Objective: To explore the dynamic change of the late attentional selection process under linearly varied vestibular stimuli using event-related potentials (ERPs) technique.
Method: Thirty-three subjects participated in the experiment. They were exposed to vestibular stimulation of constant angular velocity rotation (10 degrees/s) and four levels of constant angular acceleration rotation, the acceleration was 0.6 degrees/s2, 0.8 degrees/s2, 1.0 degrees/s2, 1.2 degrees/s2 respectively. The same auditory go/no-go cognitive task was done during the stimulation. The task involved verbally given Chinese digit number from two to nine with 1000 ms random interval. Subjects were asked to push the button for the odd numbers (target) and withhold to the even numbers (non-target).
Result: Compared with control and different level of constant angular acceleration rotation, the N2 amplitude of non-target ERPs (NT-ERPs) decreased significantly over anterior-central scalp during 10 degrees/s constant rotation, but the N2 amplitude of target ERPs (T-ERPs) reduced significantly only at F4, F(Z) and T4 sites. The P3 latency of T-ERPs decreased significantly in 10 degrees/s constant rotation in contrast with control. Under four different acceleration level, the P3 latency of T-ERPs was relatively longer in 0.8 degrees/s2 and 1.0 degrees/s2, but shorter in 0.6 degrees/s2 and 1.2 degrees/s2.
Conclusion: Constant angular velocity rotation had an activating effect on late attentional selection process. In contrast to the activation effect of constant angular velocity rotation, constant angular acceleration had an inhibition effect on the cognitive processes and this inhibition effect may have several levels.