Centre for Human Brain Health, School of Psychology, University of Birmingham, Birmingham, United Kingdom.
Elife. 2022 Mar 15;11:e74893. doi: 10.7554/eLife.74893.
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 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.
一些人类文化进化理论假设，人类具有特定于社会的学习机制，这些机制是适应自然选择的特化产物，旨在应对群体生活的压力。然而，是否存在专门用于从社会信息和个体经验中学习的神经化学途径仍存在广泛争议。认知神经科学研究为社会特定的学习机制提供了混合证据：一些研究发现社会学习和个体学习有可分离的神经相关性，而另一些研究则发现相同的大脑区域和涉及两者的多巴胺介导的计算。在这里，我们证明，就像个体学习一样，当社会信息是主要学习来源时，社会学习会受到多巴胺 D2 受体拮抗剂氟哌啶醇的调节，但当它包含次要的额外元素时则不会。两组（总 N = 43）完成了一项决策任务，该任务需要从自身经验进行主要学习，并从其他来源进行次要学习。对于一组，主要来源是社会的，次要来源是个人的；对于另一组则相反。氟哌啶醇无论社会/个人性质如何，都会影响主要学习，但对来自次要来源的学习没有影响。因此，我们表明，支持学习的多巴胺能机制可以沿着主要-次要的维度进行分离，但不能沿着社会-个体的维度进行分离。这些结果解决了文献中的冲突，并支持了一个不断扩大的领域，该领域表明，人类大脑中的神经化学途径不仅可以专门处理特定的输入，还可以处理社会和非社会线索，并根据手头任务中哪个线索是主要相关的来在两者之间进行仲裁。
