The Collaborative International Dictionary of English v.0.48:

left-brained \left"-brained`\, a.
   Exhibiting intellectual or personality characteristics
   suggesting dominance of linguistic or logical modes of
   thought, which are usually controlled by the left cerebral
   hemisphere; as, left-brained pedants unable to appreciate
   music; also referred to as linear. See linear[3].
   Contrasted with right-brained.
   [PJC] left field