In this randomized controlled trial , 65 non-demented patients with PD according to UK Brain Bank criteria ( Hoehn & Yahr I-III ) were allocated to one of two cognitive multi-component treatments ( `` NEUROvitalis '' , a structured training , or the unstructured training `` Mentally fit '' with randomly assembled cognitive tasks , each including 12 group-sessions 90min over 6 weeks ) or a waiting list control group ( CG ) .