Alsop Brent, Furukawa Emi, Sowerby Paula, Jensen Stephanie, Moffat Cara, Tripp Gail
Department of Psychology, University of Otago, Dunedin, New Zealand.
Okinawa Institute of Science and Technology Graduate University, Onna, Japan.
J Child Psychol Psychiatry. 2016 Aug;57(8):947-56. doi: 10.1111/jcpp.12561. Epub 2016 Apr 15.
Altered sensitivity to positive reinforcement has been hypothesized to contribute to the symptoms of attention-deficit hyperactivity disorder (ADHD). In this study, we evaluated the ability of children with and without ADHD to adapt their behavior to changing reinforcer availability.
Of one hundred sixty-seven children, 97 diagnosed with ADHD completed a signal-detection task in which correct discriminations between two stimuli were associated with different frequencies of reinforcement. The response alternative associated with the higher rate of reinforcement switched twice during the task without warning. For a subset of participants, this was followed by trials for which no reinforcement was delivered, irrespective of performance.
Children in both groups developed an initial bias toward the more frequently reinforced response alternative. When the response alternative associated with the higher rate of reinforcement switched, the children's response allocation (bias) followed suit, but this effect was significantly smaller for children with ADHD. When reinforcement was discontinued, only children in the control group modified their response pattern.
Children with ADHD adjust their behavioral responses to changing reinforcer availability less than typically developing children, when reinforcement is intermittent and the association between an action and its consequences is uncertain. This may explain the difficulty children with ADHD have adapting their behavior to new situations, with different reinforcement contingencies, in daily life.
对正性强化的敏感性改变被认为是导致注意力缺陷多动障碍（ADHD）症状的原因之一。在本研究中，我们评估了患有和未患有ADHD的儿童根据强化物可得性变化调整其行为的能力。
在167名儿童中，97名被诊断为ADHD的儿童完成了一项信号检测任务，其中对两种刺激的正确辨别与不同频率的强化相关。与较高强化率相关的反应选项在任务过程中无预警地切换了两次。对于一部分参与者，在此之后进行的试验中，无论表现如何，都不会给予强化。
两组儿童最初都对强化频率更高的反应选项产生了偏向。当与较高强化率相关的反应选项发生切换时，儿童的反应分配（偏向）也随之改变，但ADHD儿童的这种效应明显较小。当强化停止时，只有对照组的儿童改变了他们的反应模式。
当强化是间歇性的且行为与其后果之间关系不确定时，ADHD儿童比正常发育儿童更难根据强化物可得性的变化调整其行为反应。这可能解释了ADHD儿童在日常生活中难以根据不同的强化条件使自己的行为适应新情况的原因。
