Apparatus and method for assessing device function of a bilateral sensory system

An apparatus comprising:

• communication circuitry configured to receive first information from at least one first transducer and second information from at least one second transducer, the first information and the second information indicative of signals from an environment of a recipient or from the recipient's body;
• and
• evaluation circuitry configured to, during a first time period:
• receive a first portion of the first information indicative of a response of the at least one first transducer to the signals during the first time period;
• receive a first portion of the second information indicative of a response of the at least one second transducer to the signals during the first time period;
• and
• generate a first comparison of the first portion of the first information and the first portion of the second information;
• the evaluation circuitry further configured to, during a second time period subsequent to the first time period:
• receive a second portion of the first information indicative of a response of the at least one first transducer to the signals during the second time period;
• receive a second portion of the second information indicative of a response of the at least one second transducer to the signals during the second time period;
• generate a second comparison of the second portion of the first information and the second portion of the second information;
• and
• the evaluation circuitry further configured to generate a third comparison of the first comparison and the second comparison.

A method comprising:

• measuring and storing a first differential between responses of a first prosthesis and a second prosthesis to ambient excitations at a first time;
• measuring and storing at least one second differential between responses of the first prosthesis and the second prosthesis to ambient excitations at a second time subsequent to the first time;
• and
• detecting a performance degradation of one of the first and second prostheses, said detecting comprising comparing the at least one first differential to the second differential.