Shisler Rebecca J
University of Georgia, Athens, GA, USA.
Aphasiology. 2005 Jul;19(7):633-650. doi: 10.1080/02687030444000930.
Background: McNeil, Odell, and Tseng (1991), and Murray and colleagues (Murray, 2000; Murray, Holland, & Beeson, 1997a, 1997b) have suggested that variability of performance in patients with aphasia may be due to nonlinguistic cognitive variables, such as attention (i.e., resources, capacity, effort), which affect language comprehension and production. Given the research that has supported the relationship between aphasia and attention deficits, it is important to determine what effect this breakdown in attention may have on cognitive processes for individuals with aphasia.Aims: This study aims to determine if auditory extinction is present in individuals with aphasia, and if so, if this is due to a breakdown in binding. If extinction is found for individuals with aphasia, it would further support the notion that auditory attention difficulties are present among individuals with aphasia, since visual and auditory research has attributed extinction to a breakdown in attention (Baylis, Driver, & Rafal, 1993; Deouell, Bentin, & Soroker, 2000; Deouell & Soroker, 2000). If binding is found to be deficient, the fact that individuals with both left and right hemisphere lesions demonstrate this phenomenon would lead to a number of implications regarding the relationship of attention and aphasia.Methods & Procedures: Auditory extinction, in which one stimulus is not perceived during double simultaneous stimulation (DSS) presentation, was examined in six individuals with aphasia (aged 42-74 years) and six age-matched healthy adults. Two different experiments were conducted in which the auditory stimuli, consisting of male and female voices speaking the letters "T" or "O", were systematically varied to investigate whether binding of identification to location contributes to extinction.Outcomes & Results: Participants with aphasia made more omission errors (extinction) than the control group, and extinction was significantly greater for binding versus nonbinding conditions, suggesting that binding may play a role in extinction for individuals with aphasia.Conclusions: These data provide preliminary results that auditory extinction exists in individuals with aphasia and may be due to deficits in binding together identification and localisation information. Research on this phenomenon and how it influences language would be a worthwhile endeavour for future studies. Moreover, little is known about assessment of auditory attention in patients with aphasia. Further research in this area can lead to advancements in theoretical and functional assessment for individuals with aphasia who have auditory attention and/or binding deficits and require speech-language pathology intervention.
麦克尼尔、奥德尔和曾（1991年），以及默里及其同事（默里，2000年；默里、霍兰德和比森，1997年a，1997年b）指出，失语症患者表现的变异性可能归因于非语言认知变量，如注意力（即资源、能力、努力程度），这些变量会影响语言理解和表达。鉴于已有研究支持失语症与注意力缺陷之间的关系，确定这种注意力障碍对失语症患者认知过程可能产生何种影响非常重要。
本研究旨在确定失语症患者是否存在听觉消退现象，若存在，是否由于整合功能障碍所致。如果在失语症患者中发现了消退现象，这将进一步支持失语症患者存在听觉注意力困难的观点，因为视觉和听觉研究已将消退归因于注意力障碍（贝利斯、德赖弗和拉法尔，1993年；德韦尔、本廷和索罗克，2000年；德韦尔和索罗克，2000年）。如果发现整合功能存在缺陷，那么双侧半球病变患者均表现出这种现象这一事实将对注意力与失语症之间的关系产生诸多影响。
对6名失语症患者（年龄42 - 74岁）和6名年龄匹配的健康成年人进行了听觉消退测试，即在同时呈现双重刺激（DSS）时，其中一个刺激未被感知到的情况。进行了两项不同的实验，实验中的听觉刺激由男性和女性说出字母“T”或“O”的声音组成，通过系统改变刺激来研究识别与位置的整合是否导致消退。
失语症患者比对照组出现更多的遗漏错误（消退），并且在整合条件下的消退明显多于非整合条件，这表明整合可能在失语症患者的消退中起作用。
这些数据提供了初步结果，表明失语症患者存在听觉消退现象，可能是由于识别与定位信息整合不足所致。对这一现象及其对语言影响的研究将是未来研究的一项有价值的工作。此外，对于失语症患者听觉注意力评估知之甚少。该领域的进一步研究可以推动对有听觉注意力和/或整合缺陷且需要言语病理学干预的失语症患者进行理论和功能评估的进展。
