Table 1.
Number of trials in which significant sternocleidomastoid (SCM) responses were observed.
| Subject | Acceleration | Deceleration | ||||||
|---|---|---|---|---|---|---|---|---|
| S+T+ | S+T− | S−T+ | S−T− | S+T+ | S+T− | S−T+ | S−T− | |
| 1 | 4 | 5 | 4 | 3 | 1 | 2 | 1 | 1 |
| 2 | 0 | 3 | 4 | 4 | 1 | 2 | 2 | 4 |
| 3 | 0 | 5 | 1 | 3 | 5 | 5 | 2 | 4 |
| 4 | 1 | 5 | 4 | 5 | 1 | 3 | 3 | 4 |
| 5 | 0 | 3 | 1 | 3 | 1 | 1 | 0 | 0 |
| 6 | 4 | 5 | 5 | 5 | 1 | 0 | 1 | 1 |
| 7 | 4 | 5 | 4 | 4 | 5 | 5 | 3 | 5 |
| 8 | 3 | 3 | 3 | 3 | 0 | 0 | 1 | 1 |
| 9 | 5 | 5 | 4 | 5 | 1 | 1 | 0 | 0 |
| 10 | 5 | 5 | 5 | 5 | 4 | 1 | 0 | 3 |
| 11 | 5 | 5 | 5 | 4 | 3 | 2 | 3 | 3 |
| Mean | 3.9 | 4.5 | 3.6 | 4.0 | 2.3 | 2.4 | 2.0 | 2.9 |
| SD | 2.1 | 0.9 | 1.4 | 0.9 | 1.8 | 1.7 | 1.2 | 1.8 |
The SCM response is an index of startling induced by the perturbations. Participants tended to show the startle response in trials under which they had no prior temporal knowledge for the perturbation (T− conditions) compared with that under which they knew the timing of the perturbation (T+ conditions).