In the proposed project, we examine the effects of model based semantic treatment on improving lexical access defects in aphasia. We plan to build on previous work highlighting the role of theories of lexical processing in improving lexical access. In the proposed project, we plan to establish a data set of treatment methods for lexical access deficits that include oral confrontation naming and category fluency. All our treatment methods are focused on maximizing generalization to untrained semantically related items within the semantic category. Our treatment approach for lexical access deficits that utilizes the semantic complexity hypothesis. We define semantic complexity within a category in terms of: a) lesser degree of overlap between the item and prototype; b) greater variation of semantic features; and c) hierarchically greater distance between the prototype and item in a multidimensional space. Our previous work has demonstrated that training the more complex atypical examples of animate categories results in generalization to the less complex typical examples in aphasic patients with naming deficits. In this project, we plan to further build this hypothesis and demonstrate the effects of complexity on typicality for a variety of categories such as inanimate categories, well defined categories and ad hoc categories. We also extend our investigations to understand the mechanisms underlying the relationship between typicality and complexity in normal and brain damaged individuals. We will accomplish this through online category verification tasks across different types of semantic categories.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Small Research Grants (R03)
Project #
5R03DC006359-02
Application #
6784081
Study Section
Special Emphasis Panel (ZDC1-SRB-O (30))
Program Officer
Cooper, Judith
Project Start
2003-08-01
Project End
2006-07-31
Budget Start
2004-08-01
Budget End
2005-07-31
Support Year
2
Fiscal Year
2004
Total Cost
$72,000
Indirect Cost
Name
University of Texas Austin
Department
Other Health Professions
Type
Other Domestic Higher Education
DUNS #
170230239
City
Austin
State
TX
Country
United States
Zip Code
78712
Sandberg, Chaleece; Sebastian, Rajani; Kiran, Swathi (2012) Typicality mediates performance during category verification in both ad-hoc and well-defined categories. J Commun Disord 45:69-83
Kiran, Swathi; Sandberg, Chaleece; Sebastian, Rajani (2011) Treatment of category generation and retrieval in aphasia: effect of typicality of category items. J Speech Lang Hear Res 54:1101-17
Kiran, Swathi; Sandberg, Chaleece; Abbott, Karen (2009) Treatment for lexical retrieval using abstract and concrete words in persons with aphasia: Effect of complexity. Aphasiology 23:835-853
Edmonds, Lisa A; Nadeau, Stephen E; Kiran, Swathi (2009) Effect of Verb Network Strengthening Treatment (VNeST) on Lexical Retrieval of Content Words in Sentences in Persons with Aphasia. Aphasiology 23:402-424
Kiran, Swathi (2008) Typicality of inanimate category exemplars in aphasia treatment: further evidence for semantic complexity. J Speech Lang Hear Res 51:1550-68
Kiran, Swathi; Bassetto, Gina (2008) Evaluating the effectiveness of semantic-based treatment for naming deficits in aphasia: what works? Semin Speech Lang 29:71-82
Kiran, Swathi; Johnson, Lauren (2008) Semantic complexity in treatment of naming deficits in aphasia: evidence from well-defined categories. Am J Speech Lang Pathol 17:389-400
Kiran, Swathi (2007) Complexity in the treatment of naming deficits. Am J Speech Lang Pathol 16:18-29