INDIVIDUAL DIFFERENCES AND COGNITIVE BIAS IN DECISION TO TREAT UNRUPTURED BRAIN ANEURYSM

Purpose: At least since the research of Kahnemann (1979) and Tversky (1974), the impact of cognitive bias on decision making has been well established.  Indeed, the difference between veridical decision making (i.e, finding the correct response independent of situation or actor) is quite different from adaptive decision making (i.e., actor-centered and priority based decision making). However, the relative contribution of individual differences (e.g., intelligence, personality, etc.) as related to the impact of cognitive bias on decision making is relatively understudied.  These individual difference factors can effect both patient and clinician decision making and, unlike cognitive biases, can be measured with a high degree of accuracy.  For example, intelligence is measured with greater reliability than height or weight in a doctor’s office (Jensen, 1998, p. 50).  Thus, we hypothesize that simultaneous measurement of individual difference variables and cognitive biases represents a fruitful means by which potential interactions with optimal decision making might be better modeled.

Method: Intelligence was measured with the Wechsler Adult Intelligence Scale - Revision 3.  Personality variables included Neuroticism, Extraversion, Openness to Experience, Agreeableness, and Conscientiousness (Costa & McRae, 1992).  We asked subjects several questions designed to violate utility theory (e.g., Which of the following would you prefer: A) 50% chance to win $1000; 50% chance to win nothing, or B) $450 for sure?).  We also asked subjects hypothetical questions regarding a newly discovered unruptured cerebal aneurysm and their desire to operate or “watch and wait” given various risk/benefit utilities. 

Result: We report on a young (age range 18-29) cohort, free from psychiatric or neurological illness, described in several recent neuroimaging studies (Jung et al., 2009; Jung et al., 2010a; 2010b). Subjects ranged in intelligence from the low average (i.e., Full Scale Intelligence Quotient = 90) to Very Superior Range (i.e., Full Scale Intelligence Quotient = 145). Results support meaningful links between individual difference variables and cognitive biases relevant to decision making in treatment of unruptured cerebral aneurysm.

Conclusion: Individual difference measurement provides a meaningful method by which potential cognitive biases might be assessed and factored into decision making utility analyses at the level of the individual patient.  Future research will be necessary to determine if matching of individual difference characteristics and potential cognitive biases to decision making serves to optimize treatment outcomes.