Persistent impact of prior experience on spatial learning.

Abstract

Learning to solve a new problem involves identifying the operating rules, which can be accelerated if known rules generalize in the new context. We ask how prior experience affects learning a new rule that is distinct from known rules. We examined how rats learned a new spatial navigation task after having previously learned tasks with different navigation rules. The new task differed from the previous tasks in spatial layout and navigation rule. We found that experience history did not impact overall performance. However, by examining navigation choice sequences in the new task, we found experience-dependent differences in exploration patterns during early stages of learning, as well as differences in the types of errors made during stable performance. The differences were consistent with the animals adopting experience-dependent memory strategies to discover and implement the new rule. Our results indicate prior experience shapes the strategies for solving novel problems, and the impact of prior experience remains persistent.Significance Statement Prior experience can be useful for solving new problems, especially when learned rules can generalize to new settings. However, it is unclear how prior experience impacts the strategies for learning new rules. We show that prior experience changes the strategies used to solve new problems without changing performance outcomes. The effects of prior experience remained after learning, when performance has plateaued. Our results suggest prior experience has a persistent impact on future problem solving, and may determine how distinct neural processes are engaged to solve new problems.