Word-Retrieval Treatment for Aphasia: Semantic Feature Analysis
Condition: Aphasia; Language Disorders; Speech Disorders
MeSH terms: Aphasia; Language Disorders; Speech Disorders
Study type: Interventional

Summary: 
      The purpose of this investigation is to further develop and test a treatment for word-finding
      problems in aphasia. The treatment is designed to strengthen meaning associations within
      categories of words (e.g., animals, tools, fruits). The treatment is also designed to be used
      as a search strategy in instances of word-finding difficulty. The study was devised to
      evaluate the extent to which treatment increases the ability to recall trained, as well as
      untrained, words.
    

Detailed description: 
      The purpose of the proposed research is to examine the effects of a semantically-oriented
      treatment on word retrieval in persons with aphasia. The planned investigations are designed
      to further the development of semantic feature training so that it may serve as not only a
      mechanism for improving disrupted lexical semantic processing, but also as a compensatory
      strategy during word retrieval failures. The proposed research will also address the issue of
      exemplar typicality (Kiran & Thompson, 2003) by examining the effects of training typical
      versus atypical exemplars of various categories with individuals with different types of
      aphasia. A series of 24 single subject experimental designs will be conducted in the context
      of a group design to address the following experimental questions:

        -  Will training atypical examples of living and artifact noun categories using semantic
           feature training result in a significantly different outcome* than training typical
           examples of living and artifact noun categories?

        -  Will training of one category of nouns using semantic feature training result in
           improved retrieval of untrained categories of nouns?

        -  Will effects of semantic feature training vary across aphasia types?

        -  Will semantic feature training result in increased production of content during
           discourse?

        -  Will generalization to untrained typical examples vary across generalization lists that
           are repeatedly exposed and those that are limited in exposure? (i.e., Does repeated
           exposure appear to contribute to generalization?)

             -  Outcome measure will reflect acquisition, response generalization within category,
                and response generalization across category effects of treatment.
    

Intervention name(s): Semantic Feature Analysis (SFA)Training
Intervention type(s): Behavioral
Intervention description(s): SFA entails having the speech-language pathologist (SLP) guide the participant through generation of pertinent semantic features for pictured treatment items (e.g., category membership, physical description, location of item in context, personal associations, action associated with item). For some participants, treatment items were grouped according to typicality of category membership (e.g,, a robin-typical bird and penguin-atypical bird). Training of atypical items may stimulate a broader semantic activation of the category and thus, may promote greater generalization. Treatment was applied sequentially to sets of items in the context of single-subject, multiple baseline designs. In this way, replication of treatment effects could be evaluated within and across participants. Treatment was administered by certified SLPs three times per week until prescribed accuracy levels were met during nontreatment probes or a maximum number of treatment sessions was completed.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Aphasia; Language therapy; Rehabilitation of speech and language disorders; Speech-language pathology