The present invention is concerned with 2-oxo-2,3-dihydro-indoles of general formula (I) wherein Ar1 is phenyl or a five or six membered heteroaryl group, containing one, two or three heteroatoms, selected from N, S or O, wherein the N-heteroatom in the heteroaryl group may be oxidized to N+-(O-); R1 is lower alkyl, halogen, cyano or cycloalkyl; Ar2 is a five or six membered heteroaryl group, containing one, two, three or four heteroatoms, selected from N, S or O, wherein the N-heteroatom in the heteroaryl group may be oxidized to N+-(O-), or is benzo[b]thiophenyl; R2 is hydrogen, lower alkyl, halogen, cyano, lower alkyl substituted by hydroxyl, lower alkyl substituted by halogen, lower alkyl substituted by amino, lower alkyl substituted by alkoxy, lower alkyl substituted by amide, or is cycloalkyl; X is CH or N; n is 1 or 2; m is 1 or 2; as well as with a pharmaceutically acceptable salt thereof, with a racemic mixture, or with its corresponding enantiomer and/or optical isomer and/or stereoisomer thereof. The compounds may be used in the treatment of CNS diseases related to positive (psychosis) and negative symptoms of schizophrenia, substance abuse, alcohol and drug addiction, obsessive-compulsive disorders, cognitive impairment, bipolar disorders, mood disorders, major depression, treatment resistant depression, anxiety disorders, Alzheimer's disease, autism, Parkinson's disease, chronic pain, borderline personality disorder, neurodegenerative disease, sleep disturbances, chronic fatigue syndrome, stiffness, inflammatory disease, asthma, Huntington's disease, ADHD, amyotrophic lateral sclerosis, epilepsy, effects in arthritis, autoimmune disease, viral and fungal infections, cardiovascular diseases, ophthalmology and inflammatory retinal diseases and balance problems.