Identification of Double-Step Saccades Elicited by Auditory Double-Step Stimuli

Voluntary Saccadic eye movements can have visual, auditory, and auditory-visual bisensory origins. An experiment may be defined to examine how changing the type of sensory inputs and the number of them in a sequence reveals the type of the saccade generated by the oculo motor system; herein deemed single-step or double-step. 

This work reports design of experiments of double-step auditory stimuli played for human subjects, recording triggered saccadic eye movements, detecting each saccade, as well as estimating the saccade response characteristics, namely duration and latency. Based on the latency, then, it determines the type of the generated saccade by the subject through a clustering technique. We found that when doubling the amplitude of the two separate steps in double-step inputs, while keeping their duration unchanged, the number of triggered double-step saccades rises. 

The Standing Acoustic Wave Principle within the Frequency Analysis of Acoustic Signals in the Cochlea

The organ of hearing is responsible for the correct frequency analysis of auditory perceptions coming from the outer environment. The article deals with the principles of the analysis of auditory perceptions in the cochlea only, i.e., from the overall signal leaving the oval window to its decomposition realized by the basilar membrane. The paper presents two different methods with the function of the cochlea considered as a frequency analyzer of perceived acoustic signals. 

First, there is an analysis of the principle that cochlear function involves acoustic waves travelling along the basilar membrane; this concept is one that prevails in the con temporary specialist literature. Then, a new principle with the working name “the principle of standing acoustic waves in the common cavity of the scala vestibuli and scala tympani” is presented and defined in depth. According to this principle, individual structural modes of the basilar membrane are excited by continuous standing waves of acoustic pressure in the scale tympani.