AIM: To explore the characteristics of motor evoked potential(MEP) and cortical excitability in Parkinson's disease by transcranial magnetic stimulation(TMS).METHODS: 20 normal volunteers were enrolled as control(group A),with the average age of(62.3?16.7) year old ranged from 52 to 79 years including 12 males and 8 females.MEP were assessed and compared separately between left and right hemispheres.21 patients with Parkinson's disease(PD) in asymmetry symptoms were performed in this study(group B),with the average age of(63.3?16.7) year old ranged from 46 to 80 years including 12 males and 9 females.UPDRS motor scores(UPDRSⅢ) were assessed before the check of cortical excitability(MEP).Motor evoked potentials(MEP) was assessed and compared separately on the minor and the serious bodyside,compared to control group.RESULTS: The indexes of MEP from both sides of normal control had no significant diversity.Amp was increased and both rest motor threshold(RMT) and cortical latency(CL) were also decreased significantly in PD patient compared to the normal control.On the serious side of PD,RMT decreased significantly compared to the minor side.Amp,CL and central motor conduct time(CMCT) changed without significant diversity between minor and serious bodyside.CONCLUSION: The motor cortical excitability is increased in PD patients.The excitability is higher with the more serious symptom side.The character of MEP in PD patients may be helpful to make a diagnosis and evaluate the severity of symptoms.

Adult ; Aged ; Chromosome Aberrations ; Epilepsies, Myoclonic ; diagnosis ; genetics ; Female ; Humans ; Male ; Middle Aged ; Pedigree