Brion Mélanie, Dormal Valérie, Lannoy Séverine, Mertens Serge, de Timary Philippe, Maurage Pierre
a Laboratory for Experimental Psychopathology, Psychological Sciences Research Institute , Université catholique de Louvain , Louvain-la-Neuve , Belgium.
b Department of Neuropsychiatry , Saint-Martin Hospital , Dave , Belgium.
J Clin Exp Neuropsychol. 2018 Oct;40(8):820-831. doi: 10.1080/13803395.2018.1438371. Epub 2018 Mar 6.
Alcohol-dependent individuals (ALC) simultaneously present decreased inhibitory control and increased attention towards alcohol-related cues. The dual-process models have proposed that these symptoms reflect an imbalance between prefrontal/reflective and limbic/automatic systems, respectively leading to cognitive dysfunctions in executive processes and to alcohol-related bias. However, most previous research has focused on a separate exploration of these systems among ALC, and the direct measure of their interactions remains to be conducted. Moreover, no study has explored the evolution of this imbalance across the successive stages of alcohol-related disorders, and particularly in Korsakoff syndrome (KS), the most frequent neurological complication of alcohol-dependence.
Ten KS, 14 ALC, and 14 matched control participants performed a modified Flanker task, the "Alcohol Flanker Task," based on congruent, incongruent, and neutral conditions with alcohol-related stimuli. This task required inhibitory processing on alcohol-related stimuli and evaluated, through a behavioral approach, the interaction between reflective and automatic systems, as well as its evolution between ALC and KS.
ALC and KS both presented high reactivity towards alcohol-related stimuli, confirming the presence of alcohol-related bias. KS showed increased omission rates (related to distractor interference) while ALC showed higher false-alarm rates (related to prepotent response inhibition). These results suggest that different inhibitory subcomponents might be altered at the successive stages of the pathology, and experimentally confirms the crucial role of the interaction between reflective and automatic processes in alcohol-use disorders.
The present results reinforce the proposal that alcohol-related cues significantly impact inhibitory control in alcohol-related disorders. However, ALC and KS present different patterns of deficits depending on task complexity (i.e., executive load), thus suggesting a dissociation in inhibitory functions when processing alcohol-related cues.
酒精依赖个体同时存在抑制控制能力下降以及对与酒精相关线索的注意力增加的情况。双过程模型提出，这些症状分别反映了前额叶/反思系统和边缘系统/自动系统之间的失衡，进而导致执行过程中的认知功能障碍以及与酒精相关的偏差。然而，此前大多数研究都集中在对酒精依赖个体中这些系统的单独探究上，而它们之间相互作用的直接测量仍有待进行。此外，尚无研究探讨这种失衡在酒精相关障碍的连续阶段中的演变情况，尤其是在酒精依赖最常见的神经并发症科尔萨科夫综合征（KS）中。
10名KS患者、14名酒精依赖个体以及14名匹配的对照参与者进行了一项经过改良的侧抑制任务，即“酒精侧抑制任务”，该任务基于与酒精相关刺激的一致、不一致和中性条件。这项任务要求对与酒精相关的刺激进行抑制处理，并通过行为学方法评估反思系统和自动系统之间的相互作用，以及其在酒精依赖个体和KS患者之间的演变情况。
酒精依赖个体和KS患者对与酒精相关的刺激均表现出高反应性，证实了与酒精相关偏差的存在。KS患者的漏报率增加（与干扰项干扰有关），而酒精依赖个体的误报率更高（与优势反应抑制有关）。这些结果表明，在疾病的连续阶段，不同的抑制子成分可能会发生改变，并通过实验证实了反思过程和自动过程之间的相互作用在酒精使用障碍中的关键作用。
目前的结果强化了这样一种观点，即与酒精相关的线索在酒精相关障碍中对抑制控制有显著影响。然而，酒精依赖个体和KS患者根据任务复杂性（即执行负荷）呈现出不同的缺陷模式，这表明在处理与酒精相关的线索时抑制功能存在分离。
