Processing of Syntactic Movement in Children with Cochlear Implants

Zara Waldman

CUNY - Second Examination

July 2013

Content Areas for Today’s TalkLanguage Development in Children with Cochlear Implants

Typical and Atypical Syntax Development

The relationship between working memory and syntax processing

And eventually… how these three areas fit together and rationale for further exploration of these topics.

Cochlear Implants• CI are internal, biomedical devices that enable

people with damaged cochleae to experience the sensation of hearing

• Usually implanted in children at 6-12 months– In the past, implantation occurred after 12 mos.– Period of auditory deprivation/altered access has

profound effect on language development

• So, how DO children with CI develop language?– Sensitive periods

• Experience-independent• Experience-dependent

Language Outcomes in CIExperience-Independent

• Earlier CI = better standardized language scores (Connor, Heiber, Arts & Zwolan, 2000; Connor, Craig,

Raudenbush, Heavner & Zwolan, 2006; Nicholas & Geers, 2006, 2007)– Older CI recipients widen the gap between typical,

hearing (NH) children while younger CI recipients shorten it (Niparko, Tobey, Thal, Eisenberg, Wang, Quittner & Fink, 2010; Hay-McCutcheon, Kirk, Henning, Gao & Qi, 2008)

• The “magic” of 1 year of CI use– CI results in burst of vocabulary, speech (Tomblin,

Barker, Spencer, Zhang & Gantz, 2005)

• Because this “magic” appears to wane by 4-5 years of use (Connor et al., 2006)

• And few CI users reach typical levels of language, even by age 5 (Svirsky, Teoh & Neuberger, 2004)

• Morphology still not quite right (Nicholas & Geers, 2007)

• When within-group differences were explored, Duchesne, Sutton & Bergeron (2009) identified vocabulary and syntax as two major deficits for children with CI

• And great variability remains• These studies are framed as an effect of

chronological development, not necessarily accounting for variations in language experience

Experience-Dependent• CI children 4 mos. behind acquiring first

words, 3 mos. behind acquiring word combinations (Nott, Cowan, Brown & Wigglesworth, 2009)

• Slower reaction time to word recognition (Grieco-Calub, Saffran & Litovsky, 2009)

– This might be influenced by perception• Still part of experience!

• Poorer fast mappers, especially after 14 mos. (Houston, Stewart, Moberly, Hollich & Miyamoto, 2012; Tomblin, Barker & Hubbs, 2007)

– But better if you could hear before your CI! (Houston et al., 2012)

– And if you had more experience using your CI! (Tomblin et al., 2007)

• Also found in language scores! (Nicholas & Geers, 2006; Niparko et al., 2010)

• Reading scores agree with Duchesne et al. (2009) (Geers et al., 2008)

CI Children and Development of Complex Language (Syntax)• Despite typical overall language scores from CI subjects…– Grammar was so disordered further comparison to typical

children wasn’t possible (Caselli, Rinaldi, Varuzza, Giuliani & Burdo, 2012)

– Only 36% of children implanted under 4 years have age-appropriate syntax (Nikolopoulous, Dyar, Archbold & O’Donoghue, 2004)

• Majority of difficulties centered in verb cases (Szagun, 2000),

article omission (Caselli et al., 2012, Szagun, 2004), and syntactic movement (Geren, 2010)

– Suggests that the issue starts as a perceptual deficit, but failure to correct syntax after multiple exposures might indicate a more involved cause

– But, syntax is better with more maternal input and better pre-CI hearing (Szagun, 2004b)

What is Syntactic Movement?• One part of the sentence is relocated– This disrupts subject-verb-object structure

• A trace exists in the gap left behind by the relocated part– When the listener reaches the gap, they must reactivate the

filler noun to complete the sentence (Love & Swinney, 1996; Roberts, Marinis, Felser &

Clahsen, 2007; Marinis & Van Der Lely, 2007; Love, 2007)

– This filler is stored in working memory

Subject Question:[Which dog] 1 t1 licked Jessie?

Object Question:[Which girl] 1 did the dog lick t1?

How can we confirm this is the underlying process?• Priming studies– Evidence of trace reactivation in children as young as

4 years old (Love, 2007)

• Eye-tracking– Difference in eye movements between wh-questions

and yes/no questions (Sussman & Sedivy, 2003)

– Longer reading times for object relatives and questions (Traxler, Morris & Seeley, 2002)

– Significant proportion of looking time during the gap focused on the gap-filler (Dickey, Choy & Thompson, 2007)

• Even true in aphasic participants!

Processing Syntactic Movement• Typical children develop their ability to comprehend

and produce syntactic movement between ages of 2-3 years (Stromswold, 1995)

– But children as young as 15 mos. Have shown recognition of pictures in response to wh-questions (Seidl, Hollich & Juscyzk, 2003)

– VERY FEW (>2%) children show evidence of NO syntactic movement abilities (deVilliers, Roeper, Bland-Stewart & Pearson, 2008)

• And there is a hierarchy to syntactic movement– Object relatives and questions are more difficult than subject

relatives and questions (Friedmann, Belletti & Rizzi, 2008)

• And syntactic comprehension is sensitive to the preferences/interest level of the child (Hurewitz, Brown-Schmidt, Thorpe, Gleitman &

Trueswell, 2000)

– As well as semantic plausibility (Friedmann et al., 2008)

What do we know about syntactic movement abilities in

children with CI?

Is this deficit unique?

Language Disorder & SyntaxCochlear Implants

• Comprehension and production of relative clauses and wh-questions significantly worse than their NH peers (Friedmann & Sztermann,

2005, 2010, 2011)

– Only 61% of object relatives were correct and 70% of those used resumptive pronouns

• Deaf subjects were aided by explicit noun phrases (Berent, 1996)

– Possibly suggestive of a “semantic strategy”

• Poor accuracy in repetition of relatives and wh-questions (Friedmann

& Sztermann, 2011)

Specific Language Impairment (SLI)• Comprehension and production of

relative clauses and wh-questions signifcantly worse than their typical peers (Deevy & Leonard, 2004; Marinis & van der Lely, 2007; Friedmann & Novogrodsky, 2006, 2011)

• Trace reactivation shown with priming only at verb offset (Marinis & van der Lely, 2007)

– Might be “semantic strategy” (sort of likely)

– Might be delayed trace (very likely)• They can process the gap but not

always its relationship to semantic components in the sentence (Friedmann & Novogrodsky, 2006)

– As suggested by paraphrasing

But Why?So far, the research community wants us to

blame it on “thematic role confusion”• But, this might imply total inability to

comprehend/produce syntactic movement

• But, this might impede the usage of resumptive pronouns

• But, even aphasics can process

syntactic movement

When two populations have “thematic role confusion,” we

should consider a shared cause. Perhaps, their parsing is in tact, but something else is not quite

right.

What’s something we SHOULD consider?• Processing a sentence requires:

Parsing: ability to break downcomponents of sentences, understand those components, and reconfigure them

• How we use knowledge of syntax/grammar

[Functional] Working Memory (WM):ability to store, process, and control attention while parsing

• How we remember, activate, and integrate all the sentence components together

Working Memory can be defined by capacity…• Idea that there is a finite amount of WM

resources in the brain, amount is unique to every individual (Just & Carpenter, 1992)

– Typical adults with lower reading span capacity had poorer sentence comprehension (King & Just, 1991; Just & Carpenter,

1992)

• And typical children! (Gaulin & Campbell, 1994)

• Much more of these WM resources are used to comprehend sentences with syntactic movement (King & Just, 1991; Just & Carpenter, 1992)

– Even evidenced in eye tracking and ERP (Traxler, Williams, Blozis &

Morris, 2005)

Or by interference• The simultaneous activation of related

concepts while trying to retrieve one specific concept (Gordon, Hendrick & Levine, 2002)

– Adequate inhibition of this excess activation enables the brain to retrieve the specific concept

• When subjects had to retain related items in memory, comprehension of cleft sentences and relative clauses was poorer (Gordon, Hendrick & Levine, 2002; Fedorenko,

Gibson & Rohde, 2005)

– Poorer comprehension also occurs from syntactic interference, when verb plausibility is manipulated (Van Dyke & McElree, 2006)

So, is there evidence of working memory issues in populations with language/syntax

impairment?

And again, is this working memory issue unique to one population?

Working Memory & CI

• CI children have poorer backward/forward WISC digit spans than their NH peers (Cleary, Pisoni & Geers, 1999;

Cleary, Pisoni & Kirk, 2000; Pisoni & Cleary, 2001; Burkholder & Pisoni, 2003)

• Implicit sequencing is also impaired, as shown on SIMON task (Pisoni, Conway, Kronenberger, Henning & Anaya, 2008)

– Link to how grammar is learned?• Better digit span also linked to faster

articulation of sentences (Pisoni & Cleary, 2001; Tobey, Geers, Morchower, Perrin, Skellett,

Brenner & Torretta, 2000)

– Better WM = faster retrieval?

Working Memory & SLI• Reading span capacity and sentence

comprehension linked in SLI population (Leonard, Ellis-Weismer, Francis,

Tomblin & Kail, 2007; Montgomery & Evans, 2009)

– Nonword repetition abilities also linked to sentence comprehension (Montgomery, 1995)

– Performance is poorer than age matched peers, but not peers matched for syntax (Montgomery & Evans, 2009)

• Abilities affected more by sentence complexity than sentence length (Marton & Schwartz, 2003)

• Are not helped by slowed presentation (Montgomery, 2004)

• Do not appear to rehearse or have a particular pattern/strategy to help them retain information (Marton & Schwartz, 2003)

Do these working memory deficits play a role in syntactic processing?

It would appear so, but it more specific research is needed to affirm

this hypothesis.

Rationale for Research• Two groups, but ONE problem!• There is evidence that “thematic role reversal” is not

the whole story• We need to confirm if another factor, working

memory, could be responsible – Or could be the shared, underlying issue between

populations with syntactic deficits– For children with CI, need more precise research in working

memory (!)

• The opportunity to study both processes (syntax and working memory) in concert with each other, at the very moment they are happening

Questions & Discussion

With my many thanks to:Richard Schwartz, PhD

Klara Marton, PhDDerek Houston, PhD

for their knowledge and guidance in helping me prepare for this examination.