Dopaminergic challenge dissociates learning from primary versus secondary sources of information
- University of Birmingham, United Kingdom
Abstract
Some theories of human cultural evolution posit that humans have social-specific learning mechanisms that are adaptive specialisations moulded by natural selection to cope with the pressures of group living. However, the existence of neurochemical pathways that are specialised for learning from social information and from individual experience is widely debated. Cognitive neuroscientific studies present mixed evidence for social-specific learning mechanisms: some studies find dissociable neural correlates for social and individual learning whereas others find the same brain areas and, dopamine-mediated, computations involved in both. Here we demonstrate that, like individual learning, social learning is modulated by the dopamine D2 receptor antagonist haloperidol when social information is the primary learning source, but not when it comprises a secondary, additional element. Two groups (total N = 43) completed a decision-making task which required primary learning, from own experience, and secondary learning from an additional source. For one group the primary source was social, and secondary was individual; for the other group this was reversed. Haloperidol affected primary learning irrespective of social/individual nature, with no effect on learning from the secondary source. Thus, we illustrate that dopaminergic mechanisms underpinning learning can be dissociated along a primary-secondary but not a social-individual axis. These results resolve conflict in the literature and support an expanding field showing that, rather than being specialised for particular inputs, neurochemical pathways in the human brain can process both social and non-social cues and arbitrate between the two depending upon which cue is primarily relevant for the task at hand.
Data availability
All raw data and analysis scripts can be accessed at the Open Science Framework data repository:https://osf.io/398w4/?view_only=08c062a9694a4b00ac7cbc52ee333628
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (Midlands Integrative Biosciences Training Partnership (MIBTP) Doctoral Funding)
- Alicia J Rybicki
H2020 European Research Council (757583 - Brain2Bee)
- Sophie L Sowden
- Bianca Schuster
- Jennifer L Cook
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Informed consent was obtained from each subject. The study was in line with the local ethical guidelines approved by the local ethics committee (ERN_18_1588) and in accordance with the Helsinki Declaration of 1975.
Copyright
© 2022, Rybicki 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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Dopaminergic challenge dissociates learning from primary versus secondary sources of information
eLife 11:e74893.
https://doi.org/10.7554/eLife.74893
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