( ( in ( a ( positive feedback ) ) ) ( physiological ( response . ) ) )
(ROOT (FRAG (PP (IN in) (NP (DT a) (JJ positive) (NN feedback))) (NP (JJ physiological) (NN response) (. .))))
in a positive feedback physiological response.
(ROOT (S (NP (JJ Positive) (NN feedback)) (VP (VP (VBZ intensifies) (NP (NP (DT a) (NN change)) (PP (IN in) (NP (NP (DT the) (NN body) (POS 's)) (JJ physiological) (NN condition))))) (CONJP (RB rather) (IN than)) (VP (VBG reversing) (NP (PRP it)))) (. .)))