Ray Madelyn H, Hite Tyler, Gallo Mark, Pickens Charles L
Department of Psychological Sciences, Kansas State University, 492 Bluemont Hall, 1114 Mid-Campus Dr. North, Manhattan, KS, United States, 66506..
Physiol Behav. 2018 Nov 1;196:176-184. doi: 10.1016/j.physbeh.2018.08.021. Epub 2018 Sep 4.
In humans, prior alcohol use is linked with impulsivity and impaired decision-making, but the nature of this relationship is unclear. In a previous study in rats, we found that prior alcohol access led to over-responding in go/no-go discrimination training, but had no effect on discrimination learning. It was unclear whether this over-responding effect would occur in a reversal learning task, or whether prior alcohol would impair reversal learning in our task. In the present experiments, we determined whether six weeks of chronic intermittent alcohol access would induce over-responding or impair reversal learning in our task. Our task allowed for multiple responses/trial with limited reinforcement, so over-responding could be assessed. In Exp. 1, we gave three days of discrimination training prior to access to 20% alcohol or water, then reversed task contingencies starting 4 days after the end of alcohol access. In Exp. 2, we gave either three or six days of discrimination training prior to the same alcohol access and reversal learning procedures to determine if the original training length would affect alcohol's behavioral effects. We found no reversal learning deficits in either experiment. Across both experiments, we found that the Alcohol group exhibited over-responding to the active lever, but this effect was smaller than in our previous discrimination experiments. Our data suggest that there are behavioral changes after voluntary alcohol access that can be missed by some discrimination/reversal learning assessments, and our over-responding task can detect these transient changes. However, over-responding is more pronounced in discrimination than reversal learning.
在人类中，既往饮酒与冲动性和决策能力受损有关，但这种关系的本质尚不清楚。在之前一项针对大鼠的研究中，我们发现既往接触酒精会导致在“去/不去”辨别训练中反应过度，但对辨别学习没有影响。尚不清楚这种反应过度效应是否会在逆向学习任务中出现，或者既往饮酒是否会损害我们任务中的逆向学习。在本实验中，我们确定六周的慢性间歇性酒精接触是否会在我们的任务中诱发反应过度或损害逆向学习。我们的任务允许在有限强化的情况下进行多次反应/试验，因此可以评估反应过度情况。在实验1中，在给予20%酒精或水之前，我们进行了三天的辨别训练，然后在酒精接触结束后4天开始改变任务条件。在实验2中，在相同的酒精接触和逆向学习程序之前，我们分别进行了三天或六天的辨别训练，以确定最初的训练时长是否会影响酒精的行为效应。我们在两个实验中均未发现逆向学习缺陷。在两个实验中，我们发现酒精组对活动杠杆表现出反应过度，但这种效应比我们之前的辨别实验中要小。我们的数据表明，自愿接触酒精后会出现行为变化，而一些辨别/逆向学习评估可能会忽略这些变化，并且我们的反应过度任务能够检测到这些短暂变化。然而，反应过度在辨别学习中比在逆向学习中更为明显。
