control stimulation circuitry to deliver a first electrical stimulation pulse;

control sensing circuitry to detect, after delivery of the first electrical stimulation pulse, an ECAP signal;

determine a characteristic value of the ECAP signal elicited by the first electrical stimulation pulse;

determine an ECAP differential value that indicates whether the characteristic value of the ECAP signal elicited by the first electrical stimulation pulse is one of greater than a selected ECAP characteristic value or less than the selected ECAP characteristic value;

determine, according to the ECAP differential value, one of a decrement mode or an increment mode for determining a parameter value that at least partially defines a second electrical stimulation pulse;

determine, based on the determined one of the decrement mode or the increment mode, a gain value;

determine, according to the gain value and the determined one of the decrement mode or the increment mode, the parameter value that at least partially defines the second electrical stimulation pulse; and

control the stimulation circuitry to deliver the second electrical stimulation pulse according to the parameter value.