APPARATUS FOR DETECTING, ANALYZING AND RECORDING BIOELECTRIC POTENTIALS

摘要

A means for monitoring electrophysiological activity is described having electrodes connected to an animal body with the output therefrom coupled to an amplifier which in turn feeds the amplified physiologically generated signal to a band pass filter network. The band pass filter is adapted to pass only those portions of the signals from the electrodes which occur in a predetermined frequency band. The filtered signal is coupled to an absolute value detector which produces a unidirectional output current signal the instantaneous amplitude of which corresponds to the instantaneous amplitude of the filter output signals. The detector output signal is coupled to a reversible microcoulometer which plates a metal from one electrode to another. The plating activity of the reversible microcoulometer produces a mass of plated material which is equivalent to the current-time integral, hence the average value, of the filter output signal. A readout device may be provided which causes the microcoulometer to operate in a reverse direction at a predetermined flow rate thereby causing a current of a predetermined value to flow. The value of the current-time integral may then be determined by determining the time required for the microcoulometer to operate in the reverse direction at the known current value. As an alternative, an event detection means may be provided which receives the signal from the electrodes and produces an output current signal of a known amplitude and duration or any signal producing a fixed, known charge for each occurrence of a predetermined wave form. In this mode of operation the reversible microcoulometer in effect operates as a counter with the amount of plating being equivalent to the number of occurrences of the predetermined wave form.