Intrinsic monitoring of learning success facilitates memory encoding via the activation of the SN/VTA-Hippocampal loop

Elife. 2016 Sep 20;5:e17441. doi: 10.7554/eLife.17441.

Abstract

Humans constantly learn in the absence of explicit rewards. However, the neurobiological mechanisms supporting this type of internally-guided learning (without explicit feedback) are still unclear. Here, participants who completed a task in which no external reward/feedback was provided, exhibited enhanced fMRI-signals within the dopaminergic midbrain, hippocampus, and ventral striatum (the SN/VTA-Hippocampal loop) when successfully grasping the meaning of new-words. Importantly, new-words that were better remembered showed increased activation and enhanced functional connectivity between the midbrain, hippocampus, and ventral striatum. Moreover, enhanced emotion-related physiological measures and subjective pleasantness ratings during encoding were associated with remembered new-words after 24 hr. Furthermore, increased subjective pleasantness ratings were also related to new-words remembered after seven days. These results suggest that intrinsic-potentially reward-related-signals, triggered by self-monitoring of correct performance, can promote the storage of new information into long-term memory through the activation of the SN/VTA-Hippocampal loop, possibly via dopaminergic modulation of the midbrain.

Keywords: SN/VTA-Hippocampal loop; dopamine; fMRI; human; memory; neuroscience; reward; word learning.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Female
  • Hippocampus / physiology*
  • Humans
  • Learning*
  • Magnetic Resonance Imaging
  • Male
  • Memory*
  • Mesencephalon / physiology*
  • Ventral Striatum / physiology*
  • Young Adult

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.