Hoyer William J, Semenec Silvie C, Buchler Norbou E G
Department of Psychology and Center for Health and Behavior, 430 Huntington Hall, Syracuse University, Syracuse, New York 13244-2340, USA.
J Stud Alcohol Drugs. 2007 Sep;68(5):748-58. doi: 10.15288/jsad.2007.68.748.
The objective of the two experiments reported was to examine the effects of acute alcohol intoxication and of alcohol expectancies on controlled search across the visual field.
After receiving an oral dose of 0.5 g/kg alcohol (Experiment 1), an oral dose of 0.7 g/kg alcohol (Experiment 2), or a placebo, participants searched for a target in large arrays of homogeneous distractors that were either highly similar or less similar to the target. Targets were systematically placed at fixation and at visual angles of 2.5 degrees , 5.0 degrees , 7.5 degrees , and 10.0 degrees .
Target detection was less accurate in the placebo condition of both experiments than in the no-beverage control group, suggesting that alcohol expectancies had a negative effect on controlled search. The effects of alcohol at the lower dose and of the placebo on visual search were not different (Experiment 1). At the higher dose, the negative effects of target eccentricity on the accuracy of target detection were larger when targets appeared among highly similar distractors, compared with the placebo condition and with a no-beverage control group. Target eccentricity effects on accuracy or speed were not observed at either dose when targets and distractors were dissimilar.
Acute alcohol intoxication at either a low or high dose and placebo-associated intoxication expectancies have a detrimental effect on controlled visual search in large arrays. Acute alcohol intoxication at a high dosage exaggerates the detrimental effects of target eccentricity and of task difficulty on controlled visual search.
所报告的两项实验的目的是检验急性酒精中毒以及酒精预期对整个视野范围的控制性搜索的影响。
在口服0.5克/千克酒精（实验1）、0.7克/千克酒精（实验2）或安慰剂后，参与者在大量由与目标高度相似或不太相似的同类干扰物组成的阵列中搜索目标。目标被系统地放置在注视点以及视角为2.5度、5.0度、7.5度和10.0度的位置。
在两项实验的安慰剂条件下，目标检测的准确性均低于无饮料对照组，这表明酒精预期对控制性搜索有负面影响。较低剂量的酒精和安慰剂对视觉搜索的影响没有差异（实验1）。在较高剂量时，与安慰剂条件和无饮料对照组相比，当目标出现在高度相似的干扰物中时，目标偏心度对目标检测准确性的负面影响更大。当目标与干扰物不相似时，在两种剂量下均未观察到目标偏心度对准确性或速度的影响。
低剂量或高剂量的急性酒精中毒以及与安慰剂相关的中毒预期对大阵列中的控制性视觉搜索有不利影响。高剂量的急性酒精中毒会加剧目标偏心度和任务难度对控制性视觉搜索的不利影响。
