Gottfried Jay A, O'Doherty John, Dolan Raymond J
Functional Imaging Laboratory, Wellcome Department of Imaging Neuroscience, 12 Queen Square, London WC1N 3BG, UK.
Science. 2003 Aug 22;301(5636):1104-7. doi: 10.1126/science.1087919.
Adaptive behavior is optimized in organisms that maintain flexible representations of the value of sensory-predictive cues. To identify central representations of predictive reward value in humans, we used reinforcer devaluation while measuring neural activity with functional magnetic resonance imaging. We presented two arbitrary visual stimuli, both before and after olfactory devaluation, in a paradigm of appetitive conditioning. In amygdala and orbitofrontal cortex, responses evoked by a predictive target stimulus were decreased after devaluation, whereas responses to the nondevalued stimulus were maintained. Thus, differential activity in amygdala and orbitofrontal cortex encodes the current value of reward representations accessible to predictive cues.
在维持感觉预测线索价值灵活表征的生物体中，适应性行为得以优化。为了识别人类预测奖励价值的中枢表征，我们在使用功能磁共振成像测量神经活动时采用了强化物贬值方法。在一个食欲性条件反射范式中，我们在嗅觉贬值前后都呈现了两种任意的视觉刺激。在杏仁核和眶额皮质中，预测性目标刺激诱发的反应在贬值后减少，而对未贬值刺激的反应则得以维持。因此，杏仁核和眶额皮质中的差异活动编码了预测线索可及的奖励表征的当前价值。
