Effects of body mass index on plantar pressure and balance.

[Purpose] To suggest physiotherapy programs and to determine foot stability based on the results of plantar pressure and spontaneity balance in the normal group and in the obesity group according to the body mass index (BMI). [Subjects and Methods] The plantar pressure and balance of 20 females college students in their 20s were measured according to their BMI. BMI was measured by using BMS 330. The peak plantar pressure was measured in a static position in the forefoot and hind-foot areas. To study balance, the spontaneity balance of each foot was measured on both stable and unstable surfaces. [Results] In terms of plantar pressure, no significant change was observed in the forefoot and hind-foot peak pressure. In terms of spontaneity balance, no significant difference in foot position interaction was observed on both stable and unstable surfaces, while a significant difference was observed in the foot position between the groups. [Conclusion] The index of hind-foot spontaneity balance was low, particularly in the obesity group. This meant significant hind-foot swaying. The forefoot body weight support percentage increased to reinforce the reduced spontaneity balance index.

Effects of galvanic vestibular stimulation on event related potentials.

[Purpose] The purpose of this study was to examine the effects of galvanic vestibular stimulation on event-related potentials. [Subjects and Methods] Forty normal female adult subjects were randomly distributed to a galvanic vestibular stimulation application group (20 subjects) and sham group (20 subjects). For galvanic vestibular stimulation application, a positive electrode was applied to the right mastoid process, and a negative electrode was applied to the left mastoid process; simulation was applied for 10 minutes. A test was conducted on the N100 and P300 components of the event-related potentials before and after galvanic vestibular stimulation. [Results] The N100 latency showed statistically significant differences in interaction effects between time and group in the F3, F4, Fz, and Pz areas. The P300 latency showed the same results in the Fp1 and Fp2 areas, the N100 amplitude showed the same results in the Fp2, Fz, and Pz areas; and the P300 amplitude showed the same results in the Pz area. [Conclusion] These results suggest that galvanic vestibular stimulation may play a positive role in the N100 and P300 components of the event-related potentials of the cerebral cortex related to decision-making in matching words with images.

Effects of the Electrode Type on N100 and P300 in tDCS Applications.

[Purpose] This study investigated the effects of types of electrode on N100 and P300 in transcranial direct current stimulation (tDCS) applications. [Subjects and Methods] Thirty subjects were randomly assigned to two groups with 15 subjects in each group depending on the electrode types. A positive electrode on the primary motor area (C4) and a negative electrode on the left primary motor area (C3), and stimulation was applied for 20 minutes. Before and after tDCS, N100 and P300 were measured by attaching an electrode to Fp1 and Fp2. [Results] In tDCS applications, N100 and P300 showed no significant interaction effects between time and group for either latency or amplitude in the Fp1 and Fp 2 areas, but there was a statistically significant difference in the main effect duration. [Conclusion] The latencies of N100 and P300 were shortened and that their amplitudes increased in both the Fp1 and Fp2 areas, regardless of the type of electrode.