ASA significantly correlated to the AI of DAT binding values of the putamen (see, Methods).

<p>ASA significantly correlated to the AI of DAT binding values of the putamen (see, Methods).</p

Spatio-temporal parameters of the stride, arm ROM and phase shift of subjects with Parkinson disease and healthy subjects.

<p>Median values, non-outlier min-max, and levels of statistical difference (Mann-Whitney U-test or Matched pairs) are reported. Data refer at walking at different velocities unless otherwise specified.</p>*<p>p<0.05 (PD vs. HC); ** p<0.01 (PD vs. HC). BH = body height (mm). ROM = range of motion; Phase shift = temporal delay (%stride) between the positive peak (antero-posterior swing) of the wrist and the negative peak of malleolus; Stride = the period from initial contact of one foot and following initial contact of the same foot, is one gait cycle. Stance = gait phase when a foot is in contact with the ground, it begins with initial heel contact and ends with toe off.</p><p>For Parkinson patients, ipsilateral and contralateral refers to the more dopamine depleted hemisphere. For healthy controls, left hemibody refers conventionally to ipsilateral.</p

Correlation between phase shift modulation at different gait velocities and DAT binding values of the putamen (A) and caudate nucleus (B).

<p>Full dots represent arms with reduced (<18°) ROM when walking at preferred gait speed. Empty dots shows arms with arm ROM within the normal range. When arm ROM was reduced, a positive correlation was found between upper-lower limb phase shift modulation and both DAT binding values of putamen (RSquare = 0.37, p = 0.01) and caudate nucleus (RSquare = 0.38, p = 0.01). Correlation lines for arms with normal ROM (>18°) are not shown.</p

EMG recordings (RMS).

<p>Imb. = Imbalance; Unl. = Unloading; SOL = Soleus muscle; TA = Tibialis anterior muscle; p values refers to Wilcoxon-Mann-Whitney U Test.</p

Kinematic measurements.

<p>AP = Antero-posterior; ML = Medio-materal. Imb. = Imbalance; Unl. = Unloading; FL = foot length; BH = body height; SWto = Heel-off of the swing foot. p values refers to Wilcoxon-Mann-Whitney U Test.</p

Demographic and clinical characteristics.

<p>Demographic and clinical characteristics.</p

Recorded data at gait initiation.

<p>Centre of pressure (CoP, black line) and centre of mass (CoM, dashed line) displacement in a healthy subject (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g001" target="_blank">figure 1</a> left) and child with RTT (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g002" target="_blank">figure 2</a> left) with corresponding EMG activity of tibialis anterior (TA) and soleus muscles (SOL) of swing and stance foot (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g001" target="_blank">figure 1</a> right and 2 right). The dotted line (in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g001" target="_blank">figure 1</a> left and 2 left) shows CoP-CoM distance at toe-off of the swing foot (SWto). In <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g001" target="_blank">figure 1</a> (right), arrows indicate bilateral suppression of the tonic activity of SOL which, together with the subsequent activation of TA, is responsible for the backward displacement of the CoP. This synergistic activity of pairs of postural muscles (i.e. TA and SOL) is not present in RTT girls (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092736#pone-0092736-g002" target="_blank">figure 2</a> right). <i>Imbalance phase</i>, from the instant APAonset, at which the CoP start moving backward, to the instant of heel-off of the swing foot (SWho). <i>Unloading phase</i>, from SWho to toe-off of the swing foot (SWto). STto is the instant of toe-off of the stance foot.</p

Modulation of the spectral power during the gait cycle.

<p>Event related synchronization (ERS) and desynchronization (ERD) in low <i>β-</i> (top) high <i>β-</i> (middle) and <i>γ</i>-frequency band (bottom). Subthalamic power changes of the phases of gait are shown as the average relative change of the whole stride of all subjects. Shaded areas represent the confidence intervals (5–95%) of the group mean. We analyzed the power changes of STN–and STN+ during the gait cycle of the contralateral foot (but they could be also referred to the matched gait phases of the ipsilateral one). Stance is the period during which the foot is on the ground (dark and light orange bars). The stance phase includes a period of bilateral foot contact with the floor (double-support phases [dark orange bars]), and a period of unilateral foot contact (single-support phase [light orange bar]). The swing phase (light green and dark green bars) is the interval in which the foot is lifted from the floor. Thanks to the velocity peak (VP) of the marker placed on the lateral malleolus, we identified an acceleration (light green) a deceleration (dark green) sub-phase of the swing phase. HS = heel strike; TO = toe off; VP = velocity peak; lower case subscript indicates the foot contralateral _(contra) or ipsilateral _(ipsi) to STN–or STN+.</p

Inter-hemispheric coherence.

<p>Inter-hemispheric coherence (Coh, top panel), phase locking value (PLV, bottom left plot) and amplitude cross-correlation (CC, bottom right plot) during resting state (blue line), upright standing (pink line) and walking (green line). Statistical significance (red bar, paired Wilcoxon test, <i>p</i><0.05 uncorrected) was reached for the PLV selectively in the <i>β</i>-frequency band between resting state and walking. Shaded areas represent the confidence intervals (5–95%) of the group mean.</p

Spectral profiles (single subject) during resting, upright standing and gait.

<p>Single subject spectral power of the STN local field potential during resting (blue line), standing (pink line) and gait for the two hemispheres, with less (–) and more (+) striatal dopamine innervation. Axial slices are left-right flipped to match the corresponding STN. The peak at 32 Hz is a known artefact of the Activa PC+S^® system tied to clock settings or due to a triggered check of the battery status. SPECT scans (central column) show striatal dopaminergic loss as percentage decline with respect to healthy subjects (calculated from BP_ND of DAT, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0198691#pone.0198691.t003" target="_blank">Table 3</a>).</p