The postdoctoral fellowship research described in this document was based on three main areas: 1) single subject research, including experiments in learning with a rat and with three stutterers; 2) linguistic research, including basic research methodology and the analysis of morphological and syntactical structures in a language; and 3) neurophysiological research, including a review of current research and the analogous processes underlying both motor and perceptual systems. It is hoped that over the next few years this continuing research may lead to a significant breakthrough in the area of pathological stuttering. (MBM)