## 3 Results
### Superimposition of Touch Displacement on Habituated Acoustic Startle Responses
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline  & & \multicolumn{4}{c}{**Stimulus**} & \multicolumn{4}{c}{**Statistical Results**} \\ \hline A & S\({}_{1}\) & S\({}_{8-10}\) & D\({}_{1}\) & D\({}_{5}\) & C\({}_{1}\) & C\({}_{5}\) & \(n\) & Main Effect & Tukey’s HSD (\(p<0.05\)) \\
**Mechanical** & & & & & & & & & \\ \(\Delta\)COP\({}_{\rm AP}\) (mm) & 1.0 (2.7) & 0.8 (0.6) & 5.2 (1.1) & 1.0 (0.7) & 6.7 (2.4) & 3.4 (1.3) & 8 & 2.07 (\(p=0.093\)) & \\ \(\Delta\)Elbow (deg) & 0.1 (1.2) & \(-\)0.2 (0.3) & \(-\)0.9 (0.3) & 2.0 (0.4) & \(-\)3.9 (1.4) & 3.3 (1.4) & 5 & 5.65 (\(p=0.002\)) & D\({}_{5}>\) C\({}_{1}\), C\({}_{1}<\) C\({}_{5}\) \\
**EMG \%MVC** & & & & & & & & \\ TA & 2.1 (0.8) & 1.1 (0.4) & 4.2 (1.5) & 0.7 (0.5) & 12.0 (3.0) & 4.6 (2.2) & 8 & 8.03 (\(p=0.000\)) & D\({}_{5}<\) C\({}_{1}\), C\({}_{1}>\) C\({}_{5}\) \\ AD & 5.1 (3.1) & 1.5 (0.6) & \(-\)0.2 (0.3) & 2.7 (0.7) & 18.5 (4.9) & 7.9 (2.1) & 7 & 8.78 (\(p=0.000\)) & D\({}_{5}<\) C\({}_{1}\), C\({}_{1}>\) C\({}_{5}\) \\ SCM & 13.9 (4.4) & 7.5 (3.6) & \(-\)0.3 (0.5) & 0.5 (0.6) & 19.1 (6.8) & 11.1 (5.3) & 7 & 4.87 (\(p=0.002\)) & D\({}_{5}<\) C\({}_{1}\) \\ CO & 21.1 (1.0) & 23.0 (0.8) & 2.1 (1.0) & 2.5 (1.1) & 27.6 (14.4) & 25.8 (10.6) & 8 & 3.29 (\(p=0.015\)) & D\({}_{5}<\) C\({}_{1}\) \\
**Statistics** & & & & & & & & & \\
**Mechanical** & & & & & & & & \\ \(\Delta\)COP\({}_{\rm AP}\) (mm) & 0.8 (0.6) & \(-\)0.1 (0.8) & 5.4 (0.7) & 0.1 (1.2) & 0.6 (1.0) & 0.5 (1.6) & 8 & 5.64 (\(p=0.001\)) & S\({}_{8-10}<\) C\({}_{1}\), C\({}_{1}>\) C\({}_{5}\) \\ \(\Delta\)Elbow (deg) & \(-\)0.1 (0.4) & \(-\)0.2 (0.2) & -2.0 (0.6) & 2.6 (1.0) & 1.2 (0.6) & 2.2 (1.0) & 5 & 6.57 (\(p=0.000\)) & C\({}_{1}<\) C\({}_{5}\) \\
**EMG \%MVC** & & & & & & & & \\ TA & 2.8 (1.2) & 0.7 (0.4) & 6.9 (1.9) & 8.0 (2.6) & 0.9 (0.7) & 1.5 (1.3) & 7 & 5.27 (\(p=0.001\)) & S\({}_{8-10}<\) C\({}_{1}\), C\({}_{5}>\) D\({}_{1}\) \\ AD & 1.1 (0.4) & 0.9 (0.2) & 2.3 (1.6) & 3.3 (1.4) & 1.5 (0.5) & 1.3 (0.5) & 7 & 1.12 (\(p=0.373\)) & \\ SOM & 8.4 (3.1) & 2.9 (1.5) & 5.0 (2.8) & 6.3 (3.0) & \(-\)0.1 (0.3) & \(-\)0.4 (0.3) & 7 & 2.74 (\(p=0.034\)) & \\ CO & 11.3 (3.7) & 12.9 (5.0) & 18.7 (6.8) & 18.5 (5.7) & 0.5 (0.4) & 1.1 (0.8) & 7 & 5.61 (\(p=0.001\)) & C\({}_{5}>\) D\({}_{1}\) \\ \hline \end{tabular} Values are means (SE), COP\({}_{\rm AP}\), center of pressure anterior-posterior; TA, tibialis anterior; AD, anterior deltoid; SCM, stereomelodanstoid; CO, otickularis could; D, touch displacement; S, starfree C, combined; MVC, maximum voluntary contraction. Statistical results are _r_statistics and _r_values. [PERSON]’s HSD applied to adjacent points in sequence only.  
\end{table} 
Table 3: Change in COP\({}_{\rm AP}\) position and elbow angle, and normalized muscle response amplitudes. In Figure 8B, group averaged data are shown for participants who received the STARTLE initially, followed by the COMBINED stimuli. STARTLE did not result in a consistent impact on the COP\({}_{\text{AP}}\) and no demonstrable change in elbow angle, across participants. This was contrasted by bursts of EMG activity observed in each of the four muscles depicted. In TA, an initial burst (Trial 1 = 2.8 \(\pm\) 1.2% MVC) decreased with repeated exposures (Trials 8-10 = 0.7 \(\pm\) 0.4% MVC), whereas in AD a small initial burst (Trial 1 = 1.1 \(\pm\) 0.4% MVC) showed little adaptation over repeated trials (Trials 8-10 = 0.9 \(\pm\) 0.2 % MVC). A marked initial burst in SCM (Trial 1 = 8.4 \(\pm\) 3.1% MVC) decreased with repeated trials (Trials 8-10 = 2.9 \(\pm\) 1.5 % MVC). In contrast, pronounced initial bursts in OO (Trial 1 = 11.3 \(\pm\) 3.7% MVC) were largely unchanged with repeated STARTLE exposure (Trials 8-10 = 12.9 \(\pm\) 5.0% MVC). Subsequently, the DISPLACEMENT was superimposed with these habituated STARTLE responses. The initial COMBINED stimulus resulted in a forward sway (Trial 11 = 5.4 \(\pm\) 0.7 mm), with an elbow flexion (Trial 11 = 2.0 \(\pm\) 0.6\({}^{\circ}\)).