Article

Separate Valuation Subsystems for Delay and Effort Decision Costs

Cognitive Neuroscience Center, Centre National de la Recherche Scientifique, Unité mixte de recherche 5229, Reward and Decision Making Team, 69675 Bron, France.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 10/2010; 30(42):14080-90. DOI: 10.1523/JNEUROSCI.2752-10.2010
Source: PubMed

ABSTRACT

Decision making consists of choosing among available options on the basis of a valuation of their potential costs and benefits. Most theoretical models of decision making in behavioral economics, psychology, and computer science propose that the desirability of outcomes expected from alternative options can be quantified by utility functions. These utility functions allow a decision maker to assign subjective values to each option under consideration by weighting the likely benefits and costs resulting from an action and to select the one with the highest subjective value. Here, we used model-based neuroimaging to test whether the human brain uses separate valuation systems for rewards (erotic stimuli) associated with different types of costs, namely, delay and effort. We show that humans devalue rewards associated with physical effort in a strikingly similar fashion to those they devalue that are associated with delays, and that a single computational model derived from economics theory can account for the behavior observed in both delay discounting and effort discounting. However, our neuroimaging data reveal that the human brain uses distinct valuation subsystems for different types of costs, reflecting in opposite fashion delayed reward and future energetic expenses. The ventral striatum and the ventromedial prefrontal cortex represent the increasing subjective value of delayed rewards, whereas a distinct network, composed of the anterior cingulate cortex and the anterior insula, represent the decreasing value of the effortful option, coding the expected expense of energy. Together, these data demonstrate that the valuation processes underlying different types of costs can be fractionated at the cerebral level.

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    • "Human studies mirror these effects, indicating that individual differences in dopamine release predict willingness to expend effort for high value rewards and that amphetamine administration increases effortful behavior (Treadway et al., 2012; Wardle et al., 2011). Anterior cingulate cortex (ACC) structure and function also predicts effort-cost computation in animal and human studies, potentially via interactions with the dopamine system (Croxson et al., 2009; Endepols et al., 2010; Prevost et al., 2010; Walton et al., 2002; Walton et al., 2009). There are several reasons to expect that SZ patients would display abnormalities in effort-cost computation, including structural and "
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    • "negative variation; CRN, cue-related negativity; DRL, Driven Right Leg; EEG, electroencephalography ; ERN, error-related negativity; ERP, event-related potential; FRN, feedback-related negativity; RM-ANOVA, repeated measures analysis of variance; SCP, statistical cluster plot; UDTR, up-down transformed-rule. Neuroscience 273 (2014) 100–117 and anterior cingulate cortex have been implicated in task monitoring when participants made errors while bidding for rewards (Hare et al., 2008), when participants evaluate task effort needed to obtain primary rewards (Prevost et al., 2010), and when evaluating conflict between high-risk or low-risk choices (Kuhnen and Knutson, 2005). Neuroimaging, however, is not ideal for examining the interaction of processes that may occur over very fast timescales. "
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