Abstract: One embodiment of an aspect of the present invention is a method for lessening the symptoms of depression, anxiety, and post-traumatic stress disorder comprising the step of administering a therapeutically effective quantity of a cholinergic M1 receptor antagonist and a therapeutically effective quantity of one or more cholinomimetic agents to lessen the symptoms of depression, anxiety, and post-traumatic stress disorder. Typically, the cholinergic M1 receptor antagonist is selected from the group consisting of telenzepine, amytriptyline, biperiden, trihexyphenidyl, darifenacin, dicyclomine, and tiotropium. Another aspect of the present invention is directed to methods and compositions employing other therapeutic agents and combinations of therapeutic agents for emulating the theoretical pharmacological effects of the non-selective mAChR antagonist scopolamine. The invention also encompasses pharmaceutical compositions incorporating one or more therapeutic agents and a pharmaceutically acceptable carrier.