1. A medical device, comprising: a flexible tether adapted to be fed into a patient's throat, the flexible tether including a plurality of electrodes; a neural stimulation circuit adapted to deliver neural stimulation; and a controller adapted to control the neural stimulation circuit to provide an autonomic neural stimulation therapy using at least one electrode from the plurality of electrodes, the controller being adapted to implement a neural stimulation test routine, the neural stimulation test routine being adapted to assess neural stimulation efficacy for electrode subsets of the plurality of electrodes to identify a desired electrode subset for use in delivering the autonomic neural stimulation therapy to elicit a desired response.