Disclosed herein are carboxamide inhibitor compounds of phosphodiesterase type 10A of the general formula (I), wherein the substituents are as described in the specification. Also disclosed is the use of compounds of formula (I) for treating or controlling neurological and psychiatric disorders which can be treated by inhibition of phosphodiesterase type 10A such as curative treatment, control or amelioration and prophylaxis, CNS disorders, in particular schizophrenia, depression, bipolar disorders, cognitive dysfunctions associated with schizophrenia, cognitive dysfunctions associated with Alzheimer&rsquo；s disease, Huntington&rsquo；s disease (Huntington chorea), anxiety and substance-related disorders, especially substance use disorder, and substance tolerance conditions associated with substance withdrawal. Examples of a compound of general formula (I) are: 4-Pyridin-4-yl-2-(2-quinolin-2-yl-ethyl)-1,2-dihydro-pyrro[3,4-c]pyridin-3&ndash；one 4-Pyridazin-4-yl-2-(2-quinolin-2-yl-ethyl)-2,3-dihydro-isoindol-1-one 7-Pyridin-4-yl-2-(2-thieno[3,2-b ]pyridin-5-yl-ethyl)-2,3-dihydro-isoindol-1-one 7-(1-Methyl-1H-imidazol-2-yl)-2-(2-quinolin-2-yl-ethyl)-2,3-dihydro-isoindol-1-one
