SELF CONTROL AND MOTIVATION IN YOUNG ADULTS WITH VARYING LEVELS OF IMPULSIVITY: A DIMENSIONAL APPROACH

Abstract

The purpose of this research project is to better understand how self-control and motivation play a role in impulsive behavior as observed in AD/HD. Symptoms of impulsivity in AD/HD have been associated with poor self-control (e.g., Barkley, 1997, Willcutt, Pennington &Ozonoff, 2005), and also with an unusual sensitivity to rewards such as money (e.g., Douglas, 1999; Solanto et al., 2001, Sonuga-Barke et al., 2003). We know that self-control and motivation develop with age and play a key role in several clinical conditions involving poor impulse control, yet little is known about the interaction between these two fundamental processes. We are interested in studying these processes in interaction with one another and in relation to AD/HD symptoms. Neuropsychological studies reveal that executive function (EF) deficits do not fully explain AD/HD and its symptoms, as EF deficits have only accounted for less than 50% of the variance of AD/HD symptoms (Castellanos et al, 2006). While the impairment of response inhibition is the most reliable EF impairment in studies to date (Willcutt et al, 2005), motivation and reward processing deficits seem to coexist independent of these deficits (Luman, 2006, Sagvolden, 2006; Solanto et al., 2001). These findings have led researchers to develop the "dual pathway" hypothesis that incorporates both executive dysfunction of response inhibition as well as motivational deficits (Sonuga-Barke, 2002). The aim of this project is to further our understanding of how the interplay of these processes may be related to impulsivity and how they impact and result in certain "real world" behaviors. One interesting feature of this project is the development of new tasks that are capable of assessing both individual pathways ("topdown"/ executive function and "bottom-up"/motivation) and their interaction within the task itself. This lends not only to the strength of the design, but reflects the most current research trends in the field and makes a unique contribution as well.