Dept. for Speech, Music and Hearing

Quarterly Progress andStatus Report

Compensation orundershoot: Effect ofspeaking rate on jaw

movements during theproduction of Finnish

diphthongsHurme, P.

journal: STL-QPSRvolume: 15number: 4year: 1974pages: 001-017

http://www.speech.kth.se/qpsr

http://www.speech.kth.sehttp://www.speech.kth.se/qpsr

STL-QPSR 4/1974

I. SPEECH PRODUCTION

A. COMPENSATION OR UNDERSHOOT: EFFECT OF SPEAKING RATE O N JAW MOVEMENTS D U R I N G THE PRODUCTION OF FINNISH DIPHTHONGS

A P i l o t S t u d y

P e r t t i Hurme ( U n i v e r s i t y o f T u r k u , F i n l a n d )

A b s t r a c t : The e x p e r i m e n t r e p o r t e d i n t h i s p a p e r was p l a n n e d t o i n v e s t i g a t e j a w movemen t s d u r i n g t h e p r o d u c t i o n o f F i n n i s h d i p h t h o n g s , w i t h s p e c i a l r e f e r e n c e t o t h e n o t i o n s u n d e r s h o o t and c o m p e n s a t i o n . The a p p a r a t u s d e s c r i b e d by C o o k e r ( 1 9 7 3 1 was u s e d f o r m a k i n g r e c o r d i n g s o f j a w m o v e m e n t s . T e n t a t i v e e v i d e n c e was p r o d u c e d f o r t h e C o m p e n s a t i o n H y p o t h e s i s : t h e r e i s v e r y l i t t l e o r no u n d e r s h o o t i n j a w movemen t s a s s p e a k i n g r a t e i s i n c r e a s e d . However , t h e m a i n e m p h a s i s o f t h e p r e s e n t s t u d y was on d e v e l o p i n g a m e t h o d o l o g y t o i n v e s t i g a t e j a w movemen t s a c r o s s c h a n g e s i n s p e a k i n g r a t e .

0. I n t r o d u c t i o n

0 . 1 . B a c k g r o u n d

The j a w i s o n e o f t h e m o s t e a s i l y a c c e s s i b l e a r t i c u l a t o r s .

N e v e r t h e l e s s , t r a c k i n g o f m a n d i b u l a r movemen t s i s by no m e a n s

e a s y . I n r e c e n t y e a r s , v a r i o u s m e t h o d s f o r t r a c k i n g m a n d i b u l a r

movemen t s h a v e b e e n u s e d by a number o f s p e e c h s c i e n t i s t s .

F o r i n s t a n c e , j a w movemen t s d u r i n g s p e e c h h a v e b e e n r e c o r d e d

by m e a n s o f v a r i o u s d i r e c t s e n s o r s a s w e l l a s by u s i n g p h o t o -

e l e c t r i c m e t h o d s , c f . L i n d b l o m ( 1 9 6 7 1 , O h a l a , H i k i e t a l . (19681 ,

M a c N e i l a g e , K r o n e s a n d Hanson ( 1 9 7 0 1 , O h a l a ( 1 9 7 0 1 , Sussman a n d

S m i t h ( 1 9 7 1 1, G r a n s t r e m ( 1 9 7 1 , 1 9 7 2 1 , S u s s m a n , M a c N e i l a g e a n d

Hanson ( 1 9 7 3 1 , Abbs ( 1 9 7 3 1 , C o o k e r ( 1 9 7 3 1 a n d Gay, U s h i j i m a

e t a l . ( 1 9 7 4 ) . The p r e s e n t s t u d y i s b a s e d on a m e t h o d d e v e l o p e d

by C o o k e r ( 1 9 7 3 1 .

0 . 2 . H y p o t h e s e s

Two m a j o r h y p o t h e s e s h a v e b e e n p r e s e n t e d t o d e s c r i b e

a r t i c u l a t o r movement a s a f u n c t i o n o f s p e a k i n g r a t e I= s p e e c h

t e m p o ) . O n l y o n e a r t i c u l a t o r , t h e j aw , i s d e a l t w i t h i n t h i s

s t u d y .

H y p o t h e s i s I wou ld s t a t e t h a t , a s s p e a k i n g r a t e i s i n c r e a s e d ,

t h e j a w d o e s n o t move f a s t e n o u g h t o r e a c h i t s t a r g e t p o s i t i o n .

T h u s , t h e r e w i l l b e some u n d e r s h o o t , t o u s e L i n d b l o m ' s ( 1 9 6 3 1

t e r m i n o l o g y . H y p o t h e s i s I w i l l b e c a l l e d t h e U n d e r s h o o t Hypo-

t h e s i s i n t h i s r e p o r t .

f i y p o t h e s i s 11, on t h e o t h e r h a n d , wou ld s t a t e t h a t , a s

STL-QPSR 4/1974

TIME

V

EXTENT HYPOTHESIS 1 HYPOTHESIS 2

Figure I-A-1. Schematic diagram of t h e t w o hypotheses: t h e Undershoot Hypothesis Ill and t h e Compensation Hypothesis ( 2 1 . J a w movement tracing during slow speech is marked with a solid line and during fast speech with a broken line.

Figure I-A-2. Schematic description of t h e technique used f o r recording j a w movements.

STL-QPSR 4/1974

1 . E x p e r i m e n t a l p r o c e d u r e s

1 .I. L . i n g u i s t i c m a t e r i a l

The same l i n g u i s t i c m a t e r i a l i s u s e d i n t h i s s t u d y a s i n a

f o r t h c o m i n g a c o u s t i c a n a l y s i s o f t h e e f f e c t o f s p e e c h t empo

on F i n n i s h d i p h t h o n g s by t h e p r e s e n t a u t h o r . T h e f o l l o w i n g

F i n n i s h d i p h t h o n g s were i n v e s t i g a t e d Cai, a i , zy, ti, oi, 61. dy. u i , y i i p l . Mcst o f t h e s e d i p h t h o n g s a r e c l o s i n g . i e i s a n o p e n i n g d i p h t h o n g a n d u i a n d y i a r e o f t h e same v o w e l I

h e i g h t . T h e morE o p e n c o m p o n e n t o f t h e d i p h t h o n g i s e i t h e r a I

l o w v o w e l o r a mid v o w e l . F o r a d e t a i l e d d i s c u s s i o n of F i n n i s h

d i p h t h o n g s , s e e W i i k ( 1 9 6 5 ) and K a r l s s o n 1 1 9 7 0 1 .

1 . 2 . R e g u l a t i o n o f s p e a k i n g r a t e

The f o l l o w i n g m e t h o d was u s e d t o r e g u l a t e d i p h t h o n g

d u r a t i o n : S y l l a b l e s were a d d e d t o t h e end o f a o n e - s y l l a b l e I

w o r d , t h u s l e n g t h e n i n g t h e word f r o m o n e t o f i n a l l y s i x

s y l l a b l e s . I n a l l , t h e t e n d i p h t h o n g s were p r o n o u n c e d by t h e

e x p e r i m e n t e r i n a f r a m e s e n t e n c e t h a t v a r i e d a s f o l l o w s :

[ t o i s t a k a : h - k e r : a n 1 h t e h t e r i h t e r i s t i h t e r i s t i m m e h t e r i s t i m m e k i n -

' R e p e a t o n c e '

A l l o f t h e r e s u l t i n g s i x t y w o r d s a r e p h o n o t a c t i c a l l y

p o s s i b l e i n F i n n i s h , e v e n t h o u g h n o t many o f t h e m d o e x i s t .

The o n l y v o w e l s t h a t a r e r e p r e s e n t e d i n t h e e n d i n g s a d d e d t o

t h e o n e - s y l l a b l e w o r d s [ i ] a n d ' e l , w h i c h a r e n e u t r a l i n I

r e g a r d t o v o w e l ha rmony . The v o w e l s were c h o s e n t o m i n i m i z e

c o a r t i c u l a t o r y e f f e c t s .

T h e r e a r e s t u d i e s f r o m s e v e r a l l a n g u a g e s i n w h i c h v o w e l

d u r a t i o n i s s h o r t e n e d when word l e n g t h i s i n c r e a s e d , e.g.

L e h i s t e ( 1 9701, L i n d b l o m a n d Rapp 11 971 1 a n d Nooteboom ( 1 9 7 2 1 . L e h t o n e n , h o w e v e r , g i v e s e v i d e n c e a g a i n s t t h i s p r i n c i p l e o f

i s o c h r o n y i n F i n n i s h , s h o w i n g t h a t i n F i n n i s h "word l e n g t h h a s

no s i g n i f i c a n t e f f e c t on t h e d u r a t i o n of t h e i n d i v i d u a l s o u n d

when t h e w o r d s a p p e a r i n t h e same s e n t e n c e p o s i t i o n " . [ L e h t o n e n

1 9 7 0 , 1 4 4 )

I n t h e p r e s e n t s t u d y t h e s u b j e c t was q u i t e p u r p o s e l y f o r c e d

t o p r o d u c e t h e t e s t w o r d s a c c o r d i n g t o t h e p r i c i p l e o f i s o c h r o n y .

STL-QPSR 4/1974

T h i s was d o n e by a s k i n g t h e s u b j e c t t o p r o n o u n c e t h e s e n t e n c e s

s o t h a t t h e f i r s t s y l l a b l e s o f t h e w o r d s [ w h e r e p r i m a r y s t r e s s

i s a l w a y s l o c a t e d i n F i n n i s h ) f o l l o w e d a t a b o u t r e g u l a r i n t e r -

v a l s . The s u b j e c t c o u l d n o t l e n g t h e n t h e m i d d l e word much, s i n c e

h e was s u p p o s e d t o k e e p s p e e c h tempo a p p r o x i m a t e l y t h e same.

Thus , s p e e c h tempo was v a r i e d o n l y i n t h e word c o n t a i n i n g t h e

d i p h t h o n g t o be i n v e s t i g a t e d , n o t i n t h e f r a m e s e n t e n c e i t s e l f .

A l l t h i s means t h a t t h e d a t a o b t a i n e d i n t h i s s t u d y a r e n o t

r e l e v a n t t o t h e p r o b l e m o f i s o c h r o n y i n F i n n i s h . However, i t s h o u l d b e n o t e d t h a t t h e l i n g u i s t i c m a t e r i a l o f t h i s e x p e r i m e n t

( f o r c e d i s o c h r o n y ) d i d n o t sound u n n a t u r a l t o F i n n i s h l i s t e n e r s

i n i n f o r m a l l i s t e n i n g t e s t s . ( R e c e n t l y , t h e p r o b l e m of i s o c h r o n y

i n F i n n i s h h a s been d i s c u s s e d by L e h t o n e n ( 1 9 7 4 ) and I i v o n e n

( 1 9 7 4 1 . The r e s u l t s o f I i v o n e n a r e i n l i n e w i t h t h o s e o f L e h i s t e ,

L indb lom and Nooteboom. However, t h e r e i s a b a s i c d i f f e r e n c e

be tween t h e two s t u d i e s : I i v o n e n ' s r e s u l t s a r e f r o m i s o l a t e d 1 w o r d s , L e h t o n e n ' s f r o m c o n n e c t e d s p e e c h . I t would seem t h a t

t h i s d i f f e r e n c e h a s a d r a s t i c i n f l u e n c e on t h e r e s u l t s . )

Measurements o f . d i p h t h o n g d u r a t i o n were made f r o m s p e c t r o -

g r a m s . The r e s u l t s f r o m a l l d u r a t i o n m e a s u r e m e n t s a r e g i v e n i n

Appendix A . A v e r a g e d i p h t h o n g d u r a t i o n a s a f u n c t i o n o f word

l e n g t h i s g i v e n i n T a b l e I-A-I.

T a b l e I-A-I. D i p h t h o n g d u r a t i o n i n w o r d s o f o n e t o s i x s y l l a b l e s : mean d u r a t i o n ( X I and s t a n d a r d e r r o r o f t h e mean (s;).

- s y l l a b l e s x

I t c a n b e s e e n t h a t mean d i p h t h o n g d u r a t i o n v a r i e s f r o m

24 c s ( s l o w , o n e - s y l l a b l e w o r d s ) t o 1 0 c s ( f a s t , s i x - s y l l a b l e

w o r d s ) . S t a n d a r d e r r o r s o f t h e mean a r e r a t h e r s m a l l . C l e a r l y ,

d i p h t h o n g d u r a t i o n v a r i e s a s a f u n c t i o n o f word l e n g t h . I n t h e

f o l l o w i n g , d i p h t h o n g d u r a t i o n w i l l b e u s e d a s a n i n d i c a t o r o f

s p e e c h tempo.

1 . 3 T e c h n i q u e f o r t r a n s d u c i n g jaw movements

The e x p e r i m e n t r e p o r t e d i n t h i s p a p e r was c o n d u c t e d a t t h e

STL-QPSR 4/1974 5.

S p e e c h T r a n s m i s s i o n L a b o r a t o r y , u s i n g a t e c h n i q u e d e v e l o p e d by

H a r r y C o o k e r . A d e t a i l e d d e s c r i p t i o n o f t h e t e c h n i q u e u s e d i n

t h e p r e s e n t s t u d y f o r t r a n s d u c i n g j a w m o v e m e n t s h a s b e e n

p r e s e n t e d by C o o k e r ( 1 9 7 3 1 .

V a r i o u s t e c h n i q u e s c a n b e u s e d f o r t r a c k i n g m a n d i b u l a r

movemen t s . If s e n s i n g p r o b e s a r e u s e d , t h e p r o b e c a n b e

a t t a c h e d t o s e v e r a l p l a c e s , f o r i n s t a n c e , t o t h e l o w e r t e e t h

[ d i r e c t l y t o t h e b o n e ) . The p r o b e c a n a l s o b e a t t a c h e d t o

some p o i n t o n t h e s u r f a c e o f t h e l o w e r j a w . T h i s wou ld be

i n d i r e c t t r a c k i n g , s i n c e t h e p r o b e wou ld n o t b e d i r e c t l y

c o n n e c t e d t o t h e m a n d i b l e .

An i n d i r e c t t r a c k i n g t e c h n i q u e was u s e d i n t h e p r e s e n t

s t u d y . The p r o b e was a t t a c h e d t o t h e p o s t e r i o r u n d e r s u r f a c e

o f t h e c h i n d i r e c t l y o v e r t h e c e n t e r o f t h e body o f t h e 1 m a n d i b l e .

An a d j u s t a b l e s e m i - r i g i d p l a s t i c h e l m e t was u s e d f o r

a n c h o r i n g t h e j a w movement t r a c k i n g s y s t e m . A n e e d l e t y p e

p r o b e was a t t a c h e d t o a t h r e e - d i m e n s i o n a l a d j u s t m e n t s y s t e m

i n t h e a n t e r i o r o f t h e h e l m e t v i a a bonded wire s t r a i n g a g e .

T h e o u t p u t o f t h e movement t r a n s d u c e r ( t h e s t r a i n g a g e ) was

f e d t o a m i n g o g r a p h f o r p e r m a n e n t r e c o r d i n g . An a u d i o c u r v e

was a l s o made on a n o t h e r c h a n n e l o f t h e m i n g o g r a p h .

The t e c h n i q u e u s e d f o r t r a n s d u c i n g m a n d i b u l a r movemen t s

i s i l l u s t r a t e d i n F i g u r e I-A-2.

1 . 4 . C a l i b r a t i o n p r o c e d u r e s

The s y s t e m f o r t r a c k i n g m a n d i b u l a r movernents was c a l i b r a t e d

by i n s e r t i n g b i t i n g - b l o c k s o f 2 , 4 a n d 8 mm b e t w e e n t h e

i n c i s o r s . T h e s e c a l i b r a t i o n p o i n t s c a n b e a p p r o x i m a t e d q u i t e . I

s a t i s f a c t o r i l y w i t h a s t r a i g h t l i n e , l i n e a r r e g r e s s i o n : r =

.95. M e a s u r e m e n t s o f j a w o p e n i n g i n m i n g o g r a p h p a p e r m i l l i -

me te r s w e r e c o n v e r t e d t o m i l l i m e t e r s i n d i c a t i n g a c t u a l j a w

o p e n i n g w i t h t h e a i d o f a r e g r e s s i o n l i n e c o m p u t e d t o f i t t h e

c a l i b r a t i o n p o i n t s . Z e r o mm i n t h e s c a l e o f a c t u a l j a w o p e n i n g

l o r d i s p l a c e m e n t , o r a m p l i t u d e o f j a w movemen t ) i n d i c a t e s j a w

p o s i t i o n when t h e i n t e r - i n c i s o r d i s t a n c e i s z e r o , n o t when t h e

t e e t h a r e c l e n c h e d . I t was c o n s i d e r e d t o b e m o r e r e l i a b l e t o

h a v e t h e z e r o p o i n t r a t h e r c l o s e t o t h e c a l i b r a t i o n p o i n t s ,

s i n c e t h e r e was some d i s c r e p a n c y , e v e n t h o u g h s l i g h t , w i t h t h e

c a l i b r a t i o n p o i n t s a n d a l i n e a r a p p r o x i m a t i o n . J a w o p e n i n g

STL-QPSR 4/1974 6 .

m e a s u r e m e n t s f r o m t h e i n t e r - i n c i s o r z e r o p o s i t i o n c a n f a i r l y

r e l i a b l y b e c o n v e r t e d t o m e a s u r e m e n t s w i t h t h e c l e n c h e d

p o s i t i o n a s z e r o by a d d i n g 6 . 4 mm t o t h e m e a s u r e m e n t s .

1 . 5 . C r i t i c i s m o f i n d i r e c t j a w movement t r a c k i n g m e t h o d s

C o o k e r c r i t i s i z e s i n d i r e c t t r a c k i n g t e c h n i q u e s ( s u c h a s t h e

o n e u s e d i n t h e p r e s e n t s t u d y 3 a s f o l l o w s : " U n f o r t u n a t e l y , t h e

m o r e e a s i l y e m p l o y e d i n d i r e c t t r a c k i n g p r o b e s d o n o t y i e l d

a c c u r a t e i n f o r m a t i o n u n d e r a l l c o n d i t i o n s . When a t t a c h e d t o

t h e u n d e r s u r f a c e o f t h e c h i n , t h e p r o b e f o l l o w s n o t o n l y t h e

m a n d i b l e b u t a l s o t h e movemen t s o f t h e s o f t t i s s u e a s s o c i a t e d

w i t h t h e e l e v a t i o n a n d d e p r e s s i o n o f t h e l o w e r l i p . E x t e n s i v e

e x p e r i m e n t a t i o n w i t h v a r i o u s p r o b e s o n a l a r g e number of

s u b j e c t s l e d t o t h e c o n c l u s i o n t h a t i t was n o t p o s s i b l e t o e l i m i n a t e t h i s s o f t t i s s u e movemen t . Wheneve r t h e s p e a k e r s

p r o d u c e d b i - l a b i a l s o u n d s , t h e a c t i v i t y o f t h e m e n t a l i s a n d

d e p r e s s o r l a b i i i n f e r i o r a c t i n g upon t h e l n w e r l i p was t r a n s -

m i t t e d t o t h e p r o b e u n d e r t h e c h i n a n d a d d e d m o v e m e n t s t o t h e

r e c o r d s t h a t w e r e n o t c a u s e d by t h e m a n d i b l e . I n e f f e c t , t h e n ,

t h e r e c o r d s o b t a i n e d f r o m t h i s p o s i t i o n a r e a c o m p l e x c o m b i n -

a t i o n o f d i s p l a c e m e n t s and v e l o c i t i e s f r o m t h e a c t i o n o f t h e

o f t h e l o w e r l i p a n d t h e m a n d i b l e . " ( C o o k e r 1 9 7 3 , 91

S e v e r a l o f t h e d i p h t h o n g s i n v e s t i g a t e d i n t h e p r e s e n t s t u d y

c o n t a i n l a b i a l s e g m e n t s . A s shown i n t h e l e n g t h y q u o t a t i o n

a b o v e , t h e d a t a f o r t h e s e d i p h t h o n g s w i l l b e c o n t a m i n a t e d by

t h e movemen t s o f t h e l o w e r l i p . C o n s e q u e n t l y , t h e d a t a f o r

l a b i a l d i p h t h o n g s w i l l n o t b e q u i t e r e l i a b l e .

1 . 6 . V a r i a b l e s

I n a l l , t h e f o l l o w i n g s e v e n v a r i a b l e s w e r e m e a s u r e d f r o m t h e

j a w movement t r a c i n g s o r c o m p u t e d o n b a s i s o f t h e m e a s u r e m e n t s :

- d i p h t h o n g d u r a t i o n (=DIPH.DUR), m e a s u r e d f r o m s p e c t r o g r a m s

- t h r e e j a w o p e n i n g v a r i a b l e s : maximum e x t e n t o f j a w o p e n i n g d u r i n g t h e d i h t h o n g [ = E X T I , maximum e x t e n t o f j a w o p e n i n g d u r i n g t h e 07 i n t h e f i r s t word o f t h e f r a m e s e n t e n c e (=REF1 I , a n d maximum e x t e n t o f j a w c l o s u r e d u r i n g t h e t f o l l o w i n g t h e d i p h t h o n g (REF21

- d u r a t i o n o f j a w movement f r o m EXT t o REF2 ( = D U R )

- v e l o c i t y o f j a w c l o s i n g movement ( = V E L ) , c o m p u t e d by d i v i d i n g EXT m i n u s REF2 w i t h D U R

- p e a k v e l o c i t y o f j a w movement ( = P E A K ) , c o m p u t e d w i t h t h e a i d o f a t a n g e n t f i t t e d t o t h e j a w movement c u r v e a t t h e p o i n t o f maximum v e l o c i t y

I

STL-QPSR 4/1974 7 .

D i p h t h o n g d u r a t i o n m e a s u r e m e n t s were made w i t h an a c c u r a c y

o f o n e c e n t i s e c o n d and OUR m e a s u r e m e n t s w i t h a n a c c u r a c y o f

. 5 c s . An a c c u r a c y of .25 mrn was a t t e m p t e d i n j a w o p e n i n g

m e a s u r e m e n t s . Jaw movement v e l o c i t i e s a r e g i v e n i n mm/sec.

Some o f t h e measurement p o i n t s a r e shown i n F i g u r e I-A-3.

The r e s u l t s f r o m a l l m e a s u r e m e n t s a n d f o r a l l v a r i a b l e s a r e

g i v e n i n A p p e n d i c e s A and 8.

1 . 7 . R e f e r e n c e p o i n t s

I n a d d i t i o n t o t h e v a r i a b l e EXT (maximum e x t e n t o f j a w open-

i n g d u r i n g t h e d i p h t h o n g ) , j aw d i s p l a c e m e n t was m e a s u r e d a t two

r e f e r e n c e p o i n t s , . R E F I and REF2, i n o r d e r t o f i n d o u t a b o u t I ( p o s s i b l e ) c o n t e x t u a l e f f e c t s be tween j a w d i s p l a c e m e n t d u r i n g

t h e d i p h t h o n g a n d s e l e c t e d p o i n t s i n t h e f r a m e s e n t e n c e . I t

m i g h t p r o v e o u t t h a t t h e r e i s a n o v e r - a l l s h i f t i n j a w movement

a m p l i t u d e , s o t h a t t h e r e w i l l b e l a r g e v a l u e s o f EXT f o r l a r g e

v a l u e s o f REF1 and REF2 and s m a l l v a l u e s o f EXT f o r s m a l l v a l u e s

of t h e . r e f e r e n c e p o i n , t s . -

C o r r e l a t i o n c o e f f i c i e n t s w e r e computed s e p a r a t e l y f o r each

d i p h t h o n g t o see w h e t h e r t h e m e a s u r e d d a t a p o i n t s would show

s u c h a r e l a t i o n . he r e s u l t s OF t h e c a l c u l a t i o n s a r e g i v e n i n T a b l e I-A-11.

T a b l e I - A - I I . L i n e a r r e g r e s s i o n c o r r e l a t i o n c o e f f i c i e n t s o f EXT w i t h t h e two r e f e r e n c e p o i n t s , REF1 a n d REFZ.

d i p h t h o n g EXT/REFI EXT/REF2

.78 .20

.27 .79 .87

.49 .74 f i e .76 ' .68

The v a r i a b l e s EX7 and R E F 2 show a s t r o n g . p o s i t i v e c o r r e l a t i o n

r a t h e r s y s t e m a t i c a l l y . Jaw movement a m p l i t u d e s d u r i n g t h e

d i p h t h o n g and t h e f o l l o w i n g !t] seem t o b e r e l a t e d i n t h e m a n n e r d e s c r i b e d a b o v e : t h e r e i s a n o v e r - a l l s h i f t , i n j a w movement

a m p l i t u d e b e t w e e n t h e s e two n s i g h b o u r i n g ~ . s o u n d s .

On t h e o t h e r h a n d , c o r r e l a t i o n c o e f f i c i e n t s f o r EXT and REF1

show'much m o r e v a r i a b i l i t y . T h e r e a r e b o t h p o s i t i v e a n d negative,

- - - - " . - . - - - - ------ -- -- -- - -- .---- -- .. -- PAPER ACTUAL

F i g u r e I - A - 3 . R e p r o d u c t i o n o f jaw movement t r a c i n g s d u r i n g t h e p r o d u c t i o n o f t h e sentences c o n t a i n i n g t h e words h e i t e r i s t i ( 5 s y l l a b l e s l and h e i t e ( 2 s y l l a b l e s ) . Some o f t h e measurement p o i n t s a r e shown. EXT s tands f o r maximum e x t e n t o f j aw opening d u r i n g t h e d iph thong , REF1 and REF2 a r e t h e two r e f e r e n c e p o i n t s . The c a l i b r a t i o n p o i n t s as w e l l as t h e computed i n t e r - i n c i s o r ze ro p o s i t i o n a r e a l s o shown.

STL-QPSR 4/1974 9.

of t h e l o w e r c o m p o n e n t o f t h e d i p h t h o n g . ( N a t u r a l l y , t h e r e may

b e o t h e r c a u s e s of j a w movement v e l o c i t y v a r i a t i o n , s u c h a s

s p e e c h t e m p o . )

J a w c l o s i n g v e l o c i t i e s a n d p e a k v e l o c i t i e s f o r e a c h d i p h t h o n g

a r e g i v e n i n T a b l e I-A-IV.

T a b l e I-A-IV. Mearc v e l o c i t y IVEL) a n d mean p e a k v e l o c i t y (PEAK) o f j a w c l o s i n g movement a s w e l l a s s t a n d a r d e r r o r

I o f t h e mean f o r e a c h d i p h t h o n g .

VEL [iey ! i tdy] [ a i l r o i l i [ o i l r u i ] e r v i ] u

PEAK - x 7 1 6 5 62 57 5 4 44 3 8 1 5 13

T a b l e I - A - I V h a s b e e n a r r a n g e d i n a d e s c e n d i n g o r d e r o f j a w

movement v e l o c i t y . T h i s o r d e r r e s e m b l e s c l o s e l y t h e o n e o b t a i n e d

f r o m j a w movement a m p l i t u d e m e a s u r e m e n t s . On t h e w h o l e , j a w

movement v e l o c i t i e s ' s e e m t o i n c r e a s e w i t h d e c r e a s i n g v o w e l

h e i g h t . However , t h e d e s c e n d i n g o r d e r o b t a i n e d o n t h e b a s i s o f

a v e r a g e v e l o c i t i e s i s n o t v e r y r e l i a b l e , s i n c e s t a n d a r d e r r o r s

o f t h e m e a n s a r e r a t h e r b i g .

T h e s e r e s u l t s o f t h e e f f e c t o f p h o n e t i c q u a l i t y on t h e

a m p l i t u d e a n d v e l o c i t y o f j a w movemen t s a r e , on t h e w h o l e , i n

a g r e e m e n t w i t h p r e v i o u s s t u d i e s .

2 . 3 . E f f e c t of s p e e c h t e m p o on t h e a m p l i t u d e o f j a w m o v e m e n t s 1

A s m e n t i o n e d a b o v e , d i p h t h o n g d u r a t i o n (DIPH.DUR1 i s u s e d

a s a n i n d i c a t o r o f s p e e c h t empo i n t h e p r e s e n t s t u d y . I t c a n b e

s e e n f r o m A p p e n d i x A t h a t t h e r e i s some v a r i a t i o n i n t h e v a l u e s

o f t h e v a r i a b l e EXT w i t h i n e a c h d i p h t h o n g . Can t h i s v a r i a t i o n b e

e x p l a i n e d w i t h t h e v a r i a b l e DIPH.DUR, i . e , d o e s t h e a m p l i t u d e o f

j a w movemen t s d e p e n d o n s p e e c h t e m p o ?

I t wou ld b e e a s i e r t o a n s w e r t h e q u e s t i o n i f t h e r e were m o r e

d a t a a v a i l a b l e . However , i n t h e f o l l o w i n g a n a t t e m p t w i l l b e made

t o a n s w e r t h e q u e s t i o n . S e v e r a l c o m p u t a t i o n a l p r o c e d u r e s w i l l b e

made u s e o f .

I n t h e f i r s t p r o c e d u r e a l l d i p h t h o n g s i n e a c h o f t h e s i x

STL-QPSR 4/1974 i0.

s p e e c h tempo g r o u p s w e r e p o o l e d . The r e s u l t s o f t h e c o m p u t a t i o n s

a r e g i v e n i n T a b l e I-A-V.

T a b l e I-A-V. A l l d i p h t h o n g s o c c u r r i n g i n w o r d s w i t h t h e same number o f s y l l a b l e s p o o l e d . Mean v a l u e s f o r t h e v a r i a b l e EXT a s w e l l a s s t a n d a r d d e v i a t i o n a n d s t a n d a r d e r r o r o f t h e mean.

- s y l l a b l e s x s s j ;

1 1 . 9 1 . 4 .4

None o f t h e d i f f e r e n c e s be tween t h e means i s s t a t i s t i c a l l y

s i g n i f i c a n t . T h i s i s n o t s u r p r i s i n g , s i n c e s t a n d a r d d e v i a t i o n s

a r e r a t h e r h i g h . The p r o c e d u r e o f p o o l i n g a l l d i p h t h o n g s ,

i r r e s p e c t i v e o f p h o n e t i c q u a l i t y , i s n o t s a t i s f a c t o r y . U n f o r t u n -

a t e l y , c o m p a r i s o n s o f mean EXT v a l u e s f o r e a c h d i p h t h o n g i n

v a r y i n g s p e a k i n g r a t e s a r e n o t p o s s i b l e b e c a u s e o f s c a r c i t y o f

d a t a .

A n o t h e r p r o c e d u r e i s t o s t u d y t h e c o r r e l a t i o n o f t h e v a r i a b l e s

EXT and 0IPH.OUR. S t r o n g p o s i t i v e c o r r e l a t i o n would mean t h a t a s d i p h t h o n g d u r a t i o n d e c r e a s e s a l s o t h e a m p l i t u d e o f jaw move-

m e n t s d e c r e a s e s .

L i n e a r c o r r e l a t i o n o f v a r i a b l e s EXT and DIPH.DUR i s v e r y low, r= .05, w i t h a l l t h e d i p h t h o n g s p o o l e d . The c o r r e l a t i o n

c o e f f i c i e n t s f o r each d i p h t h o n g a r e g i v e n i n T a b l e I-A-6.

C o r r e l a t i o n c o e f f i c i e n t s f o r t h e v a r i a b l e s EXT and DIPH.DUR show v e r y much v a r i a t i o n , b u t on t h e w h o l e t h e y a r e r a t h e r low.

E v i d e n t l y , v a r i a t i o n o f j a w movement a m p l i t u d e c a n n o t b e e x p l a i n e d

w i t h t h e v a r i a b l e d i p h t h o n g d u r a t i o n .

On t h e o t h e r hand , t h e v a r i a b l e s DUR ( d u r a t i o n o f jaw c l o s i n g

movement f r o m EXT t o REF21 and DIPH.DUR a r e c o r r e l a t e d : r= . 6 1 , which i s s t a t i s t i c a l l y h i g h l y s i g n i f i c a n t ( p < . l ) . Jaw movements

a r e e x e c u t e d i n l e s s t i m e when s p e e c h tempo i s i n c r e a s e d .

2 .4 . E f f e c t o f s p e e c h tempo on jaw movement v e l o c i t i e s

Jaw movement v e l o c i t i e s f o r a l l d i p h t h o n g s a r e g i v e n i n

STL-QPSR 4/1974

Table I-A-VI. Correlation coefficients of the variables EXT, VEL and PEAK with the variable DIPH.DUR.

in Appendix A . The correlations of the velocity variables (VEL

and P E A K ) with the speech tempo variable (0IPH.DUR) are given in

Table I-A-VI. The number o f data pairs from which the correlations have been computed is only five or six. Few of the correlations

are statistically significant, possibly because of the small 1 number of data pairs. However, a fairly clear trend can be seen.

The velocity variables and diphthong duration are negatively

correlated: increasing velocities for decreasing diphthong duration.

2.5. Hypotheses

Hypothesis I would predict that the amplitude of: jaw movements

will decrease with increasing speech tempo. Hypothesis 11, on the

other hand, would predict that the amplitude of jaw movements

will remain about the same irrespective of tempo changes.

The present study can at best give only tentative evidence for or against the hypotheses. It would seem that the results of this

experiment give some evidence for the Compensation Hypothesis

(Hypothesis 11). It seems that the variables EXT and DIPH.DUR are not correlated, which means that the variation of the Variable EXT

cannot be explained with changes in diphthong duration.lThe Under-

shoot Hypothesis would predict that the variables EXT and DIPH.DUR show a strong positive correlation.1

No attempt will be made to include velocity changes in the argument for or against the two hypotheses. It would be quite

possible if there were more data available.

STL-QPSR 4/1974 12.

3. D i s c u s s i o n

I n summary, m a i n r e s u l t s o f t h i s s t u d y a r e t h e f o l l o w i n g :

- t h e m e t h o d u s e d t o r e g u l a t e d i p h t h o n g d u r a t i o n w o r k s i n a h i g h l y s a t i s f a c t o r y way

- p h o n e t i c q u a l i t y o f t h e d i p h t h o n g h a s i n f l u e n c e o n b o t h t h e a m p l i t u d e a n d v e l o c i t y o f j a w m o v e m e n t s

- s p e a k i n g r a t e has v e r y l i t t l e o r no e f f e c t o n t h e a m p l i t u d e o f j a w m o v e m e n t s

I - j a w movement v e l o c i t i e s d e p e n d o n s p e a k i n g r a t e : v e l o c i t i e s

a r e i n c r e a s e d a s s p e a k i n g r a t e i s i n c r e a s e d

- some r a t h e r t e n t a t i v e e v i d e n c e h a s b e e n h a s b e e n p r e s e n t e d f o r t h e C o m p e n s a t i o n H y p o t h e s i s o f a r t i c u l a t o r movement

- j a w d i s p l a c e m e n t c a n b e r e g u l a t e d v e r y p r e c i s e l y ; c f . t h e r e l a t i v e l y s m a l l v a r i a t i o n o f t h e v a r i - a b l e EXT a c r o s s c h a n g e s i n s p e a k i n g r a t e

- i n f a s t s p e e c h t h e j a w i s a r e l a t i v e l y f a s t a r t i c u l a t o r w i t h maximum p e a k v e l o c i t i e s o f t h e o r d e r o f 9 0 mm/sec

The r e s u l t s o f t h i s s t u d y s h o u l d h e r e g a r d e d a s t e n t a t i v e . The

l i n g u i s t i c m a t e r i a l was s m a l l a n d t h e r e was o n l y o n e e x p e r i m e n t a l

s u b j e c t . T h e s e r e a s o n s make d i f f i c u l t t o d r a w c o n c l u s i o n s on t h e

b a s i s o f t h e r e s u l t s .

The r e s u l t s o f Kuehn a r g u e s t r o n g l y f o r t h e use o f many s u b j e c t s

i n s p e a k i n g r a t e s t u d i e s : " D i f f e r e n t s p e a k e r s u s e d i f f e r e n t

s t r a t e g i e s t o i n c r e a s e s p e a k i n g r a t e , i . e . by t r a d e - o f f s i n d i s -

p l a c e m e n t vs . v e l o c i t y . " ( K u e h n , D. ( 1 9 7 3 ) A C i n e f l u o r o g r a p h i c

I n v e s t i g a t i o n o f A r t i c u l a t o r y V e l o c i t i e s ; c i t e d i n Gay, U s h i j i m a

e t a l . ( 1 9 7 4 , 621)

I n s p i t e of s e v e r a l s h o r t c o m i n g s , t h e m e t h o d u s e d i n t h e

p r e s e n t s t u d y s h o w s some p r o m i s e . W i t h some r e f i n e m e n t s , f o r

i n s t a n c e , e l i m i n a t i o n o f l i n g u i s t i c m a t e r i a l i n c l u d i n g l a b i a l

s o u n d s , t h i s m e t h o d c o u l d p o s s i b l y b e u s e d t o i n v e s t i g a t e t h e

p r o b l e m o f u n d e r s h o o t v s . c o m p e n s a t i o n i n m o r e d e t a i l .

A c k n o w l e d g e m e n t s

The e x p e r i m e n t r e p o r t e d i n t h i s p a p e r was c o n d u c t e d a t t h e

S p e e c h T r a n s m i s s i o n L a b o r a t o r y i n t h e s p r i n g o f 1 9 7 3 . The h e l p

a n d f r i e n d l y n e s s o f e v e r y b o d y a t t h e l a b i s g r a t e f u l l y acknow-

l e d g e d . I am e s p e c i a l l y i n d e b t e d t o C u n n a r F a n t f o r e n c o u r a g e m e n t

a n d i n s i g h t f u l d i s c u s s i o n s . T h i s e x p e r i m e n t wou ld n o t h a v e h e e n

p o s s i b l e w i t h o u t t h e a d v i c e , i n t e r e s t a n d h e l p , e v e n i n p r a c t i c a l

m a t t e r s , g i v e n by H a r r y C o o k e r , t h e d e v e l o p e r o f t h e e x p e r i m e n t a l

t e c h n i q u e u s e d i n t h i s s t u d y . I a l s o w i s h t o t h a n k F r e d K a l s s o n

STL-QPSR 4/1974

L i n d b l o m , B . ( 1 9 6 7 1 "Vowel d u r a t i o n a n d a m o d e l o f l i p m a n d i b l e c o - o r d i n a t i o n " , STL-QPSR 4 / 1 9 6 7 , 1 - 2 9 .

L i n d b l o m , 8 . a n d K . Rapp ( 1 9 7 2 ) " R e e x a m i n i n g t h e c o m p e n s a t o r y a d j u s t m e n t o f v o w e l d u r a t i o n i n S w e d i s h w o r d s " , O c c a s i o n a l P a p e r s , 1 3 , U n i v e r s i t y o f E s s e x , 2 0 4 - 2 2 5 .

L i n d b l o m , B . a n d 3. S u n d b e r g ( 1 9 7 1 1 " A c o u s t i c a l c o n s e q u e n c e s o f l i p , t o n g u e , j a w a n d l a r y n x movemen t " , PILUS, 2 , U n i v e r s i t y o f S t o c k h o l m .

Nooteboom, S . ( 1 9 7 2 ) P r o d u c t i o n a n d p e r c e p t i o n o f v o w e l d u r a t i o n . D o c t o r a l d i s s e r t a t i o n , U n i v e r s i t y o f U t r e c h t .

O h a l a , J . ( 1 9 7 0 1 A s p e c t s o f t h e c o n t r o l a n d p r o d u c t i o n o f s p e e c h . Work ing P a p e r s i n P h o n e t i c s , No. 1 5 , U n i v e r s i t y o f C a l i f o r n i a , L o s A n g e l e s .

O h a l a , J . , S . H i k i , S . H u b l e r a n d R . Harshman ( 1 9 6 8 ) " P h o t o - e l e c t r i c m e t h o d s o f t r a n s d u c i n g l i p a n d j a w m o v e m e n t s i n s p e e c h " , Work ing P a p e r s i n P h o n e t i c s , No. 1 0 , U n i v e r s i t y o f C a l i f o r n i a , Los A n g e l e s , 1 3 5 - 1 4 4 .

S u s s m a n , H . a n d K . S m i t h ( 1 9 7 0 1 " A t r a n s d u c e r f o r m e a s u r i n g m a n d i b u l a r m o v e m e n t s " , J . A c o u s t . S o c . A m e r . , 4 8 , 8 5 7 - 8 5 8 .

S u s s m a n , H. a n d K . S m i t h ( 1 9 7 1 I " J a w m o v e m e n t s u n d e r d e l a y e d a u d i t o r y f e e d b a c k " , 3 . A c o u s t .Soc .Amer . , 5 0 , 6 8 5 - 6 9 1 .

S u s s m a n , H . , P . M a c N e i l a g e a n d R . Hanson ( 1 9 7 3 ) " L a b i a l a n d m a n d i b u l a r d y n a m i c s . d u r i n g t h e p r o d u c t i o n o f b i l a b i a l s t o p c o n s o n a n t s 1 ' , J . S p e e c h H e a r . R e s . , 1 6 : 3 , 3 9 7 - 4 2 0 .

W i i k , K . ( 1 9 6 5 1 F i n n i s h a n d E n g l i s h V o w e l s . A n n a l e s U n i v e r s i t a t i s T u r k u e n s i s , 6 9 4 , T u r k u .

APPENDIX A

D a t a for t h e variables DIPH.DUR and DUR (in centiseconds),

EXT and REF2.(in millimeters) as well as VEL and PEAK (in millimeters per second):

'IPH OUR OUR EXT REF2 VEL PEAK

Lei] 22 2.25 17

5 11 I 0 6 10 10

[oil 1 25 2 16 12

3 14 12

STL-QPSR 4/1974

APPENDIX. A (continued)

OrpH OUR OUR EXT REF2 VEL PEAK

[ie] 1 2

3

STL-QPSR 4/1974

APPENDIX €3

Data f o r t h e v a r i a b l e s EXT, REF1 and REF2 ( i n mingogram

p a p e r mi l l i rne t e r s l :