Walton understandably credits Victor's condition to severe exposure; but
Victor tends to react with extreme stress to the Creature's presence and
more than once falls into a catatonic state: e.g., after the Creature's
original escape (1.4.7), after the
destruction of the second creature (3.3.7), and after the death of Clerval (3.4.4). This appears to be a
psychosomatic corollary to his constitutional introversion.