Perceptual and Motor Skills, 1976, 43, 27-30.
@ Percepmal and Motor Skills 1976
AGE, SEX, AND DELAY TIME AS FACTORS AFFECTING REACTION T O DELAYED AUDITORY FEEDBACK1 BEVERLY A. TIMMONS AND JAMES P. BOUDREAU University of Victoria Summary.-Five groups of 1 0 males and 1 0 females each, aged 5, 7, 9, 11, and 13 yr., recited a nursery rhyme under normal delay and 113-, 2 2 6 , 306-, 403-, and 520-msec delayed auditory-feedback conditions. Speaking rate and disfluenry count changes from normal delay to each delayed auditory feedback condition were calculared as indicators of reaction to delayed auditory feedback. Analyses of variance and post hoc comparisons indicated that 5-yc.olds reacted with greater change in rare at 520-msec. delayed auditory feedback than did older subjects. Five- and 7-yr.-olds were more disfluent at 413- and 520-msec. delayed auditory feedbadc than were older subjects. Sex differences were found in the 7-, 11-, and 13-yr.-old groups, using speaking rare as a measure of delayed auditory-feedback reaction. N o significant sex differences were noted when disfluencies were used as indicators of delayed auditory-feedback reaccion.
Under conditions of delayed auditory feedback, disruptions in speech are often noted (Lee, 1951; Black, 1951; Rawnsley & Harris, 1954; Fairbanks, 1955; Fairbanks & Guttman, 1958; Yates, 1963). Individuals vary in their reactions from no noticeable change in speech to almost complete incapacitation (Yates, 1963). The individual-differences variables related to differences in reaction to delayed auditory feedback have not been thoroughly investigated. The purpose of this study was to investigate age, sex, and delay time as possible factors influencing children's reaction. Few studies of the relationship between age and reaction have been done. Chase, et al. (1961) noted that, when using 200-msec. delayed feedback, subjects between the ages of 4 and G yr. were affected significantly less in rate change from normal to delayed auditory feedback as measured by words per second than those subjects in the age range of 7 to 9 yr. During normal delay, the younger subjects were slower and prolonged more words than did the older subjects. Percentages of words repeated, syllables repeated, and intrusions did not differ significantly for the two groups. MacKay (1968) and Buxton (1969) reported that younger children showed stronger reactions to delayed auditory feedback than did older children and that the delayed time to which maximum reaction was associated differed by age group. Using frequency of repetitions as a measure of reaction, MacKay (1968) demonstrated that subjects aged 4 to G yr. reacted maximally to conditions of 524 msec. Seven- to 9-yr.-olds showed most disruption to a delay of 375, while an adult group reacted maximally to a delay of 200 msec. Buxton (1969) found that subjects 'This research was supported by a grant from the Spencer Foundation, Chicago, Illinois.
28
B. A. TIMMONS
s: J.
P. BOUDREAU
aged 4 to 9 yr. showed the strongest reaction under 600-msec. delay. Ten- to 26-yr.-olds reacted with maximum disruption to 200 msec. Those 60 to 81 yr. of age were affected most by a delay time of 400 msec. Sex differences have been reported by King and Dodge (1965), Mahaffey and Stromsta ( 1965 ) , and Timmons ( 1971) . These experimenters used adults as subjects, leaving question about children's reaction. It is thought that, although there is some evidence of age and sex differences in reaction to delayed auditory feedback, variations in measurement of reaction, age groups, and delay times used make interpretations difficult. Since such feedback is used in therapy with stutterers (Van Riper, 1971; Ryan & Van Kirk, 1971), more information about factors affecting reaction seems necessary.
METHOD A stratified random sample was drawn from the Victoria, B. C . public schools. Five groups of 10 males and 10 females each, aged 5, 7, 9, 11, and 13 yr., constituted the sample. Each subject recited a nursery rhyme under conditions of normal and delayed auditory feedback. This task was chosen since many of the young subjects could not read but all could recite the rhyme. The speech of each subject was recorded under normal conditions and with delays of 113, 226, 306, 403, and 520 msec. Delay times were presented in random order. The apparatus used to record speech and to produce delayed feedback was a Korting Constellation 88 with a moveable playback head. A Korting 285 dynamic microphone picked up speech which was returned through a Sharpe 660 headset of 8 ohms nominal impedance. This apparatus was calibrated using a Tektronix 465 oscilloscope. The over-all band pass of the apparatus was 30 to 18K Hz. The feedback intensity was approximately 75 db above background noise, with slight variations produced by the subjects and limitations in the equipment. Two methods of obtaining measurement of reaction to delayed auditory feedback were used. Differences in speaking time between normal and delayed feedback conditions were calculated to the nearest 1/100 sec. Difference scores calculated from the number of disfluencies (omissions, substitutions, repetitions, and additions) under all conditions were also used. Two threeway analyses of variance with repeated measures were calculated, using difference scores for time and disfluency. I n an analysis of variance, using difference scores calculated from speaking times under normal and delayed feedback, significant differences were found in sensitivity of age groups to delays ( F = 53.9, df = 4/400, p .01). Reactions to delay times differed significantly ( F = 15.21, df = 4/360, p .01). A significant interaction between age and delay time was also noted ( F = 5.15, df = 16/360, p < .01). Post hoc comparisons, using the ScheffP
.01). These data indicate that the younger children were more affected by long delays than were the older children, supporting the findings of MacKay ( 1968) and Buxton (1969). It is thought that the variance in reaction to delayed auditory feedback may be due to age related differences in sensitivity to airconducted feedback and/or to fluency. When adult subjects were cold not co listen to their speech by Goldiamond, et al. (1962) less effect of delay was noted. It could be hypothesized that young children are more intent upon what they are trying to say than upon how their speech sounds ( in effect not listening to their speech). Under these conditions, only large discrepancies in feedback may be noticed. Lack of speech errors under normal delays may also be a factor. Atkinson (1954) reported that those adults with highly intelligible speech under normal conditions were less affected by delays than those with low intelligibility under normal conditions. If these findings are applicable to children, young children could be expected to show more reaction to delayed auditory feedback than older ones as a function of developmental faccors related to incelligibility.
@ Percepmal and Motor Skills 1976
AGE, SEX, AND DELAY TIME AS FACTORS AFFECTING REACTION T O DELAYED AUDITORY FEEDBACK1 BEVERLY A. TIMMONS AND JAMES P. BOUDREAU University of Victoria Summary.-Five groups of 1 0 males and 1 0 females each, aged 5, 7, 9, 11, and 13 yr., recited a nursery rhyme under normal delay and 113-, 2 2 6 , 306-, 403-, and 520-msec delayed auditory-feedback conditions. Speaking rate and disfluenry count changes from normal delay to each delayed auditory feedback condition were calculared as indicators of reaction to delayed auditory feedback. Analyses of variance and post hoc comparisons indicated that 5-yc.olds reacted with greater change in rare at 520-msec. delayed auditory feedback than did older subjects. Five- and 7-yr.-olds were more disfluent at 413- and 520-msec. delayed auditory feedbadc than were older subjects. Sex differences were found in the 7-, 11-, and 13-yr.-old groups, using speaking rare as a measure of delayed auditory-feedback reaction. N o significant sex differences were noted when disfluencies were used as indicators of delayed auditory-feedback reaccion.
Under conditions of delayed auditory feedback, disruptions in speech are often noted (Lee, 1951; Black, 1951; Rawnsley & Harris, 1954; Fairbanks, 1955; Fairbanks & Guttman, 1958; Yates, 1963). Individuals vary in their reactions from no noticeable change in speech to almost complete incapacitation (Yates, 1963). The individual-differences variables related to differences in reaction to delayed auditory feedback have not been thoroughly investigated. The purpose of this study was to investigate age, sex, and delay time as possible factors influencing children's reaction. Few studies of the relationship between age and reaction have been done. Chase, et al. (1961) noted that, when using 200-msec. delayed feedback, subjects between the ages of 4 and G yr. were affected significantly less in rate change from normal to delayed auditory feedback as measured by words per second than those subjects in the age range of 7 to 9 yr. During normal delay, the younger subjects were slower and prolonged more words than did the older subjects. Percentages of words repeated, syllables repeated, and intrusions did not differ significantly for the two groups. MacKay (1968) and Buxton (1969) reported that younger children showed stronger reactions to delayed auditory feedback than did older children and that the delayed time to which maximum reaction was associated differed by age group. Using frequency of repetitions as a measure of reaction, MacKay (1968) demonstrated that subjects aged 4 to G yr. reacted maximally to conditions of 524 msec. Seven- to 9-yr.-olds showed most disruption to a delay of 375, while an adult group reacted maximally to a delay of 200 msec. Buxton (1969) found that subjects 'This research was supported by a grant from the Spencer Foundation, Chicago, Illinois.
28
B. A. TIMMONS
s: J.
P. BOUDREAU
aged 4 to 9 yr. showed the strongest reaction under 600-msec. delay. Ten- to 26-yr.-olds reacted with maximum disruption to 200 msec. Those 60 to 81 yr. of age were affected most by a delay time of 400 msec. Sex differences have been reported by King and Dodge (1965), Mahaffey and Stromsta ( 1965 ) , and Timmons ( 1971) . These experimenters used adults as subjects, leaving question about children's reaction. It is thought that, although there is some evidence of age and sex differences in reaction to delayed auditory feedback, variations in measurement of reaction, age groups, and delay times used make interpretations difficult. Since such feedback is used in therapy with stutterers (Van Riper, 1971; Ryan & Van Kirk, 1971), more information about factors affecting reaction seems necessary.
METHOD A stratified random sample was drawn from the Victoria, B. C . public schools. Five groups of 10 males and 10 females each, aged 5, 7, 9, 11, and 13 yr., constituted the sample. Each subject recited a nursery rhyme under conditions of normal and delayed auditory feedback. This task was chosen since many of the young subjects could not read but all could recite the rhyme. The speech of each subject was recorded under normal conditions and with delays of 113, 226, 306, 403, and 520 msec. Delay times were presented in random order. The apparatus used to record speech and to produce delayed feedback was a Korting Constellation 88 with a moveable playback head. A Korting 285 dynamic microphone picked up speech which was returned through a Sharpe 660 headset of 8 ohms nominal impedance. This apparatus was calibrated using a Tektronix 465 oscilloscope. The over-all band pass of the apparatus was 30 to 18K Hz. The feedback intensity was approximately 75 db above background noise, with slight variations produced by the subjects and limitations in the equipment. Two methods of obtaining measurement of reaction to delayed auditory feedback were used. Differences in speaking time between normal and delayed feedback conditions were calculated to the nearest 1/100 sec. Difference scores calculated from the number of disfluencies (omissions, substitutions, repetitions, and additions) under all conditions were also used. Two threeway analyses of variance with repeated measures were calculated, using difference scores for time and disfluency. I n an analysis of variance, using difference scores calculated from speaking times under normal and delayed feedback, significant differences were found in sensitivity of age groups to delays ( F = 53.9, df = 4/400, p .01). Reactions to delay times differed significantly ( F = 15.21, df = 4/360, p .01). A significant interaction between age and delay time was also noted ( F = 5.15, df = 16/360, p < .01). Post hoc comparisons, using the ScheffP
.01). These data indicate that the younger children were more affected by long delays than were the older children, supporting the findings of MacKay ( 1968) and Buxton (1969). It is thought that the variance in reaction to delayed auditory feedback may be due to age related differences in sensitivity to airconducted feedback and/or to fluency. When adult subjects were cold not co listen to their speech by Goldiamond, et al. (1962) less effect of delay was noted. It could be hypothesized that young children are more intent upon what they are trying to say than upon how their speech sounds ( in effect not listening to their speech). Under these conditions, only large discrepancies in feedback may be noticed. Lack of speech errors under normal delays may also be a factor. Atkinson (1954) reported that those adults with highly intelligible speech under normal conditions were less affected by delays than those with low intelligibility under normal conditions. If these findings are applicable to children, young children could be expected to show more reaction to delayed auditory feedback than older ones as a function of developmental faccors related to incelligibility.
