Intrinsically regulated learning is modulated by synaptic dopamine signaling
- New York University, United States
- L'Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Spain
- McGill University, Canada
- Universitat Autònoma de Barcelona, Spain
- Otto-von-Guericke University, Germany
- Sant Pau Institute of Biomedical Research, Spain
Abstract
We recently provided evidence that an intrinsic reward-related signal-triggered by successful learning in absence of any external feedback-modulated the entrance of new information into long-term memory via the activation of the dopaminergic midbrain, hippocampus, and ventral striatum (the SN/VTA-Hippocampal loop; Ripollés et al., 2016). Here, we used a double-blind, within-subject randomized pharmacological intervention to test whether this learning process is indeed dopamine-dependent. A group of healthy individuals completed three behavioural sessions of a language-learning task after the intake of different pharmacological treatments: a dopaminergic precursor, a dopamine receptor antagonist or a placebo. Results show that the pharmacological intervention modulated behavioral measures of both learning and pleasantness, inducing memory benefits after 24 hours only for those participants with a high sensitivity to reward. These results provide causal evidence for a dopamine-dependent mechanism instrumental in intrinsically regulated learning and further suggest that subject-specific reward sensitivity drastically alters learning success.
Data availability
Data is available via Dryad (https://dx.doi.org/10.5061/dryad.g5f7v1j)
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Data from: Intrinsically regulated learning is modulated by synaptic dopamine signalingAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Funding
Ministerio de Industria, Economía y Competitividad (PSI2011-29219)
- Antoni Rodriguez-Fornells
Ministerio de Industria, Economía y Competitividad (AP2010-4179)
- Pablo Ripollés
Morelly-Rotary Postdoctoral Fellowship
- Laura Ferreri
Ministerio de Sanidad, Servicios Sociales e Igualdad (CP04/00 121)
- Marta Valle
Deutsche Forschungsgemeinschaft (DFG-SFB-779/A15)
- Toemme Noesselt
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: This study was performed according to local ethics and to the Declaration of Helsinki. It was approved by the Ethics Committee of Hospital Sant Pau and by the Spanish Medicines and Medical Devices Agency (EudraCT 2016-000801-35). All participants gave informed written consent and received compensation for their participation in the study according to Spanish legislation.
Copyright
© 2018, Ripollés et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Intrinsically regulated learning is modulated by synaptic dopamine signaling
eLife 7:e38113.
https://doi.org/10.7554/eLife.38113
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