Most authorities (e.g., Myer & St. Louis, 2007; St. Louis, Myers, Bakker, & Raphael, 2007; Ward, 2006) suggest that cluttering is primarily a fluency disorder involving speech rate, or how fast a person speaks. When a person who clutters is speaking, his rate may be too fast, too irregular or "choppy," or possibly both, which makes it hard for the listener to understand what he is saying.

Various researchers (e.g., Myers, in press; St. Louis, Raphael, Myers, & Bakker, 2003; Teigland, 1996) also suggest that clutterers are unaware of their own speech problems and have trouble monitoring it as well. If rate is of utmost importance in a diagnosis of cluttering, and if most clutterers are not aware that they have a rate problem, it is possible that rate may be related to this unawareness of their speech. More specifically, maybe clutterers are unaware of the amount of time required to say something. Previous research regarding the related fluency disorder of stuttering has suggested that in general, people with fluency disorders have difficulty estimating the time of various events, such as the length of tones or how long a person has been speaking (e.g. Barasch, Guitar, McCauley, & Absher, 2000; Ezrati-Vinacour & Levin, 2001; Lass & Conn, 1974; Ringel & Minifie, 1966).

Lastly, Myers (1996) first suggested that clutterers are attempting to speak faster than they able, which may be related to a breakdown in their ability to monitor their own speech. This breakdown, together with an inability to estimate time in varying tasks, could yield symptoms of cluttering. If this were true, perhaps clutterers will also have difficulty estimating time, specifically the time required to say something. Clutterers may overestimate how long it will take them to say something, or they may underestimate.

To test this, six clutterers and six controls matched for age and sex participated in a study on time estimation. I (first author) asked them to estimate the amount of time required to say something and then to say the same thing out loud. To do this, participants used a laptop computer loaded with the Cluttering Assessment Program (CLASP) developed by Klaas Bakker (2005), which functions like a stop watch. I trained them in the following task sequence. First, I gave a prompt such as "Someone walking in front of you slips on the ice, what do you do?" or "Do you prefer cats or dogs, and why?" Following this prompt, participants thought about what they would say and then pressed and held the mouse button down for the exact time they thought they would need to say it. This gave me the "estimated time" of the participant's answer. The participant then released the mouse button, and immediately said the same answer aloud. He then evaluated if he said what he thought on a 1-5 scale. Timing the utterance gave me the "actual time," that is, how long it actually took the person to say the answer. Everyone completed 50 such questions with 4 or 5 accuracy ratings. I then compared the estimated time to the actual time to see if any differences existed. We first analyzed the results by comparing clutterers and controls as groups. The average estimated time of the clutterers (2.95 seconds [s]) was greater than the average estimated time of the control group (2.11s). This is a difference of nearly one second. Similarly, the average actual time for the clutterers (2.43s) was greater than the controls (1.93s), which is a difference of one half of a second. Finally, the averaged estimated-minus-average time was greater for clutterers (.52s) than controls (.18s). Although mean statistical differences did not differentiate cluttering and control groups, both groups overestimated time in general, and clutterers demonstrated a trend of overestimating more than controls.

Next, we analyzed individual clutterer-control pairs in the same manner. Individual cluttering-control pair differences revealed trends suggesting that two-thirds of each group (or 4 people from each group) overestimated speaking time, one-sixth (or 1 participant from each group) underestimated speaking time, and the remaining one-sixth (1 person from each group) estimated speaking time fairly accurately. The clutterers had more variability in their estimated times than controls, while variability in the groups' actual times were more similar. These results again suggest that clutterers were more variable than controls in all parts of the experiment, especially the estimation portion.

Although these differences in estimated time, actual time, and estimated minus actual times between clutterers and controls, as groups, were not statistically significant, the trends that emerged suggested that clutterers' perception of time was "off" in some manner. This is especially true when inspecting individual participant pairs. Many of those comparisons were significant; however the limited statistical power of six participants per group is most certainly a factor suggesting that we should be cautious about over-generalizing our results. Yet, if maintained with a larger sample, these trends would likely become statistically significant. The trends suggest that individuals who clutter have some disruption in their ability to estimate time. This may be caused by an internal time clock that is disrupted in some way, or due to an increase in time required to form an utterance.

While this study suggests that clutterers may have some differences with regard to their estimation of speech time, it is not clear at this time why these differences exist. Clutterers and controls, as groups, but not consistently so as individuals, both tended to overestimate their times. If this finding were to be replicated in future investigations, the implication to be drawn is that clutterers very likely do not talk fast because they cannot estimate their own speaking time. If controls had shown entirely different patterns than clutterers, then perhaps such a conclusion might be warranted. That, clearly, was not the case. Yet, time estimation is only one of many abilities or areas that could be included in measurement of awareness, meta-awareness, or speech monitoring. One possible explanation for cluttering symptoms may still be some inability to monitor one's own speech, as many of the treatment goals for clutterers involve heightening clutterers' awareness of their speech, and, many of these are successful.

References

Bakker, K., St. Louis, K. O., Myers, F. L., & Raphael, L. J. (2005). Computer aided assessment of cluttering severity. Paper presented at the 8th International Stuttering Awareness Day On-Line Conference. October, 2005. Retrieved July 1, 2009 from http://www.mnsu.edu/comdis/isad8/papers/bakker8/bakker8.html.

Barasch, C. T., Guitar, B., McCauley, R. J., & Absher, R. G. (2000). Disfluency and time perception. Journal of Speech, Language, and Hearing Research, 43, 1429-1439.

Ezrati-Vinacour, R. & Levin, I. (2001). Time estimation by adults who stutter. Journal of Speech, Language, and Hearing Research, 44, 144-155.

Lass, N. J. & Conn, W. H. (1974). Time perception: a comparative study of time estimations in empty passive, speech-filled passive, and speech-filled active conditions. Journal of Auditory Research, 14, 117-120.

Myers, F. L. (1996). Cluttering: A matter of perspective. Journal of Fluency Disorders, 21, 175- 185.

Myers, F. L. (In press). Treatment of cluttering: A cognitive-behavioral approach centered on rate control. In D. Ward & K. S. Scott (Eds.). Cluttering: Research, intervention, education. East Sussex, UK: Psychology Press.

Myers, F. L., & St. Louis, K. O. (2007). Cluttering. (DVD) Nashville, TN: The Stuttering Foundation.

Ringel, R. L. & Minifie, F. D. (1966). Protensity estimates of stutterers and nonstutterers. Journal of Speech and Hearing Research, 9, 289-296.

St. Louis, K. O., Myers, F. L., Bakker, K., & Raphael, L. J. (2007). Understanding and treating cluttering. In E. G. Conture & R. F. Curlee (Eds.), Stuttering and related disorders of fluency, (3rd ed.) (pp. 297-325). New York: Thieme.

St. Louis, K. O., Raphael, L. J., Myers, F. L., & Bakker, K. (2003, November). Cluttering updated. The Asha Leader, 8(21), 4-5, 20-23. Teigland, A. (1996). A study of pragmatic skills of clutterers and normal speakers. Journal of Fluency Disorders, 21, 201-214.

Ward, D. (2006). Stuttering and cluttering: Frameworks for understanding and treatment. East Sussex, UK: Psychology Press.

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