Neither Threat of Shock nor Acute Psychosocial Stress Affects Ambiguity Attitudes

Abstract

Decisions under uncertainty can be differentiated into two classes: risky, which has known probabilistic outcomes, and ambiguous, which has unknown probabilistic outcomes. Across a variety of types of decisions, people find ambiguity extremely aversive, subjectively more aversive than risk. It has been shown that the transient sympathetic arousal response to a choice predicts decisions under ambiguity but not risk, and that lifetime stress uniquely predicts attitudes toward ambiguity. Building on these findings, this study explored whether we could bias ambiguity and risk preferences with an arousal or acute stress manipulation that is incidental to the choice in two independent experiments. One experiment induced sympathetic arousal with an anticipatory threat paradigm, and the other manipulated incidental acute stress via a psychosocial stressor. The efficacy of the manipulations was confirmed via pupil dilation and salivary cortisol, respectively. Participants made choices between a guaranteed $5 option and a lottery with either a known (risky) or unknown (ambiguous) probabilistic outcome. Consistent with previous findings, participants were more averse to a given level of ambiguity than to a numerically equal level of risk. However, in contrast to our hypothesis, we found no evidence that transient arousal or acute stress that is incidental to the choice biases ambiguity preferences.

Resting-state heart rate variability (HRV) mediates the association between perceived chronic stress and ambiguity avoidance

“…Our results in a sample of healthy adults that exhibit various levels of perceived chronic stress support and replicate these findings. Our results are also supportive of previous findings that suggest that healthy adults typically would prefer to avoid uncertainty when probabilities are unknown (i.e., ambiguity) compared to uncertainty with known probabilities (i.e., risk) 32 – 36 . Uniquely in here, we assessed whether associations between perceived chronic stress and decision-making under uncertainty are dependent on the specific type of uncertain decisions of risk or ambiguity.…”

“…Results revealed that neither of these behavioral tendencies were directly related to the levels of chronic stress. This surprising result is somewhat in line with a recent study that found no effect of acute stress on behavioral attitudes towards risk and ambiguity 36 . Here, behavioral attitude towards ambiguity (i.e., ambiguity avoidance) was however positively correlated with resting-state HRV.…”

“…While both scenarios involve uncertainty, ambiguous and risky situations were shown to elicit different emotional, neural and physiological responses 29 – 31 . These differential responses, in turn, may also account for the clear behavioral differences in preference, such that the vast majority of healthy adults would prefer to avoid ambiguous situations compared to risky situations (i.e., ambiguity averseness), suggesting that ambiguity is viewed as more aversive compared to risk 32 – 36 .…”

“…A related subsequent question is whether physiological alterations in the form of reduced HRV play a role in these putative associations. In order to address these gaps in the literature, we implemented a decision-making task that involves separate risky and ambiguous trials, and used computational modelling to independently quantify individuals’ behavioral attitudes of approach and avoidance towards risk and ambiguity 30 , 36 , 37 . Ninety-two healthy adults with various levels of perceived chronic stress completed this task following a 5-min resting-state HRV recording.…”

Synchronized Incidental Affect Changes Ambiguity Preferences

“…The main difference between this task and previous iterations (FeldmanHall et al, 2016;Levy et al, 2010;Raio et al, 2022;Sambrano et al, 2022) was the use of an emotionally charged or neutral image as the occluder (see Fig. 1).…”