The successor representation subserves hierarchical abstraction for goal-directed behavior
Fig 9
Transition types with respect to preferred transitions.
Arrows colored by transition type with respect to the preferred and removed transitions as shown in Fig 1C. Here, preferred transitions are coded as orange (“preferred”) (blue arrows in Fig 1C). These can be the outcomes of selecting both <z> and <m> in their outgoing states. These transitions were included as nuisance regressors in our models, since we expect them to yield faster response times as they are more predictable. It can be seen that only the top node does not have any outgoing preferred transitions, and when referencing Fig 1B, it can be seen this is the only node with 4 possible immediate outcomes (2 distinct outcomes for each action). Hence, this node is referred to as “wide node” and transitions into this node are labeled as such (yellow). Transitions out of this node are labeled as “wide trans” (pink). Both these transitions can be expected to yield slower response times, since the more diffuse nature of transitions out of this node makes them harder to anticipate. Therefore, both these transition types are included as nuisance regressors in our models. It can be seen only one within-wing transition is not preferred and not associated with the wide node (blue, “within”). This transition can be contrasted with the “between” wing transition (green) to yield an unbiased estimate of higher-order surprise-based slowing.