Intrinsic Auricular Muscle Zone Stimulation Improves Walking Parameters of Parkinson's Patients Faster Than Levodopa in the Motion Capture Analysis: A Pilot Study.

It has been demonstrated that intrinsic auricular muscles zone stimulation (IAMZS) can improve the motor symptoms of Parkinson's disease (PD) patients who are examined with the Unified Parkinson's Disease Rating Scale (UPDRS) motor scores. In the present pilot study, using motion capture technology, we aimed to investigate the efficacy of IAMZS compared to medication alone or in combination with medication. Ten PD patients (mean age: 54.8 ± 10.1 years) were enrolled. Each participant participated in three different sessions: sole medication, sole stimulation-20 min of IAMZS, and combined IAMZS (20 min) and medication. Each session was performed on different days but at the same time to be aligned with patients' drug intake. Motion capture recording sessions took place at baseline, 20, 40, and 60 min. Statistical analysis was conducted using one-way repeated measures ANOVA. Bonferroni correction was implemented for pairwise comparisons. The sole medication was ineffective to improve gait-related parameters of stride length, stride velocity, stance, swing, and turning speed. In the sole-stimulation group, pace-related gait parameters were significantly increased at 20 and 40 min. These improvements were observed in stride length at 20 (p = 0.0498) and 40 (p = 0.03) min, and also in the normalized stride velocity at 40 min (p-value = 0.02). Stride velocity also tended to be significant at 20 min (p = 0.06) in the sole-stimulation group. Combined IAMZS and medication demonstrated significant improvements in all the time segments for pace-related gait parameters [stride length: 20 min (p = 0.04), 40 min (p = 0.01), and 60 min (p < 0.01); stride velocity: 20 min (p < 0.01), 40 min (p = 0.01), and 60 min (p < 0.01)]. These findings demonstrated the fast action of the IAMZS on PD motor symptoms. Moreover, following the termination of IAMZS, a prolonged improvement in symptoms was observed at 40 min. The combined use of IAMZS with medication showed the most profound improvements. The IAMZS may be particularly useful during medication off periods and may also postpone the long-term side effects of high-dose levodopa. A large scale multicentric trial is required to validate the results obtained from this pilot study. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03907007.

Electrophysiological Investigations in Orthostatic Myoclonus: Preliminary Findings.

We report the clinical and electrophysiological findings in seven patients with orthostatic myoclonus (OM) associated with gait initiation failure and falls. OM is one of the causes of unsteadiness of stance and gait, and it may develop as a symptom of neurodegenerative disorders. Both positive myoclonic bursts and negative myoclonus may be seen in electrophysiological recordings, and electrophysiological analysis suggests a subcortical origin for OM.

Rapid Alleviation of Parkinson's Disease Symptoms via Electrostimulation of Intrinsic Auricular Muscle Zones.

Background: Deep brain stimulation of the subthalamic nucleus (STN-DBS) and the pedunculopontine nucleus (PPN) significantly improve cardinal motor symptoms and postural instability and gait difficulty, respectively, in Parkinson's disease (PD). Objective and Hypothesis: Intrinsic auricular muscle zones (IAMZs) allow the potential to simultaneously stimulate the C2 spinal nerve, the trigeminal nerve, the facial nerve, and sympathetic and parasympathetic nerves in addition to providing muscle feedback and control areas including the STN, the PPN and mesencephalic locomotor regions. Our aim was to observe the clinical responses to IAMZ stimulation in PD patients. Method: Unilateral stimulation of an IAMZ, which includes muscle fibers for proprioception, the facial nerve, and C2, trigeminal and autonomic nerve fibers, at 130 Hz was performed in a placebo- and sham-controlled, double-blinded, within design, two-armed study of 24 PD patients. Results: The results of the first arm (10 patients) of the present study demonstrated a substantial improvement in Unified Parkinson's Disease Ratings Scale (UPDRS) motor scores due to 10 min of IAMZ electrostimulation (p = 0.0003, power: 0.99) compared to the placebo control (p = 0.130). A moderate to large clinical difference in the improvement in UPDRS motor scores was observed in the IAMZ electrostimulation group. The results of the second arm (14 patients) demonstrated significant improvements with dry needling (p = 0.011) and electrostimulation of the IAMZ (p < 0.001) but not with sham electrostimulation (p = 0.748). In addition, there was a significantly greater improvement in UPDRS motor scores in the IAMZ electrostimulation group compared to the IAMZ dry needling group (p < 0.001) and the sham electrostimulation (p < 0.001) groups. The improvement in UPDRS motor scores of the IAMZ electrostimulation group (ΔUPDRS = 5.29) reached moderate to high clinical significance, which was not the case for the dry needling group (ΔUPDRS = 1.54). In addition, both arms of the study demonstrated bilateral improvements in motor symptoms in response to unilateral IAMZ electrostimulation. Conclusion: The present study is the first demonstration of a potential role of IAMZ electrical stimulation in improving the clinical motor symptoms of PD patients in the short term.

Auditory startle reflex and startle reflex to somatosensory inputs in generalized dystonia.

OBJECTIVE: Startle reflex is a generalized defense reaction after unexpected auditory, visual, or tactile stimuli. Auditory startle reflex (ASR) and startle reflex to somatosensory inputs (SSS) have never been studied in generalized dystonia. Here, we aimed to study the characteristics and changes of ASR and SSS in this group. METHODS: We have examined ASR and SSS in patients with generalized dystonia (n=11) and healthy subjects (n=25) under the same conditions. ASRs and SSSs were recorded over the orbicularis oculi (O.oc), sternocleidomastoid, biceps brachii (BB), and abductor pollicis brevis (APB) muscles after bilateral auditory stimulation and unilateral median nerve electrical stimulation at the wrist, respectively. RESULTS: Both ASR and SSS showed the same sequence of muscle activation in both groups. However, the presence rates over the APB and BB muscles after both modalities of stimuli were significantly higher in the generalized dystonia group. ASR did not habituate in the dystonia group. CONCLUSIONS: Both ASR and SSS are disinhibited, and both show a similar sequence of muscle recruitment in generalized dystonia. SIGNIFICANCE: Higher probabilities over caudal muscles probably depend on the higher excitability of motor neurons secondary to central modulation.