<unk>  measurement in human. The main three parts of the procedure are<unk> , startle stimulus, and startle reflex. Different<unk> -to-pulse intervals, or lead intervals, are used: 30, 60, 120, 240 and 480 ms. Lead interval counts from the start of<unk>  to the start of the pulse. With the interval exceeding 500 ms,<unk>  facilitation – increased response – is most likely to follow. A burst of white noise is usually used as the acoustic startle stimulus. Typical durations are 20 ms for<unk>  and 40 ms for pulse. Background noise with 65-70 dB is used in human studies, and 30–40 dB in rodent experiments.<unk>  is typically set 3–12 dB louder than background. Startle response is measured in rodents using the so-called automated "startle chambers" or "stabilimeter chambers", with detectors recording whole-body reaction. In humans, the movements of oculomotor muscles ("eye-blink reflex" or "eye-blink response" assessed using electromyographic recording of orbicularis oculi muscle and by oculography) could be used as a measure. Pulse-alone results are compared to<unk> -plus-pulse, and the percentage of the reduction in the startle reflex represents<unk> . Possible hearing impairment must be taken into account, as, for example, several strains of mice develop high frequency hearing loss when they mature. The recorded signal needs to be passband filtered between 28 Hz and 500 Hz. By this step, artifacts from eye movements and muscle activity independent of blink responses are removed. To avoid aliasing artifacts the sampling rate of the signal should be at least 1024 Hz which is larger than twice the upper bound of the bandpass filter (twice the Nyquist frequency). After filtering, the resulting signal is rectified and smoothed. Reporting the signal deflection evoked by the startle stimulus, the term mean amplitude (mA) refers to the average startle response excluding nonresponse trials. However, to calculate the mean magnitude (mM), nonresponse trials are set to zero before averaging. Dividing the number detected responses (number of trials used to compute amplitude) by the total number of eliciting stimuli yields the response probability (P). Thus, increasing response probability shifts average response magnitude towards average response amplitude. It is recommend to use the computed mean magnitude to report the average startle response. Since this metric includes also nonresponse measures, it exhibits increased validity compared to mean amplitude.
Prepulse inhibition
Burst suppression
Lateral inhibition
Spike-timing-dependent plasticity
Fencing response
Intermuscular coherence
Disinhibition
Counterstimulation