The Collaborative International Dictionary of English v.0.48:

Involuntariness \In*vol"un*ta*ri*ness\, n.
   The quality or state of being involuntary; unwillingness;
   automatism.
   [1913 Webster]

WordNet (r) 3.0 (2006):

involuntariness
    n 1: the trait of being unwilling; "his unwillingness to
         cooperate vetoed every proposal I made"; "in spite of our
         warnings he plowed ahead with the involuntariness of an
         automaton" [syn: unwillingness, involuntariness] [ant:
         willingness]