( However ( , ( ( in ( most cases ) ) ( , ( ( SCN lesions ) ( ( ( fail ( to ( clock ( circannual rhythms ) ) ) ) ( even ( though ( ( circannual rhythms ) ( are lost ) ) ) ) ) . ) ) ) ) ) )
(ROOT (S (ADVP (RB However)) (, ,) (PP (IN in) (NP (JJS most) (NNS cases))) (, ,) (NP (NNP SCN) (NNS lesions)) (VP (VBP fail) (PP (TO to) (NP (NN clock) (NN circannual) (NNS rhythms))) (SBAR (RB even) (IN though) (S (NP (JJ circannual) (NNS rhythms)) (VP (VBP are) (VP (VBN lost)))))) (. .)))
However, in most cases, SCN lesions fail to clock circannual rhythms even though circannual rhythms are lost.
(ROOT (S (NP (JJ Circannual) (JJ behavioral) (NNS rhythms)) (VP (VBP are) (VP (VBN linked) (PP (TO to) (NP (NP (DT the) (JJ yearly) (NN cycle)) (PP (IN of) (NP (NNS seasons))))))) (. .)))