Effect of dopaminergic medication on PAS-induced modulation of the MEP amplitude with PD-on and-off.

<p>In PD patients, the average MEP amplitude in the right APB was significantly elevated after dopaminergic medication (*<i>P</i><0.05).</p

Patient demographic and clinical details.

<p>Patient demographic and clinical details.</p

MEG activity induced by MN stimulation in a subject under the rest condition.

<p>Bursts of 20-Hz activity were induced after right MN stimulation (A–C) and left MN stimulation (D–F). A, D: Signals were recorded from the channel over the left M1 after right MN stimulation (A) and over the right M1 after left MN stimulation (D). The signals were bandpass-filtered through 18–23 Hz. Vertical dashed lines indicate MN stimuli delivered once every 1.5 s. Note that the stimulus-induced 20-Hz activity is enhanced after a short suppression period. B, E: The 20-Hz activity was quantified by TSE method. TSE curves show the distribution of the 20-Hz activity after right MN stimulation (B) and after left MN stimulation (E). The curves show the time course of changes in the root-mean-square values of TSE signals from the gradiometer pair at each location from 0.2 s before the onset of the stimuli to 1.3 s after the onset. Vertical lines indicate the onset of the MN stimuli. The heads are viewed from the top. Note that prominent 20-Hz activity was induced in the left M1 corresponding to the hand area (encircled in B) and the right M1 corresponding to the hand area (encircled in E). C, F: The TSE curves obtained from the most reactive gradiometer pair encircled in B (C) and encircled in E (F). Ordinates, 20-Hz activity levels (fT/cm); abscissas, time before and after the onset of MN stimulation.</p

The mirror box used for producing mirror image of a hand holding a pencil.

<p>The subject inserted both hands into the box and viewed, through an opening in the top of the box, directly their hand holding a pencil or the mirror reflection of their hand holding a pencil. The unnecessary views of hands were prevented by using sliding boards on the top of the box. In this figure, a subject views the mirror image of her left hand. When the subject viewed directly their hand, transparent plastic was put in place of the mirror.</p

20-Hz activity in the M1 of a subject under each of the four experimental conditions.

<p>The MEG signals were recorded over the left M1 after right MN stimulation (A) and the right M1 after left MN stimulation (B) under experimental conditions (viewing the right hand, viewing the mirror image of right hand, viewing the left hand, and viewing the mirror image of left hand). The signals were bandpass-filtered through 18–23 Hz. Vertical dashed lines indicate MN stimuli delivered once every 1.5 s.</p

TSE curves obtained across 13 subjectes under each of the four experimental conditions.

<p>The TSE curves were obtained across 13 subjects in the left M1 (A) and the right M1 (B). Blue, green, orange, and red lines indicate TSE curves under the four experimental conditions: viewing the right hand, viewing the mirror image of right hand, viewing the left hand, and viewing the mirror image of left hand, respectively. The vertical axis shows TSE signal amplitude (fT/cm); the horizontal axis shows time before and after the onset of MN stimulation.</p

Schematic illustration of the experimental conditions.

<p>(A) viewing the mirror image of right hand: The subjects viewed the mirror image of their right hand holding a pencil. (B) viewing the right hand: The subjects viewed their right hand holding a pencil through transparent plastic. (C) viewing the left hand: The subjects viewed their left hand holding a pencil through transparent plastic. (D) viewing the mirror image of left hand: The subjects viewed the mirror image of their left hand holding a pencil. The hands covered with sliding boards are shown by white dashed lines on black background.</p

Mean pinching force changes in initial skill-training on Day 1 and mean acceleration changes in prepractice on Day 2.

<p>(A) Changes of the mean pinching force in the initial skill training between baseline (before session 1) and post session 3. Y axis indicates mean pinching force (kg). Error bars show the SD. *<i>P</i><0.05. (B) Mean accelerations in the motor prepractice between block 1 and block 4. Y axis indicates mean accelerations (cm/s²). Error bars show the SEM. N.S. not significant.</p

Experimental procedures.

<p>(A) Time schedule of experiments. Subjects were scanned for evaluating striatal dopamine levels using ¹¹C-raclopride PET on Day 1 (initial skill-training condition) and Day 2 (acquired condition). (B) ¹¹C-raclopride PET scanning. ¹¹C-raclopride (555 MBq) was injected into the right vein just before the emission data was acquired. They practiced rapid contraction of their left thumb via visual feedback during PET scanning. (C) Display seen by subjects during motor practice. Three coloured horizontal lines were graphically presented to help subjects understand the quality of their performance: peak acceleration of the present movement (blue), mean peak acceleration of all previous trials within a block (green) and maximum peak acceleration of all previous trials within a block (red).</p

¹¹C-raclopride BP changes in sub-regions of the striatum between the two conditions.

<p>Left panel shows the grass brain map of the voxel-based analysis of ¹¹C-raclopride BP change (upper figure: initial skill-training condition < acquired condition and lower figure: acquired condition < initial skill-training condition). Right panel shows coronal and axial sections of the statistical parametric map of ¹¹C-raclopride BP change in the initial skill-training condition versus acquired condition overlaying the MRI T1 image in stereotaxic space. Right side image corresponds to right side brain. The displayed cluster shows the significant area of decreased ¹¹C-raclopride BP in the right antero-dorsal and lateral part of the putamen. The peak coordinate in the right putamen was located at X = 30, Y = 4, Z = 12. No BP change was observed in the left putamen.</p