The Auditory Scaffolding Hypothesis (ASH, Conway et al., 2009) suggests that sound experience provides a scaffolding for the development of sequencing and timing behavior. As a result, a period of auditory deprivation from birth should imply sequencing and timing behavior impairments. The socio-clinical consequences of this hypothesis are not trivial. In fact, considering that sequencing and timing behavior are among the building blocks of many cognitive functions (e.g. Lashley, 1951), if the ASH is correct swift action should be taken to ensure each deaf newborn to have his/her sense of hearing restored with adequate technologies. In view of the above, I considered crucial to test predictions that follow from the ASH to verify its validity. My dissertation is composed by five chapters: an introductory chapter (1), three experimental chapters (2, 3 and 4) and a final summary (5). Participants of the studies reported in chapters 2 and 3 were Deaf adult signers, whereas in chapter 4 deaf children with cochlear implant. In chapter 1, I introduce the ASH in detail, explaining its theoretical basis. Then, I highlight some criticisms. The chapter contains also a digression on the nature of sequencing and timing behavior following the taxonomy described in Dehaene et al. (2015). I explain that assessing sequencing and timing behavior should take as a reference point the Dehaene taxonomy, and that my agenda consists indeed of the assessment of the ASH at different levels of this taxonomy. Chapter 2 reports a set of four experiments assessing the ability of Deaf and hearing adults to acquire artificial grammars presented in the visual modality. Even if the strategy adopted by the two groups of participants seemed to differ, Deaf as well as hearing adults were able to acquire artificial grammars at different levels of the Chomsky hierarchy, from finite state grammars to context-sensitive grammars. Chapter 3 presents a study on visual statistical learning with sequentially presented stimuli in Deaf and hearing adults. Moreover, this study investigated the relationship between visual statistical learning skills and literacy. Visual statistical learning scores positively correlated with reading comprehension scores in the hearing group. The correlation was also positive in the Deaf group, but it was not significant. Even if the Deaf group had lower reading skills than the hearing group, the two groups exhibited comparable visual statistical learning abilities. Chapter 4 contains a study on timing abilities in children with cochlear implant. Children’s ability to construct the abstract representation of regular isochronous stimuli was assessed using a warning-imperative task. Participants’ results were extremely variable. Nevertheless, the vast majority of children performed within standard limits. The last chapter, chapter 5, is a summary of the arguments and evidence against the ASH that I presented in the previous chapters. To sum up, in this dissertation I argue that the ASH cannot be accepted as valid hypothesis and that sequencing and timing behavior can fully develop also in people with delayed/no access to auditory experience. Therefore, input other than sound should sustain these skills, which are among the building blocks of many high-level cognitive functions.

L’ipotesi dell’auditory scaffolding (ASH, Conway et al., 2009) suggerisce che gli stimoli sonori costituiscano un’impalcatura per lo sviluppo di abilità di tipo sequenziale e temporale. Di conseguenza, un periodo di deprivazione uditiva dalla nascita dovrebbe comportare dei disturbi significativi nello sviluppo di queste abilità. Le ripercussioni cliniche e sociali di questa ipotesi sono importanti. Infatti, se si considera che abilità di tipo sequenziale e temporale sono fondamentali per lo sviluppo di molte funzioni cognitive (si veda ad esempio Lashley, 1951), se la ASH fosse valida bisognerebbe garantire ad ogni neonato sordo, il più rapidamente possibile, la possibilità di sentire con l’aiuto di tecnologie adeguate. Lo scopo della mia tesi di dottorato è quello di testare diverse predizioni generate dall’ASH, per determinarne la sua validità. La mia tesi è composta da cinque capitoli: un capitolo introduttivo (1), tre capitoli sperimentali (2, 3 e 4) e un capitolo conclusivo (5). Nel capitolo 1 introduco la ASH, spiegandone le basi teoriche ed evidenziandone le criticità. Questo capitolo contiene anche una digressione sulla natura delle abilità di tipo sequenziale e temporale sulla base della tassonomia proposta in Dehaene et al. (2015). Infine, introduco l’obiettivo della mia tesi di dottorato, ovvero testare la ASH considerando i differenti livelli di rappresentazione delle sequenze proposti da Dehaene et al. (2015). Il capitolo 2 contiene una serie di quattro esperimenti che indagano l’abilità di adulti sordi e udenti di apprendere grammatiche artificiali presentate in modalità visiva. Anche se le strategie messe in atto dai due gruppi di partecipanti per svolgere il compito differiscono, sia i partecipanti sordi che i partecipanti udenti si sono rivelati capaci di apprendere grammatiche artificiali poste a differenti livelli della gerarchia Chomskyana. Il capitolo 3 presenta uno studio si apprendimento statistico e del rapporto tra quest’ultimo e la letto-scrittura in adulti sordi segnanti e udenti non segnanti. I punteggi nel test di apprendimento statistico correlano positivamente con quelli ottenuti nei test di letto-scrittura per quanto riguarda gli udenti, la correlazione è positiva anche nei sordi, ma non raggiunge la significatività. Anche se i sordi hanno dei punteggi in lettura inferiori rispetto agli udenti, i due gruppi mostrano abilità di apprendimento statistico comparabili. Il capitolo 4 riporta uno studio sulle abilità temporali in bambini con impianto cocleare. Usando il compito del “warning-imperative”, si sono investigate le abilità dei bambini con impianto cocleare di costruirsi una rappresentazione mentale di una cadenza sonora regolare. Anche se i risultati sono stati molto variabili, la maggior parte dei bambini ha mostrato una performance nella norma. L’ultimo capitolo, il capitolo 5, è un sommario degli argomenti che confutano la ASH presentati nei capitolo precedenti. Ricapitolando, in questa tesi di dottorato sostengo che la ASH non può essere accettata come valida perché in assenza di input sonoro o in situazioni di ritardato accesso agli stimoli uditivi è possibile sviluppare abilità di tipo sequenziale e temporale. Lo sviluppo di queste abilità, quindi, deve essere sostenuto anche da ulteriori tipi di input.

(2018). Processing and learning of sequential patterns in deaf and hearing individuals: differences and similarities. (Tesi di dottorato, Università degli Studi di Milano-Bicocca, 2018).

Processing and learning of sequential patterns in deaf and hearing individuals: differences and similarities

GIUSTOLISI, BEATRICE
2018

Abstract

The Auditory Scaffolding Hypothesis (ASH, Conway et al., 2009) suggests that sound experience provides a scaffolding for the development of sequencing and timing behavior. As a result, a period of auditory deprivation from birth should imply sequencing and timing behavior impairments. The socio-clinical consequences of this hypothesis are not trivial. In fact, considering that sequencing and timing behavior are among the building blocks of many cognitive functions (e.g. Lashley, 1951), if the ASH is correct swift action should be taken to ensure each deaf newborn to have his/her sense of hearing restored with adequate technologies. In view of the above, I considered crucial to test predictions that follow from the ASH to verify its validity. My dissertation is composed by five chapters: an introductory chapter (1), three experimental chapters (2, 3 and 4) and a final summary (5). Participants of the studies reported in chapters 2 and 3 were Deaf adult signers, whereas in chapter 4 deaf children with cochlear implant. In chapter 1, I introduce the ASH in detail, explaining its theoretical basis. Then, I highlight some criticisms. The chapter contains also a digression on the nature of sequencing and timing behavior following the taxonomy described in Dehaene et al. (2015). I explain that assessing sequencing and timing behavior should take as a reference point the Dehaene taxonomy, and that my agenda consists indeed of the assessment of the ASH at different levels of this taxonomy. Chapter 2 reports a set of four experiments assessing the ability of Deaf and hearing adults to acquire artificial grammars presented in the visual modality. Even if the strategy adopted by the two groups of participants seemed to differ, Deaf as well as hearing adults were able to acquire artificial grammars at different levels of the Chomsky hierarchy, from finite state grammars to context-sensitive grammars. Chapter 3 presents a study on visual statistical learning with sequentially presented stimuli in Deaf and hearing adults. Moreover, this study investigated the relationship between visual statistical learning skills and literacy. Visual statistical learning scores positively correlated with reading comprehension scores in the hearing group. The correlation was also positive in the Deaf group, but it was not significant. Even if the Deaf group had lower reading skills than the hearing group, the two groups exhibited comparable visual statistical learning abilities. Chapter 4 contains a study on timing abilities in children with cochlear implant. Children’s ability to construct the abstract representation of regular isochronous stimuli was assessed using a warning-imperative task. Participants’ results were extremely variable. Nevertheless, the vast majority of children performed within standard limits. The last chapter, chapter 5, is a summary of the arguments and evidence against the ASH that I presented in the previous chapters. To sum up, in this dissertation I argue that the ASH cannot be accepted as valid hypothesis and that sequencing and timing behavior can fully develop also in people with delayed/no access to auditory experience. Therefore, input other than sound should sustain these skills, which are among the building blocks of many high-level cognitive functions.
CECCHETTO, CARLO
GUASTI, MARIA TERESA
deafness,; sequences,; auditory; scaffolding; hypothesis
deafness,; sequences,; auditory; scaffolding; hypothesis
L-LIN/01 - GLOTTOLOGIA E LINGUISTICA
Italian
20-feb-2018
PSICOLOGIA, LINGUISTICA E NEUROSCIENZE COGNITIVE - 77R
30
2016/2017
open
(2018). Processing and learning of sequential patterns in deaf and hearing individuals: differences and similarities. (Tesi di dottorato, Università degli Studi di Milano-Bicocca, 2018).
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/199067
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