Association for Behavior Analysis International

The Association for Behavior Analysis International® (ABAI) is a nonprofit membership organization with the mission to contribute to the well-being of society by developing, enhancing, and supporting the growth and vitality of the science of behavior analysis through research, education, and practice.


49th Annual Convention; Denver, CO; 2023

Event Details

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Invited Paper Session #248
CE Offered: BACB
A Behavioral Approach to the Treatment of Aphasia: Scratching the Surface
Sunday, May 28, 2023
5:00 PM–5:50 PM
Convention Center Four Seasons Ballroom 2/3
Area: VRB; Domain: Basic Research
Chair: Rocio Rosales (University of Massachusetts Lowell)
CE Instructor: Rocio Rosales, Ph.D.
Presenting Author: ZUILMA GABRIELA SIGURDARDOTTIR (University of Iceland)
Abstract: Aphasia is an adult language disorder that can be acquired following a cerebral vascular accident (e.g., stroke). There are many types of aphasia and it is common for patients to be diagnosed with one type of aphasia in the beginning but be diagnosed with a different type of aphasia during the healing period. Healing typically lasts for 6 to 18 months post trauma. After the healing period the condition becomes chronic. Broca´s aphasia, which I mostly focus on, is characterized by a diminished vocabulary and by the slow, broken, and labored formation of sentences. The processes that enable improvements in fluent speech, e.g., in naming, reading, sentence structure, etc., are not well understood. Various approaches have been used to treat patients with Broca´s aphasia including speech therapy. Most studies show improvements after treatment. Still, the development of an effective and efficient treatment, one that reliably works better than others for specific patients with specific symptoms, remains to be established. Treatment based on operant conditioning or stimulus control procedures seemed to be promising in the very limited number of available studies over 20 years ago. My curiosity with regard to Broca‘s aphasia, and my firm believe that the application of learning principles could alleviate some of those symptoms led me into experimenting with a behavioral treatment. It is my goal for today to present the data of these studies as an example of how learning principles can be applied systematically in the treatment of aphasia to increase fluent speech. These studies just scratched the surface and need to be continued. It was my intent to try out something that could potentially help a few patients achieve more fluent speech. Participants in these studies were adults with chronic-aphasia, aged 51-63. The performances that were treated varied across participants but all had to do with fluent speech, e.g., naming people or objects, making sentences, sequencing stimuli, discriminating written words or reading compound words. Treatment was based on stimulus control procedures like errorless learning, backward chaining, and other operant conditioning. They were treated for up to 7 months. Treatment variables were clearly defined and systematically used in standard ways across participants with flexibility for adaptation to individual outcomes using clearly defined criteria. Prompts that were used in training faded out as performances improved. Treatment effects were evaluated with single subject experimental designs. The performances of all participants improved significantly. Performances ultimately reached 100% correct in some tasks without any prompts from the experimenter. Generalization measures across stimuli and settings demonstrated that their improved performances generalized to novel stimuli and novel settings. One study was directly replicated. When a replication failed further studies were undertaken in an attempt to understand the reasons for the failure to replicate. Systematic replications are needed to assess generality of effects of this experimental treatment. Replication of therapeutic effects is a prerequisite for advancement in any therapeutic field. Only with direct and systematic replications of single-subject experimental studies is it possible to ultimately determine which type of therapy is effective for what type of patient with what type of etiology and symptoms and in which particular situation (Barlow & Hersen, 1984; Hayes, Barlow, & Nelson-Gray, 1999; Sidman, 1960).
Instruction Level: Basic
Target Audience:

All ABA practitioners

Learning Objectives: At the conclusion of the presentation, participants will be able to:(1) List the main symptoms of Broca‘s aphasia; (2) Describe an intervention based on errorless learning and performance feedback for symptoms of aphasia; (3) Discuss the benefits of applying the methods and strategies of applied behavior analysis in the treatment of aphasia.
Zuilma Gabriela Sigurðardóttir finished her BA in psychology in 1985 at the University of Iceland, her MA in Behavior Analysis and Therapy in 1989 at Southern Illinois University-Carbondale and her PhD in Psychology in 1992 at Northeastern University-Boston. She became member of ABAI in 1987. She has worked on the dissemination of behavior analysis in Iceland and Europe for 30 years. First as therapist, consultant, and adjunct faculty at the University of Iceland, while also being an administrator and developer of services for the disabled in Reykjavík. Then she became an administrator and developer of psychological services for schools at the compulsory level for the City of Reykjavík. She entered academia full time in 1999 as assistant professor of behavior analysis in the psychology department of the University of Iceland. She became associate professor in 2004 and full professor in 2018. She has taught behavior analysis at all levels, both required and elective courses that she established. She has guided and supervised approximately 190 students‘ research projects for thesis in behavior analysis at all levels, including the only PhD thesis in behavior analysis in Iceland so far. She has managed and coordinated graduate student practica in public schools for 23 years. She has aided Icelandic students to find programs of study in behavior analysis in the United States and Europe since 1998 and has guided them in the application process. She was department chair of the psychology department at the University of Iceland in 2003-2005. She was president of the European Association for Behavior Analysis in 2015-2017 and past-president in 2017-2020. Her research interests include the analysis of language acquisition from a stimulus equivalence paradigm and applied behavior analysis in various contexts. She has served as associate editor of EJOBA and JOBE for many years and was on the review board of EJOBA for many years prior to becoming associate editor. She has reviewed manuscripts for various other scientific journals like JEAB and for scientific journals in various other disciplines as well. She has served as reviewer of grant proposals for the Icelandic Research Council and other granting agencies. She was an exchange teacher at the University of Latvia with Erasmus fellowships in 2015-2019 and led the establishment of the Baltic Association for Behavior Analysis. She has continued teaching for Latvia through the internet in the last three years. She aided in coordinating the first conference on behavior analysis in Sofia, Bulgaria in 2016. She has taught re-education courses for elementary school teachers, psychologists, administrators, and allied health professionals in Iceland and Latvia. She has also offered behavior management classes to parents and teachers in Iceland in Icelandic, English, and Spanish. She has had a small private practice where she provides services to families. She presently serves as board chairman of the newly established Applied Behavior Analysis masters program at the University of Iceland. She enjoys travel and culture, classical music concerts, family gatherings, and her dog. She has two adult children and a grand-daughter on the way. She was born in Mexico City but moved from there at age 10 and settled down in Iceland at age 11 with her Mexican mother and Icelandic step father. She is the recipient of the SABA 2023 award for International Dissemination of Behavior Analysis.



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