A fitting system that may be used by a recipient to determine stimulation level parameters, such as threshold and/or maximum comfort levels, for a stimulating medical device is provided. These parameters may be for MAPs that may be used by a genetic algorithm in fitting a stimulating medical device. In obtaining these parameters, an internal component implanted in a recipient may apply stimulation to the recipient. In response, the recipient, using a user interface, may their information regarding their perception of the applied stimulation. This response may then be used to determine a stimulation level parameter that is then transmitted to the stimulation medical device for use in applying stimulation.