Graduation Date

Fall 12-20-2019

Document Type


Degree Name

Doctor of Philosophy (PhD)


Medical Sciences Interdepartmental Area

First Advisor

Wayne W. Fisher

Second Advisor

Brian D. Greer

Third Advisor

Keith D. Allen

Fourth Advisor

Mark D. Shriver


Multiple schedules are schedules of reinforcement that are often used to facilitate more manageable rates of a replacement behavior such as a communication response following functional communication training as an intervention for destructive behavior. Commonly, reinforcement schedule thinning involves multiple fading steps that can take more than 100 sessions to achieve therapeutic goals. The purpose of this experiment was to evaluate a method for rapidly achieving fading steps in a multiple schedule by including competing items during the extinction interval. Four children diagnosed with autism successfully reached the terminal extinction interval with a ≥80% reduction in problem behavior. Two of the four participants reached the terminal extinction interval during a systematic assessment to identify an appropriate initial extinction interval. This study produced two important findings. First, the inclusion of competing items successfully and rapidly achieved the terminal extinction interval in a multiple schedule. Second, a novel use of a systematic assessment procedure identified participants for whom the competing items were unnecessary to rapidly achieve the terminal extinction interval.


I would like to express my deepest gratitude to the grace and mercy of the members of my committee in supporting me through the long and arduous journey of developing of this manuscript. In particular, I am eternally grateful to the patience and unparalleled kindness of my mentor and advisor, Dr. Wayne Fisher. I wish to also acknowledge the friends and colleagues that helped me through this process: Valdeep Saini, Dan Mitteer, Ashley Fuhrman, Brian Greer, Courtney Smith, Terralyn Tiffer, Todd Owen, Stu Law, Mark Malady, Shane Spiker, Jake Lamphere, Ryan O’Donnell, Cameron Green, David Acevedo, Derrick Grime, Kendra Newsome, Donny Newsome, Tim Fuller, Tiffany Aninao, and Marisela Pallares. Finally, I could not have done this without the love and support of my family, specifically my mother Catherine Greenhouse, my aunt Lynn Greenhouse, and my wonderful wife, Lauren Brown.