Two Anatomically and Computationally Distinct Learning Signals Predict Changes to Stimulus-Outcome Associations in Hippocampus.
Two Anatomically and Computationally Distinct Learning Signals Predict Changes to Stimulus-Outcome Associations in Hippocampus.
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DOI：
10.1016/j.neuron.2016.02.014
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发表时间：
2016-03-16
期刊：
影响因子：
16.2
通讯作者：
Behrens TE
中科院分区：
文献类型：
--
作者：
Boorman ED;Rajendran VG;O'Reilly JX;Behrens TE
复杂的认知过程需要复杂的局部处理，但也需要远距离大脑区域之间的相互作用。因此，它是至关重要的，能够研究远程本地计算和它们的神经representations.here我们报告两个解剖学和计算不同的学习信号在外侧眶额皮质（IOFC）和多巴胺能腹侧中脑（VM），预测一个基本的内部模型在海马体中的试验的变化。为了测量学习过程中的局部计算及其与神经表征的相互作用，我们将计算fMRI与逐个试验的fMRI抑制相结合。我们发现，抑制在内侧颞叶网络的变化，一次又一次的试验成比例的刺激结果协会。在交错选择试验期间，我们识别与IOFC中的结果类型和VM中的奖励值相关的学习信号。这些干预选择反馈信号预测了随后的海马抑制变化，表明信号的收敛更新了刺激-结果关联的灵活表示。探针和选择试验评估内部模型的编码和更新学习信号在眶额皮质（OFC）和腹侧中脑（VM）中发现探针试验揭示了模型在内侧颞叶中的神经实例化该实例化的动态变化由OFC和VM学习信号预测Boorman等人。揭示了内部模型的神经编码，该内部模型包括内侧颞叶网络中视觉刺激和奖励类型之间的概率转换。其编码的变化由两个遥远的计算和解剖学上不同的学习信号预测。
Complex cognitive processes require sophisticated local processing but also interactions between distant brain regions. It is therefore critical to be able to study distant interactions between local computations and the neural representations they act on. Here we report two anatomically and computationally distinct learning signals in lateral orbitofrontal cortex (lOFC) and the dopaminergic ventral midbrain (VM) that predict trial-by-trial changes to a basic internal model in hippocampus. To measure local computations during learning and their interaction with neural representations, we coupled computational fMRI with trial-by-trial fMRI suppression. We find that suppression in a medial temporal lobe network changes trial-by-trial in proportion to stimulus-outcome associations. During interleaved choice trials, we identify learning signals that relate to outcome type in lOFC and to reward value in VM. These intervening choice feedback signals predicted the subsequent change to hippocampal suppression, suggesting a convergence of signals that update the flexible representation of stimulus-outcome associations. Probe and choice trials assess the encoding and updating of an internal model Learning signals are found in orbitofrontal cortex (OFC) and ventral midbrain (VM) Probe trials reveal the model’s neural instantiation in the medial temporal lobe Dynamic changes to this instantiation are predicted by OFC and VM learning signals Boorman et al. reveal neural encoding of an internal model comprising probabilistic transitions between visual stimuli and reward types in a medial temporal lobe network. Changes to its encoding are predicted by two distant computationally and anatomically distinct learning signals.