disclosed are compounds of the formula or the pharmaceutically acceptable salts thereof wherein the variables r 5 , r 11 , r 12 , r 13 , r 1 , r 11 , ar , n , m and l are defined herein . these compounds are useful in treating various neuropsychochological disorders including , for example , schizophrenia , dementia , depression , anxiety , parkinson - like motor disorders and motion disorders related to the use of neuroleptic agents affective disorders such as schizophrenia and depression as well as certain movement disorders such as parkinsonism . furthermore , compounds of this invention may be useful in treating the extrapyramidyl side effects associated with the use of conventional neuroleptic agents . the interaction of 1 -) aminoisoindole derivatives of the invention with dopamine receptor subtypes is described . this interaction results in the pharmacological activities of these compounds .