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Childrens perception of their phonologically modified speechSofia StrmbergssonKTH Speech, Music and Hearing more particularly, children with deviant speech, whose recorded speech is automatically corrected and played back to them.1

Dive me the tube.No, not the tube! The tube![tu:b]

The tube?Phonological impairment (PI)2012-09-11Interspeech 2012, Portland#2Introduce the problem with the following scenario:A child (normal intelligence, physiology etc., but with deviant speech)An adult, who has two objects: a cube and a tube

But what can we tell about the child from this scenario?

Phonological impairment (PI)2012-09-11Interspeech 2012, Portland#3The child can distinguish between tube and cube in the adults speech.A) When he tries to produce the word cube, it comes out as tube, B) He doesnt perceive that it came out wrong. He perceives what he intended to say...

But what if he heard his own recorded speech would he then perceive it as right or wrong? This leads us to the research questionsHow do children with and without PI perceive their own recorded (original and modified) speech?

For the children with PI, how does this compare to their online judgment of their deviant speech?

2012-09-11Interspeech 2012, Portland#Do the children perceive the played back speech as correct or incorrect?Do they notice the modification?4Participants12 children with PI

4-7 ys

Language comprehension OK

/k, g, / -> [t, d, n]20 children w/ typical speech

4-7 ys

Language comprehension OK2012-09-11Interspeech 2012, Portland#Two 20-minute test sessions, a range of speech perception tasks. 5

([k] replaced by [k], still correct)([t] replaced by [k], to deviant)(deviant /k/ replaced by [k], corrected)(deviant /t/ replaced by [t], corrected)

2012-09-11Interspeech 2012, Portland#Child says what he sees on a picture, the speech is recordedThe speech is modified (possibly corrected)Speech sample is played backAim: Change the phonological form without affecting the perceived speaker identity.6External identificationModified speech I (Parrot): correct/incorrect?Modified speech II (Parrot): correct/incorrect?Modified speech III (Monkey): me/modified?PI: Own speech (online): correct/incorrect?PI: Own speech (recd): correct/incorrect?

2012-09-11Interspeech 2012, Portland#SPEED!Here, the children were presented with original and modified recordings of other children. The task: judge the phonological accuracy of each stimulus, by pointing either to a picture illustrating the stimulus word, or to the X when they perceived the word as wrong. 7External identificationModified speech I (Parrot): correct/incorrect?Modified speech II (Parrot): correct/incorrect?Modified speech III (Monkey): me/modified?PI: Own speech (online): correct/incorrect?PI: Own speech (recd): correct/incorrect?

2012-09-11Interspeech 2012, Portland#SPEED!Here, the recording was either modified (toCorrect or toImpaired) or left unchanged.

Instruction: The Parrot will imitate what you just said, but The Parrot doesnt always get it right.

This task was performed I) immediately after having produced the word, and II) after an intervening non-related task.8External identificationModified speech I (Parrot): correct/incorrect?Modified speech II (Parrot): correct/incorrect?Modified speech III (Monkey): me/modified?PI: Own speech (online): correct/incorrect?PI: Own speech (recd): correct/incorrect?

2012-09-11Interspeech 2012, Portland#SPEED!Just as in the Parrot tasks, the recording was either modified (toCorrect or toImpaired) or left unchanged. Instruction: The Imitation Monkey (Hrmapan) will imitate what you said, but only occasionally. Point to the child if you think that the recording sound exactly as you said it, or to The Imitation Monkey if you think it sounds any different from what you said.9External identificationModified speech I (Parrot): correct/incorrect?Modified speech II (Parrot): correct/incorrect?Modified speech III (Monkey): me/modified?PI: Own speech (online): correct/incorrect?PI: Own speech (recd): correct/incorrect?

2012-09-11Interspeech 2012, Portland#SPEED!Only children with PI.Instruction: Say what you see on the picture, and then say if it came out right or wrong. Speech was recorded and played back to them later, when they were asked again to judge if what they heard was right or wrong. Thus, we collected both the childrens online evaluation, and their delayed evaluation of the recorded speech.10

PI < nPIF(1,30) = 9.65, p = .004Online < Recdt(143) = -3.64, p < .0012012-09-11Interspeech 2012, Portland#ExtIdent: Both groups perform on the same high level.Parrot I & II: the nPI group perform as in the ExtIdent-task. However, the PI group doesnt reach the same level significant difference. No diff. direct vs. delayed.Monkey: Drastically lower level of performance - for both groups of children, its more difficult to detect when modification has taken place (Monkey), than to judge phonological accuracy (ExtIdent + Parrot). No diff. between the groups.IntIdent I & II: Significant diff. between the online condition and the recorded/delayed condition judging recorded speech is easier than judging online speech. 11Worse performance on modified stimuli?YESYESPerformance dependent on accuracy?YESHard to detect modification when phonological form is unchanged.2012-09-11Interspeech 2012, Portland#Are the childrens performance affected by the nature of the stimuli?1) Modified stimuli judged more poorly than original stimuli, but only in ParrotII and in the Monkey task. Effect of bad synthesis quality? But then, why dont we find the same effect in ParrotI?2) Easier to hear the modification (i.e. point to the Monkey) in stimuli that have been impaired by the synthesis.So, the children often mistake modified stimuli where the phonology is not changed as having been produced by themselves.Good results as an evaluation of the synthesis quality the children only perceive modification when phonological form is changed.12Conclusions

External perception is not the problem

Use recordings original and/or modified to approach the real challenge:self-monitoring2012-09-11Interspeech 2012, Portland#To wrap up, I will return to the child I presented in the beginningDont waste time on practicing external perception in phonological therapy!Instead, we encourage the use of recordings!13Thank you for your attention!2012-09-11Interspeech 2012, Portland#