ATTENTION AND DUAL-TASK INTERFERENCE

我们建议使用翻译行为科学的策略，使范式具有更大的分析能力，在精神分裂症的注意力的研究，并进一步发展相关的精神分裂症的基本范式。双任务干扰研究对于阐明精神分裂症患者注意力限制的过程具有特殊的前景。它们允许直接测试两个重叠的任务的性能是否受损是由于特定形式的中央结构瓶颈，而不是分级的能力共享，这将是预测的处理资源限制。使用一种特殊类型的双任务范式，心理不应期范式，也可以确定结构加工瓶颈的位置，即某些认知操作不能同时完成的加工点。加州大学洛杉矶分校的五项研究，96例前驱期，100例首次发作， 和80名慢性患者和相同数量的人口统计学上可比较的正常受试者将使用心理不应期范式，该范式在基础认知研究中具有良好的记录效用，用于检测和定位双任务表现中的处理瓶颈。前四个实验将测试影响双重任务干扰的“认知结构”是否在有前驱症状的人或首次发作或慢性精神分裂症中改变 患者，使得处理瓶颈除了响应选择过程之外还包括感知编码或响应产生。第五项临床研究将检查从长期记忆中提取是否是正常受试者的中央瓶颈的一个组成部分，如果是这样，记忆提取是否会导致患者双重任务表现的异常大的中断（即更长的延迟）。短期纵向研究将确定双任务干扰的某些组成部分是否会随着时间的推移而变得更加严重，预测精神病发作，并且是功能结果的特别强的预测因子。知觉编码，记忆检索，反应选择和反应生产过程的预测贡献将被区分。虽然这些初步的临床研究已经完成，但UCSD的基本认知范式的发展将解决有关双重任务情况下准备过程的关键问题。精神分裂症患者在其他准备过程和工作记忆方面的缺陷表明了开发这些新范式的相关性，这些新范式随后将以改进的形式应用于加州大学洛杉矶分校的临床样本。这项研究将大大增加我们对精神分裂症中注意力障碍、症状发展和功能结果之间联系的理解。

We propose to use a translational behavioral science strategy to bring paradigms with greater analytic power to the study of attention in schizophrenia and also to develop further basic paradigms of relevance to schizophrenia. Dual-task interference studies have particular promise for clarifying the processes involved in attentional limitations in schizophrenia. They allow direct tests of whether impairments during performance of two overlapping tasks are due to specific forms of central structural bottlenecks, as opposed to the graded capacity sharing that would be predicted by processing resource limits. Using a specific type of dual-task paradigm, the Psychological Refractory Period paradigm, it is also possible to identify the locus of structural processing bottlenecks, that is, processing points at which certain cognitive operations cannot be completed simultaneously. Five studies at UCLA with 96 prodromal, 100 first-episode, and 80 chronic patients and equal numbers of demographically comparable normal subjects will use Psychological Refractory Period paradigms that have well-documented utility in basic cognitive research for detecting and locating a processing bottleneck in dual-task performance. The first four will test whether the "cognitive architecture" affecting dual-task interference is altered in persons with prodromal symptoms or in first-episode or chronic schizophrenia patients, such that the processing bottleneck includes perceptual encoding or response production in addition to response selection processes. The fifth clinical study will examine whether retrieval from long-term memory is a component of the central bottleneck as it is in normal subjects and, if so, whether memory retrieval causes an abnormally large disruption (i.e. longer delay) in dual-task performance in the patients. Short-term longitudinal studies will determine whether certain components of dual-task interference become more severe over time, predict psychosis onset, and are particularly strong predictors of functional outcome. Predictive contributions of perceptual encoding, memory retrieval, response selection, and response production processes will be differentiated. While these initial clinical studies are completed, development of basic cognitive paradigms at UCSD will address critical issues concerning preparatory processes in dual-task situations. Deficits in other preparatory processes and in working memory in schizophrenia indicate the relevance of developing these new paradigms, which will later be applied in refined form with clinical samples at UCLA. This research should substantially increase our understanding of the links between specific forms of attentional impairment, symptom development, and functional outcome in schizophrenia.