The Collaborative International Dictionary of English v.0.48:

Psychophysical \Psy`cho*phys"ic*al\, a.
   Of or pertaining to psychophysics; involving the action or
   mutual relations of the psychical and physical in man.
   [1913 Webster]

   Psychophysical time (Physiol.), the time required for the
      mind to transform a sensory impression into a motor
      impulse. It is an important part of physiological or
      reaction time. See under Reaction.
      [1913 Webster]