The variable resistor changes between two or more different resistance states by applying {HEAD ~ a voltage} between {TAIL ~ the electrodes} 
between
The variable resistor changes between two or more different resistance states by applying { HEAD ~ a voltage } between { TAIL ~ the electrodes }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL