Intelligence moderates neural responses to monetary reward and punishment

Abstract

Hawes DR, DeYoung CG, Gray JR, Rustichini A. Intelligence moderates neural responses to monetary reward and punishment. J Neurophysiol 111: 1823-1832, 2014. First published February 12, 2014 doi:10.1152/jn.00393.2013The relations between intelligence (IQ) and neural responses to monetary gains and losses were investigated in a simple decision task. In 94 healthy adults, typical responses of striatal blood oxygen level-dependent (BOLD) signal after monetary reward and punishment were weaker for subjects with higher IQ. IQ-moderated differential responses to gains and losses were also found for regions in the medial prefrontal cortex, posterior cingulate cortex, and left inferior frontal cortex. These regions have previously been identified with the subjective utility of monetary outcomes. Analysis of subjects' behavior revealed a correlation between IQ and the extent to which choices were related to experienced decision outcomes in preceding trials. Specifically, higher IQ predicted behavior to be more strongly correlated with an extended period of previously experienced decision outcomes, whereas lower IQ predicted behavior to be correlated exclusively to the most recent decision outcomes. We link these behavioral and imaging findings to a theoretical model capable of describing a role for intelligence during the evaluation of rewards generated by unknown probabilistic processes. Our results demonstrate neural differences in how people of different intelligence respond to experienced monetary rewards and punishments. Our theoretical discussion offers a functional description for how these individual differences may be linked to choice behavior. Together, our results and model support the hypothesis that observed correlations between intelligence and preferences may be rooted in the way decision outcomes are experienced ex post, rather than deriving exclusively from how choices are evaluated ex ante.

Subcortical intelligence: Caudate volume predicts IQ in healthy adults

“…A correlation between caudate size and intelligence is well situated in literature that supports a role for the caudate in learning, particularly in relation to the prediction-error learning signal that is transmitted by dopamine [Bromberg-Martin et al, 2010;Cools et al, 2008;Hawes et al, 2014]. Nonetheless, a limitation of the present findings is that they are purely correlational and provide no evidence regarding a mechanism for the influence of caudate volume on intelligence.…”

Intelligence and Extraversion in the neural evaluation of delayed rewards

“…Of particular relevance to the present study, one fMRI study found that neural activity in the lateral PFC during a working memory task predicted both TD and intelligence assessed outside the scanner . Further, IQ has been linked to both the functional reward response and the anatomical volume of the caudate nucleus in the striatum (Grazioplene et al, 2015;Hawes et al, 2014). The association of IQ with the caudate may reflect that Intelligence modulates how prediction-error signals in this region respond to the perceived statistical features of the environment, given that higher intelligence is likely to afford enhanced evaluation of the context of reward.…”

Suboptimal Dishonesty: Rationality in the Absence of Strategic Behavior in Honesty Experiments

“…This may also contribute to the higher mean response times seen in the "ambiguous" group compared with both the "honest" and "dishonest" groups in both the win and loss trials, as well as the slower reaction times observed during dishonest behavior (Abe and Greene, 2014). Also, in a result from Hawes et al (2014), subjects with higher IQ exhibited weaker striatal BOLD signals after the reward was received, which is not inconsistent with the results in Abe and Greene (2014). This shows that sophistication has a role in the biology of decision-making (Coricelli and Nagel, 2009).…”

“…There is recent evidence suggesting that subjects with higher IQ base their decisions in a current trial on a greater number of past trials than subjects with low IQ (Hawes et al, 2014). Those who wish to strategically underreport their accuracy on trials with low-value outcomes would require the sophistication of basing their decisions on a great number of trials.…”

“…Those who wish to strategically underreport their accuracy on trials with low-value outcomes would require the sophistication of basing their decisions on a great number of trials. Since they are more likely to have high IQ (Hawes et al, 2014), and high IQ translates-at least theoretically-to dishonest actions in this game, the "ambiguous" group may exhibit the "strategic underreporting" that was shown to not occur in the "honest" group (Abe and Greene, 2014). This may also contribute to the higher mean response times seen in the "ambiguous" group compared with both the "honest" and "dishonest" groups in both the win and loss trials, as well as the slower reaction times observed during dishonest behavior (Abe and Greene, 2014).…”