Given support when in bed (5)
I believe the answer is:
based
'given support' is the definition.
The definition and answer can be both related to thinking as well as being past participle verbs.
Maybe they are linked in a way I don't understand?
'when in bed' is the wordplay.
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'in' is an insertion indicator.
'as' put inside 'bed' is 'BASED'.
Can you help me to learn more?
(Other definitions for based that I've seen before include "Positioned" , "Established" , "Stationed (in a place)" , "Founded, grounded" , "(Of aircraft) stationed" .)