an exemplary embodiment is described below with reference to the accompanying drawings . it should be understood that the following description is intended to describe the exemplary embodiment , and not to limit the invention defined in the appended claims . fig1 depicts a universal system model of the high level functional flow for the control of hemifacial spasm , an exemplary embodiment . the desired need 10 is to inhibit aberrant signals reaching the muscles from the facial nerve ; the resources available are the sensors resident in the implanted or surface electrodes , the control collar which induces the magnetic fields and the controller which takes in the sensory data , and determines the proper response 11 based on current data , prior data and its outcome , and logic which determines the presence or absence of the lateral spread response and produces a voltage waveform which is expressed as a change in magnetic flux density by the coil collar which inhibits the facial nerve transmission for a specific time period and results 12 in the control of the target musculature . results of the intervention are fed back 13 to the controller which changes the timeframe in which the voltage waveform is applied for maximal benefit . for example , if no lateral spread is detected then no control output is created , but if a single millisecond control voltage waveform inhibits the spread response , then the controller will wait until it appears again . fig2 is an illustration of elements of the invention as applied to hemifacial spasm , an exemplary embodiment ; it is not drawn to scale . the implanted nerve control coil 21 consists of windings which when energized by a voltage from controller 20 produces a flux in proportion to amplitude and time derivative of the voltage wave . the control coil can consist of one or multiple coils located at optimal locations , for example on a node or nodes of ranvier which act like switching stations to re - establish the action potential lost in transmission to that point . controller 20 can be located in any convenient location , including externally , but is best positioned in the chest similarly to implantable caridoverter defibrillators , and even if internal it can be controlled , re - programmed , and re - charged externally . the sensors 22 of the nerve action potentials and muscle response can be single or muti - electrode connected to the controller via control wires 24 . sensory elements can include surface electrode probes 23 which are connected by wires or wirelessly to controller 20 . control cuff 21 can also be used as a sensor of either electric or magnetic fields , and can be connected by wires 28 to the controller 20 . depending on the nature and timing of the inputs derived from the sensors , for example the detection of a lateral spread response , from sensors 22 , 23 and sometimes 21 , the controller 20 produces voltage outputs 28 that are timed to intervene with the abnormal flow of action potential in the nerve . there types of possible controller voltage output waveforms 28 is large and situation dependent , but is most likely to be initially characterized by a sharp initial increase ( or sharp initial reverse current flow to create the opposite flux density in the cuff coil ) followed by a sharp decrease , or other casts by a more gradual decline . the timing of the outputs 28 can vary , but are likely to initially in the millisecond range . the number of pulse outputs will vary greatly depending on the type of intervention needed , and can be as few as one per detected abnormality . the results of the controller 25 voltage output waves are determined by the construction of the particular nerve cuff coil , which will change depending on the particular person , condition , and type of nerve being affected . because of faraday &# 39 ; s law , as discussed above , the electric potential difference between any two points in the nerve depends on the path taken to measure it . this means , non - intuitively , that the voltage waveforms within the nerve that are created by the flux change of the cuff coil 21 can simultaneously be positive in one area and negative in another , at least over the course of time in which the magnetic flux is changing . thus the ionic flow of the sensory and motor neurons within the nerve , of which there can be thousands , can , on a time - transient basis , be controlled at the same time even though they require the simultaneous imposition of voltages that could not be sustained in static environment . 1 . “ deep brain stimulation programming ” by montgomery , feb . 20 , 2006 . https :// mywebspace . wisc . edu / ebmontgomery / web / 2 . “ neuropsychiatry : rewiring faulty circuits in the brain ”, greg miller , page 1555 , science , vol 323 mar . 20 , 2009 . 3 . lecture , physics 8 . 02 spring 2002 , apr . 1 , 2002 and mar . 15 , 2002 by profs . walter lewin and john belcher . 4 . “ biomedical circuits and systems dedicated for sensing and neurostimulation : case study on urinary bladder dysfunctions ”. sawan et al : in the turkish journal of electrical engineering vol 16 , no 3 , 2008 . 5 . individually addressable crystalline conducting polymer nanowires in a microelectrode sensor array ” by wang , et al . nanotechnology 18 ( 2007 )
the invention is directed to a method of treating movement disorders by the modulation of neuronal transmission using time - variant non - conservative magnetic fields . the invention is also directed to a method for treating dystonias .