One of the features with which the psychologist must constantly deal when investigating stuttering is the great amount of variation in the frequency of stuttering blocks or spasms. Steer 1 has shown that frequency of stuttering spasms is, at least to a certain degree, a function of the type of speech situation. Van Riper and Hull2 showed a progressive decrease in frequency of spasms as the stutterer adapted to any given speech situation. However, little knowledge was gained from these experiments as to what factors in the situations were responsible for the variations in frequency
