ABSTRACT
The Rolandic beta rhythm, at â¼20 Hz, is generated in the somatosensory and motor cortices and is modulated by motor activity and sensory stimuli, causing a short lasting suppression that is followed by a rebound of the beta rhythm. The rebound reflects inhibitory changes in the primary sensorimotor (SMI) cortex, and thus it has been used as a biomarker to follow the recovery of patients with acute stroke. The longitudinal stability of beta rhythm modulation is a prerequisite for its use in long-term follow-ups. We quantified the reproducibility of beta rhythm modulation in healthy subjects in a 1-year-longitudinal study both for MEG and EEG at T0, 1 month (T1-month, n = 8) and 1 year (T1-year, n = 19). The beta rhythm (13-25 Hz) was modulated by fixed tactile and proprioceptive stimulations of the index fingers. The relative peak strengths of beta suppression and rebound did not differ significantly between the sessions, and intersession reproducibility was good or excellent according to intraclass correlation-coefficient values (0.70-0.96) both in MEG and EEG. Our results indicate that the beta rhythm modulation to tactile and proprioceptive stimulation is well reproducible within 1 year. These results support the use of beta modulation as a biomarker in long-term follow-up studies, e.g., to quantify the functional state of the SMI cortex during rehabilitation and drug interventions in various neurological impairments.NEW & NOTEWORTHY The present study demonstrates that beta rhythm modulation is highly reproducible in a group of healthy subjects within a year. Hence, it can be reliably used as a biomarker in longitudinal follow-up studies in different neurological patient groups to reflect changes in the functional state of the sensorimotor cortex.
Subject(s)
Beta Rhythm/physiology , Electroencephalography Phase Synchronization/physiology , Electroencephalography , Evoked Potentials/physiology , Magnetoencephalography , Motor Cortex/physiology , Proprioception/physiology , Somatosensory Cortex/physiology , Touch Perception/physiology , Adult , Electroencephalography/standards , Female , Humans , Longitudinal Studies , Magnetoencephalography/standards , Male , Reproducibility of Results , Young AdultABSTRACT
OBJECTIVE: To study the cutaneous toxicity of Compound p-cymene cream.METHODS: Different dosage of Compound p-cymene cream was applied on normal skin and the damaged skin of hairless area of rabbits,and the presence of acute toxicity.RESULTS: Compound p-cymene cream induced neither acute toxicity nor cutaneous irritant reaction.CONCLUSION: Compound p-cymene cream is a safe locally applied external preparation.
