Patent US 4,020,567

A method and apparatus is utilized in the detection of certain characteristics in the speech of stutterers as they participate in a program which reconstructs the basic properties of speed sounds. The method of speech therapy for stutterers includes transducing a patient's speech into an electrical signal and comparing the transduced signal to a reference signal representative of the desired speech target behavior. The comparison is initiated when the amplitude of the transduced speech signal exceeds a threshold related to minimal sound level. When the amplitude of the transduced speech signal exceeds that of the reference signal, the subject is visually advised of an error in his speech. When the amplitude of the transduced speech signal remains above the trigger threshold and below the reference signal, the subject is visually advised that a correct speech response has been made. In a second embodiment, the rate of change of the amplitude of the subject's speech signal is compared with a reference related to the desired target behavior.