The neural substrates of probabilistic and intertemporal decision making

Area of Science:

• Neuroscience
• Cognitive Psychology
• Decision Science

Background:

• Decision-making models often assume shared psychological processes for choices involving risk (probabilistic outcomes) and delay (intertemporal outcomes).
• Behavioral evidence supporting this hypothesis has been inconclusive, necessitating alternative investigation methods.
• Functional neuroimaging combined with behavioral data offers a potential avenue to differentiate these decision-making domains.

Purpose of the Study:

• To investigate whether risky choice and intertemporal choice engage distinct neural substrates.
• To identify specific brain regions associated with processing risk versus delay in monetary reward decisions.
• To explore the relationship between brain activation patterns and choice behavior in these domains.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed to monitor brain activity in participants.
• Participants made choices between pairs of real monetary rewards with varying levels of risk or delay.
• Behavioral data on choices made were collected and correlated with neuroimaging findings.

Main Results:

• Both risky and intertemporal choices activated brain systems associated with executive control.
• Risky choices showed greater activation in posterior parietal and lateral prefrontal cortices.
• Intertemporal choices demonstrated increased activation in the posterior cingulate cortex and striatum.
• Activation in reward evaluation regions predicted riskier choices, while control region activation predicted delayed or less-risky choices.

Conclusions:

• The study identified distinct patterns of brain activation for risky and intertemporal choices.
• These findings suggest that decisions involving risk and delay utilize at least partially distinct cognitive processes.
• Neuroimaging provides valuable insights into the neural underpinnings differentiating these fundamental aspects of decision making.