Model D

[Petter]

https://www.sciencedirect.com/scienc...74742713002633

This article considers two recent lines of research concerned with the construction of imagined or simulated events that can provide insight into the relationship between memory and decision making. One line of research concerns episodic future thinking, which involves simulating episodes that might occur in one’s personal future, and the other concerns episodic counterfactual thinking, which involves simulating episodes that could have happened in one’s personal past. We first review neuroimaging studies that have examined the neural underpinnings of episodic future thinking and episodic counterfactual thinking. We argue that these studies have revealed that the two forms of episodic simulation engage a common core network including medial parietal, prefrontal, and temporal regions that also supports episodic memory. We also note that neuroimaging studies have documented neural differences between episodic future thinking and episodic counterfactual thinking, including differences in hippocampal responses. We next consider behavioral studies that have delineated both similarities and differences between the two kinds of episodic simulation. The evidence indicates that episodic future and counterfactual thinking are characterized by similarly reduced levels of specific detail compared with episodic memory, but that the effects of repeatedly imagining a possible experience have sharply contrasting effects on the perceived plausibility of those events during episodic future thinking versus episodic counterfactual thinking. Finally, we conclude by discussing the functional consequences of future and counterfactual simulations for decisions.

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12. episodic memory vs. episodic simulation

[Petter]

https://www.frontiersin.org/articles...019.00028/full

FIGURE 1. Characteristics of the shift from goal-directed to habitual behavior. (A) Left: Goal-directed and habitual behaviors are competitive processes that act in balance. Goal-directed behavior is characterized by a high requirement for attention, is highly contingent on present reward value, and demonstrates flexibility of responding. Habitual behavior is stimulus-driven, less dependent on present reward value, and governed by behavioral automaticity. Right: Addiction/compulsion represents an extreme state of habit. (B) The transition from goal-directed behavior to habitual behavior and then into compulsion, or addiction is graded. Shift from goal-directed to habitual behavior and then to compulsion/addiction corresponds to strengthened stimulus-response association and reduced action-outcome contingency. These processes are bidirectional, i.e., a behavior can shift on the spectrum from goal-directed to habitual performance, and back again—though in the extremes of addiction whether it is possible to return fully to habit/goal-directed states is less clear. (C) During instrumental training, rates of responding for a reward increase. Post-training reward devaluation reduces response rates more quickly for goal-directed behaviors than it does for habitual behaviors, which take many more extinction trials to fully dissipate. The extremes of addiction are characterized by compulsive responding that is resistant even to punishment. (D) The balance between goal-directed and habitual behavioral states corresponds to relative levels of neural activity in the dorsomedial (DMS) vs. dorsolateral (DLS) striatum. (E) Task-bracketing activity pattern emerges in the DLS as animals are over-trained on a rewarded behavioral sequence (e.g., running a T-maze for a tasty reward). Spiny Projection Neurons (SPNs) exhibit high activity at the beginning of a learned motor sequence and again at the end as the animal approaches the reward. Fast-spiking interneurons (FSIs) exhibit high activity during the middle stages of a behavioral sequence.

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