راهکارهای درمانی خاص در درمان لکنت زبان کلینیک تخصصی لکنت کرج کلاک نو- بلوار پاسداران- خیابان گلبرگ
162-230 SPM) for conversational speech of nonstuttering adult speakers, and these norma¬tive data have been universally accepted. This equates to a mean of 140 WPM with a standard deviation of 115-165 WPM. Reading rates have been found to be quicker, ranging between 210-265 SPM or 150-190 WPM (Darley & Spriestersbach, 1978). But here again we find potential sources of variability because, while this figure has been widely adopted, the methods and pro¬cedures that were used to arrive at this figure have varied substantially. One problem is how to incorporate natural pausing into the fluency count, and therefore how much time should be allowed for a pause before the rater stops the stopwatch, waiting for the speaker to begin again. Boberg and Kully (1985) suggest 3 seconds. But once again, there is no universally accepted norm for pause time into the syllable count and the potential discrepancies could be significant. For example, if two raters were both to calculate that a speech sample was spoken at exactly 200 SPM, during which time the speaker paused 4 times each minute, the difference between one rater waiting for 3 seconds and the other for 1 second would result in a 27 SPM discrepancy between the two calculations.
Articulatory rate and speaking rate
As we have seen from Figure 9.1, speaking rate refers to speech rate calcu¬lated from the total number of syllables spoken within a minute, whereas articulatory rate refers to the number of nonstuttered syllables spoken over the same time period. Figure 9.2 provides an illustration of how artifactual differences can appear in speech rate data, depending on the type of stutter¬ing that occurs within the speech sample. In this example, both speakers have six target syllables. But speaker A is repeating syllables whereas speaker B is prolonging them. Speakers A and B both complete the phrase in the same length of time, and both have the same number of disfluencies (speaker A has three instances of part-word repetitions, speaker B has three instances of phoneme prolongation). In terms of communicative content, then, both speakers A and B have stutters of similar severity. If we are looking to calcu¬late speaking rate though, speaker A will come out within the normal range, using the formula given in Figure 9.1 (thus 14 syllables/4 seconds x 60 = 210 SPM),