1. Rigid reduced successor representation as a potential mechanism for addiction
- Author
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Kanji Shimomura, Ayaka Kato, and Kenji Morita
- Subjects
Value (ethics) ,Successor cardinal ,Research Report ,Punishment (psychology) ,media_common.quotation_subject ,Temptation ,03 medical and health sciences ,reward prediction error ,0302 clinical medicine ,Reward ,Reinforcement learning ,Humans ,habit ,030304 developmental biology ,media_common ,0303 health sciences ,Motivation ,Mechanism (biology) ,General Neuroscience ,Addiction ,Representation (systemics) ,spiral striatum‐midbrain circuit ,Corpus Striatum ,Clinical and Translational Neuroscience ,addiction ,Erratum ,dopamine ,Psychology ,Reinforcement, Psychology ,030217 neurology & neurosurgery ,Cognitive psychology - Abstract
Difficulty in cessation of drinking, smoking, or gambling has been widely recognized. Conventional theories proposed relative dominance of habitual over goal‐directed control, but human studies have not convincingly supported them. Referring to the recently suggested “successor representation (SR)” of states that enables partially goal‐directed control, we propose a dopamine‐related mechanism that makes resistance to habitual reward‐obtaining particularly difficult. We considered that long‐standing behavior towards a certain reward without resisting temptation can (but not always) lead to a formation of rigid dimension‐reduced SR based on the goal state, which cannot be updated. Then, in our model assuming such rigid reduced SR, whereas no reward prediction error (RPE) is generated at the goal while no resistance is made, a sustained large positive RPE is generated upon goal reaching once the person starts resisting temptation. Such sustained RPE is somewhat similar to the hypothesized sustained fictitious RPE caused by drug‐induced dopamine. In contrast, if rigid reduced SR is not formed and states are represented individually as in simple reinforcement learning models, no sustained RPE is generated at the goal. Formation of rigid reduced SR also attenuates the resistance‐dependent decrease in the value of the cue for behavior, makes subsequent introduction of punishment after the goal ineffective, and potentially enhances the propensity of nonresistance through the influence of RPEs via the spiral striatum‐midbrain circuit. These results suggest that formation of rigid reduced SR makes cessation of habitual reward‐obtaining particularly difficult and can thus be a mechanism for addiction, common to substance and nonsubstance reward., Long‐standing behavior towards a certain reward can lead to a formation of rigid reduced successor representation (SR) of states based on the future occupancy of the rewarded goal state. If it is formed, whereas no reward prediction error (RPE) is generated at the goal while the person does not resist temptation, once the person starts resistance, a sustained large RPE is generated at the goal, somewhat similarly to the hypothesized sustained fictitious RPE caused by drug‐induced dopamine.
- Published
- 2021