Evaluation of startle response and prepulse inhibition based on changes in the range of vertical pressure force of the feet on the ground: a preliminary study.

The aim of the study was to evaluate the possibility of estimating a startle response and sensorimotor gating based on changes in the range of vertical pressure force of the feet on the ground during a dynamometric examination. The study encompassed 13 healthy and physically fit men (age: 23.3 ± 2.0 years; height: 178.0 ± 6.1 cm; and weight: 76.1 ± 9.0 kg). The inhibitory mechanisms of startle reflex were used as the measure of sensorimotor gating. It was triggered by a strong acoustic stimulus (106 dB SPL, 40 ms), which was preceded by a similar, weaker signal (80 dB SPL, 20 ms). Startle reflex was evaluated using a piezoelectric force platform. The results of the conducted study show that the range of vertical pressure force of the feet caused by the reaction to a strong acoustic stimulus is significantly smaller when this stimulus is preceded by a signal of lower intensity (prepulse). Such assessment is only possible with the participants' eyes open. The generalized startle response of a person may be estimated using a force platform, based on changes in the range of vertical pressure force of the feet on the ground, which are caused by unexpected acoustic stimuli. There is a strong indication that using a force platform to evaluate sensorimotor gating could be used as an alternative to electromyographic examinations.