Human orbitofrontal cortex mediates extinction learning while accessing conditioned representations of value
Human orbitofrontal cortex mediates extinction learning while accessing conditioned representations of value
复制标题
DOI：
10.1038/nn1314
复制
发表时间：
2004-10-01
影响因子：
25
通讯作者：
Dolan, RJ
中科院分区：
文献类型：
--
作者：
Gottfried, JA;Dolan, RJ
在灭绝过程中，动物了解到先前的条件刺激（CS+）不再预测显着强化物（无条件刺激，UCS）的传递。啮齿类动物的研究表明，灭绝依赖于杏仁核与前额叶的相互作用，并涉及抑制原始条件反射痕迹的记忆的形成，但实际上并没有消除。人类的灭绝学习是否遵循类似的神经生物学原理尚不清楚。我们使用功能磁共振成像来测量嗅觉厌恶调节和消退学习过程中诱发的人脑活动。眶额皮层和杏仁核的神经反应在灭绝过程中优先增强，这表明反对条件反射的学习机制可能在跨物种中得到保存。此外，通过强化物膨胀来操纵 UCS 厌恶性，我们发现，即使在灭绝过程中，CS+ 仍能在腹侧前额叶皮层的不同区域中保留对 UCS 值表示的访问权。
In extinction, an animal learns that a previously conditioned stimulus (CS+) no longer predicts delivery of a salient reinforcer (unconditioned stimulus, UCS). Rodent studies indicate that extinction relies on amygdala-prefrontal interactions and involves formation of memories that inhibit, without actually erasing, the original conditioning trace. Whether extinction learning in humans follows similar neurobiological principles is unknown. We used functional magnetic resonance imaging to measure human brain activity evoked during olfactory aversive conditioning and extinction learning. Neural responses in orbitofrontal cortex and amygdala were preferentially enhanced during extinction, suggesting potential cross-species preservation of learning mechanisms that oppose conditioning. Moreover, by manipulating UCS aversiveness via reinforcer inflation, we showed that a CS+ retains access to representations of UCS value in distinct regions of ventral prefrontal cortex, even as extinction proceeds.