Journal of Personality and Social Psychology1996, Vol. 70, No. 3,451-460

Copyright 1996 by the American Psychological Association, Inc.0022-3514/96/S3.00

Anxiety, Alcohol, Aphasia, and Urns

Nicholas Christenfeld and Beth CreagerUniversity of California, San Diego

Although several studies have documented a link between anxiety and filled pauses (urns, ers, anduhs), numerous failures make it impossible to believe that the two are linked in any simple way. Thisarticle suggests anxiety may increase urns not when it makes the speech task harder but when itcauses the speaker to pay attention to the speech. Two experiments examined this idea. One manip-ulated evaluation apprehension, and the other manipulated self-consciousness. Both showed dra-matic increases in urns. Two more studies examined the real-world implications of this approach.Alcohol, which makes speaking harder but also makes speakers care less about what they say, wasfound to reduce urns. The second study found that Broca's aphasics, who produce simple speech butmust deliberate over every word, produce many urns. Wernicke's aphasics may not talk well, but donot mind, and manage with few urns.

Anxious speakers, almost everybody assumes, will litter theirspeech with urns and ers. It has been shown that undergraduatesbelieve nervous people produce more of these filled pauses(Christenfeld, 1995), and rhetoricians warn their pupils againstusing urns to avoid betraying anxiety (McBurney & Wrage,1953; Samovar & Mills, 1983). Unfortunately, the empiricalevidence does not support this simple intuition. Nor does it re-ject it. Of 16 reports examining the effect of anxiety on filledpauses, 5 found an increase (Boomer, 1963; Jurich & Poison,1985; Koomen & Dijkstra, 1975; Lalljee & Cook, 1973; Panek& Martin, 1959), 10 found no difference (Cook, 1969;Feldstein, 1962;Kasl&Mahl, 1965; Mahl, 1956,1987;Meisels,1967; Paivio, 1965; Pope, Blass, Siegman, & Raher, 1970; Sieg-man & Pope, 1965a, 1965b), and 1 found a decrease in urnswith greater anxiety (Blass & Siegman, 1975).

There are too many findings on each side of the issue to dis-miss the inconsistency as a statistical artifact. It is also unlikelythat the null findings were a product of ineffective anxiety ma-nipulations, because most of these studies found increases inother disfluencies, such as sentence restarts and silent pauses. Amore likely explanation is that the variability in the effect ofanxiety reflected some variability in the kind of anxiety createdin the studies. Rochester (1973), reviewing some of these stud-ies, suggested that the state-trait distinction might explain themixed results. Of the six studies examining trait anxiety, onefound a correlation between anxiety and um rates and fivefound no relationship. Thus, there is no compelling evidenceshowing that trait anxiety is linked with filled pause production.The story, however, is not so clear for state anxiety experiments.Of these, four found the predicted effect, seven found nothing,and one found the opposite relationship, with more anxiouspeople saying um less often.'

Nicholas Christenfeld and Beth Creager, Department of Psychology,University of California, San Diego.

Correspondence concerning this article should be addressed to Nich-olas Christenfeld, Department of Psychology 0109, University of Cali-fornia, San Diego, 9500 Gilman Drive, La Jolla, California 92093. Elec-tronic mail may be sent via the Internet to nchristenfeld@ucsd.edu.

Some further division of the experiments is necessary to un-derstand the mixed effects of manipulated anxiety on filledpause production. It is, however, very difficult to develop a betterway of categorizing these experiments because almost all ofthem manipulated anxiety by altering the topic of the speech.The anxious speech was produced when the participant talkedabout something like sex, and the calm speech was producedwhen he or she talked about something like school. Becausetopic has repeatedly been shown to have a profound effect onfilled pauses (Goldman-Eisler, 1968; Schachter, Christenfeld,Ravina, & Bilous, 1991), disentangling anxiety effects from theeffect of familiarity or expertise is probably impossible for suchstudies.

Explanations for the elusive filled pause-anxiety connectiontend to be based on the long-dominant notion that urns are asymptom of the breakdown of the speech production apparatus(cf. Goldman-Eisler, 1968). When the next word, phrase, oridea is especially hard to select and more time is needed, apause, either filled or silent, will occur. Thus, manipulationsthat change the demands of the speaking task should changethe rate of pauses. Mahl (1956), whose work on disfluencies inpsychiatric interviews started the flurry of activity on urns andanxiety, suggested that anxiety interferes with all complicatedongoing behavior. That is, talking is simply harder when one isanxious than when one is calm, and harder talking involvesmore urns. As Mahl (e.g., 1987) suggested, anxiety does in-crease just about every imaginable disfluency, but urns stub-bornly refuse to go along with the others. It may be that urns arenot a sign of a breakdown in the system or that anxiety doessomething other than distract the speaker. This article exploresthese two possibilities and presents a set of studies supporting anew approach to the filled pause-anxiety connection.

One alternative etiology of filled pauses has been proposed byLevelt (1989), who argued that filled pauses are produced whenthe speaker detects an error, or an impending error, and stops tocorrect it. This removes speech production from its normally

1 Two articles examined both state and trait anxiety, accounting forthe 16 articles adding up to 18 studies.

451

452 CHRISTENFELD AND CREAGER

automatic, unconscious mode and brings the process into therealm of conscious attention. Levelt suggested that urns are asymptom of this repair process. However, it may be that urnsare a more general phenomenon than this and indicate that thespeaker is interfering in some way with the fluid production oflanguage. That is, detecting an error is one thing that can makea speaker think about what she or he is saying, but there areother things that can have the same effect. Thus, anything thatincreases deliberate control over speech production should in-crease the frequency of urns. Although Levelt has suggested thatthe detection of an impending error will cause an um, what isbeing proposed here is that anything that makes a speaker stopthe automatic production of speech can lead to an um, whetheror not there is an error involved.

This account is similar to the account of "choking" underpressure proposed by Baumeister (1984). He argued that con-scious attention to skilled performance can disrupt that perfor-mance by removing it from a fluid automatic mode and makingthe actor think consciously about his or her actions. He showedthat asking people to think about what their hands are doingmakes them perform worse on a manual game, as does lettingthem know that they are being evaluated. We suggest that, inthe domain of language, deliberate attention to what is beingsaid will manifest itself in the filled pause rate.

Not all types of anxiety will increase a speaker's self-con-sciousness about speech, and so not all types of anxiety shouldincrease urns. For example, one might imagine that a speaker inthe waiting room before major surgery might care very littleabout what he or she is saying to fellow patients. On the otherhand, if she or he is asked about a resume exaggeration during ajob interview, then her or his attention to the verbal output maybe very high. This latter form is what Schlenker and Leary(1982) referred to as social anxiety. That is, thinking that othersare evaluating what you say will focus your attention also onwhat you say. If the extension of Levelt's interference withspeech idea is correct, then this latter form of anxiety shouldincrease urns, whereas the former would not.

It is hard to determine the relationship between the variousanxiety manipulations used in previous work and the kind ofself-consciousness proposed here as the cause of urns. There isno particular reason to think that trait anxiety should be asso-ciated with attention to the content of verbal output and, thus,no reason to think that scores on trait anxiety scales should sys-tematically be linked to filled pause rates. State anxiety manip-ulations may have made the task more challenging for partici-pants without making them worry more about exactly whatthey were saying. The increase in other disfluencies suggests thatdiscussing sensitive material was indeed harder for them, butthis is not the same as making them more self-conscious abouttheir verbal output.

This line of reasoning is compatible with much of the evi-dence that Mahl has accumulated in his extensive studies ofspeech disfluencies. Kasl and Mahl (1965) found, for example,that filled pauses are more frequent when one is talking over anintercom than when one is talking face to face with someone. Inhis 1987 book, Mahl suggested that this is because the individ-ual deprived of nonverbal feedback, may need to "deliberatemore carefully" (p. 213). Mahl suggested that it is the difficultyof the task that creates filled pauses, whereas we are arguing that

it is the deliberation itself that creates the MWS by interferingwith the more automatic production of speech. In his 1958work (cited in Mahl, 1987), Mahl examined the MinnesotaMultiphasic Personality Inventory profiles of his participantsproducing the highest number of filled pauses and found thatthey tended to endorse such statements as "I am unusually self-conscious." These findings are clearly not sufficient evidence forthe proposed account, but they do provide an intriguing hintthat people who think about what they say may say um.

More effective than speculating about the implications of pre-vious manipulations for the role of self-consciousness is testingthese ideas directly. Accordingly, the first experiment manipu-lated anxiety in such a way that anxious participants should beespecially concerned about the content of what they are saying.In other words, they should be self-conscious about theirspeech. The manipulation did not alter the topic of the commu-nication, but half of the participants believed that their speechwould be analyzed by judges and used as a measure of theirintelligence, whereas the other half believed that their speechwas of no particular importance. The um rates of these twogroups could then be compared to assess the effects of this par-ticular form of anxiety.

Experiment 1

Method

Thirty East Coast undergraduates participated in the experiment aspart of a requirement for an introductory psychology class. Sixteen ofthe students were women and 14 were men; the median age was 20 years.

A simple one-variable design was used, with students randomly as-signed to either the high anxiety condition or the low anxiety condition.The students arrived and were seated in a small room facing a desk onwhich was a small tape recorder. They were told that their task was tomake up a story based on a small cast of characters that the experi-menter would provide. They were informed that the story should be acouple of minutes long but that the length did not really matter, andthey were told that their story would be recorded. They were informedthat they should begin their story almost immediately after being giventhe cast so that the speech would be fully spontaneous.

The students in the low anxiety condition were informed that the ex-perimenter was trying to get some samples of speech to use in trainingpeople on grammatical coding. It was stressed that it did not reallymatter what their story was like and that this task was an almost irrele-vant part of the project, with the real tasks to follow. The experimenterexplained that because he was training the people in the coding of spon-taneous speech, he thought it would be a good idea if the trainees wereallowed to practice on samples of such speech. The experimenter ex-pressed the hope that the student would be good enough to provide justsuch a sample. Although the students probably experienced some anxi-ety simply from coming into the laboratory and having the speech re-corded, this condition was designed to reduce social anxiety as much aspossible to make the encounter something like chatting with a friend.

Students in the high anxiety condition, however, were told that thetask was a quite reliable measure of general creativity. It had been used,the experimenter elaborated, to predict which aspiring writers wouldhave their manuscripts accepted for publication by The New Yorker. Fur-thermore, they were informed, the procedure had been used on a groupof artists, mostly sculptors, whose work was appearing in SoHo galler-ies. Their score on the story creativity task was strongly related to thecritical success of their show. For good measure, the students were alsotold that the test was being extended to the identification of promising

ANXIETY AND UMS 453

composers and that it was even expected that a good scientist, who alsoneeds to be creative, should do well on the test.

The students were informed that their stories would be shown to threejudges who would score them on a variety of scales relevant to creativity(e.g., integration of creative elements) and that stories would be as-signed an overall creativity score. This aspect was left deliberately vagueso that it would not influence the nature of the stories that the studentscreated. A few students had questions about the procedure, but noneappeared to doubt the basic explanation.

All of the students agreed to create a story and signed a consent form.Because we wanted the stories in the two conditions to be basically sim-ilar, the students were given the characters about which their storyshould revolve (an old lady, a young boy, and a pair of sneakers). Oncethe full explanation had been given and the characters provided, thestudents were told they should begin. If they asked about thinking itthrough beforehand or showed any tendency to do so, they were toldthat it was important that they begin right away so that the story wouldbe fully spontaneous.

While the students told their story, the experimenter, sitting to oneside and pretending to be absorbed in the contemplation of a pencil,unobtrusively counted the occurrences of filled pauses. There was notime limit on the story, and the students could end it whenever theychose.

Results

After the experiment, the stories were timed, and the urnswere counted again from the tape by a second coder unaware ofexperimental condition. The reliability of these two counts wasmore than satisfactory (r = .99). The average story lasted al-most 2.5 min. There were no significant gender differences inthe stories, and all analyses were collapsed across this variable.The basic hypothesis could be examined simply by comparingthe mean um rates for the high and low anxiety groups. Theserates were significantly different, /(28) = 2.28, p < .05, with anaverage of 7.03 urns per minute in the high anxiety conditionand an average of 4.07 in the low anxiety condition. This and allof the following comparisons for experiment 1 are presented inTable 1. As predicted, the students high in social anxiety pro-duced more urns.

Although it is clear that the manipulation had the expectedeffect on filled pauses, it is still possible that the increase in MWSwas not a product of self-consciousness about the speech, rather,it could have been due to the manipulation changing the natureof the task. That is, rather than simply making the studentsmore likely to fill their pauses, it might have caused them tochoose harder words, or talk faster, in an effort to impress the

imagined judges. Although not all alternate explanations can beruled out, a few of them can be examined.

If the increase in urns was due to the students making theirtask harder when they thought they were being evaluated, thenone might expect that those in the high anxiety condition wouldhave told a longer story or used longer words. The stories of thehigh anxiety students averaged 2.8 min, and those of low anxietystudents lasted a mean of 2.1 min. This difference was not sig-nificant, /(28) = 1.47, ns. The average number of syllables perword in the two conditions was calculated from transcripts ofthe stories. In the high anxiety condition, the average word usedhad 1.29 syllables; the average length in the low anxiety condi-tion was 1.27. The difference did not even approach signifi-cance, f(28) = 0.68, ns. Apparently the students did not tryto impress the judges by creating longer stories or using longerwords.

Another possibility is that the students in the high anxietycondition used a greater variety of words. If their stories weremore varied and less repetitious, or if they tried to demonstratetheir masterful vocabularies, then they should have used a largernumber of different words. Picking their words from a largervocabulary would presumably have increased their cognitiveload and led to more MWS. This can be assessed through what isknown as the type-token ratio. This procedure measures howmany different words a speaker uses out of some standard num-ber of words uttered. People with a small vocabulary will tend torepeat the same words more often and, thus, use fewer differentwords per group of words spoken.

It is essential that the compared samples be of the same lengthfor type-token analyses, because the ratio decreases as speechlength increases. The length of the shortest story, 150 words,was used as the standard. Students in the high anxiety conditionused an average of 76.9 different words out of the first 150 wordsuttered, whereas the low anxiety students used 76.4. Again,these two means did not differ significantly, /(28) = 0.20, ns. Agreater working vocabulary cannot explain the different use offilled pauses in the two conditions.

A third possibility is that the students in the high anxiety con-dition spoke more rapidly than those in the low condition. Ifthis were the case, either because they wanted to squeeze morecreativity per minute into their stories or because the anxietysimply made them talk more rapidly, then the increase in umrate may have simply reflected the greater effort required inchoosing rapidly among options. To evaluate this, we calculatedthe average rate of words per minute over the duration of the

Table 1Linguistic Characteristics of the Stories of High and Low Anxiety Students: Experiment 1

Anxiety

HighLow

Urns perminute

M SD

7.03 4.264.07 2.66

No. ofminutes

M SD

2.81 1.212.10 1.42

Syllables perword

M SD

1.29 0.071.27 0.07

Type-tokenratio*

M SD

76.93 7.2476.36 8.17

Words perminute

M SD

156.28 33.55156.79 32.57

% silence

M

17.7419.35

SD

1A17.06

No. of silences

M

19.6722.00

SD

4.952.98

Note. Only urns per minute differed significantly between the two groups.•See text for details.

454 CHRISTENFELD AND CREAGER

story. Again, the two rates were remarkably similar, with meansof 156.3 words per minute in the high anxiety group and 156.8in the low anxiety group. The rates did not differ significantly,J(28) = 0.04, ns. The um difference cannot be accounted for byfaster talking.

If the effect of the manipulation was to make the speech taskharder rather than making the speakers more self-conscious,then one would expect disfluencies reflecting difficulty to in-crease. We examined three such disfluencies: silent pauses, sen-tence restarts, and repetitions. All three represent the kinds ofdisfluencies that have been shown to reliably increase in anxietystudies failing to find any effect on filled pauses.

Silent pauses were defined as any period of silence lasting atleast 300 ms. The percentage of time spent in silence was notdifferent for the two conditions, f(28) = 0.53, ns, nor was thenumber of silent pauses, /(28) = 1.58, ns. Sentence restartswere defined as any time the speaker started a new sentencewithout having finished the previous thought. From the tran-scripts, we calculated the frequency of these disfluencies. Therewas no difference in the frequency with which disfluencies oc-curred, J(28) = 0.72, ns. Repetitions included any time thespeaker repeated exactly the same word or phrase. Again, thehigh and low anxiety groups did not differ, t( 28) = 0.68, n s.

Discussion

Of course, countless explanations other than greater concernwith evaluation could account for the effect of the manipulationon filled pause rates. Students in the high anxiety conditionmight have spent more time wondering how well other studentstold their stories, devoted more effort to recalling their previoussuccesses and failures, or distracted themselves searching theroom for hidden judges. However, if the urns resulted from thissort of distraction making the speech task tougher, then onewould expect that other disfluencies would also have becomemore frequent, and they did not. Previous work on anxiety hasshown that when the topic is more challenging, urns are un-affected, whereas other disfluencies increase. This dissociationbetween the two types of disfluencies is a strong argument for adifferent causal mechanism. Many forms of anxiety, as pre-viously examined, may make the speech task harder (possiblyby distracting the speaker or making the topic less familiar) andso increase disfluencies such as sentence restarts. However, theparticular form of anxiety manipulated in this experiment mustwork in a different way. We have suggested that it increases thespeaker's attention to what he or she is saying and, thus, in-terferes with the normally automatic aspects of speaking.

We are suggesting that it was not social anxiety per se thatproduced the filled pauses. Rather, self-consciousness about thespeech, which was a result of the anxiety, produced the increasein urns. If this was the case, then a manipulation of self-con-sciousness without anxiety should produce the effect, whereasanxiety without self-consciousness should not. The second ex-periment tested this prediction. In addition, it included a ma-nipulation of task difficulty to rule out the possibility that socialanxiety increased filled pauses because it made the speech taskmore difficult.

Both the speech-irrelevant anxiety manipulation and thetask-difficulty manipulation can provide some discriminant va-

lidity evidence for the role of self-consciousness in filled pauseproduction. If the evaluation apprehension manipulation of Ex-periment 1 had its effect because it made the task harder, thenthe task difficulty manipulation of Experiment 2 should havethe same effect. If the effect was due to general anxiety ratherthan specific concern about what was being said, then the task-irrelevant anxiety manipulation of Experiment 2 should in-crease filled pauses as well. Questionnaires were also includedin Experiment 2 to determine whether the three manipulationshad their intended effects on self-consciousness, task-irrelevantanxiety, and task difficulty. Experiment 2 allowed an examina-tion of how specific the um increase is to self-consciousness, aswell as a replication of how specific the effect of self-conscious-ness is to increasing urns.

Experiment 2

Method

Eighty Southern California undergraduates participated in this ex-periment to satisfy a requirement for an introductory psychology class.Forty-four of the students were women and 36 were men; the medianage was 20 years.

Students were randomly assigned to one of four conditions: a controlcondition, a self-conscious condition, an irrelevant anxiety condition,or a difficult topic condition. They were introduced to the experimentaltask, gave their speech, and filled out a questionnaire.

The control students were seated at a desk in front of a small micro-phone. They were told that the point of the experiment was to examinehow context affected vowel sounds and that they would be asked to saya few word pairs and then talk for a few minutes. They were then givena list of word pairs to read (e.g., mad dog). After they had finishedreading the list, they were told that the experimenter also needed themjust to talk normally for a bit and that they should spend a few minutesdescribing what they would do on their ideal day. They were told todescribe what they would do from the time they woke to when they wentto sleep, assuming that money was no object. This topic was choseninstead of the make-up-a-story format of the previous experiment be-cause it seemed less intrinsically anxiety producing, and the situationwas designed to make the students as un-self-conscious as possible. Inan experiment, knowing they were being recorded, they probably couldnot be as relaxed as chatting on the phone with their best friend, but theyshould have focused little attention on exactly what they were saying.

When students in the self-conscious condition arrived, they were toldthat the point of the experiment was to examine the sounds and struc-ture of various parts of speech. They were seated at a desk with a largemicrophone and a pair of headphones. They were asked then to put theheadphones on and discuss for a few minutes what they would do if theycould do anything they wanted for a day. As they talked, they heard theirown amplified voice over the headphones. There was no delay in thisside tone, and the volume was set slightly louder than the amplified sidetone of a telephone receiver. The situation was designed to make thespeakers self-conscious and to keep their attention keenly focused onspeech production without making them generally anxious.

Students in the irrelevant anxiety condition were told that the experi-ment was designed to explore coordinated movements and that theywould be asked to talk about a given topic and to dance for a few minuteswhile being videotaped. They were told that they could dance any waythey wanted and that the experimenter and one other coder would watchthe tape and code interlimb coordination. They were told that moredetails would be provided after the speech task. The speech task wasexactly the same as that used for the control condition. The studentswere told that the speech task was being used for an analysis of the effect

ANXIETY AND UMS 455

of the context on vowel sounds, and they also read a few word pairslike mad dog. There was an inconspicuous microphone, there were noheadphones, and the students were asked to talk about what they woulddo during their ideal day. Many students had further questions aboutthe dancing part of the experiment, but they were told that everythingwould be explained later. This condition was designed to make the stu-dents anxious but not to increase attention to or concern about theirspeech.

The task-difficulty manipulation involved asking the students to de-scribe what they ought to do on their ideal day. That is, if they had a daywhen they could do anything, what did they think would be the bestthing they could do for society? In all other respects, this condition wasidentical to the control condition. This task was chosen because itshould have required more thought than the other tasks but should nothave had a major effect on anxiety or self-consciousness.

After giving the speech, each student filled out a brief questionnaireto assess the effectiveness of the manipulations. One question asked howself-conscious students had been while they talked. The next asked howanxious they were about the experiment, and the last asked how difficultthey had found the speech task. The students rated themselves on 5-point Likert-type scales ranging from not at all (1) to very (5). Thesethree questions were designed to assess the effectiveness and specificityof the three manipulations.

Results

Because the experiment was designed to allow a comparisonof each of three manipulations with a control group, the analy-ses were carried out in the same way. For each dependent vari-able, a one-way, four-group analysis of variance was calculated,and then three a priori contrasts were applied. The self-con-scious group, the anxious group, and the difficult task groupwere compared with the control group. This study sought, inaddition to the predicted effect of self-consciousness on filledpauses, evidence of discriminant validity, with null effects ofanxiety and difficulty on filled pauses and null effects of self-consciousness on other dependent variables. Therefore, adjust-ing the alpha level to a more conservative level (as with theBonferroni or Dunnett corrections) was inappropriate. Thiswould have made Type I errors less likely but Type II errorsmore likely. This reduction in power would have biased manyof the tests in favor of the prediction.2 .

The effectiveness of the self-consciousness manipulationcould be assessed by comparing the answers students gave to thefirst question. The means for this question, as well as the othertwo, are provided in Table 2. Comparisons revealed that theself-conscious group was higher in self-consciousness than thecontrol group, F( 1, 76) = 6.87, p < .05, but that the other twogroups were not, F( 1, 76) = 0.19, ns, for the anxious group,andF(l, 76) = 2.34, ns, for the difficult group.

The anxiety manipulation was also effective. The anxietygroup was significantly higher in anxiety than the control group,F(1,76) = 13.93, p< .0005, whereas the other two groups werenot, F( 1,76) = 2.29, ns, for the self-conscious group, and F( 1,76) = 0.01, n s, for the difficult group.

The self-consciousness and anxiety manipulations appear tohave created the desired state only in the desired groups, but theresults from the question about how difficult students found thespeech task are not quite as clear cut. The difficult group wasmarginally higher than the control group on this measure, F( 1,76) = 3.82, p = .06. The self-conscious group did not differ,

Table 2Self-Report Manipulation Checks: Experiment 2

Group

ControlSelf-consciousAnxiousDifficult

Self-consciousnessquestion

2.353.55**2.553.05

Anxietyquestion

2.753.504.60***2.80

Difficultyquestion

2.552.651.85*3.45*

Note. Ratings were made on a scale ranging from 1 (not at alt) to 5(very). Experimental groups were compared with the control group foreach question.*p<A0. **p<.05. **•/;< .001.

F(\, 76) = 0.05, ns, but the anxious group was slightly, al-though nonsignificantly, lower than the control group, JF( 1,76)= 2.31, p - . 13. Those in the anxious group may have reportedthat the speech was not very difficult because they were com-paring it with the upcoming dancing task. Overall, the experi-ment should have been able to test fairly precisely the specificeffects of self-consciousness, anxiety, and task difficulty on filledpause production and other speech disfluencies.

The students took about 2 min to describe the fantasy dayand generally mentioned activities such as European travel withfriends or romantic candle-lit dinners. The self-conscious stu-dents' descriptions also included significantly more filled pausesthan their control counterparts produced. The self-consciousspeakers had a rate of 5.61 urns per minute, whereas the controlstudents used only 3.46 per minute, F( 1, 76) = 6.60, p < .05.The means for filled pause rate, along with other measures ofthe nature of the speech for the four conditions, are presentedin Table 3. Also shown in Table 3 are the significance levels ofthe contrasts comparing the three experimental groups with thecontrol group for each measure.

As in the first study, the speech produced could be comparedalong a number of dimensions in addition to filled pause rate.The self-conscious students' descriptions did not differ fromthose of the control group on any other measure calculatedfrom transcripts of the speeches. There were no differences inlength of description, number of syllables per word, vocabularydiversity,3 speech rate, rate of sentence restarts, or word repeti-tions. The effect of the self-consciousness manipulation wasconfined to the rate of filled pauses; there was no evidence thatthe self-conscious students made their speech any more com-plex or that these self-conscious speakers were any more likelyto utter other disfluencies. This finding replicates the results ofthe previous experiment on the specificity of the effect of self-consciousness. The other two experimental conditions testedthe specificity with which these results were due to self-con-sciousness rather than anxiety or task difficulty.

2 Even with Dunnett or Bonferroni corrections to reduce the proba-bility of Type I errors (but increase the chances of Type II errors), eachof the analyses described subsequently that was significant remainedsignificant.

3 For this experiment, the shortest speech was 73 words long, thus,the numbers were calculated out of the first 73 words of each person'sspeech.

456 CHRISTENFELD AND CREAGER

Table 3Linguistic Characteristics of Ideal Day Descriptions for Each Group: Experiment 2

Group

ControlSelf-consciousAnxiousDifficult

Urns perminute

M

3.465.61**2.07*3.85

SD

2.943.591.601.99

No. ofminutes

M

1.911.692.052.19

SD

1.441.201.031.13

Syllables perword

M SD

1.26 0.071.29 0.081.28 0.061.32** 0.07

Type-tokenratio'

M

56.0055.5056.6560.15*

SD

7.366.007.486.00

Words perminute

M

132.43130.91131.50128.33

SD

17.8626.1418.5413.92

Restarts per100 words

M

0.430.470.88*0.69

SD

0.620.740.860.87

Repetitionsper 100 words

M

0.430.261.24*0.62

SD

0.850.451.691.03

Note. Experimental groups were compared with the control group for each question.•See text for details.•p<.10. **p<.05.

The anxious students actually used marginally fewer filledpauses than the control students, F( 1,76) = 2.74, p = . 10. Theydid not differ in terms of length of speech, syllables per word,vocabulary diversity, or speech rate, but anxious students hadmarginally more sentence restarts and repetitions than controlstudents. Both of these disfluencies are ones that Mahl (1987)and others found to increase reliably with anxiety, and this alsoreplicates Mahl's findings of a dissociation between filled pausesand other disfluencies.4

The students in the difficult task condition did not differ sig-nificantly from control students in filled pause use, F( 1, 76) =0.22, ns, or in length of speech, speech rate, restarts, or repeti-tions. They did, however, use longer words and a marginallylarger vocabulary. Students in this condition, who describedwhat they ought to do during an ideal day rather than what theywould actually do, were more likely to use long words such asbenefactor and Samaritan and less likely to reel off a repetitivelist (e.g., "I would wake up, and then I would eat breakfast, andthen I would walk on the beach, and then I would.. . ."). Thesedifferences in vocabulary size and word length were slight butwere consistent with the self-reports of this being a more diffi-cult task. One might also expect that these students should havetalked more slowly, however, although the difference was in thisdirection (they used four fewer words per minute than controlstudents), it was far from significant. In spite of the difficulty ofthe task, these students were able to talk about as quickly anduse as few urns as students with the easier task.

Discussion

This experiment provides two sorts of evidence that filledpauses are produced when a speaker is self-conscious aboutspeech. One line of evidence is the replication of the first exper-iment, indicating that filled pauses are more frequent when par-ticipants are more self-conscious but that other disfluencies arenot affected. The other line of evidence is that this pattern isquite different from those found when the students were anxiousabout other matters or were producing more difficult speech. Inneither of these cases were filled pauses increased, althoughother disfluencies were affected. Explanations that urns are afunction of the challenge of the speech task or that they are aproduct of a generally disruptive effect of anxiety on highermental functions cannot predict these results.

The anxious students' filled pause rate suggests, albeit tenta-tively, that anxiety by itself not only will not increase urns butmay actually reduce them. The manipulation (expecting todance alone while being videotaped) may have distracted thestudents from what they were saying by focusing their attentionon the upcoming ordeal. In the introduction, we suggested thata patient waiting for major surgery should say um no more thannormal, but this finding suggests that when the topic is unre-lated to the source of the anxiety, the patient may say um lessoften than normal. Of course, such a prediction is tempered bythe finding that the anxious students did not report especiallylow self-consciousness, and the effect on their filled pauses wasonly marginally significant.

The manipulations used in Experiments 1 and 2 were some-what artificial laboratory constructions designed to maximizethe chances of obtaining an effect. Speakers rarely hear theirown amplified voices or have their speech rated by judges forcreativity. If the proposed account of filled pauses is correct,however, it ought to be possible to find naturally occurring ex-amples of self-consciousness producing filled pauses. We con-clude this article with two nonexperimental observations offilled pause production in bars and in aphasics.

Drinking alcohol interferes with just about every task thatintoxicated people attempt. Fairly low levels decrease bothspeed and accuracy in reaction time tasks (Maylor, Rabbitt,James, & Kerr, 1992). Alcohol, again in small doses, impairslearning and memory for nouns (Jones & Jones, 1977). Abouthalf of car fatalities involve an intoxicated driver (Centers forDisease Control, 1982).

Alcohol, however, has more subtle effects than simply im-paired performance. There is a considerable body of evidencesuggesting that alcohol reliably decreases people's self-aware-ness (cf. Hull, Levenson, Young, & Sher, 1983; Zeichner & Pihl,1979). Steele and Josephs's (1990) approach to intoxicationsuggests a mechanism for this decrease in self-consciousness.They demonstrated that alcohol decreases people's ability to at-tend to more than one thing at a time. Thus, it should be hardfor drinkers to produce speech and also attend to what they aresaying.

4 The other disfluencies that Mahl (1987) included in his speech dis-turbance index, such as tongue slips and incoherent sounds, were soinfrequent that they did not allow for meaningful analyses.

ANXIETY AND UMS 457

Drunk talkers thus should be more likely to run into troublebut also should be less concerned about it. They should have aharder time formulating their speech, remembering the wordsthey need, keeping the grammar on track, and so on. However,they should be less likely to detect impending or existing errorsand should care less whether these errors occur. Sober individu-als, on the other hand, will be much better at the technical as-pects of speech production but will be far more likely to monitorwhat they are saying and consciously redirect it when it goesastray.

One advantage of examining alcohol's effects is that the chal-lenges of the speech task and the level of self-consciousness areoppositely affected. If the actual challenge of speech productionproduces urns, then intoxicated individuals should use thesefillers more often. However, if urns are produced not by toughoptions but by self-consciousness about what is being said or bythe removal of speech production from its automatic mode,then these individuals should manage with few urns.

Experiment 3

Method

One hundred eight people were interviewed in bars in the San Diegoarea. The experimenter went to eight local bars on 13 different nights.The bars were distributed within easy reach of a college campus, andthey were popular with students and recent graduates. The experi-menter randomly picked patrons, told them she was doing a project fora class, and asked whether they would be willing to answer a few ques-tions. When they agreed, and all approached did agree, she asked themthe same question participants in Experiment 2 had answered (i.e.,What would they do if they could do anything they wanted for a day?).The experimenter noted on a clipboard how many urns they used andhow long they spoke. For 40 of the interviews, a second experimenterstood off to one side and also counted the number of filled pauses pro-duced. Both coders were unaware of the patrons' state of intoxicationduring the counting of urns.

When they had explained their ideal day, the experimenter askedthem how many drinks they had consumed so far that evening and alsoasked them their weight. A few patrons resisted divulging their weight;for these individuals, the experimenter noted an approximate weight.The weight was recorded so that a rough conversion of number of drinksto blood alcohol concentrations (BAC) could be made.

For 42 of the interviews, the experimenter also made a note, on arough 4-point scale, of the social appropriateness of the patron's daylongfantasy description. A score of 4 indicated a response that could bemade in the presence of one's grandparents. A score of 3 indicated aresponse that could be made in the presence of a group of friends, and ascore of 2 indicated a response that could be made only to a very closefriend. Finally, a score of 1 indicated a response representing the type offantasy that should not be described in public, although, of course, allof these stories were confided to a perfect stranger in a bar. This codingwas designed to examine the link between alcohol and monitoring ofwhat one says.

Results

The average bar patron had consumed three drinks by thetime he or she was approached by the experimenter; 11 had notconsumed any alcohol at all. The time sequence of the drinks,recency of food intake, and a number of other factors shouldinfluence actual BAC, but these factors should simply add noise

to the measure rather than systematic error. People who hadconsumed a greater number of drinks had probably done soover a longer period than those who had finished only a few, andthus they would have metabolized more of the alcohol. How-ever, if one assumes a fairly steady intake and metabolizing rate,then the number of drinks measure should overestimate the ac-tual blood alcohol by a constant percentage but still be a fairlygood indication of relative intoxication.

The reliability of the urn scoring was assessed by comparingthe counts of the two experimenters for the 40 interviews inwhich both were present. This produced a reliability (r) of .97.Urns are apparently as easy to count in bars as they are inlaboratories.

Number of drinks and um rates were significantly associated.The more intoxicated the speaker, the rarer the urns. The effectwas not huge but was significant (r = -.20, p < .05). The effectwas not changed by eliminating the one very intoxicated outlier(r = -.20) or by using a measure of BAC that took body weightinto account (r = -.22). The roughness of the measure of in-toxication and the heterogeneity of the sample no doubt atten-uated this relationship. The effect size was smaller than thoseof Experiment 1 (t; = .40) and Experiment 2 (n = .32 for thecomparison between the self-conscious group and the controlgroup).

Before suggesting intoxication as a strategy to concerned pub-lic speakers, it should be noted that, to eliminate the averagespeaker's urns, about 19 drinks in the course of an evening arerequired (assuming a linear alcohol-wm relationship).

The social acceptability of the fantasies was related to thenumber of drinks that their inventors had consumed (r = — .39,p < .05). This supports the notion that the alcohol made thespeakers less concerned with what they were saying and lessprone to monitor it, at least for social acceptability. There wasno significant association between social acceptability score andum rate (/• = -.08, ns). Given the roughness of this measure ofspeech monitoring, the small number of individuals availablefor this comparison, and the already weak association of urnswith BAC, this insignificance is not surprising, although theproposed account does suggest that it should exist.

Discussion

Experiment 3 showed a link between drinking alcohol andavoiding urns. The more intoxicated patrons, in spite of pre-sumably greater trouble with all aspects of producing speech,used fewer urns. This suggests that, in line with the first twoexperiments, task concern, rather than task difficulty, createdthese fillers.

This study cannot distinguish between decreased filledpauses being a result of the actual alcohol consumed or alcoholexpectancy effects. These two were confounded, as they are gen-erally in bars and most places people drink outside psychologylabs. Steele and Josephs (1990) suggested that the inability toattend to more than one thing at a time is due to actual alcoholconsumption; for the present purposes, however, it did notmatter. The people who reported drinking more were the peoplewho produced less socially acceptable speeches. Whether theydid not monitor what they said because they were drunk or be-cause they thought they were drunk does not matter. Either way,

458 CHRISTENFELD AND CREAGER

the theory predicts that filled pauses should be reduced, andthey were.

Because the data were collected in a field study rather than alaboratory experiment (it being better both ethically and fi-nancially to let participants buy their own drinks), the causalitycannot be proved. It is at least conceivable that the kind of peo-ple who drink excessively are the same ones who do not say umoften. There are several factors that make such an explanationunlikely, however. First, our measure of intoxication was a poormeasure of the personality disposition to drink. All of the pa-trons had chosen to go to bars and had been there at roughly thesame time in the evening, so the range of drinkers was greatlycompressed. Furthermore, because we measured how muchthey had consumed at a random point in the evening ratherthan how much they would consume in the entire outing, ourmeasure was biased by such important factors as how recentlythey had arrived and how rapidly they drink. It is very unlikelythat such a poor measure of a personality trait to drink would becorrelated, even weakly, with a single measure of the personalitytrait to say um infrequently (see Mischel, 1968, for an extensivediscussion of the difficulty of predicting a single behavior re-flecting one trait from another single behavioral measure of thattrait, let alone a single measure of a different trait). Rather thanquibble about causality, however, we note simply that the ap-proach made a nonobvious prediction about a naturalistic be-havior, and that prediction was confirmed.

One final prediction of this idea that urns reflect deliberatecontrol over speech production, rather than the challenges thatthe system is facing, is examined here. People suffering damageto the left hemisphere can display a variety of language deficits.Although there is tremendous overlap and variability in thesedisorders, they do form rough groups (Kolb & Whishaw, 1990).One disorder, Broca's aphasia, is characterized by greatly sim-plified speech composed of only the infinitive form of verbs andsingular nouns, with few adjectives, adverbs, and other frills.This speech, in spite of being reduced to such a simple form, isslow and deliberate. These speakers are aware of their troublearticulating their meaning, and they make a conscious effort toform the speech. The speech of Wernicke's aphasics is quitedifferent. Their speech can involve a great variety of words andforms but will make little sense, often being meaningless "wordsalad." It is neither slow nor deliberate. They do not realize thatthey are not communicating effectively and do not, or cannot,exert conscious control over this flow of speech.

Wernicke's aphasics, then, should fall into the same group asthose who are intoxicated. They may not be producing speechvery well, but they are not concerned about it, and so theyshould use few urns. Broca's aphasics are more like sober indi-viduals. Their speech is better at conveying information; how-ever, because they deliberate over it, urns will be produced. Thespeech of Broca's patients should be especially high in urns, be-cause they have to work on every word they utter and are inca-pable of letting their speech production apparatus run automat-ically. Whitaker (1976, 1983) has proposed a similar accountof aphasia as being a disorder of either the automatic or thecontrolled aspects of speech production. He has argued thataphasias can be used to localize automaticity in the brain; forthe present purposes, however, it is enough that aphasias seemto selectively affect either the controlled or the automatic as-

pects of speech. Several people have considered the pauses ofaphasics but have not compared the um rates of the two basiccategories of aphasia (cf. Howes & Geschwind, n.d.; Quinting,1971).

To test these ideas about the urns of aphasics, we coded thespeech of both types of patients in terms of um rates. Previouslyrecorded speech samples of aphasics were provided by DavidSwinney (who recorded aphasics at the New "York Veterans Ad-ministration Hospital in 1991) and Tracy Love (who recordedaphasics at the Aphasia Research Center, Boston, in 1993). The8 Broca's and 5 Wernicke's aphasics had been asked to say any-thing they wanted about a picture they were shown (the "cookietheft" from Goodglass & Kaplan, 1972) and were allowed totalk without much prompting from the interviewer. The num-ber of filled pauses and the duration of the descriptions werecoded from the tapes.

The Wernicke's aphasics produced 0.9 filled pauses per min-ute, whereas the Broca's aphasics produced 6.7, a significantlygreater rate, t{ 11) = 3.12, p < .01. Because of the very differentspeech rates of the two sorts of patients, filled pauses per hun-dred words rather than filled pauses per minute may be a betterindication of the tendency to say um. To compute this rate, wetranscribed the descriptions and counted the total number ofwords. For every hundred words uttered, the Wernicke's apha-sics produced, on average, 1.2 urns, and the Broca's aphasicsproduced 25.4. The difference in this filled pause rate was alsosignificant, /(11) = 3.08, p < .05. By way of comparison, theaverage undergraduate in Experiment 1 uttered 3.5 urns perhundred words. Overall, the data suggest that Wernicke's apha-sics use few urns, but the majority of the difference was due toa very high rate for Broca's patients. (The effect size for bothdependent variables was .68; the difference between these twogroups had a more profound effect than the manipulations ofthe previous experiments.)

It is, of course, possible to explain the high um rate of theBroca's aphasic without mention of the deliberate control overthe once automatic process of speech production. But what isclear is that the complexity of verbal output is not always a goodindicator of the frequency of filled pauses, because the morecomplex and varied speech of Wernicke's aphasics involves fewurns and the enormously simplified speech of Broca's aphasicsinvolves many.

General Discussion

In general, the cause of urns proposed here moves away fromthe cognitive complexity notions that have long been in favor.Anxiety, it is suggested, does not itself play a causal role in filledpause production. However, anxiety is sometimes accompaniedby increased attention to the content of one's own speech, andthis self-consciousness about the speech, whether or not it is aproduct of anxiety, will lead to more filled pauses. Alcohol willdo just the opposite, keeping speakers talking without muchmonitoring of what they are saying. The aphasias differ in theattention that their victims must devote to controlling what theysay, and the um rates reflect this.

The proposed account of urns described here requires thatspeaking be accomplished quite successfully without deliberateinterference or control. As Levelt (1989) pointed out, it is for-

ANXIETY AND UMS 459

tunate that people are capable of just this sort of automatic pro-duction of speech. If we had to think about what word to say asmuch as we think about what tie to wear, speech would be halt-ing indeed. People do occasionally interfere with their ownspeech, and urns may signal when such executive control is ex-erted over the normally automatic process. Generally, auto-matic processing is diagnosed by such symptoms as its imper-viousness to the addition of other tasks (e.g., memory load;Schneider & Shim-in, 1977). Filled pauses may, in a similar way,provide information about moments when speech is not beingproduced automatically. That is, rather than indicating when atough decision is being made by the normal speech productionapparatus, urns may indicate when the speaker changes modesand gives deliberate attention to some aspect of the speech. Thissignal could prove useful in tracking the development of auto-matic speech in children and nonnative speakers.

It is probably the case that the difficulty of the speech taskand the um rate are not entirely independent, because attentionto what one says is likely to be high when the task is hard. How-ever, it does seem to be the case that one can predict far betterwhat the rate of filled pauses will be from an examination of thesocial context of the utterance than from an inspection of thecomplexity of the output. The mechanism by which these socialfactors influence urns differs from that traditionally assumed.These factors do not operate by simply adding to the existingcognitive load; rather, they change the way in which the speechis generated.

This approach to filled pauses suggests that they should beaffected by a number of social variables that do not necessarilyhave any effect on the actual verbal output. For example, thenature of the audience should have a profound effect on the umrate of the speaker. It is readily observable that messages left onanswering machines are overflowing with ums that do not occurwhen someone actually answers the call. Knowing that one'swords are being recorded makes this unnatural form of com-munication especially likely to focus attention on what is beingsaid. Telling a story to one's best friend may lead to fewer filledpauses than telling the same story to a parole officer. This ap-proach also suggests that people who make an effort to speakwell may use urns more often than people who do not care howwell they are talking. In fact, the best way to eliminate urns fromone's speech—better than tranquilizers or alcohol—may be toramble, saying whatever pops into one's head without any con-cern for whether it is appropriate, informative, or interesting.

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Received April 13, 1994Revision received September 15, 1995

Accepted September 28, 1995 •