Absent Optimism Bias in Updating Beliefs about Future Life Events in Adults with High-Functioning Autism

Background:  

People update their beliefs about their own future outcomes in an optimistically biased way because they tend to neglect undesirable new information. Theoretical explanations of this bias assume that motivational mechanisms related to the pleasure of having positive future outlooks interact with and guide cognitive mechanisms such as egocentric and confirmatory thinking. In adults with high functioning autism (HFA), however, the motivational-affective influences on decision making are diminished as evident in their rule-based reasoning in response to social cues, as well as in response to emotional framings of risky gambling options.

Objectives:  

Is this enhanced logical consistency in HFA also present in updating beliefs about future outcomes?

Methods:  

Adults with HFA (n = 20, 4 females, mean age 41.5 years; F84.0 and F48.5 with an at least average IQ) and typically developing controls (n = 20; 2 females, mean age 38.9 years) matched on age, gender, years of education and IQ were recruited. Diagnoses were established within a systematic assessment in a specialized outpatient clinic by two independent psychiatrists and in consideration of an extensive neuropsychological profile of the person concerned.

In the update experiment, participants estimated the probability of an adverse future event to occur in the lifetime. Next, they were presented with the official base rate of the respective event and were then given the opportunity to make a second estimation and to adjust their first estimate to this new information. Estimations were made for 44 different adverse events, concerned either oneself or a similar other, and were confronted with either desirable (i.e., lower than the first estimate) or undesirable (i.e., higher than the first estimate) base rates. Unbeknownst to participants, presented base rates were manipulated in order to control for the size of estimation errors calling for belief updates across the four experimental conditions (self_desirable base rates, self_undesirable base rates, other_desirable base rates, other_undesirable base rates).

Results:  

The optimism bias was replicated in the control group as updates (differences between the first and the second estimate) after undesirable base rates were significantly smallerthan updates after desirable base rates, and this effect was present exclusively in self-related judgments. However, in the HFA group, there were no significant differences in update sizes dependent on the desirability of the new information, neither in self- nor in other-related judgments.

Conclusions:  

In contrast to typically developing controls, adults with HFA did not show an optimistically biased updating of beliefs about their own or others’ future. This indicates an increased logical consistency in HFA in general prospective thinking which may be explained by diminished motivational-affective influences on decision making. Future research would need to investigate the benefits and disadvantages of the increased logical consistency in HFA for different domains such as professional and private decision making and affective state.