Different versions of the TDU.

<p>Left: the generic version of 12×12 electrodes; center: A miniaturized version of 6×6 electrodes; right: our wireless version (6×6 electrodes).</p

Summary of raw data of Experiment 1 (mean±SE).

<p>Note: * means a significant difference given (post-hoc Tukey test; <.05).</p

Figure 1

<p>Schematic view of haptic guidances: (a) Haptic guidance in position (HGP); the force felt by the user at time <i>t</i> is proportional to displacement between the current user position and the theoretical position on the model trajectory; (b) Haptic guidance in force (HGF); the force felt by the user at time <i>t</i> is the same as the force existing for the theoretical trajectory at the same time.</p

Letters proposed in experiment 1: Letters 1 and 2 are Arabic and letters 3 and 4 are “Japanese-like” letters.

<p>Letters proposed in experiment 1: Letters 1 and 2 are Arabic and letters 3 and 4 are “Japanese-like” letters.</p

Patterns of electrostimulations.

<p>Electrodes in the front, back, left or right part of the tongue are activated when a displacement of the chest respectively in the back, front, right and left direction is suitable.</p

Results.

<p>(a) Global results: Postural behaviors for all trials in percentage: in white, correct behaviors; in light gray, displacement in the correct direction but not far enough; in dark gray, no movement; in black, movements in the wrong direction. (b) Mean and standard deviation of the overpressured volume (OV) of the region of interest Arisk before and after electrostimulation observed (*: p<0.05); (c) Mean and standard deviation of pressure reduction for each predetermined range of high pressures (*: p<0.05).</p

Relation between postures and pressure distributions. Sample of pressure distributions (right) corresponding to nine seated postures (left).

<p>Accessible postures: From actual posture (BR for instance), only four pre-recorded postures (CR, FR, B and BL) are reachable by a simple unidirectional movement (forward or left in this case).</p

General principle of biofeedback and behavior of the subject.

<p>(a) Mean pressure distribution after a random timing; (b) Color values; (c) Pressures into the region of interest (pressures above 100 mmHg); (d) Pressure map at the beginning of the stimulation; (e) Estimated posture in red (corresponding to map (d)) and target posture estimated to be safe in green; (f) Directional order sent on the TDU; (g) Pressure map measured at the end of stimulation; (h) Position at the end of the stimulation, fitting the target one (in red); (i) Pressure in the region of interest at the end of the stimulation.</p

Pressure map.

<p>the VistaMedical Ltd. pressure mapping system connected to a laptop.</p

Figure 2

<p>System overview: (a) The modified stylus pen; (b) The graphic User Interface displayed to the subject; (c) A subject undergoing training on the WYSIWYF interface.</p