From the introduction of Falk et. al. :
...according to the World Health Organization, “60% to 85% of people in the world—from both developed and developing countries—lead sedentary lifestyles”...self-relevant health messages can be perceived to be threatening to self-worth and are often met with resistance...Affirmation of core values (self-affirmation) preceding potentially threatening messages can reduce resistance and increase intervention effectiveness Therefore, one way to increase receptivity to messages discouraging sedentary behavior among sedentary individuals may be to affirm their core values in unrelated domains before exposure to the messages.
We focused on the brain’s ventromedial prefrontal cortex (VMPFC) during exposure to potentially threatening health messages emphasizing the need to be more active and less sedentary in a group of sedentary adults. VMPFC is the most common region implicated in self-related processing and is also a key region, along with the ventral striatum, implicated in positive valuation of stimuli.Their abstract:
Health communications can be an effective way to increase positive health behaviors and decrease negative health behaviors; however, those at highest risk are often most defensive and least open to such messages. For example, increasing physical activity among sedentary individuals affects a wide range of important mental and physical health outcomes, but has proven a challenging task. Affirming core values (i.e., self-affirmation) before message exposure is a psychological technique that can increase the effectiveness of a wide range of interventions in health and other domains; however, the neural mechanisms of affirmation’s effects have not been studied. We used functional magnetic resonance imaging (fMRI) to examine neural processes associated with affirmation effects during exposure to potentially threatening health messages. We focused on an a priori defined region of interest (ROI) in ventromedial prefrontal cortex (VMPFC), a brain region selected for its association with self-related processing and positive valuation. Consistent with our hypotheses, those in the self-affirmation condition produced more activity in VMPFC during exposure to health messages and went on to increase their objectively measured activity levels more. These findings suggest that affirmation of core values may exert its effects by allowing at-risk individuals to see the self-relevance and value in otherwise-threatening messages.
(A) VMPFC ROI. (B) Participants who showed higher levels of VMPFC activity during exposure to health messages subsequently decreased their sedentary behavior more in the month following the scan, controlling for baseline sedentary behavior and demographics.
