Systems and methods for patient interactive neural stimulation and/or chemical substance delivery are disclosed. A method in accordance with one embodiment of the invention includes affecting a target neural population of the patient by providing to the patient at least one of an electromagnetic signal and a chemical substance. The method can further include detecting at least one characteristic of the patient, with the characteristic at least correlated with the patient's performance of an adjunctive therapy task that is performed in association with affecting the target neural population. The method can still further include controlling at least one parameter in accordance with which the target neural population is affected, based at least in part on the detected characteristic.