The displacement values may be employed to produce a signal indicative of a respiration phase that can be used in {HEAD ~ connection} with {TAIL ~ motion artifact reduction techniques} 
The displacement values may be employed to produce a signal indicative of a respiration phase that can be used in { HEAD ~ connection } with { TAIL ~ motion artifact reduction techniques }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL