The present invention relates to a pharmaceutical composition comprising an inhibitor of acetylcholinesterase (AChE inhibitor) and a metabotropic glutamate receptor 2 antagonist (mGluR2 antagonist) and a pharmaceutically acceptable excipient. The invention also relates to a method of treating and/or preventing acute and/or chronic neurological disorders comprising administering to a patient in need of such treatment and/or prevention a therapeutically effective amount of said AChE inhibitor and mGluR2 antagonist as well as a kit comprising said AChE inhibitor and mGluR2 antagonist. In particular, the mGluR2 antagonist relates to the compound of formula I wherein, R1, R2, R3, X and Y are described hereinabove. The combination of the AChE inhibitor and mGluR2 antagonist is useful for treating and/or preventing chronic neurological disorders. These disorders include Alzheimer's disease and mild cognitive impairment.