Disclosure no longer affected behaviour (6)
I believe the answer is:
expose
'disclosure' is the definition.
(expose is a kind of disclosure)
'no longer affected behaviour' is the wordplay.
'no longer' becomes 'ex'.
'affected behaviour' becomes 'pose'.
'ex'+'pose'='EXPOSE'
(Other definitions for expose that I've seen before include "Make visible or obvious" , "Uncover, expose to view" , "Make visible or apparent" , "Lay out to view" , "Lay open, reveal" .)