Beta-Blocker Propranolol Modulates Decision Urgency During Sequential Information Gathering

Abstract

Arbitrating between timely choice and extended information gathering is critical for effective decision making. Aberrant information gathering behavior is thought to be a feature of psychiatric disorders such as schizophrenia and obsessive-compulsive disorder, but we know little about the underlying neurocognitive control mechanisms. In a double-blind, placebo-controlled drug study involving 60 healthy human subjects (30 female), we examined the effects of noradrenaline and dopamine antagonism on information gathering during performance of an information sampling task. We show that modulating noradrenaline function with 40 mg of the β-blocker propranolol leads to decreased information gathering behavior. Modulating dopamine function via a single dose of 400 mg of amisulpride revealed some effects that were intermediate between those of propranolol and placebo. Using a Bayesian computational model, we show that sampling behavior is best explained by inclusion of a nonlinear urgency signal that promotes commitment to an early decision. Noradrenaline blockade promotes the expression of this decision-related urgency signal during information gathering. We discuss the findings with respect to psychopathological conditions that are linked to aberrant information gathering.SIGNIFICANCE STATEMENT Knowing when to stop gathering information and commit to a choice option is nontrivial. This is an important element in arbitrating between information gain and energy conservation. In this double-blind, placebo-controlled drug study, we investigated the role of catecholamines noradrenaline and dopamine on sequential information gathering. We found that blockade of noradrenaline led to a decrease in information gathering. Dopamine blockade showed an intermediate, but nonsignificant, effect. Using a Bayesian computational model, we show that this noradrenaline effect is driven by increased decision urgency, a signal that reflects an escalating subjective cost of sampling. The observation that noradrenaline modulates decision urgency suggests new avenues for treating patients that show information gathering deficits.

Distinct Roles of Dopamine and Noradrenaline in Incidental Memory

“…Because of distinct pharmacokinetics, and to conform with previously used drug protocols (Silver et al, 2004; Gibbs et al, 2007; De Martino et al, 2008; Kahnt et al, 2015; Hauser et al, 2017, 2018; Kahnt and Tobler, 2017), we administered these drugs at two separate time points (Fig. 1 a ).…”

“…The groups were matched (Table 1) in terms of age, intellectual abilities (Wechsler, 1999), and mood at task onset (PANAS; Watson et al, 1988). Data from different tasks performed on the same subjects have been reported previously (Hauser et al, 2017, 2018). The study was approved by UCL research ethics and all subjects provided written informed consent.…”

Choice boosts curiosity

“…In addition, the noradrenaline system might play a modulatory role, given its implication in engagement or arousal, which is likely enhanced in conditions of increased autonomy (Howells et al, 2010;Sara & Bouret, 2012;Varazzani et al, 2015). A role for noradrenaline in information seeking is also supported by recent evidence indicating that pharmacological blockade of noradrenergic receptor stimulation with propranolol decreased information gathering in a task requiring participants to uncover cards until they felt confident to make a guess about the predominant underlying colour (Hauser et al, 2018). Hence, the increased autonomy experienced in the choice trials of our task may have contributed to implicate the noradrenergic system as mentioned above.…”

Advancing rational analysis to the algorithmic level

“…Such cost estimates could possibly assist in the development of tailored cognitive interventions. As a concrete example, multiple lines of evidence link the representation of time-based costs to an operation of specific catecholaminergic neuromodulators (Constantino et al 2017;Hauser et al 2018). This implies that dysregulated cognitive processing caused by irregular time-based costing could be amenable to pharmacological modulation.…”