Abstract P430: Neuroimaging of Goal Directed Behavior in Overweight Women
Background: The purpose of this pilot study was to test the Dual System approach to health behavior change in forty non-diabetic midlife women, age 47-55 years recruited from an internal medicine clinic, as the basis for future health behavior change research. The Dual System is a novel approach for use in clinical interventions, and includes goal-directed and habit-based systems. Based on this paradigm, participants successful with goal-directed behavior are also more successful developing habitual health behaviors concurrently over time, and will have improved health outcomes.
Methods: Preliminary analysis compared the overweight (BMI 25-40 kg/m2) experimental group (n=10) and healthy weight (BMI 18.5-25 kg/m2) controls (n=13). All received instructions and a demonstration of the decision task outside the MRI scanner as well as written and verbal instructions inside the scanner. To assess performance, accuracy percentages on the task were calculated (correct responses divided by total number of responses x 100). The t-test was used to compare scores between groups on the decision task during training, outcome devaluation, and slips of action tasks.
Results: Preliminary results indicate no significant difference in training scores between the overweight group (7.6±1.5) and healthy weight controls (7.1±1.6) (t=.765; p=.45). Scores on the outcome devaluation task were higher in the overweight (6.3; ± 0.5) than the healthy weight group (5.3; ± 1.7), although the difference did not reach significance (t=1.75; p=.09). No difference in scores was found between the overweight group (6.7± 2.0) vs. controls (5.2 ± 2.3) (t=1.587; p=.12), indicating no deficit in goal directedness or overreliance on habits. Behavioral results were consistent with fMRI findings of greater activation in the bilateral middle frontal gyrus regions (associated with planning and self-regulation) in overweight compared to healthy weight women during the outcome devaluation task.
Conclusion: These preliminary findings have implications for the science of health behavior change. Overweight compared to healthy weight women were sensitive to goals, but had heightened self-regulation responses that indicate difficulty transforming goals into action. Future study is needed to test goal directed behavior as it relates to specific aspects of energy balance to guide interventions for long-term maintenance of physical activity, and to improve health outcomes.
- © 2013 by American Heart Association, Inc.