PD. The PLA2G6 variants detected frequently were identified in the early-onset sporadic PD group. Patients who were homozygous for a variant showed more severe symptoms than those who were heterozygous for the variant. The most common variant was p.R635Q in our cohort, which was considered a risk variant for PD. Thus, the variants of PLA2G6 may play a role in familial PD and early-onset sporadic PD.

Background The role of B cells in the pathogenesis of multiple sclerosis (MS) is a subject of much research. We report a case of a MS patient who presented with subacute diffuse lesions in the limbic system and short-term memory loss. Case presentation A male patient had experienced numbness in the left upper extremity at the age of 17 years, but this disappeared without treatment. At 19 years-of-age, he developed subacute short-term memory loss followed by paralysis and sensory disturbance in the left upper and lower extremities. Magnetic resonance brain fluid-attenuated/T2-weighted imaging showed diffuse high-intensity lesions in the medial parts of both temporal lobes, and spotty multiple lesions in the periventricular and subcortical white matter. Twenty days later, a new lesion was observed around the right putamen, and the temporal lesions had disappeared. A symptomatic cervical lesion with gadolinium enhancement was observed at C3. This lesion involved just one vertebral segment. Cerebrospinal fluid analysis showed no pleocytosis or elevated protein levels, but did show oligoclonal immunoglobulin G bands. No antibodies against aquaporin-4 or myelin oligodendrocyte glycoprotein were detected in the serum, and anti-N-methyl-D-aspartate receptor was not detected in the cerebrospinal fluid. We diagnosed the patient with MS despite the atypical diffuse lesions in the limbic system and the short-term memory loss. Corticosteroid medication effectively treated the symptoms in his extremities and his impaired memory. Conclusions The present case shows that cortical lesions can occur in MS patients and might be induced by B cell-mediated mechanisms.

Despite the recent advent of neuro-radiographic techniques, creating a ‘perfect’ human brain atlas providing precise and consistent images with minimal distortion is practically difficult. In this study, we created a new human brain atlas from cadaveric brains with serial sections of 50 μm thickness covering the entire basal ganglia. Human cerebral hemispheres were obtained from 10 donated cadavers and fixed in 10% formalin solution, cut in a block measuring 50 mm × 30 mm × 50 mm around the midpoint of the anterior and posterior commissures and frozen at −40 °C. Each block was cut into 50-μm-thick sections on the freezing microtome and the cross-sectioned surface was photographed. Simultaneously, every 10th slice from one sagittal hemisphere was sampled and stained using the Kluver-Barrera method. Prepared slides were photographed under light microscopy, and data from digital images of the cross-sectioned surface (DICSS) and digital images from microscopic sections (DIMS) were processed. Gray areas on DICSS largely represented areas of dense cellularity, and around subthalamic nucleus (STN), the zona incerta and field of Forel were clearly distinguishable on the anterosuperior side, as was the substantia nigra on the caudal side. DICSS successfully delineated the anatomical structure identical to the STN and surrounding contiguous nuclei. This new brain atlas will allow elucidation of anatomy that cannot be clearly disclosed from modern radiographic imaging or is very difficult to analyze with spatially inconsistent histological sections, and will contribute to further progress in anatomical studies of the human basal ganglia.

Objective It has been suggested that abnormal synchronization and oscillation of neuronal activity in the subthalamic nucleus (STN) is associated with sensorimotor dysfunction in Parkinson's disease (PD). We investigated the bilateral subcortico-cortical functional coupling in PD patients. Methods We simultaneously recorded local field potentials from the bilateral STN using electrodes inserted for deep brain stimulation and electroencephalograms from the bilateral motor cortices (MCx) in 11 patients at rest, and analyzed their coherences and causalities. Results Significant coherence in the sub-beta and beta frequency bands was simultaneously observed between the STN and contralateral STN (STN–cSTN), the STN and ipsilateral MCx (STN–iMCx), and the STN and contralateral MCx (STN–cMCx). In each patient, the frequency of the peak STN–cSTN coherence was similar to that of the peak STN–iMCx and STN–cMCx coherence. The causality between the STN and MCx was strongest in the one-way direction from the MCx to the ipsilateral STN. Conclusions Abnormal oscillations in the STN in the sub-beta and beta bands were functionally coupled among bilateral STN and MCx at the eigen-frequency in individual patients with PD. Significance Synchronized activity through cortico-subcortical transmission may have an important role in the pathophysiology of PD.

We describe the case of a 42-year-old Japanese woman with childhood-onset myoclonus, dystonia, and psychiatric symptoms, including anxiety, phobia, and exaggerated startle response. The diagnosis was confirmed as myoclonus-dystonia (DYT11) by identifying a mutation in the gene encodingε-sarcoglycan. Interestingly, while motor-related symptoms in DYT11 generally improve with alcohol ingestion, the patient’s symptoms were exacerbated by alcohol intake. Her severe and medically intractable symptoms were alleviated by bilateral deep brain stimulation of the globus pallidus internus, with myoclonus and dystonia scores showing 70% improvement after the surgery compared to presurgical scores. This is the first report of a genetically confirmed case of DYT11 in Japan. This paper together with other recent reports collectively demonstrates that DYT11 patients are distributed worldwide, including Asia. Thus, a diagnosis of DYT11 should be considered when clinicians encounter a patient with childhood-onset myoclonus and/or dystonia with psychiatric symptoms, regardless of ethnic background.

A 64-year-old woman with Parkinson is disease had a severe resting tremor that was not completely relieved by right-sided gamma knife thalamotomy (GKT). We performed bilateral staged thalamic deep brain stimulation (DBS) and compared the right and left ventral intermediate nucleus (Vim) of the thalamus including the frequency of single units recorded with microelectrodes, and also the somatotopical distribution of kinaesthetic cells (Ki). The average frequency of units for the presumed left Vim exceeded that of the right (22.6 +/- 19.2 Hz vs. 14.3 +/- 8.8 Hz). Regarding the somatotopic distribution of Ki, the receptive field for the leg, which is usually situated in the dorsolateral Vim, was more widely scattered in the right Vim than the non-lesioned left side. Our findings raise the possibility that the specific properties of the neurons changed due to partial coagulation by GKT within both the coagulated and the surrounding thalamic lesions.

The volitional control of muscle contraction and relaxation is a fundamental component of human motor activity, but how the processing of the subcortical networks, including the subthalamic nucleus (STN), is involved in voluntary muscle contraction (VMC) and voluntary muscle relaxation (VMR) remains unclear. In this study, local field potentials (LFPs) of bilateral STNs were recorded in patients with Parkinson’s disease (PD) while performing externally paced VMC and VMR tasks of the unilateral wrist extensor muscle. The VMC- or VMR-related oscillatory activities and their functional couplings were investigated over the theta (4–7 Hz), alpha (8–13 Hz), beta (14–35 Hz), and gamma (40–100 Hz) frequency bands. Alpha and beta desynchronizations were observed in bilateral STNs at the onset of both VMC and VMR tasks. On the other hand, theta and gamma synchronizations were prominent in bilateral STNs specifically at the onset of the VMC task. In particular, just after VMC, theta functional coupling between the bilateral STNs increased, and the theta phase became coupled to the gamma amplitude within the contralateral STN in a phase-amplitude cross-frequency coupled manner. On the other hand, the prominent beta-gamma cross-frequency couplings observed in the bilateral STNs at rest were reduced by the VMC and VMR tasks. These results suggest that STNs are bilaterally involved in the different performances of muscle contraction and relaxation through the theta-gamma and beta-gamma networks between bilateral STNs in patients with PD.

In order to clarify the clinical and genetic features of SCA6, we retrospectively analyzed 140 patients. We observed an inverse correlation between the age of onset and the length of the expanded allele, and also between the age of onset and the sum of CAG repeats in the normal and the expanded alleles. The ages of onset of four homozygous patients correlated better with the sum of CAG repeats in both alleles rather than with the expanded allele calculated from heterozygous SCA6 subjects. Clinically, unsteadiness of gait was the main initial symptom, followed by vertigo and oscillopsia, and cerebellar signs were detected in nearly 100% of the patients. In contrast, extracerebellar signs were relatively mild and infrequent. The results of neuro-otological examination performed in 22 patients suggested the purely cerebellar abnormalities of ocular movements in nature. There was a close relationship between downbeat positioning nystagmus (DPN) and positioning vertigo, which became more common in the later stage. We conclude that total number of CAG repeat-units in both alleles is a good parameter for assessment of age of onset in SCA6 including homozygous patients. In addition, clinical and neuro-otological examinations suggested that SCA6 is a disease with predominantly cerebellar dysfunction.

We report the autopsy case of a 74-year-old woman. Onset of gait disturbance and left-side dominant bilateral motor disturbance in the patient led to bilateral progressive apraxia. This was associated with a decline in motor imagery, right-side dominant atrophy of the central sulcus region, and a decrease in cerebral blood flow during illness. She died of respiratory failure that had progressively worsened over a 9-year period. Pathologically, she exhibited right-side dominant cerebral atrophy; neuronal loss, gliosis, and astrocytic plaques were mainly present in the frontal lobe. She was subsequently diagnosed with corticobasal degeneration (CBD). The premotor and primary motor areas revealed marked degeneration; in addition, severe myelin pallor was observed in these regions, and it was suggested that such pathological features were responsible for the apraxia. We believe the present case is valuable since very few reports have provided a detailed description of clinicopathological apraxia in association with CBD.

Objectives: The basal ganglia (BG) play an important role in controlling saccades. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is widely used as a treatment of Parkinson disease (PD) by altering the function of the BG. Nevertheless, the effects of STN DBS on saccade performance are not fully clarified in a systematic manner. In this study, we examined the effects of bilateral STN DBS on both the initiation and inhibition of saccades in PD. Methods: Thirty-two patients with PD performed 4 oculomotor tasks. Two tasks (visually guided saccades and gap saccades) were reflexive and 2 (memory-guided saccades [MGS] and antisaccades) were volitional. While taking their regular doses of antiparkinsonian drugs, patients performed these tasks under 2 conditions: during DBS (DBS-on condition) and without DBS (DBS-off condition). Fifty-one age-matched subjects served as controls. Results: In the DBS-on condition, parameters of saccade initiation were improved in all tasks, with shorter latencies and increased amplitudes, except for MGS latency. STN DBS improved the ability to suppress unwanted saccades to the cue stimulus in the MGS task. However, it did not suppress prosaccades during the antisaccade task. Conclusions: These results suggest that deep brain stimulation (DBS) of the subthalamic nucleus (STN) affects the neural pathway common to both reflexive and volitional saccades, possibly by acting on the STN–substantia nigra pars reticulata–superior colliculi pathway. STN DBS may set the functional level of the superior colliculi appropriate for both saccade initiation and inhibition through this pathway. These findings provide novel insights into the pathophysiology of Parkinson disease and may yield better treatment strategies.

Involuntary movements are of numerous types. It is difficult to treat involuntary movements by medication, and the mechanisms underlying involuntary movements are unclear. Stereotactic surgery has been effective for the treatment of involuntary movements. Outcomes of surgical treatments are excellent indicators for understanding the clinical differentiation or pathophysiological mechanism of involuntary movements. The clinical observations of involuntary movements following stereotactic surgery are described in this chapter.

Bilateral symptoms and signs of Parkinson's disease (PD) are often improved by unilateral subthalamic nucleus deep brain stimulation (STN-DBS). However, the mechanism for such bilateral effects is unknown. This study was intended to examine effects of unilateral STN-DBS using positron emission computed tomography (PET) and to elucidate mechanisms for bilateral improvement achieved by unilateral stimulation.We conducted (18)F-fluorodeoxyglucose ((18)FDG) and (18)F-fluorodopa ((18)F-DOPA ) PET scans in PD patients whose bilateral limb symptoms and axial symptoms were improved by unilateral DBS. Two scans were performed in each PET study: when DBS was on and off. We compared those images using statistic parametric mapping (SPM) 99.The significant clinical improvement obtained by unilateral DBS was shown as improvements in bilateral motor limb, axial, and gait subscores of the Unified PD Rating Scale (UPDRS). Moreover, (18)FDG PET revealed significant metabolic increases in the ipsilateral ventrolateral thalamic areas and metabolic decrease at the contralateral globus pallidus interna (GPi). In contrast, (18)F-DOPA PET showed no significant differences between DBS on and off.Ipsilateral thalamic activation might induce ipsilateral motor cortical activation, which explains the improvement of contralateral limb symptoms. Furthermore, deactivation of the contralateral GPi might disinhibit the thalamus and contralateral motor cortex, which explains reduction of ipsilateral limb symptoms. These results suggest the mechanisms for bilateral improvement achieved by unilateral DBS.

Our clinical observations by surface electromyography show that the effects of Vim DBS and STN DBS on tremor are different. It might be postulated that Vim DBS inhibits the current rising tremor, whereas STN DBS modulates the tremor circuit. This investigation is preliminary and it is as yet very difficult to speculate the mechanisms underlying the modulation of the tremor circuit and the mechanisms of Vim and STN. Further clinical investigations should be carried out.

According to evidenced-based criteria, surgical treatment with subthalamic stimulation is indicated for advanced Parkinson's disease with severe motor complications. Currently, the treatment is indicated for patients in whom medical treatment has failed even if the patient is still in an early stage. This study investigated the efficacy and safety of unilateral subthalamic stimulation for patients with early-stage Parkinson's disease. We evaluated the Unified Parkinson's Disease Rating Scale (UPDRS) and the Schwab England ADL score before and 6 months after this treatment in 6 patients with early-stage Parkinson's disease demonstrating predominantly unilateral parkinsonian symptoms. We implanted a stimulation electrode (model 3387 or 3389) unilaterally on the side showing dominate symptoms, using both MRI and electrophysiological guidance. Six months after the beginning of stimulation, the UPDRS motor score without medication was improved by 64% and the Schwab England ADL score was improved by 23%. There were no adverse events except for asymptomatic intra-ventricular hemorrhage in one patient. Unilateral subthalamic stimulation is a useful treatment for patients with early-stage Parkinson's disease showing predominantly unilateral parkinsonian symptoms. However, long-term results of subthalamic stimulation for early-stage patients remain unclear.

Chronic stimulation of subthalamus nucleus (STN) is effective in treating severe motor fluctuation and levodopa induced dyskinesia as well as parkinsonian motor symptoms. The improvement of peak-dose/diphasic dyskinesias of STN stimulation is considered to be due to the decrease in the daily dosage of antiparkinsonian drugs. However one report pointed out that STN stimulation improved directly levodopa induced dyskinesia. Moreover the timing of the improvement for levodopa induced dyskinesia is not yet obvious. In the present study, we have assessed variance in the latency of improvement of levodopa induced dyskinesia due to STN stimulation. In addition, we would clarify an issue which cite of STN stimulation improved parkinsonian symptoms and motor complication (motor dyskinesias and motor fluctuation). We have studied seven patients diagnosed with advanced idiopathic Parkinson's disease with motor fluctuations and levodopa induced dyskinesias. Before and after the implantation of stimulating electrode, patients were assessed by the Unified Parkinson's Disease Rating Scale and % 'OFF' motor state. The dosage of the antiparkinsonian medication was not modified for one month prior to implantation. Following implantation, dosage of the medication and strength of stimulation was adjusted, if necessary. Symptoms of motor fluctuation and dyskinesia improved in all patients six month after surgery. The mean off-time duration and dyskinesia disability improved compared with presurgical conditions. However, the time course of the improvement of dyskinesias was not the same among patients. Contralateral limb dyskinesias in three patients improved immediately after the stimulation without modification of medication. In contrast, the stimulation worsened contralateral limb dyskinesias in other three patients immediately following the surgery. In two of the three patients, dyskinesias gradually improved within one month after surgery without reducing the dosage of medication. Dyskinesias of the other patient improved following a reduction in the dosage of medication one month after the surgery. Improvement of parkinsonian symptoms of the patients with longer latency of stimulation effect for dyskinesias was better than that of the patients with shorter latency. Stimulation cite of the former group appeared to locate more central than that of the latter group. Latency and strength of the effects of STN stimulation are variable.

An antisaccadic paradigm in which saccades are directed towards the mirror location opposite to that of target appearance has been thought to reflect frontal lobe function and a saccade-inhibitory mechanism. In order to clarify now the cortical mechanism differs between antisaccades (AS) and reflexive visually guided saccades (VS), we measured scalp EEG potentials preceding AS and VS in 9 young normal subjects, as well as the magnetic brain activities during AS and VS in 1 of them. Prior to the right and left saccades in both paradigms, our measurements revealed the appearance of a slowly developing negative potential, the presaccadic negativity (PSN), and then a steeper negative potential, the presaccadic steep negativity (PSSN). The onset of PSSN was significantly earlier and the maximum amplitude of PSSN was significantly greater in AS than in VS. The peak amplitude of PSSN at each middle electrode (Fz, Cz, Pz) was generally greater in AS than in VS in both directions of saccades. In one normal subject, the difference between AS and VS in the magnetic field distribution just prior to saccades in both directions was demonstrated as current dipoles on the bilateral frontal areas. Our results suggest that the activation of the bilateral frontal lobes is greater prior to AS than it is prior to VS.

The relationships between lesion location and clinical outcome following posteroventral pallidotomy for Parkinson's disease were studied. Forty-four patients were operated forty-six times and studied with neurological and psychological examinations before and after pallidotomy. Lesion location was confirmed using films with a coagulation electrode which were X-rayed during the operation. Changes of intelligence were observed in the patients with anteromedial lesions. Wearing-off phenomenon in four patients and dopa-induced dyskinesia in three patients were not improved following pallidotomy in twenty patients with severe wearing-off and dyskinesia. Lesions in the patients with no improvement of wearing off were located more lateral and those in the patients with sustained severe dyskinesia were located more dorsal in the internal part of the globus pallidus. It may be concluded that clinical outcome is related to lesion location.

Background: Unilateral spatial neglect has been rarely reported in patients with AD, although they often have right and left asymmetry of temporoparietal dysfunction. Objective: To investigate if patients with AD would show unilateral spatial neglect in the line bisection test, and to reveal the relationship between their neglect and the area of cerebral dysfunction. Method:— Thirty-two patients with mild to moderate AD and 32 age-matched healthy control subjects underwent an extensive line bisection test. SPECT was also obtained for the patients. Results: Rightward bisection errors exceeded the normal range in 25% of patients with AD. They exhibited greater rightward errors for the longer lines in the left hemispace than in the right hemispace, and with the right hand than with the left hand; this corresponds to the characteristics of neglect seen after right hemisphere lesions. All patients who bisected 200 mm lines with errors over 10 mm showed disproportionate lowering of performance IQ and asymmetric right hemisphere hypoperfusion, especially in the temporoparietal region. Seventy-five percent of the patients performed normally in the center presentation but erred slightly toward the body midline in the right and left hemispaces. Conclusion: Left unilateral spatial neglect in mild to moderate AD may be rather common if tested with the line bisection test. Rightward errors over 10 mm suggest right temporoparietal dysfunction. In AD, three or more bisections of 200 mm lines in the center presentation are recommended for detection of neglect. Patients with AD but without neglect may have difficulty in shifting attention into the peripheral sector of the egocentric space.

Optokinetic response and adaptation of the VOR were investigated in a patient with chronic cortical blindness. Our results suggest that: 1) optokinetic response was present in a patient with cortical blindness. This optokinetic response may relate to the extrastriate pathways: 2) the occurrence of VOR adaptation was shown in a patient with cortical blindness, which may indicate preservation of the pathways of the visual-vestibular interaction in the brain stem and cerebellum. The result is in agreement with previous reports in experimental animals; 3) less adaptation of the VOR in this patient than in normal adults may relate to a chronic loss of visual feed back. To the best of our knowledge, this is the first report of adaptation of the VOR in a patient with cortical blindness.

We studied a family in which three siblings had an identical clinical feature indistinguishable from familial amyotrophic lateral sclerosis (ALS), consisting of progressive generalized neurogenic muscular atrophy with hyporeflexia and normal sensations beginning in the fourth decade. The duration of illness was about 4 years in all affected members. Autopsy of one patient revealed multiple foci of spongy degeneration in the white matter of the spinal cord, brain stem, cerebellum, and the thalamus, characterized by vacuoles of various size, foamy macrophages and degenerating swollen axons. These changes were most marked in the spinal cord, where there was neither pyramidal tract involvement nor neuronal loss in the anterior horn. The pathological findings were different from those of ALS. A similar disease affected the siblings' mother, suggesting an autosomal dominant inheritance. The disease in the kindred, therefore, appears to be a unique hereditary disorder.

Patients with typical left unilateral spatial neglect bisected lines after cueing to the left end-point, the fixation point being monitored with an eye camera. They persisted with the point of initial fixation made after cueing and placed the mark there without searching leftwards again. The rightward shift of fixation to the initial point of fixation thus determined the location of the subjective midpoint. We consider that rightward attentional bias increased the amplitude of this shift that was planned on the basis of the perception of the whole line while cueing. This hypothesis may explain smaller but obvious rightward bisection errors found in the cueing condition.

We describe acute mononeuropathy multiplex in a patient with chronic ulcerative colitis. The symptoms of neuropathy were well correlated with the disease activity of colitis. Both electrophysiological study and sural nerve biopsy revealed axonal degeneration. Mononeuropathy multiplex may be an extraintestinal manifestation of ulcerative colitis.

In 28 patients with definite multiple sclerosis (MS) and 21 patients with a functionally complete transection of the spinal cord sympathetic skin responses (SSR) from both the palms and soles were studied. In the patients with a complete transection at T3 or 4, SSRs were impaired in the palms as well as the soles, and most patients with a transection at T11 or T12 had normal SSRs in the soles. These findings indicate that the central pathway mediating the SSR descends to the upper thoracic cord where connections are made with the sympathetic distribution to the palms, and then to the lower thoracic cord to reach the sympathetic outflow to the soles. This is compatible with the anatomical knowledge of the sympathetic system. Of the MS patients, 75% had abnormal SSR results. The SSR for the soles was more sensitive than that for the palms. The incidence of SSR abnormality was as high as those of somatosensory evoked potential (SEP) (79%) and visual evoked potential (VEP) (75%) abnormalities. Of the patients with normal SEPs 14% had impaired SSRs and 21 % had abnormal SSR with normal VEPs. When the results of these 3 tests were combined, the abnormality increased to 100%. From our study, the SSR probably reflects not only postganglionic sympathetic activity but also preganglionic function. The SSR is therefore useful in evaluating myelopathy, providing information different from that given by assessment of the somatic nervous system. Since the SSR detected a few MS lesions which were not demonstrated by other evoked potentials, it is potentially a new tool for the detection of MS lesions in addition to conventional evoked potential studies.