Adcock R Alison, Thangavel Arul, Whitfield-Gabrieli Susan, Knutson Brian, Gabrieli John D E
Department of Psychiatry, University of California, San Francisco, San Francisco, California 94143, USA.
Neuron. 2006 May 4;50(3):507-17. doi: 10.1016/j.neuron.2006.03.036.
We examined anticipatory mechanisms of reward-motivated memory formation using event-related FMRI. In a monetary incentive encoding task, cues signaled high- or low-value reward for memorizing an upcoming scene. When tested 24 hr postscan, subjects were significantly more likely to remember scenes that followed cues for high-value rather than low-value reward. A monetary incentive delay task independently localized regions responsive to reward anticipation. In the encoding task, high-reward cues preceding remembered but not forgotten scenes activated the ventral tegmental area, nucleus accumbens, and hippocampus. Across subjects, greater activation in these regions predicted superior memory performance. Within subject, increased correlation between the hippocampus and ventral tegmental area was associated with enhanced long-term memory for the subsequent scene. These findings demonstrate that brain activation preceding stimulus encoding can predict declarative memory formation. The findings are consistent with the hypothesis that reward motivation promotes memory formation via dopamine release in the hippocampus prior to learning.
我们使用事件相关功能磁共振成像（FMRI）研究了奖励动机性记忆形成的预期机制。在一项金钱激励编码任务中，线索表明即将记忆的场景会带来高价值或低价值奖励。在扫描后24小时进行测试时，与低价值奖励线索后的场景相比，受试者显著更有可能记住高价值奖励线索后的场景。一项金钱激励延迟任务独立地定位了对奖励预期有反应的区域。在编码任务中，在被记住而非被遗忘的场景之前出现的高奖励线索激活了腹侧被盖区、伏隔核和海马体。在所有受试者中，这些区域更大的激活预示着更好的记忆表现。在个体内部，海马体与腹侧被盖区之间相关性的增加与对后续场景的长期记忆增强有关。这些发现表明，刺激编码之前的大脑激活可以预测陈述性记忆的形成。这些发现与奖励动机通过学习前海马体中多巴胺释放促进记忆形成的假设一致。
