Periods of confusion, we hear (4)
I believe the answer is:
days
'periods' is the definition.
(I've seen this before)
'confusion we hear' is the wordplay.
'confusion' becomes 'daze' (daze is a kind of confusion).
'we hear' indicates a 'sounds like' (homophone) clue.
'daze' is a homophone of 'DAYS'.
'of' acts as a link.
(Other definitions for days that I've seen before include "Sevenths of a week" , "Periods of 24 hours" , "Periods (of week)" , "See 7 and 18" , "See 25" .)