Document Type

Dissertation

Degree

Doctor of Philosophy

Major

Psychology, Clinical-Community

Date of Defense

7-31-2008

Graduate Advisor

Brian Vandenberg, PhD

Committee

Elizabeth Kellogg

Bucur, Barbara

Greco, Laurie

Abstract

Over the past thirty years a consensus has emerged that the word reading difficulties of dyslexic readers stem from deficits in phonological processing. One experimental paradigm that has provided support for this view is the finding that dyslexic readers demonstrate deficits in word retrieval from long term memory on picture naming tasks. Dyslexic readers are able to retrieve fewer words in their receptive vocabularies and are less accurate than normally developing readers. However, the conclusion that dyslexic readers? difficulties in picture naming are the consequence of deficits in phonological processing is inferential. The current study uses the tip-of-the-tongue (TOT) paradigm to provide evidence that dyslexic readers demonstrate a specific deficit in the retrieval of phonological information from long term memory. Participants consisted of 16 dyslexic children and 31 control children, mean age of 115 months. Children were given a picture naming task consisting of 143 target words that varied in length and frequency of use. Results indicate that dyslexic children report more TOT experiences than control children. Moreover, when examined from the perspective of theoretical models of word retrieval, dyslexic children did not differ from control children in the percent of failures at the first step of word retrieval, the retrieval of semantic information. However, dyslexic children reported a significantly higher proportion of failures at the second step in word retrieval, the retrieval of phonological representations. This is one of the first studies to provide direct support that dyslexia is related to a specific deficit in phonological representation.

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Psychology Commons

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