Lemmonds C A, Wenger G R
Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock 72205, USA.
Behav Pharmacol. 2003 Jul;14(4):279-94. doi: 10.1097/01.fbp.0000080418.18561.93.
The acute effects of ethanol, pentobarbital, D-amphetamine and nicotine were determined in two animal models of attention. This study examined if changing the predictability of the stimulus presentation modifies drug effects under two attention tasks, in male White Carneau pigeons. The first task was a continuous-trial sustained attention task. For seven pigeons, the frequency of signal presentation was constant and predictable, once every 60 s [a fixed-interval 60 s (FI-60) signal presentation]. For seven additional pigeons, the frequency of signal presentation averaged once every 60 s, but the interval between presentations was random and variable [a variable-interval 60 s (VI-60) signal presentation]. Following ethanol (0.3-3 g/kg) and pentobarbital (0.3-13 mg/kg), decreases in p(hit) and large increases in p(false alarm) occurred at doses that did not impair response rates. Following D-amphetamine (0.03-5.6 mg/kg) and nicotine (0.03-3 mg/kg), a significant decrease in p(hit) and increase in p(miss) occurred at doses that did not impair response rates. The second task was a discrete-trial attention task, under which eight pigeons were presented a constant and predictable signal and eight were presented a random and unpredictable signal. Following ethanol (0.3-3 g/kg) and pentobarbital (0.3-13 mg/kg), drug effects on accuracy occurred at doses that suppressed responding. The schedule of signal presentation did not alter the effects of ethanol or pentobarbital. Following D-amphetamine (0.03-5.6 mg/kg) and nicotine (0.03-3 mg/kg), a significant decrease in p(hit) and increase in p(error of omission) occurred at doses that did not impair response latencies, but there were no differences between pigeons responding under the predictable (FI-60) or variable (VI-60) signal presentations. The observation of differential drug effects [e.g. p(false alarms)] on performance under the continuous-trial procedure supports the validity of the procedure for measuring drug effects on attention. However, changes in signal predictability had little effect on control or drug conditions under this continuous-trial sustained attention procedure.
在两种动物注意力模型中测定了乙醇、戊巴比妥、D-苯丙胺和尼古丁的急性效应。本研究在雄性白卡诺鸽中检验了改变刺激呈现的可预测性是否会在两种注意力任务下改变药物效应。第一个任务是连续试验持续注意力任务。对于7只鸽子，信号呈现频率恒定且可预测，每60秒一次[固定间隔60秒（FI-60）信号呈现]。另外7只鸽子，信号呈现频率平均每60秒一次，但呈现间隔是随机且可变的[可变间隔60秒（VI-60）信号呈现]。给予乙醇（0.3 - 3 g/kg）和戊巴比妥（0.3 - 13 mg/kg）后，在不损害反应率的剂量下，击中概率（p(hit)）降低，误报概率（p(false alarm)）大幅增加。给予D-苯丙胺（0.03 - 5.6 mg/kg）和尼古丁（0.03 - 3 mg/kg）后，在不损害反应率的剂量下，击中概率显著降低，漏报概率（p(miss)）增加。第二个任务是离散试验注意力任务，在此任务下，8只鸽子接受恒定且可预测的信号，8只鸽子接受随机且不可预测的信号。给予乙醇（0.3 - 3 g/kg）和戊巴比妥（0.3 - 13 mg/kg）后，在抑制反应的剂量下出现了对准确性的药物效应。信号呈现时间表并未改变乙醇或戊巴比妥的效应。给予D-苯丙胺（0.03 - 5.6 mg/kg）和尼古丁（0.03 - 3 mg/kg）后，在不损害反应潜伏期的剂量下，击中概率显著降低，漏报错误概率（p(error of omission)）增加，但在接受可预测（FI-60）或可变（VI-60）信号呈现的鸽子之间没有差异。在连续试验程序下观察到的药物对表现的不同效应[如误报概率（p(false alarms)）]支持了该程序用于测量药物对注意力影响的有效性。然而，在这种连续试验持续注意力程序下，信号可预测性的变化对对照或药物条件影响很小。
