Nineteen euro needed for a shrink’s special cell (7)
I believe the answer is:
neurone
'special cell' is the definition.
(cell which transmits nerve impulses)
'nineteen euro needed for a shrink's' is the wordplay.
'for a shrink' says the answer is hidden in the clue (the clue must shrink down to just the answer).
'NEURONE' can be found hidden inside 'nineteen euro needed'.
(Other definitions for neurone that I've seen before include "Nerve centre" , "Cell that conducts nerve impulses" , "cell often seen with motor" .)