Accommodation: the rise in the threshold during the passage of a constant, direct electric current because of which only the make and break of the current stimulates the nerve.3
Habituation: 1.) the gradual adaptation to a stimulus. 2.) extinction or decrease of a conditioned reflex over time by repetition of the conditioned stimulus.3
Afferent neurons exhibit phenomenon known as neuronal habituation, where refractoriness develops to repeated stimuli.30 The nerve no longer responds to predictable signals and either ignores them or develops alternative neural pathways to circumvent the stimuli and continue to transmit pain or aberrant signals to the CNS. Therefore, bombarding tissue with repeated, uniform and predictable signals rapidly become useless in stimulating nerve fibers to release secretions.
Law of Dubois-Reymond: To electrically stimulate a nerve, there must be a sudden variation in current flow to prevent accommodation.
Systematic variation of the pulse amplitude, frequency, interval, and clustering such that no two impulses exhibit the same waveform, discourages neural habituation. In the course of treatment, waveforms emitted from certain modes in BEST devices are continuously changing (if it is repeated, it reappears only after a lengthy interval). Moreover the impedance of the tissue is constantly changing the waveform of the next emitted signal to ensure a different waveform until equilibrium is achieved, at which point a maximum dose of signaling has been delivered.
An important response to a BEST impulse is the release of regulative neuropeptides and cytokines. The signal stream, comprising waveform, signal strength, voltage, current, and frequency, can be varied in a number of ways, either through preselection by the operator or automatically by the software programmed into the device. The “dosage” can be delivered automatically or overridden at the discretion of the operator, with guidance from visual and audio indicators. Digital LED and sound displays or both give guidance to the operator as dynamic real-time indicators of function and endpoint achievement of objectives.
A single pulse may be preselected for a specific repeat rate over a specific frequency range. The signal may also be “modulated” either by altering the ratio of “time-on” to “time-off” signaling or by changing the pulse waveform by selecting one of a series of set damping factors. These “modulations” can either be applied individually or together. Each individual impulse can be adjusted for amplitude, frequency, and dampened waveform.
A cluster of pulses may be packaged into discrete bursts and may be repeated at a fixed or varying frequencies and intervals. The individual pulses in these cluster bursts themselves can be modulated for either random or periodic interval spacing to give a concentrated (deep) or diffuse (shallow) penetration.
Automatic cycling of both the pulse interval rate over a set frequency range and the waveform-damping factor is also possible. These cyclical modes can again be utilized either individually or together.
The power output can be set by the operator to be detectable but comfortable for the patient. It can also be adjusted during application should this be desired. These impulses have been tailored to mimic the electrical discharges of the nervous system in order to elicit the organism’s response with optimum efficiency and minimum disruption to cell function, depending upon the unique requirements of the presenting pain disease dynamics (or lack of same).
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