Phonolog ica l Short-term M em ory and its R e la tionsh ip
to L anguage in W illiam s Syndrom e
J u lia G ran t and A nne tte K a rm ilo ff- S m ith
M R C Cognitive D evelopm ent U nit and U niversity C ollege , London, U K
S u san A . G a therco le
U niversity o f Bristo l, U K
S a ra h P a te rson
M R C Cognitive D evelopm ent U nit and U niversity C ollege , London, U K
P a tr ic ia H ow lin and M a rk D av ies
S t. G eorge’s H osp ita l M edica l Schoo l, London , U K
O r lee U dw in
W est Lam beth Com m unity C are Trust, London , U K
W i l liam s sy nd rom e ( W S ) , a ra re neu rodeve lopm en tal diso rd e r of g ene tic o rigin , is
ch a rac te rised by a re la tive advan tage o f language ove r m o re se r ious de fic its in
othe r cognitiv e dom ain s. In th is study the re lation sh ip o f phonological sh ort-te rm
m em ory to W S language , in p a rticu la r vocabula ry , w as exp lo red . U sing G a the rco le
and Baddeley’ s C h i ld ren ’ s T e st of N o nw o rd R ep etition ( C N R e p ) ( G a the rco le &
Baddeley , 1 9 9 6 ) , w e exam ined th e pa tte rn of pe rfo rm ance by W S p a rt ic ipan ts on
that task and com pared it to pe rfo rm ance on m easu re s o f recep tive language ,
v isu ospatia l ab ility , and dig it sp an . In addition , a com pariso n w as m ade of W S
nonw o rd repetition sco re w ith tho se o f tw o g roup s o f indiv idually m atched
no rm ally deve loping 5 -y ea r-o lds , on e on the bas is o f nonve rb a l tes t age and the
othe r on the bas is of ve rba l test ag e . A s expec ted W S r ep e tition sco re s show ed an
effec t of nonw o rd length bu t no t o f phonologica l com plexity . N o nw o rd s tha t w ere
re la tiv ely w o rd like w ere bette r repeated than nonw o rd s that w ere less w o rd like .
R e qu e s ts fo r re p rin ts sho u ld b e sen t to J u lia G ra n t , M R C - C D U , 4 T a v iton S tre e t , L o nd on W C 1 H
0 BT , U K ; em a il : j .g ra n t @ c d u .u c l.a c .u k .
W e sh o u ld like to than k the W ill iam s S y nd ro m e F o un d a tion fo r th e ir he lp in p u tting u s in to uch
w ith f am i lie s . O u r th ank s a re a lso ex ten ded to ou r pa rt ic ip an ts fo r th e ir co -o pe ra t ion an d to the i r
pa re n ts / g ua rd ians w ho se in te re st in the s tu dy w as a sou rc e of g re at enco ura g em en t . W e g ra te fu lly
a ck n ow led g e th e su gg e s tio n o f A l an Badd eley to u se th e C h i ld re n ’ s N o n w o rd R e p e tit io n T e s t w ith a
W S g ro up . W e a re a lso gra te fu l to C o rd e lia H e a d lam - W e lls w ho co l le c ted the adu lt w ord lik en es s
da ta fo r an u n de rg ra du a te pro jec t in th e P sych o log y D e p a rtm ent , U n ive rs ity C o l leg e , L o nd on .
Ó 1 9 9 7 P s ych o log y P ress , a n im pr in t o f E rlb aum ( U K ) T a y lor & F ra nc is L td
C O G N I T I V E N E U R O P S Y C H I A T R Y , 1 9 9 7 , 2 ( 2 ) , 8 1 ± 9 9
C N R ep score s w ere co rre lated w ith test ag es on T R O G , R a v en s , and d ig it sp an bu t
not w ith chrono log ica l age . T e st ag e on th e C N R e p w as a t a sim ila r leve l to th at on
T R O G , R av en s , and d ig it sp an bu t significan tly low er th an on BP V S . T he resu lts
lend support to the v iew tha t phono logy in W S i s a re la tive s treng th . In contra s t ,
d esp ite re lative ly good p roduc tiv e and recep tive vocabula ry , ce r ta in asp ec ts of the
p ro cesse s of w o rd lea rning in W S do no t se em to develop beyond th at o f no rm al 4 -
y ea r-o ld s. T h e good vocabula ry score s of old er ch ild ren and adults w ith W S m ay
be sim p ly due to th eir re la tive ly good phono log ica l sh ort-te rm m em ory .
INTRODUCTION
W illiam s syndrom e ( W S ) is found in abou t 1 in 2 5 , 0 0 0 l ive b irths ( Beuren,
1 9 7 2 ; Beuren, S chu lze , E be rle , H a rm janz , & A p itz , 1 9 6 4 ; C re ery , 1 9 5 3 ;
F ancon i , G ia rde t , S c h lesinger Butler, & Black, 1 9 5 2 ; G re enb erg , 1 9 9 0 ;
L igh tw ood , 1 9 5 2 ; W illiam s , Barratt-Boyes, & L ow e , 1 9 6 1 ) . W S is be lieved to
be a con tiguous gene d iso rder caused by hem izygous subm icroscop ic de letions
on chrom osom e 7 q 1 1 . 2 3 , in clud ing the elastin gene ( E w art et a l. , 1 9 9 3 ) and the
L I M -k inase 1 gene ( F rangiskak is et a l. , 1 9 9 6 ; T assabeh ji et a l. , 1 9 9 6 ) . It can be
d iagnosed on the basis o f a fluorescen t in situ hybrid isa tion ( F I S H ) test fo r the
de le tion of the elastin gene , w hich is found to be absen t in 9 8 % o f ind ividuals
d iagnosed as hav ing W S ( L owery e t a l. , 1 9 9 5 ). H igh leve ls o f w hole b lood
sero ton in have a lso been reported ( A ugust & R e alm uto , 1 9 8 9 ; M a rriage , 1 9 9 4 ) .
W S typ ically presen ts no evidence for foca l lesions in left o r righ t hem ispheres.
R athe r , differing pa tte rns of bra in grow th during em bryo- and ontogenesis resu lt
in d iffe ren t b ra in vo lum e proportions. W S c e reb rum is sm all , but the fron tal
co rtex acqu ires a near norm al vo lum e re la tionsh ip to the posterior cortex
( J e rn igan , Bellugi, S ow ell , D ohe rty , & H e sselink , 1 9 9 3 ; W ang , H e sse link ,
J e rn igan , D oherty , & Bellugi, 1 9 9 2 ) . R e cen t w ork by G a laburda , W ang , Bellugi,
and R o ssen ( 1 9 9 4 ) po in ts to cytoarch itecton ic anom alies in the fo rm of
exaggera ted horizon tal o rgan isa tion of neurones w ith in layers , increased ce ll
p a ck in g d e ns i ty th ro ug h o u t b ra in re g io n s , de c re ase d m ye l in a t ion , a nd
abnorm ally clustered and orien ted neurones , pa rticu la rly in the v isual co rtex .
P h eno typically ind ividuals w ith W S have a facial dysm orphology , w hich has
been charac terised as ``e lfin fac ies ’ ’ , m a lfo rm ations of the connec tive tissues ,
and card iovascu la r defec ts ( J ones & S m ith , 1 9 7 5 ; M c K u sick , 1 9 8 8 ; M o rris ,
D em sey , L eonard , D i lts , & Blackburn , 1 9 8 8 ) .
T he resu lting cogn itive pro file o f the syndrom e is unusua l in tha t a num ber of
stud ies have show n relatively prese rved lingu istic and face-p rocessing capac ities
despite low I Q s ( in the 5 0 s and 6 0 s in the m ain , w ith a range from 4 0 to 9 0 ) , and
se rious deficits on tasks requ iring the in tegra tion of v isuospa tia l in form ation , a s
w ell as num ber , m oto r , p roblem -so lving , and p lann ing tasks ( A rno ld , Y u le , &
M a rtin , 1 9 8 5 ; Bellugi, Bihrle, J ern igan , T rauner , & D ohe rty , 1 9 9 0 ; Bellugi,
M a rks , Bihrle, & S abo , 1 9 8 8 ; K a rm iloff- S m ith , 1 9 9 2 a , b ; K a rm iloff- S m ith ,
K l im a , Bellugi, G rant , & Baron C ohen , 1 9 9 5 ; U dw in & D enn is , 1 9 9 5 ) .
82 GRANT ET AL.
D e sp ite the re la tive streng th of verba l ab ilities in ind ividua ls w ith W S noted
by m any researchers , the resu lts o f recen t stud ies sugges t that w ith in language
itse lf there are peaks and va lleys. By adolescence , W S indiv idua ls typ ical ly have
a relatively w ell-deve loped expressive vocabu lary , bu t w ith a tendency to use
words tha t are precoc ious , unexpected , and som etim es inappropria te ( R o ssen ,
Bihrle, K lim a , Bellugi, & J ones , in p ress ; U dw in & D enn is , 1 9 9 5 ) . L ex ica l
abnorm ality in W S a lso m anifests itself in abnorm ally h igh produc tion of low
frequency words in w ord fluency tasks ( R ossen et a l. , in press) and in the
absence of som e of the norm al constra ints on w ord learn ing ( S tevens &
K a rm ilo f f- S m ith , subm itted ). S om e researchers ha ve sugge sted tha t the
syn tactic com ponent o f language is in tac t ( Bellugi, R o ssen , & K l im a , 1 9 9 5 ;
Brom berg , U l lm an , M a rcus , K e lley , & L ev ine , 1 9 9 4 ; R o ssen e t al., in p ress) ,
and this has led to the c la im tha t W illiam s syndrom e is a prim e exam ple of the
m odularity of language ( P inker , 1 9 9 4 ) . H ow ever , the hypo thesis o f in tact syntax
has been challenged in the ligh t o f resu lts from a num ber of new stud ies. T hese
inc lude im pairm ents in gram m atica l gender assignm ent in F rench and Ita lian -
speak ing ind ividua ls w ith W S ( C ap irc i , S abbadin i , & V o lterra , in press ;
K a rm ilo ff- S m ith e t al., in p ress ; V o lterra , S abbad ini , C ap irc i , P e zz in i , &
O sse lla , 1 9 9 4 ) , im pa irm en ts in le ft b ranch ing re lative c lause processing in
E ng lish -speak ing W S ind iv idua ls ( K a rm iloff- S m ith , V a lian , G rant , & H eske th ,
subm itted) , w ord order and m orphosyn tac tic e rro rs in the language of Ita lian -
speak ing W S ch ild ren ( V o lterra e t a l. , 1 9 9 4 ) , p rob lem s with the sensitivity to
subca tegorisa tion s truc tu res and the access and in teg ra tio n of sem antic
info rm ation into sen tence processing ( K a rm ilo ff- S m ith e t a l., subm itted ) ,
although they show norm al prim ing for isola ted w ords ( T y le r e t a l., in press).
M irror ing the d issoc ia tion usually found in people w ith W S be tween
ling u istic an d v isu ospa t ia l cog n ition , rece n t s tu d ie s h ave po in te d to a
dissocia tion betw een verba l and spa tia l short-term m em ory . F o r exam ple ,
although phonolog ica l short-te rm m em ory ( also know n as verbal o r aud ito ry
short-term m em ory) w as show n to be at the leve l of m en tal age ( U dw in & Y u le ,
1 9 9 0 ) o r h igher than m ental age ( M erv is , M o rris , Bertrand , & R ob inson , in
press) , spatial short-term m em ory turned ou t to be m ore se riously im pa ired
( V ic ari , Brizzolara , C a rle sim o , P ezzin i , & V o lte rra , 1 9 9 6 a ; W ang & Bellugi,
1 9 9 4 ) . V ic ari and co lleagues further report tha t th is d issoc ia tion is not rep lica ted
in long-te rm m em ory , w here bo th m oda lities a re im paired ( V ica ri et a l. , 1 9 9 6 a ).
In a further study of verba l short-term m em ory in W S , V ica ri and co lleagues
adm inistered a w ord span task in w hich w ord leng th , phono logical sim ilarity ,
and frequency were varied ( V icari , C a rlesim o , Brizzolara , & P e zz ini , 1 9 9 6 b ).
T h e W S pa rtic ipan ts show ed norm al sim ilarity and leng th effects in the ir
perform ance on the task , supporting the au thors ’ hypo thesis tha t phonolog ica l
encod ing m echan ism s are re la tive ly un im paired in W S . H ow ever , there w as a
reduced frequency effect in the W S p articipan ts ’ re sponses re la tive to a group of
norm ally deve lop ing ch ild ren. Both groups repea ted high frequency w ords be tte r
VERBAL MEMORY IN WS 83
than low frequency w ords , but the effect w as sm aller in the W S g roup . T his
find ing w as in terp reted by V icari and co lleagues as sugges ting an over-
dependence on phono log ica l encod ing in m em orising w ords and a re lative
absence of a contribution from long-te rm m em ory . T he au thors p ropose tha t the
pa ttern of W S pa rtic ipan ts ’ resp onses in m em ory tasks fits well w ith reports that
W S ind iv idua ls have re latively good phonology and vocabu la ry ( V o lterra et a l. ,
1 9 9 4 ) , bu t show abnorm al pa tterns of perfo rm ance on tasks such as verbal
fluency w hich requ ire e fficien t access to sem antic info rm ation sto red in long-
term m em ory ( R o ssen e t al., in p ress ; V o lterra et al., 1 9 9 4 ) .
T he p resen t study w as designed to investiga te the re la tionsh ip betw een
language and phono logical short-te rm m em ory in W S by m eans of a nonw ord
repe tition task , the C h ild ren ’ s T est of N onw ord R epetition ( C N R e p ) ( G a the rco le
& Baddeley , 1 9 9 6 ) . T he C N R ep w as deve loped by G a the rco le and Baddeley as a
tool w ith w hich to investigate phono log ica l short-term m em ory in ch ildren ,
w ith in a fram ework of the w ork ing m em ory m odel p roposed by Baddeley and
H itch ( 1 9 7 4 ) . In tha t m ode l , phonolog ical short-term m em ory is part of a m em ory
system w hich has th ree m ain com ponents : an atten tiona l system ( the cen tral
execu tive) , and two periphera l , l im ited-capac ity slave system s– the v isuospatial
ske tch pad and the articula tory loop or phono log ical short-term m em ory . T he
fo rm er is concerned w ith construc ting and m anipu lating v isual im agery , w hereas
the la tte r is spec ia lised for the tem porary sto rage of phonolog ica l m ateria l and
com prises a phonolog ica l sto re and a rehearsa l p rocess.
O n e advan tage of testing phonolog ica l short-term m em ory with nonw ord
stim uli as opposed to rea l w ords ( a s in w ord and d ig it span tasks) , is tha t the
resu lts a re no t confounded by d iffe rences in the fam iliarity of the stim uli. T his
can be particu larly true of a typ ica lly deve loping ch ildren fo r w hom rea l w ord
frequency m ay differ from norm al experience. P e rform ance on the C N R e p has
been found to be a be tter p red icto r o f vocabu la ry know ledge than aud itory d ig it
span in norm ally deve lop ing 4 - and 5 -yea r-old ch ild ren ( G a the rco le , W i llis ,
Baddeley , & E m slie , 1 9 9 4 ) , a nd to be c losely related to the reten tion by 1 0 -yea r-
o ld child ren of new ly acqu ired words ( A gu iar , 1 9 9 3 ) . It is also a m ore po werful
p red icto r than d igit span of single w ord read ing ability in 4 - , 5 - , and 8 -yea r-o lds
( G a the rco le , W i llis , & Baddeley , 1 9 9 1 a ; G a the rco le , W i llis , E m s lie , &
Baddeley , 1 9 9 2 ) , and of language com prehension in 4 - and 5 -year-o lds ( W i llis
& G a the rcole , 1 9 9 2 ) . M o reover , scores on an earlie r version of the C N R ep w ere
h igh ly correla ted w ith syn tac tic com plex ity in the spon taneous speech of
preschoo l ch ild ren ( A d am s & G a the rco le , 1 9 9 5 ). C h ild ren w ith spec if ic
language im pairm en t ( S L I ) have been found to be im paired on C N R ep
perfo rm ance , suggesting that S L I invo lves a deficit in phono logical short-term
m em ory ( Bishop, 1 9 9 6 ; G a thercole & Baddeley , 1 9 9 0 ) .
In a study of the assignm ent o f g ram m atica l gender in F rench-speak ing
indiv idua ls w ith W S , i t w as observed that the W S p articipan ts rep roduced
nonw ord stim uli m ore accura tely on the first p resen ta tion than a group of m uch
84 GRANT ET AL.
younger norm ally deve lop ing ch ild ren ( K arm iloff- S m ith , et al. in p ress). T h e
focus of tha t study w as language and all the nonw ords w ere on ly of tw o-sy llable
leng th . H ow ever , the resu lts suggested tha t nonw ord repe tition m ight be a
fru itful techn ique w ith w hich to exp lo re the relationship be tw een language and
phonolog ica l short-term m em ory in peop le w ith W S . T h e nonw ords in the
C N R ep vary in leng th ( from 2 to 5 sy llab les ) , phono logical com plex ity ( num ber
of consonan t c lus ters) , and the degree to w hich the nonw ords resem ble rea l
words. G athe rco le , W illis , E m slie , and Baddeley ( 1 9 9 1 b ) , u sing an earlie r
version of the C N R e p , found tha t in norm ally deve lop ing 4 - to 6 -yea r-o lds ,
pe rform ance on the C N R ep decreased w ith nonw ord leng th . P honolog ica l
com plexity had no sign ifican t effect on perfo rm ance bu t nonw ords tha t w ere
re latively word like w ere easier to repea t than those tha t were less word like.
In the light of the V icari et al. ( 1 9 9 6 b ) results for W S individuals on the word
span task m entioned earlier we can predict that W S p erform ance on the C N R ep
w ill show the norm al decrem ent in perform ance w ith stim ulus length. Because the
phonolog ical system in W S appears relatively unimpaired , phonological complex-
ity in the C N R ep stim uli should not sign ificantly affect performance. T he possible
effect of the wordlikeness variable on W S perform ance was less clear , as the
mechanism s underly ing the effect are no t yet fully understood . O ne of the
hypo theses considered by G athercole ( 1 9 9 5 ) was that the beneficia l effect of
wordlikeness on nonword repetition seen in norm ally developing children involves
the activation of stored lexical representation . If this were the case there would be
som e reason to expect a reduced wordlikeness effect in W S , g iven the evidence of
im pairm ent on tasks that requ ire access to long-term lex ical knowledge. H owever ,
more recen t w ork suggests that the wordlikeness effect is due to sensitivity to
patterns of phonotactic probabilities w ithin the language ( G a the rcole , F rankish ,
P ickering , & P eaker , subm itted). U nder this hypothesis , a wordlikeness effect in
W S nonw ord repetition sim ilar to that found in norm ally deve loping children
would support the v iew that phonology is a relative streng th in W S .
In addition to the ana lysis o f the effec ts o f the aforem entioned variables on
nonw ord repetition in W S ind ividuals , the relationships betw een perfo rm ance on
the C N R e p and scores on tw o tests of receptive language ability , a test o f
nonverba l v isuospa tia l ab ility , and d igit span w ere exam ined. F ina lly , C N R e p
scores for W S ind iv idua ls w ere com pared w ith da ta from norm ally deve lop ing
5 -yea r-o lds co llected by G a therco le and colleagues fo r an earlier study
( G a thercole , 1 9 9 5 ) .
METHOD
Participants
S eventeen ind ividua ls w ith W illiam s syndrom e took part in the study . T he re
were 9 fem ales and 8 m a les w ith an age range of 8 ; 3 to 3 5 ; 0 ( m ean 1 8 ; 7 ) . T h e
partic ipan ts w ere rec ru ited v ia the British W illiam s S yndrom e F oundation by
VERBAL MEMORY IN WS 85
m eans of a le tte r to paren ts / guard ians , inv iting them to fill in a questionnaire and
take part in the study . P a rticipants w ere from a range of socioeconom ic
backgrounds. T h ey had no h istory of m edical p roblem s that m igh t effec t
neuropsycho log ica l function ( such as hearing im pairm en t, se izu res , m en ing itis ,
o r card iac arrest). A l l those of schoo l age w ere in specia l schoo ls o r spec ia l un its
w ith in m ainstream schools.
Materials
T he fo llow ing tests w ere adm inistered :
1 . A sho rt form of either the W echsle r In telligence S ca le for C h ild ren
( W I S C - R o r W I S C - III U K ) ( W e chsle r , 1 9 7 4 , 1 9 9 2 ) o r the W echsle r A du lt
In te lligence S ca le ( W A I S - R U K ) ( W e chsle r , 1 9 8 1 ) , d epend ing on chrono log ical
age , consisting of tw o verba l sub tests ( V o cabu lary and S im ila rities) and two
perfo rm ance subtests ( Block D esign and P ictu re A rrangem ent). T h e W I S C w as
adm in iste red to 1 0 pa rtic ipan ts , and the W A I S to 7 . In addition , the D ig it S p an
from the W I S C w as adm inistered to a ll participan ts , regardless o f chronolog ical
age.
2 . T h e 4 0 nonw ords from the C h ildren ’ s T e st o f N onw ord R epe tition
( C N R e p ) , p resen ted as taped stim uli , reco rded fo llow ing the procedure
described by G a the rcole et al. ( 1 9 9 4 ) .
3 . A language com prehension task , the T est o f R ecep tion of G ram m ar
( T R O G ) ( Bishop, 1 9 8 3 ) .
4 . A te st o f recep tive vocabu lary , the British P ic ture V ocabu lary S ca le
( BP V S ), L ong F o rm ( D unn , D unn , W h etto n , & P in tilie , 1 9 8 2 ) .
5 . A nonverba l v isuospatia l test , R a vens C oloured P rogressive M a trices
( R avens C P M ) ( R a ven , 1 9 8 6 ).
Procedure
S om e of the W S p artic ipan ts w ere seen at the ir school o r tra ining cen tre . M o st o f
them , how ever , w ere tested at the C ogn itive D eve lopm ent U n it in L ondon. T hey
cam e to the U n it , u sually w ith a paren t , fo r a se ries o f v isits in w hich they a lso
took part in o ther studies. T h e testing was spread over tw o to three sessions.
V a rious orders o f adm inistration of tests were used , a lthough partic ipan ts w ere
usually g iven the BP V S first, because vocabu lary is often an area of re lative
streng th . T h is gave us an initia l ``ba llpa rk m easure ’ ’ o f one face t of their
language and gave partic ipan ts a positive sense of achievem ent.
Preparation and Administration of the CNRep
T he nonw ords were recorded by a m onolingual fem ale speaker , w ith in tervals o f
3 seconds be tween each item . T wo tapes w ere prepared , each w ith a d ifferen t
random ised order o f stim uli.
86 GRANT ET AL.
P a rtic ipan ts w ere a ll tes ted by the sam e exper im en ter ( G ran t). T h ey w ere
to ld tha t they were going to hear som e funny m ade-up w ords w hich they shou ld
repeat. A n exam ple w as g iven ( ``durzle . . . so can you say ( pause) `durzle ’ ’ ’ ) .
T h ey w ere to ld tha t they would hear m ore m ade-up w ords through headphones.
T h e tape w as then p layed , inc lud ing the taped instruc tions and prac tice item . N o
partic ipan t had d ifficu lty understand ing the task . If necessa ry , for exam ple
when no response was a ttem pted during the 3 -second gap , the tape w as stopped
to g ive the partic ipan t tim e to respond ( th is w as only necessary fo r one
partic ipan t). R esponses w ere scored im m ediately by the experim en te r as e ithe r
correc t o r incorrec t , w ith allow ance m ade for regional accen t. A l low ance w as
a lso m a de fo r ca ses w h ere an in d iv id ua l w as kn ow n to co n s is ten tly
m ispronounce one sound as ano ther ( e .g . / w / fo r / r / ). T h e responses w ere also
aud iotaped , so tha t uncerta in dec isions could be checked la ter. A t a la ter da te ,
the responses w ere scored aga in from the audio tapes by an independen t judge ,
who had no prio r in form ation about the partic ipan ts other than tha t they had
W S . T h e re w as 9 0 % a g reem ent betw een the tw o score rs. T h is is on ly som ewhat
low er than the 9 7 % a g reem ent betw een tw o scorers ob tained by G athercole e t
al. ( 1 9 9 4 ) on a norm al g roup , so w as considered sufficien tly h igh to w arran t
using fo r analysis the scores obta ined by the on-line m ethod w here lip
m ovem ents w ere also ava ilab le .
W o rd likeness judgem ents o f the taped stim uli w ere ob ta ined from 2 0
un de rg radu a te stud en ts ( w ith equ a l n um be rs h ea ring e ach o f th e tw o
presenta tion orders). T h e studen ts w ere asked to rate each nonw ord on a scale
of 1 ( ``no t very like a w ord a t a ll ’ ’ ) to 5 ( ``ve ry like a w ord ’ ’ ). T h e tape w as
stopped after each nonw ord to allow the participan t to m ake a judgem ent o f
word likeness. M e an ra tings were ca lcu lated fo r each nonw ord .
RESULTS
Verbal and Performance IQ
F irst , the rela tionsh ip be tw een verbal and perform ance scores on the W I S C a nd
W A I S w as exam ined to see w hether th is group of W S indiv idua ls show ed the
re lative advan tage on verbal scores found in several o ther stud ies. S ho rt form
verbal and perform ance I Q sco res w ere calcula ted according to the fo rm ula
given in S attler ( 1 9 8 1 ) . F loor w as set a t 5 1 , to m in im ise artefactua l d ifferences
( com puted floor scores ranged from 4 5 to 5 1 and favoured verbal I Q ) . M e an I Q
and sca led scores are presented in T ab le 1 .
T h e verbal and perform ance sca led scores w ere en tered into a m ixed-design
M A N O V A , w ith subgroup ( W I S C o r W A I S ) a s the betw een-subjects variab le.
S co res on the verba l sub tests were sign ifican tly h igher than scores on the
perform ance subtests [F ( 1 , 1 5 ) = 7 . 0 4 , P = . 0 1 8 ] . T h e effec t o f subgroup w as also
sign ifican t , w ith the group tested on the W A I S a chieving higher scores
[F ( 1 , 1 5 ) = 1 0 . 4 4 , P = . 0 0 6 ] . A s the data in T ab le 1 show , ve rbal scores w ere
VERBAL MEMORY IN WS 87
h igher than perfo rm ance scores in bo th subgroups and the in terac tion betw een
subgroup and test type w as not sign ificant [F ( 1 , 1 5 ) = 0 . 0 1 , P = . 9 4 ] .
W i th respec t to the effect o f subgroup in th is analysis , it w ou ld have been
surp rising not to have found such a d ifference g iven the reports in the lite ra tu re
that , in retest situa tions , ave rage increases of be tw een 4 and 1 7 po in ts a re seen if
in itial testing on the W I S C is fo llow ed by testing on the W A I S w hen participan ts
have reached the appropriate age ( see refe rences in S a ttler , 1 9 8 1 , p . 1 4 9 ; A ve ry ,
S late , & C h avan , 1 9 8 9 ) . M o reover , in a recen t longitudinal study , U dw in ,
D av ies , and H ow lin ( 1 9 9 6 ) found sign ifican t inc reases in verbal , p erfo rm ance ,
and fu ll I Q ( m ean increases of 9 , 8 , a nd 1 1 po ints , respective ly) in ind ividuals
w ith W S tested first on the W I S C a nd la ter on the W A I S . A s the m ean
d iffe rences in the presen t study ( o f 1 4 and 1 1 po in ts fo r the verbal and
perfo rm ance sub tests respective ly) w ere w ith in the range of those found by o ther
resea rchers , it seem s reasonab le to assum e that they w ere due to the usua l effec t
o f the tw o different test instrum ents used to m easure I Q . F o r the rem ain ing
analyses , the refo re , the partic ipan ts w ere trea ted as a single group.
Effect of Nonword Length and PhonologicalComplexity on Repetition
T he m ean num bers of item s correct fo r each sy llable leng th are show n in T ab le
2 . W S pe rfo rm ance w as adverse ly affected by increasing nonw ord leng th from 2
to 4 sy llab les. P e rform ance on nonw ords con tain ing 5 syllab les , how ever , w as
no w orse than on those item s con tain ing 4 sy llables.
T he effect o f nonw ord leng th ( num ber of sy llables) w as exam ined toge ther
w ith the effec t o f phono log ical com plex ity ( p resence or absence of consonant
c luste rs) in an analysis o f variance , w ith item s as the random fac tor. T h e re w as a
sign ifican t e ffect of nonw ord leng th [F ( 3 , 3 2 ) = 1 5 . 3 4 , P < . 0 0 1 ]. H ow ever , the re
w as no effec t o f phono log ica l com plex ity [F ( 1 , 3 2 ) = 3 . 2 3 , P > . 0 5 ] , and no
sign ifican t in teraction be tw een nonw ord leng th and phono log ical com plex ity
TABLE 1Mean Verbal and Performance WISC and WAIS Scores
(and Standard Deviations)
W ISC (n = 1 0 ) W A IS (n = 7 )
V er ba l I Q 6 0 . 9 9 ( 1 6 . 0 7 ) 7 4 . 4 7 ( 4 . 2 9 )
P e rfo rm ance I Q 5 4 . 4 6 ( 7 . 0 9 ) 6 5 . 9 1 ( 8 . 5 9 )
V er ba l S S 2 . 8 5 ( 0 . 7 5 ) 5 . 2 9 ( 0 . 8 1 )
P e rfo rm ance S S 1 . 5 0 ( 2 . 9 3 ) 3 . 8 6 ( 1 . 6 0 )
N o te : S S , sc a led sco re s .
88 GRANT ET AL.
[F ( 3 , 3 2 ) = 0 . 4 3 , P > . 0 5 ] . T h is pa tte rn of resu lts m irrors tha t reported by
G a therco le et al. ( 1 9 9 1 b ) fo r norm al 4 - to 6 -yea r-o lds.
Post-hoc ( N ew m an± K eu ls) tests revea led tha t the W S p artic ipan ts show ed a
sign ifican t decline in repe tition accuracy as the nonw ords increased in leng th
from 2 to 3 , P < . 0 5 and from 3 to 4 sy llables , P < . 0 5 . H ow ever , a s sta ted earlier ,
pe rform ance on 4 syllab le item s w as no be tte r than perfo rm ance on 5 sy llab le
item s. G a the rco le e t a l. ( 1 9 9 4 ) also found tha t the ir sam ple of 4 - to 9 -yea r-o lds
show ed no sign ificant d ifference be tw een scores on 5 sy llab le item s re la tive to
th e 4 sy l la b le st im u l i. T h e y su g g es ted th a t th e p rese n ce o f fa m il ia r
m orpho log ical m ultisy llab ic sequences in the 5 syllab le item s ( e.g . altupa tory ,
con fran tually , d e ferm ica tion ) m ay have offset the decline in repe tition accuracy
seen w ith increases of nonw ord leng th from 2 to 4 syllab les . T r i- and b i-sy llab ic
end ings like -a tory , -ua lly , and -ation m ay becom e chunked after repeated
exposure to recurring phono log ical pa tterns in da ily life , enab ling partic ipan ts to
process them as a un it in our nonw ord task .
A fu rthe r analysis o f variance was carried ou t to see whether the effect o f
syllab le leng th on perfo rm ance rem ained when tw o po ten tia lly confound ing
linguistic fac tors , nam ely , rated w ord likeness and num ber of m orphem es , w ere
en tered in to the ana lyses as covaria tes. T h e re was again a sign ifican t e ffec t o f
num ber of sy llables [F ( 3 , 3 0 ) = 1 3 . 8 9 , P < . 0 0 1 ] , a nonsign ifican t effec t o f
p rese nc e / abse nc e of c on son an t c lus te rs [F ( 1 , 3 0 ) = 1 . 0 5 , P > . 0 5 ] , an d a
nonsignifican t in teraction of the tw o fac tors [F ( 3 , 3 0 ) = 0 . 5 3 , P > . 0 5 ] .
Effect of Rated Wordlikeness on RepetitionPerformance
T w o subse ts o f stim uli w ere derived from the 4 0 nonw ord set fo llow ing the
procedure described by G a the rco le ( 1 9 9 5 ) . Item s in the tw o subse ts w ere
m atched for num ber of sy llab les , num ber of consonan t c luste rs , and num ber of
phonem es. O n e se t con tained 1 2 nonw ords of re latively low -rated word likeness ,
the other 1 2 nonw ords of h igh-ra ted w ord likeness.
T h e m ean num ber correc t for the low -w ord like set w as 7 . 8 8 ( S D 2 . 4 ) and fo r
the h igh-w ord like set 9 .2 9 ( S D 2 . 4 ) . P e rfo rm ance w as sign ificantly be tter on the
high-w ord like set than on the low -w ord like se t [t ( 1 6 ) = 3 . 6 8 , P = . 0 0 2 ] .
TABLE 2Mean Number of Correct CNRep Repetitions (and Standard Deviations) for Each
Syllable Length
2 S y lla b le 3 S yl la b le 4 S yl la b le 5 Sy l la b le
8 . 7 6 ( 1 . 0 9 ) 7 . 5 3 ( 1 . 5 5 ) 5 . 2 9 ( 3 . 2 9 ) 5 . 2 9 ( 3 . 1 8 )
VERBAL MEMORY IN WS 89
T he rela tionsh ip betw een scores on the low- and h igh-w ord like nonw ords
item s and vocabu lary know ledge as m easured by the BP V S w as exam ined by
m eans of corre lationa l ana lyses. BP V S scores and repe tition of the low -w ordlike
item s w ere som ew hat m ore h igh ly correlated , r = . 7 2 , P = . 0 0 2 , than w ere BP V S
scores and repetition of the h igh-w ordlike item s , r = . 6 4 , P = . 0 0 7 ( see F igs 1 and
2 ). P a rtia l co rrela tions w ere then carried ou t con tro lling for language age
( T R O G test age) and repe tition ab ility. T h is g ives an index of the strength of the
un ique rela tionsh ip be tw een each of the repe tition subscores and vocabu lary that
is independent o f language age. W i th T R O G te st age and repe tition score on the
low-w ord like item s partialled ou t , there w as a negative bu t nonsign ificant
re la tionsh ip betw een BP V S score and repetition of the h igh-w ordlike stim uli ,
r = ± . 0 2 9 3 , P = . 9 2 1 . In contrast , the re was a positive and sign ifican t rela tionsh ip
be tw een BP V S score and perfo rm ance on the low -word like stim uli w hen T R O G
FIG. 1. S c a tte rp lo t o f sco re s fo r low -w o rd l ik e i tem s as a fun c tio n o f BP V S ra w sco re s . ( D u e to
l im ited t im e fo r te s ting o ne p a rtic ip an t , a S h o rt F o rm BP V S w as ad m inis te re d . H is ra w score w as
the re fo re n o t in c lu ded in th is an a ly s is .)
90 GRANT ET AL.
test age and repe tition score on the h igh-w ordlike item s w ere partialled out ,
r = . 5 3 , P = . 0 5 . T h e d ifference be tw een these tw o correlations w as exam ined
using the procedure for testing the difference be tween tw o non independen t rs
desc ribed by H ow ell ( H ow ell , 1 9 8 7 ) . T h e re w as a sign ifican t d iffe rence be tween
the tw o corre lations , P < . 0 1 . G a therco le ( 1 9 9 5 ) found a sim ilar pattern in her
da ta from 4 -year-o ld norm ally deve loping ch ildren . In con trast , w hen these sam e
ch ildren had reached 5 years o f age , there w as no re la tionsh ip be tw een repe tition
of e ither type of nonw ord and vocabu lary know ledge.
Repetition Performance in Relation toChronological Age and Scores on TROG, BPVS, andRavens CPM
P e rfo rm ance on C N R e p in term s of raw scores w as not sign ifican tly corre la ted
w ith C A , r = . 4 6 , P > . 0 5 . H ow ever , C N R e p scores w ere significan tly corre la ted
FIG. 2. S c a tte rp lo t o f score s fo r h ig h-w o rd lik e i tem s a s a fu nc t io n of BP V S ra w score s .
VERBAL MEMORY IN WS 91
w ith test age ( T A ) on the o ther four tests ( C N R e p w ith T R O G T A , r = . 6 8 ,
P = . 0 0 3 ; w ith BP V S T A , r = . 7 7 , P < . 0 0 1 ; w ith D igit S pan T A , r = . 5 9 , P = . 0 1 2 ;
w ith R avens T A , r = . 5 0 , P = . 0 3 9 ) .
R aw scores fo r the C N R e p w ere converted to T A s on the basis o f the
norm ative da ta availab le fo r 4 - to 9 -year-o ld ch ildren ( G a the rco le e t al., 1 9 9 4 ) .
T A s fo r C N R e p , T R O G , BP V S , R avens , and D ig it S p an , p resen ted in T ab le 3 ,
revea l an uneven profile w ith vocabu lary com prehension ( BP V S ) outstripp ing
perfo rm ance on the other four tasks.
A w ith in -sub jec ts analysis o f variance on the five tests show ed a sign ificant
e ffec t o f test on test age [F ( 4 , 6 4 ) = 8 . 8 3 , P < . 0 0 1 ] . P e rfo rm ance on C N R e p w as
co m pare d w ith perfo rm ance on th e o ther fo ur task s. C N R e p T A w as
sign ifican tly low er than tha t for BP V S [t ( 1 6 ) = ± 4 .1 3 , P = . 0 0 1 ] . T h ere w ere
no o ther sign ifican t d ifferences. P erfo rm ance on C N R ep was no t sign ifican tly
d iffe rent from that on the m orphosyn tactic language com prehension task
( T R O G ) , the o ther short-te rm m em ory task ( D ig it S pan ) , o r the v isuospatia l task
( R avens M a trices) ( C N R e p w ith T R O G , [t ( 1 6 ) = 0 . 1 0 , P > . 0 5 ] ; C N R e p w ith
R avens [t ( 1 6 ) = 1 . 2 9 , P > . 0 5 ] ; C N R e p w ith D ig it S p an , [t ( 1 6 ) = 0 . 1 4 , P > . 0 5 ] ) .
In sum , a lthough perfo rm ance on the C N R e p w as positive ly and sign ifican tly
corre lated w ith test age on BP V S , T R O G , R a vens , and D ig it S p an , level o f
ab ility in term s of T A on the C N R e p w as significan tly low er than tha t on the
BP V S , whereas leve l o f ability on the C N R ep , T R O G , R avens , and D ig it S pan ,
re spec tive ly , d id no t differ.
Summary of Results
In certa in respec ts , the pattern of results fo r the W S p a rtic ipants on the C N R ep
resem bled that reported fo r norm ally developing ch ild ren . T he re w as a robust
e ffec t o f inc reases in leng th of m ateria l to be stored in phonolog ica l work ing
m em ory betw een 2 to 4 syllab les. N onw ords ra ted by norm al adu lts as rela tive ly
w ord like w ere easier to repea t fo r our W S pa rtic ipan ts than those w hich had
TABLE 3Mean (and Standard Deviations) Test Ages on CNRep,
TROG, BPVS, Digit Span, and Ravens
T est
M ea n (SD ) Te s t A ge
(m o nths)
BP V S 1 0 7 .0 6 ( 3 9 . 5 5 )
D i g i t S p a n 8 1 . 2 9 ( 1 4 . 5 1 )
C N R ep 8 0 . 6 5 ( 2 1 . 6 6 )
R av ens 7 3 . 5 9 ( 1 9 . 9 9 )
T R O G 8 0 . 1 2 ( 2 6 . 6 6 )
92 GRANT ET AL.
been ra ted as less word like . L ike norm al 4 -yea r-o lds , although unlike 5 -yea r-
olds , vocabu lary know ledge w as m ore c lose ly related to repe tition of low -
word like item s than to repe tition of high-w ord like item s.
H ow ever , con tra ry to w hat w ould be expected in a group of norm ally
develop ing ind ividua ls , C N R ep scores were not corre lated w ith chrono log ica l
age . Instead , C N R e p scores w ere corre lated w ith test age as assessed by T R O G ,
R a vens , D ig it S p an , and BP V S . C N R ep test age was sim ilar to tha t on T R O G ,
R a vens , and D ig it S p an , bu t sign ificantly low er than tha t fo r the BP V S .
COMPARISON WITH MATCHED CONTROLS
T h e outcom e of com paring resu lts across five d ifferen t tests necessa rily had to be
treated w ith som e cau tion , a s the norm ative da ta fo r those tests had been obta ined
from diffe ren t sam ples. T o confirm the W S p rof ile w ith respec t to the C N R ep ,
BP V S , and R avens scores ob ta ined in the presen t study , a com parison w as m ade
of W S C N R ep scores w ith data ob tained from norm ally deve lop ing ch ild ren .
G a therco le ( 1 9 9 5 ) h ad adm inistered the C N R ep , R avens C P M , and the BP V S to a
large group of norm al ch ild ren. It w as therefo re possib le to m atch partic ipan ts
from the W S sam ple w ith norm ally develop ing partic ipan ts on the basis of e ithe r
BP V S or R avens scores and to com pare the ir C N R ep scores d irectly.
In the m ain study , W S test age scores w ere higher on the BP V S than on the
C N R ep . W e the refo re expec ted tha t if pa rtic ipan ts w ere m atched on the basis o f
BP V S scores , the norm al 5 -yea r-o lds ’ C N R e p scores w ould be h igher than those
of the W S g roup . In con trast , b ecause W S C N R e p scores were no t d iffe ren t from
the ir R avens scores , in partic ipant pa irs m atched on the ir R avens scores there
shou ld be no d ifference in C N R ep scores.
T h e fo rm ation of m atched groups a lso prov ided the opportun ity of fu rthe r
investigation of the word likeness e ffec t found in the m ain study .
Method
T h e norm ally deve lop ing participan ts w ere a subse t o f a group of 7 0 ch ildren
who were tested at 4 years o f age and a year late r , a t 5 y ears , by G atherco le and
co lleagues on a ba tte ry of tasks which included BP V S ( S hort F o rm ) , R avens
C o loured P rog ressive M a trices , and the C N R ep ( see G a the rcole , 1 9 9 5 fo r fu rthe r
partic ipan t de tails). T he W S p a rtic ipants w ere the 1 7 de sc ribed in the m ain study
earlie r.
A s m ost o f the W S sam ple ’ s R avens and BP V S test ages w ere above 5 years ,
m a tch ing w as carried ou t w ith the norm ally develop ing ch ildren ’ s da ta at 5
yea rs , ra the r than at 4 yea rs. U n su rp rising ly , because of the W S uneven profile ,
it w as no t possib le to m atch any partic ipan ts using bo th R a vens and BP V S
scores. T w o sets o f m atched groups w ere therefo re fo rm ed : a R avens-m atched
group and a BP V S -m atched group .
VERBAL MEMORY IN WS 93
In the R avens-m atched group , w e succeeded in m atch ing 1 5 W S p a rticipan ts
to norm ally deve lop ing 5 -yea r-o lds on the basis o f bo th gender and R avens
( raw ) score to w ith in one po int. M e an R avens score fo r the W S pa rtic ipan ts w as
1 6 . 2 ( S D 4 . 3 ) and for the 5 -yea r-olds , 1 6 . 4 ( S D 4 . 5 ). M ean chrono log ica l age of
the W S ind iv iduals was 1 8 ; 1 0 ( S D 8 ; 4 ) and of the 5 -yea r-o lds 5 ; 3 ( S D 0 ; 2 ) .
In the BP V S -m atched group , we w ere ab le to m atch 7 W S p a rticipants w ith
5 -yea r-old ch ild ren using both gender and BP V S test age to w ith in 3 m on ths as
the m atching variab les ( the raw scores ob ta ined in the two studies w ere not
d irec tly com parab le as d iffe ren t form s of the BP V S had been adm iniste red ).
M e an BP V S test ages w ere 6 ; 1 ( S D 1 ; 1 0 ) and 6 ; 2 ( S D 1 ; 1 0 ) fo r the W S and 5 -
year-o ld participan ts , re spec tive ly. T h e m ean chronolog ica l age of the W S
subse t w as 1 1 ; 1 0 ( S D 2 ; 1 0 ) and fo r the 5 -yea r-o lds it w as 5 ; 3 ( S D 0 ; 3 ) .
Results
In the R avens-m atched group , the m ean C N R e p score fo r the norm al 5 -yea r-olds
w as 2 5 ( S D 5 . 3 2 ) and fo r the W S ind iv iduals 2 6 . 4 7 ( S D 7 . 5 4 ) . T he se scores w ere
no t sign ifican tly different from each other [t ( 1 4 ) = 0 . 6 5 , P > . 0 5 ] . A s expec ted ,
how ever , in the BP V S -m atched group the norm al 5 -year-o lds ’ C N R e p scores
w ere h igher than the W S sco res. T h e m ean C N R ep scores were 2 8 . 7 1 ( S D 3 . 4 )
and 2 0 . 7 ( S D 5 . 1 ) fo r 5 -yea r-olds and W S p a rticipan ts , re spec tive ly . T h e
d iffe rence be tw een the tw o groups ’ sco res w as sta tistica lly significan t bo th by t-
test [t ( 6 ) = 2 . 9 9 , P = . 0 2 ] , and by W ilcoxon , ca rried out as a m ore conservative
test because of the sm all num ber of partic ipan t pa irs , z = 2 . 0 2 , P = . 0 4 .
T he se resu lts confirm ed tha t the disc repancy be tw een the BP V S and C N R ep
scores found in the W S group w as no t typ ica l o f norm ally deve lop ing ch ild ren
w ith the sam e vocabu lary age . In fac t , C N R e p test age tended to be higher than
BP V S test age in the norm al 5 -yea r-o lds , w h ich is the opp osite of the pattern
found in W S .
G iven the sm all num bers in the BP V S -m atched group , the ana lysis o f the
w ord likeness e ffec t w as carried out on the R avens-m atched partic ipan ts ’ sco res
on ly . Both groups of R avens-m atched partic ipan ts scored better on the h igh-
than the low -w ordlike item s. M e an scores fo r W S w ere 9 .2 0 ( S D 2 . 0 8 ) and 7 . 8 0
( S D 2 . 3 7 ) fo r high- and low -wo rdlike item s , re spective ly . F or the 5 -yea r-o lds ,
the h igh- and low -w ord like item s w ere 8 .8 7 ( S D 1 . 8 8 ) and 7 . 6 0 ( S D 1 . 5 9 ) ,
re spec tive ly . T h e scores w ere en tered into a m ixed-design M A N O V A . T h e re
w as a sign ificant e ffect o f w ord likeness [F ( 1 , 2 8 ) = 1 9 . 0 2 , P < . 0 0 1 ] . T h ere w as
no effect o f g roup [F ( 1 , 2 8 ) = 0 . 0 7 , P > . 0 5 ] .
DISCUSSION
A s expected , the W S p a rtic ipan ts ’ sco res on the C N R ep show ed a norm al pattern
in te rm s of the leng th and com plexity variab les. T he sign ificant effec t o f
w ord likeness suggests that in the course of language acqu isition W S ind ividuals
94 GRANT ET AL.
bu ild up norm al represen tations of phono tac tic p robab ilities in the ir na tive
language , and supports the v iew ( K a rm iloff- S m ith e t al., in p ress ; V ica ri e t a l.,
1 9 9 6 b ; V o lterra e t al., 1 9 9 4 ) that phono logy is relatively un im paired in W S . In
con trast , the find ing of a stronger rela tionship be tween BP V S scores and
repe tition scores on the low -w ordlike stim uli , than be tw een BP V S and scores fo r
high-w ord like stim uli sugges ts that , un like norm ally develop ing ch ild ren ,
ind iv idua ls w ith W S co n tinue to re ly heav ily o n the ab ili ty to re ta in
phonolog ica l m aterial in short-te rm m em ory to support w ord learn ing . T h is
suggestion stem s from the fact that the W S d a ta resem ble those prev iously found
for norm ally develop ing 4 -yea r-o lds bu t not 5 -year-o lds ( G a the rco le , 1 9 9 5 ) . In
tha t study , there w as a stronger assoc ia tion of vocabu lary know ledge w ith
repe tition accuracy for low - than fo r h igh-w ord like nonw ords in 4 -yea r-o lds ,
wh ich had d isappeared by the tim e the ch ildren reached 5 yea rs o f age . O n the
basis of this and o ther ev idence , G a the rco le argued tha t the im portance of the
con tribu tion of phono log ical short-term m em ory to w ord lea rning during norm al
developm ent lessens be tween around 4 and 5 years. By 5 years, fac tors such as
the w ay in which lexical item s are in teg ra ted into the existing lex icon m ay exert
m ore of an effect than in earlier stages of w ord lea rn ing. In W S th is shift in the
ba lance of fac tors tha t influence word lea rn ing m ay be a ttenua ted . T h is fits we ll
w ith the find ings of stud ies on W S w h ich suggest an over-dependence on
phonolog ica l encod ing in w ord span tasks a longside im pairm en ts on tasks
requ iring effic ien t access to lex ica l rep resen tations in long-te rm m em ory
( R o ssen e t al., in press ; V ic ari et al., 1 9 9 6 a , b ; V o lte rra e t a l. , 1 9 9 4 ) . T he rela tive
absence of an in fluence of the lex icon itse lf on the acquisition of new w ords
would a lso exp lain w hy the W S p artic ipan ts in the F rench gender study
( K a rm ilo ff- S m ith et al., in p ress) never m is-repea ted nonsense w ords as rea l
words , som eth ing w hich the norm al 5 -year-o lds d id frequently .
T h e find ing that C N R ep scores w ere no t different from R avens , T R O G , o r
D ig it S p an scores confirm s the resu lts o f a num ber of ea rlie r stud ies tha t found
phonolog ica l short-term m em ory in W S to be at m en tal age ( U dw in & Y u le ,
1 9 9 0 ; V ica ri e t a l., 1 9 9 6 a ; W ang & Bellugi, 1 9 9 4 ) , and no t chrono log ical age
level. BP V S scores w ere high rela tive to C N R e p perform ance in the W S g roup ,
a pattern opposite to the one found in the young norm ally deve lop ing contro l
sub jects. R o ssen e t al. ( in p ress) sim ilarly found receptive vocabu lary level in
W S ind iv iduals to be higher than w ould be expected on the basis o f m en tal age.
H ow ever , in the ir study of the W illiam s syndrom e cogn itive pro file , M e rvis ,
M o rris , Bertrand , and R ob inson ( in p ress) , found ra ther d ifferent re la tionsh ips
am ong test scores , w ith aud itory short-term m em ory perfo rm ance superior to
nonverba l spa tia l ab ility and to recep tive language ( bo th syn tax and vocabu la ry).
T h e p rec ise pa ttern of rela tive strengths and w eaknesses in the W S cogn itive
pro file aw aits fu rthe r cla rifica tion .
O u r resu lts con tribu te to grow ing ev idence that , no tw ithstand ing som e claim s
to the con tra ry , language in peop le w ith W S is no t intact. P roblem s w ith certa in
VERBAL MEMORY IN WS 95
aspec ts of m orphosyn tax ( K arm ilo ff- S m ith et al. , in p ress ; V o lte rra et al., 1 9 9 4 ) ,
the integra tion of sem antic info rm ation in sen tence-processing ( T y le r e t a l. , in
p ress) , the non-adherence to certa in princ ip les constrain ing w ord lea rn ing
( S tevens & K a rm iloff- S m ith , subm itted ) , unusua l w ord use ( R o ssen et a l., in
p ress) , and , a s d em on stra ted in th e presen t s tudy , a con tinu ing strong
re la tionsh ip be tw een vocabu lary know ledge and short-term m em ory tha t is
no t seen beyond the age of 4 yea rs in norm al deve lopm ent , a ll sugges t that
peop le w ith W S on ly show a rela tive advantage of language over other dom ains.
W ith in the dom ain of language itself , and even w ith in the subdom ain of lex ical
acqu isition , the re a re bo th rela tive streng ths and w eaknesses.
M a nu sc rip t re c eived 2 4 J u ly 1 9 9 6
R e v ised m an usc rip t re c eived 2 6 N ov em be r 1 9 9 6
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96 GRANT ET AL.
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C re e ry , R . D . G . ( 1 9 5 3 ) . Id iop a th ic hy pe rc a lca em ia in in fa n ts. L an ce t , 2 , 1 7 ± 1 9 .
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W in d so r U K : N F E R - N e lso n .
E w a rt , A . K . , M o rr i s , C . A . , A tk in son , D . , J i n , W . , S t er ne s , K . , S p a llo n e , P . , D e a n S tock , A . , L e p pe rt ,
M . , & K e a ting M . T . ( 1 9 9 3 ) . H em izy go s ity a t th e e la s tin lo cu s in a d eve lop m en ta l d iso rd e r ,
W i l liam s syn dro m e . N ature G ene t ic s , 5 , 1 1 ± 1 6 .
F a nco n i , G . , G ia rd e t , P . , S c h le sin ge r Butler, H . , & Black, J . S . ( 1 9 5 2 ) . C h ron isch e H y pe rc a lca em ie
ko m bine rt m it O s teo sk le ro se , H y pe ra zo tam ie M in d e rw uschs u nd k og en i ta l M is sb i ld un gen .
H e lve t ica P aed ia tr ica A cta , 7 , 3 1 4 ± 3 3 4 .
F ra n g isk ak is , J . M . , E w a rt , A . K . , M o rris , C . A . , M er v is , C .B., Bertran d , J . , R o b in son , B.F ., K le in ,
B.P ., E nsin g , G . J . , E v e re tt , L . A . , G re e n , E . D . , P ro sch e l , C . , G u tow sk i, N . J . , N o b le , M . , A tk in son ,
D . L . , O d el be rg , S . J . , & K e a tin g , M . T . ( 1 9 9 6 ) . L I M -k ina se 1 h em izyg os ity im p lic a ted in
im pa i re d v isuo spa tia l co n st ruc t iv e co gn it ion . C e ll , 86 , 5 9 ± 6 9 .
G al a bu rd a , A . M . , W a ng , P . P . , Bellu gi, U . , & R o s sen , M . ( 1 9 9 4 ) . C y to arch ite cton ic an om a lies in a
gen et ic a lly ba sed d iso rd e r : W i l liam s sy nd ro m e. C o g ni tiv e N eu rosc ience an d N eu rop sy cho lo g y ,
N euro R ep or t , 5 , 7 5 3 ± 7 5 7 .
G at he rc o le , S . E . ( 1 9 9 5 ) . Is no nw o rd re pe t ition a te st o f p ho n olo g ica l m em o ry o r lo ng -te rm
kn ow led ge ? It a l l dep end s on th e n o nw o rd s . M em ory an d C og ni tio n , 23 , 8 3 ± 9 4 .
G at he rc o le , S . E . , & Bad deley , A . D . ( 1 9 9 0 ) . P h o no lo g ica l m em ory d e fic its in lan gu ag e d iso rd e red
ch ild re n : Is th er e a c au sal co nn ec tion . Jou rna l o f M em o ry a n d La n gu ag e , 2 9 , 3 3 6 ± 3 6 0 .
G at he rc o le , S . E . , & Bad deley , A . D . ( 1 9 9 6 ) . The ch ild ren’s te st o f n o nw o rd repe t ition . L o nd on : T h e
P sych o log ical C o r po ra tio n .
G at he rc o le , S . E . , F ra n k ish , C . R . , P ic ke ring , S . J . , & P e a ke r , S . ( s u bm itte d). P h o no tac tic con s tra in ts
in ch ild re n ’ s se ria l re c a ll .
G at he rc o le , S . E . , W i l li s , C . , Badd eley , A . , & E m s lie , H . ( 1 9 9 4 ) . T h e C h ild re n ’ s T e s t o f N on w ord
R e pe ti tio n : A t e st o f p h on olog ica l w ork in g m em o ry . M em ory , 2 , 1 0 3 ± 1 2 7 .
G at he rc o le , S . E . , W i l lis , C . , & Bad d eley , A . D . ( 1 9 9 1 a ). D i ffe ren tiating p ho n olo g ica l m em ory and
aw a re n e ss of rh ym e : R e a d in g and v o cab u la ry d eve lo p m en t in ch ild re n . B riti sh Jou rna l o f
P sy ch o lo gy , 8 2 , 3 8 7 ± 4 0 6 .
G at he rc o le , S . E . , W i ll is , C . , E m sl ie , H . , & Bad deley , A . D . ( 1 9 9 1 b ). T h e in flu en ce s o f nu m be r o f
sy llab le s and w ord likene ss on ch i ld re n ’ s re pe t ition o f n on w o rd s . A p p lied P sycho l in gu is tics , 1 2 ,
3 4 9 ± 3 6 7 .
G at he rc o le , S . E . , W i l li s , C . , E m s lie , H . , & Bad d eley , A . ( 1 9 9 2 ) . P ho no lo g ica l m em o ry and
vo cab u la ry d ev e lo pm en t du rin g the e a rly sch oo l y ea rs : a lo ng itud in a l stud y . D eve lo pm en tal
P sy ch o lo gy , 2 8 , 8 8 7 ± 8 9 8 .
G ree n b er g , E . ( 1 9 9 0 ) . In tro du c tio n to sp ec ia l issue on W i lliam s sy n dro m e . A m erica n Jo urn a l o f
M ed ica l G en e tic s , S up p lem en t , 6 , 8 5 ± 8 8 .
H ow e ll , D . C . ( 1 9 8 7 ) . Sta t is tica l m e th od s for p sy ch o lo gy . Bo ston : P W S - K e n t.
J e r n ig an , T . L . , Be llu g i, U . , S o w e ll , E . , D o h e r ty , S . , & H e s se l in k , J . R . ( 1 9 9 3 ) . C e re b ra l
m o rp ho lo g ica l d is t in ct io ns be tw een W il liam s an d D o w n sy nd ro m es . A rch ive s o f N eu ro log y ,
50 , 1 8 6 ± 1 9 1 .
J o n e s , K . L . , & S m ith , D . W . ( 1 9 7 5 ) . T h e W il liam s e lfin fa c ie s sy n dro m e : A n ew p er sp ec tiv e.
Jo u rn a l o f P ed ia tr ic s , 86 , 7 1 8 ± 7 2 3 .
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K arm ilo ff- S m ith , A . ( 1 9 9 2 b ). A b n orm a l p hen o typ es an d the cha l leng e s they po se to co nn ec tio n ist
VERBAL MEMORY IN WS 97
m o de ls o f d eve lop m en t. Techn ica l R epo r ts in P ara lle l D is tr ib u ted P ro ce ssing an d C o gn itiv e
N eu ro sc ien ce , TR .P D P .C N S.92 .7 , p p . 1 ± 4 7 C a rn eg ie M e llo n U n iv e rsi ty .
K a rm i lo f f - S m i th , A . , G r a n t , J . , Berth o u d , I . , D a v is , M . , H o w l in , P . , & U d w in , O . ( i n
p re ss). L a n gu ag e and W i lliam s sy nd rom e : H o w inta c t is ``in ta c t ’ ’ ? C h ild D evelop m en t.
K a rm a lo ff- S m ith , A . , K l im a , E . , Bellu gi, U . , G ra n t , J . , & Baro n-C o hen , S . ( 1 9 9 5 ) . Is th er e a so c ia l
m o du le ? L a n g uag e , fa c e p roce ss in g an d th eory o f m ind in su b jec ts w ith W il liam s syn d rom e ,
Jou rn a l o f C o g nit iv e N euro sc ien ce , 7 , 1 9 6 ± 2 0 8 .
K a rm ilo ff- S m i th , A . , T y le r , L . K . , V o ic e , K . , S im s , K . , U d w in , O . , H o w lin , P . , & D a v ies ,
M . ( s u bm it ted ). L in gu is tic d issoc iat io ns in W ill iam s sy nd ro m e: E v a lu at in g re c ep tiv e sy n tax in
o n-l in e an d o ff-l ine ta sk s.
K a rm ilo ff- S m i th , A . , V a lian , V . V . , G ra n t , J . , & H e sk eth , S . ( su b m itted ). E va lua ting syn tax in
W i ll iam s sy nd ro m e : A n im ita tio n s tu d y .
L ig h tw o o d , R . ( 1 9 5 2 ) . Id io pa th ic hy pe rc a lca em ia w i th fa ilu re to th riv e. P ro ceed ing s o f th e R oya l
S oc ie ty o f M edic in e , 4 5 , 4 0 1 ± 4 1 0 .
L ow e ry , M . C . , M o rris , C . A . , E w a rt , A . , Bro th m an , L . J . , Z h u , X . L . , L e on a rd , C . O . , C a re y , J . C . ,
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M ar ria ge , J . ( 1 9 9 4 ) . C entra l hyp e ra cus is in W ill ia m s syn dro m e . W i l l iam s S y nd ro m e A s so c ia tio n
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M o rr i s , C . , D em sey , S . , L e o na rd , C . , D i lt s , C . , & Blackb urn , B. ( 1 9 8 8 ). N at u ra l h is to ry of W ill iam s
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R a v en , J . C . ( 1 9 8 6 ) . R a vens p ro g re ss iv e m a tr ic e s an d vo cab u la ry sca le s . L o n do n : H . K . L ew is .
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S teven s , T . , & K a rm i lo ff- S m ith , A . ( s ub m itte d ). W o rd lea rn in g in a spec ial po p u la t ion : d o
in d iv idu a ls w ith W il liam s syn d rom e ob ey lex ica l co ns t ra in ts ?
T as sab eh ji , M . K . , M e tc a lfe , K . , F e rgu sson , W . D . , C a re tt , M . J . A . , D o re , J . F . , D o n na i , D . , R e a d , A . P . ,
P ro sche l , C . , G u to w sk i , N . J . , M a o , X ., & S h e e r , D . ( 1 9 9 6 ) . L I M -k ina se de tec ted in W ill iam s
syn d rom e . N a tu re G en et ic s , 13 , 2 7 2 ± 2 7 3 .
T y ler , L . K . , K a rm i loff- S m ith , A . , V o ic e , K . , S t e ven s , T . , G ra n t , J . , U d w in , O . , D a v ie s , M . , &
H ow l in , P . ( in p re ss ). D o peo p le w ith W S h av e b iza rre sem an tic s ? A p rim ed m on ito rin g s tu dy .
C o rtex .
U d w in , O . , D a v ie s , M . , & H o w lin , P . ( 1 9 9 6 ) . A lo ng itu d in a l s tud y o f cog n itive ab ili tie s an d
edu ca tion al at ta in m ent in W ill iam s sy nd ro m e . D eve lo pm enta l M ed ic in e a n d C h ild N euro lo gy ,
3 8 , 1 0 2 0 ± 1 0 2 9 .
U d w in , O . , & D e nn is , J . ( 1 9 9 5 ) . W i lli am s S y nd ro m e. In G . O ’ Brien & W . Y u le ( E d s .) , C lin ic s in
d ev e lop m enta l m edic in e: N o . 1 38 . B eh a viou ra l p h en o type s ( p p . 2 0 1 ± 2 0 4 ) . L o nd on : M a c k e ith .
98 GRANT ET AL.
U dw in , O . , & Y u le , W . ( 1 9 9 0 ) . E x p re ss ive lang uag e o f ch i ld re n w ith W il liam s syn dro m e. A m erican
Jo u rn a l o f M ed ica l G en e tics , S up p lem ent , 6 , 1 0 8 ± 1 1 4 .
V ic a ri , S . , Brizzolara , D . , C a rle s im o , G . A . , P e z z in i , G . , & V o lte rra , V . ( 1 9 9 6 a) . M em o ry ab i lit ie s in
ch ild re n w i th W il liam s syn d rom e . C o rte x , 3 2 , 5 0 3 ± 5 1 4 .
V ic a ri , S . , C a rl e sim o , G . , Brizzo lara , D . , & P ez z in i , G . ( 1 9 9 6 b ). S h o rt te rm m em ory in ch ild re n
w i th W ill iam s syn drom e : A re d uced con tribu tion o f lex ica l -s em ant ic k no w led ge to w o rd span .
N euro psy cho log ia , 3 4 , 9 1 9 ± 9 2 5 .
V o lte rra , V . , S a bb ad in i , L . , C a p irc i , O . , P e z z in i , G . , & O s se l la , T . ( 1 9 9 4 ) . L in gu is tic a b i lit ie s in
Ita lia n ch ild ren w ith W ill ia m s synd rom e . P re sen ta tion , W i lli am s S y nd ro m e A s so c ia tion S ix th
In tern a tion al P ro fe ss iona l C o n fe re nce. Build in g b rid ge s ac ro ss d isc ip lines : c og n i tio n to g en e , S a n
D i e go , C A .
W a n g , P . P . , & Bellug i, U . ( 1 9 9 4 ) . E v iden ce from tw o gen e tic sy nd ro m es fo r a d isso c ia tio n b etw ee n
ve rb a l an d v isua l- sp at ia l sho rt- te rm m em ory . Jo u rn a l o f C lin ica l an d E xp e rim enta l N euro psy -
ch o lo gy , 1 6 , 3 1 7 ± 3 2 2 .
W a n g , P . P . , H e s se l ink , J . R . , J e rn ig an , T . L . , D o he rty , S . , & Bellug i, U . ( 1 9 9 2 ) . T h e sp eci fic
neu rob ehav iora l p ro file o f W S is a ssoc ia ted w ith n eoce re be lla r hem isp he ric p re ser va tion .
N euro log y , 4 2 , 1 9 9 9 ± 2 0 0 2 .
W e c hs le r , D . ( 1 9 7 4 ) . W e ch s le r in te l lig en ce sca le fo r ch i ld ren – R ev ise d U K . L o n do n : T h e
P sych o log ical C o r po ra tio n .
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VERBAL MEMORY IN WS 99
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