The present invention relates to the use of polyunsaturated fatty acids and one or more components which have a beneficial effect on total methionine metabolism selected from the group consisting of vitamin B12 and precursors thereof, vitamin B6 and derivatives thereof, folic acid, zinc and magnesium, in the manufacture of a preparation for improving the action of receptors. This preparation is advantageously applied in patients suffering from Parkinson's disease, Huntington's chorea, epilepsy, schizophrenia, paranoia, depression, sleep disorders, impaired memory function, psychoses, dementia and ADHD.