Dynamic heart rate changes have often been described in electroconvulsive therapy (ECT). However, the specific timing of these changes has not been reported. To examine the cardiac autonomic nervous changed by ECT, we evaluated heart rate and spectral analysis of heart rate variability (HRV) during ECT. Four patients with depression and four patients with schizophrenia who all underwent ECT were included. All ECT sessions were assessed using electrocardiograms (ECG). Heart rate was recorded and analyzed for the HRV indices, HF (an index of parasympathetic activity) and LF/HF (an index of sympathetic activity) during 4 minutes before and after seizure onset. Averaged heart rates over three heart beats pre-seizure and post-seizure onset were compared. Averages of HRV power in the range of 30–100 and 100–170 seconds following a seizure were assessed. Patients showed a significant prolongation of the average over three heart rates just after a seizure, suggesting parasympathetic dominance at this first phase. The average power of LF/HF significantly increased in the latency of 30–100 seconds after a seizure, while the average power of HF significantly increased in the window of 100–170 seconds after a seizure, reflecting sympathetic activation in the second phase and parasympathetic activation in the third phase. The evaluation of heart rates and HRV revealed a triphasic change from parasympathetic to sympathetic to parasympathetic cardiac autonomic activity following a seizure.

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We examined movement related cerebral fields by using the cross-correlogram method to compare the accelerometer and surface electromyography (EMG). The EMG was attached on the thenar muscles of the right hand and the accelerometer was attached on the right thumb between the interphalangeal joint and the metatarsophalangeal joint. Repeated self-paced movements of alternating the thumb flexion and extension for 90 seconds were recorded in magnetoencephalography (MEG). Cross-correlogram of MEG-accelerometer and MEG-EMG were analyzed to determine the signal source, by using the Equivalent current dipole (ECD) method and the Minimum Norm Estimates (MNE) method. We obtained the clear cross-correlogram of MEG-accelerometer and MEG-EMG. The results of the measurement with the accelerometer and the EMG were approximately equal on ECD and MNE. In this study, we concluded that the movement related cerebral fields obtained from the cross-correlogram method using the accelerometer was useful.

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Triple stimulation technique (TST) is a new collision technique that combines transcranial magnetic stimulation (TMS) of motor cortex and electrical stimulation of peripheral nerve. It is considered to be more sensitive than the conventional motor evoked potential (MEP) in detecting pyramidal tract dysfunction because it can reduce the effect of temporal dispersion in the pyramidal tract. This study aimed to test the utility of TST in the evaluation of pyramidal tract dysfunction. Eleven patients (aged 28–81 years) were included (amyotrophic lateral sclerosis N=3, spastic paraplegia N=3, multiple sclerosis N=1, cervical spondylosis N=3, psychogenic paralysis N=1). Patients were examined clinically, with conventional (single-pulse) TMS and with TST. MEPs were recorded from abductor digiti minimi muscle. Conventional TMS parameters included resting motor threshold (RMT), MEP amplitude, central motor conduction time (CMCT) and cortical silent period (CSP). Of 6 patients who exhibited clinical pyramidal signs (spastic muscle tone or hyperreflexia), TST parameter was abnormal in 3 patients (50%), and RMT in 1 patient (17%) while MEP amplitude and CMCT were all normal. Of 4 patients who did not exhibit clinical pyramidal sign, TST was abnormal in 3 patients (75%), CMCT in 3 patients (75%), RMT in 1 patient (25%), and MEP amplitude in 1 patient (25%). RMT was abnormal in one patient with psychogenic paralysis, however, TST, MEP amplitude and CMCT of the patient were all normal. In ALS, 2 of 3 patients (67%) showed abnormal TST, 1 of 3 showed abnormal RMT (33%), and 2 of 2 showed abnormal CSP (100%), but MEP amplitude and CMCT were normal in these 3 patients. These results suggest that TST is a useful technique when evaluating pyramidal tract dysfunction.

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