Intrinsic connectivity between the hippocampus, nucleus accumbens, and ventral tegmental area in humans
Article first published online: 5 NOV 2012
Copyright © 2012 Wiley Periodicals, Inc.
Volume 23, Issue 3, pages 187–192, March 2013
How to Cite
Kahn, I. and Shohamy, D. (2013), Intrinsic connectivity between the hippocampus, nucleus accumbens, and ventral tegmental area in humans. Hippocampus, 23: 187–192. doi: 10.1002/hipo.22077
- Issue published online: 27 FEB 2013
- Article first published online: 5 NOV 2012
- Manuscript Accepted: 30 AUG 2012
- Rappaport Institute (I.K.)
- NIDA. Grant Number: R03 DA026957 (D.S.)
- NSF Career Development Award (D.S.)
- functional imaging
Recent studies suggest that memory formation in the hippocampus is modulated by the motivational significance of events, allowing past experience to adaptively guide behavior. The effects of motivation on memory are thought to depend on interactions between the hippocampus, the ventral tegmental area (VTA), and the nucleus accumbens (NAcc). Indeed, animal studies reveal anatomical pathways for circuit-level interaction between these regions. However, a homologue circuit connectivity in humans remains to be shown. We characterized this circuitry in humans by exploiting spontaneous low-frequency modulations in the fMRI signal (termed resting-state functional connectivity), which are thought to reflect functionally related regions and their organization into functional networks in the brain. We examined connectivity in this network across two datasets (hi-resolution, n = 100; standard resolution, n = 894). Results reveal convergent connectivity between the hippocampus, and both the NAcc and the VTA centered on ventral regions in the body of the hippocampus. Additionally, we found individual differences in the strength of connectivity within this network. Together, these results provide a novel task-independent characterization of circuitry underlying interactions between the hippocampus, NAcc, and VTA and provide a framework with which to understand how connectivity might reflect and constrain the effects of motivation on memory. © 2012 Wiley Periodicals, Inc.