Date of Defense




First Advisor

Dr. R. Wayne Fuqua

Second Advisor

Dr. Douglas Woods

Third Advisor

Dr. Lester Wright Jr.


Thumb sucking and nail biting has been conceptualized by some in the field to be symptoms of underlying psychopathology. Although this theoretically derived notion has been widely accepted, some later researches found contradictory results. Due to these mixed results, the empirical status of the position remains unclear. An alternative way to conceptualize the development/maintenance of these behaviors is to determine their function. The purpose of this study was to determine the variable maintaining nervous habit behavior, such as thumb sucking and nail biting in children, through functional analysis. Study included 10 children, ages 5-11, who displayed chronic thumb sucking and nail biting. 3 sessions of functional analysis consisting of 8 conditions were ran for each child. A 4% criterion of intervals was selected to decide the function of the habit. The results of this study indicated that there are many different maintaining variables for the same behavior in children.

Access Setting

Honors Thesis-Campus Only