Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, United States of America.
Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, United States of America.
Pharmacol Biochem Behav. 2020 Dec;199:173069. doi: 10.1016/j.pbb.2020.173069. Epub 2020 Nov 2.
Measurement of attentional performance in animal behavioral research allows us to investigate neural mechanisms underlying attentional processes and translate results to better understand human attentional function, dysfunction and drug treatments to reverse dysfunction. One useful method to measure attention in experimental animal studies is to use an operant visual signal detection paradigm, consisting of two levers and the rapid flashing of a cue lamp to signal a reward. In this study, we tested the relative sensitivity of this task when using different variants of the stimulus signal, varying brightness or duration of the light cue. To investigate roles of different neural systems underlying attentional processes, we assessed the sensitivity of attentional performance with these two different cue variations with blockade of muscarinic acetylcholine and NMDA glutamate receptors with scopolamine and MK-801 (dizocilpine). Operant signal detection was tested using a signal light that varied in intensity (0.027, 0.269, 1.22 lx) of the signal light or in a paradigm which varied the duration (0.5 s, 1 s, 2 s) of the signal light. Both methods of assessing attention showed construct validity for producing gradients of accuracy for signal detection; the dimmest cue led to less accurate responding compared to the brighter cues, and the shortest duration led to less accuracy compared to the longer durations. However, the tests differed in their sensitivity to pharmacological disruption. With the duration test, the high dose of MK-801 along with co-exposure of scopolamine and MK-801 caused a significant reduction of hit and rejection accuracy. Conversely, the intensity variation test did not show significant differences as a function of drug exposures. These data suggest that changes in signal duration, rather than signal intensity, during operant signal detection may have higher sensitivity to detecting drug effects and be a more useful technique for examining pharmacological interventions on attentional behavior and performance.
在动物行为研究中测量注意力表现，使我们能够研究注意力过程背后的神经机制，并将研究结果转化为更好地理解人类注意力功能、功能障碍和药物治疗以逆转功能障碍。在实验动物研究中测量注意力的一种有用方法是使用操作性视觉信号检测范式，该范式由两个杠杆和快速闪烁的信号灯组成，以信号奖励。在这项研究中，我们测试了使用不同刺激信号变体时该任务的相对敏感性，这些变体改变了光信号的亮度或持续时间。为了研究注意力过程背后不同神经系统的作用，我们使用这两种不同的线索变化评估了注意力表现的敏感性，使用阿托品和 MK-801（地卓西平）阻断毒蕈碱乙酰胆碱和 NMDA 谷氨酸受体。使用信号光的操作性信号检测，信号光的强度（0.027、0.269、1.22 lx）或信号光的持续时间（0.5 s、1 s、2 s）发生变化。评估注意力的这两种方法都显示出产生信号检测准确性梯度的结构有效性；与较亮的提示相比，最暗的提示导致响应准确性降低，与较长的持续时间相比，较短的持续时间导致准确性降低。然而，这些测试在其对药理学破坏的敏感性方面有所不同。在持续时间测试中，MK-801 的高剂量以及阿托品和 MK-801 的共同暴露导致击中率和拒绝率准确性显著降低。相反，强度变化测试并未显示出作为药物暴露函数的显著差异。这些数据表明，在操作性信号检测过程中信号持续时间而不是信号强度的变化可能对检测药物效应具有更高的敏感性，并且是一种更有用的技术，用于研究注意力行为和表现的药物干预。
