실어증 환자의 단기기억 및 작업기억용량과 실어증 중증도 및 문장처리와의 상관 = Performances on Short-Term and Working Memory Tasks and Their Relationships to Aphasia Severity and Auditory Comprehension in Normal Elderly Adults and People with Aphasia

국문 초록 (Abstract)

배경 및 목적: 실어증 환자들의 단기기억(short-term memory) 및 작업기억용량(working memory capacity)의 개인차에 따른 실어증 중증도 및 문장처리능력 차이에 관한 연구가 주목을 받고 있다. 하지만, 정상인을 대상으로 개발된 산출을 기반으로 하는 기억기제 평가방법을 실어증 환자들에게 직접적으로 적용하는 데는 다양한 문제가 제기될 수 있다. 따라서 본 연구에서는 기존에 사용되던 단기 및 작업기억과제(Martin, Kohen & Kalinyak-Fliszar, 2008)를 지시하기폭과제(pointing span task)로 변형한 후, 숫자 및 단어로 자극 양상을 조절하여 과제별 수행력 차이를 살펴보았으며, 기억과제들과 실어증 중증도 및 문장처리 능력에 관한 상관관계를 분석하였다. 방법: 대상자는 영어를 모국어로 사용하는 실어증 환자 20명과 정상 노인 30명이다. 단기기억과제로는 숫자 및 단어 바로 따라지시하기 과제가 사용되었으며, 작업기억과제로는 숫자 및 단어 거꾸로 따라지시하기 과제를 사용하였다. 실어증 중증도는 Porch Index of Communicative Ability(PICA)를 통해 평가되었으며, 문장처리능력은 Computerized Revised Token Test(CRTT)를 사용하여 살펴보았다. 결과: 두 집단 모두 단기기억과제에 비해 작업기억과제에서 더 낮은 수행력을 보였으며, 숫자에 비해 단어에서 더 어려움을 보였다. 두 집단 간의 차이가 가장 크게 나타나는 과제는 숫자 거꾸로 따라지시하기 과제였다. 주성분 분석 결과에 따르면, 네 가지 기억과제는 하나의 공통적인 성분으로 추출될 수 있으며, 총분산의 80% 가량을 설명하는 것으로 나타났다. 논의 및 결론: 네 가지 기억과제의 공통적인 기제를 개념화하자면, 짧은 시간동안 정보를 저장하거나 조작하는 데 기여하는 인지적 기제라고 할 수 있다. 네 가지 기억과제 중, 실어증 중증도와 실어증 환자의 문장처리 수행력을 유의하게 예측한 변수는 숫자 바로 따라지시하기 과제였다. 작업기억용량이론에 바탕을 둔 결과 해석이 논의되었으며 한국어를 사용하는 실어증 환자를 위한 작업기억과제 개발에 대한 필요성도 제기되었다.

다국어 초록 (Multilingual Abstract)

Background & Objectives: Short-term memory and working memory capacities have gained considerable attention as underlying cognitive mechanisms, which may account for language processing difficulties in people with aphasia. However, there are limitations to the employment of short-term and working memory tasks for assessing normal cognitive processing in order to evaluate language-impaired clinical populations. The current study investigated 1) the performance differences between people with aphasia and normal elderly adults in short-term memory and working memory tasks when the stimuli modality was manipulated using digits and words and 2) how their performances on the memory tasks were related to aphasia severity and sentence processing. Methods: Twenty people with aphasia and 30 normal elderly adults participated in the present study. Digit forward and word forward span tasks served as short-term memory tasks, and digit backward and word backward span tasks served as working memory tasks. Porch Index of Communicative Ability (PICA) was used as a measure of language impairment severity, and the Computerized Revised Token Test (CRTT) was a measure of sentence processing. Results: Both groups showed greater difficulties in working memory tasks than short-term memory tasks and those involving words compared to those involving digits. The greatest group differences were found in the digit backward span task. Principal component analysis of four span tasks revealed that a one-factor solution accounted for approximately 80% of the total variance in both groups, indicating that the four span measures served as a unified index of the underlying memory-related cognitive mechanism that is responsible for maintaining and manipulating information. Among the four span measures, the digit forward task significantly predicted aphasia severity and sentence-processing abilities in people with aphasia. Discussion & Conclusion: Results were partially consistent with the working memory capacity theory. Korean versions of short-term and/or working memory span tasks need to be developed in order to investigate the underlying cognitive mechanisms responsible for language impairments in aphasia. (Korean Journal of Communication Disorders 2010;15;285-297)

목차 (Table of Contents)

• Ⅰ. 서 론
• Ⅱ. 연구 방법
• Ⅲ. 연구 결과
• Ⅳ. 논의 및 결론

참고문헌 (Reference)

• 1 Kane, M. J., "Working-memory capacity, proactive interference, and divided attention: Limits on long-term memory retrieval" 26 : 336-358, 2000
• 2 Kane, M. J., "Working-memory capacity and the control of attention: The contributions of goal neglect, response competition, and task set to stroop interference" 132 : 47-70, 2003
• 3 Engle, R. W., "Working memory, short-term memory, and general fluid intelligence: A latentvariable approach" 128 : 309-331, 1999
• 4 Baddeley, A. D., "Working memory, Recent advances in learning and motivation, Vol. 8" Academic Press 47-90, 1974
• 5 Engle, R. W., "Working memory capacity as executive attention" 19-23, 2002
• 6 Kane, M. J., "Working memory capacity and the top-down control of visual search: Exploring the boundaries of executive attention" 32 : 749-777, 2006
• 7 Tompkins, C. A., "Working memory and inference revision in brain-damaged and normally aging adults" 37 : 896-912, 1994
• 8 Baddeley, A. D., "Working memory" Oxford University Press 1986
• 9 Caspari, I., "Working Memory and Aphasia" 37 : 205-223, 1998
• 10 Engle, R. W., "What is working memory capacity?, The nature of remembering: Essays in honor of Robert G. Crowder" American Psychological Association 297-314, 2001
• 11 Sung, J. E., "Verbal working memory and its relationship to sentence-level reading and listening comprehension in persons with aphasia" 23 : 1040-1052, 2009
• 12 Waters, G. S., "The reliability and stability of verbal working memory measures" 35 : 550-564, 2003
• 13 Waters, G. S., "The relationship between age, processing speed, working memory capacity, and language comprehension" 13 : 403-413, 2005
• 14 McNeil, M. R., "The nature of aphasia in adults, Speech, language, and hearing, Vol. II" Saunders 1982
• 15 Goodglass, H., "The assessment of aphasia and related disorders (2nd ed.)" Lea & Febiger 1983
• 16 Porch, B. E., "The Porch Index of Communicative Ability (3rd ed.)" Consulting Psychologists Press 2001
• 17 Raven, J. C., "The Coloured Progressive Matrices" The Psychological Corporation 1965
• 18 Baddeley, A. D., "Short-term and working memory, The Oxford handbook of memory" Oxford University Press 77-92, 2000
• 19 Friedmann, N., "Sentence comprehension and working memory limitation in aphasia: A dissociation between semantic-syntactic and phonological reactivation" 86 : 23-39, 2003
• 20 Salthouse, T. A., "Resource-reduction interpretations of cognitive aging" 8 : 238-272, 1988
• 21 Raven, J. C., "Raven’s Progressive Matrices and Vocabulary Scales" Psychological Corporation 1977
• 22 Morris, R. G., "Processing resources and age differences in working memory" 16 : 362-366, 1988
• 23 Kay, J., "PALPA: Psycholinguistic Assessments of Language Processing in Aphasia" Lawrence Erlbaum Associates 1992
• 24 Thompson, C. K., "Northwestern Assessment of Verbs and Sentences-Revised (NAVS-R)" Northwestern University 2008
• 25 Botwinick, J., "Memory, related functions and age" 1974
• 26 Cattell, R. N., "Measuring intelligence with the Culture Fair tests" Institute for Personality and Ability Testing 1973
• 27 Turner, M. L., "Is working memory capacity task dependent?" 28 : 127-154, 1989
• 28 Daneman, M., "Individual differences in working memory and reading" 19 : 450-466, 1980
• 29 Engle, R. W., "Executive attention, working memory capacity, and a two-factor theory of cognitive control, The psychology of learning and motivation" Academic Press 145-199, 2004
• 30 Cowan, N., "Evolving conceptions of memory storage, selective attention, and their mutual constraints within the human information processing system" 104 : 163-191, 1988
• 31 McNeil, M. R., "Defining aphasia: Some theoretical and clinical implications of operating from a formal definition" 15 : 901-911, 2001
• 32 McNeil, M. R., "Concurrent validation of the Computerized Revised Token Test (CRTT) and three experimental reading CRTTR versions in normal elderly individuals and persons with aphasia" Teton Village 2008
• 33 Cowan, N., "Attention and memory: An integrated framework" Oxford University Press 1995
• 34 Bayles, K., "Arizona Battery for Communication Disorders of Dementia" 1993
• 35 Caplan, D., "Aphasic disturbances of syntactic comprehension and working memory capacity" 12 : 637-649, 1995
• 36 Schuell, H., "Aphasia in adults: Diagnosis, prognosis and treatment" Hoeber Meducal Division, Harper & Row Publishers 1964
• 37 Kertesz, A., "Aphasia and associated disorders: Taxonomy, localization and recovery" Grune & Stratton 1979
• 38 Darley, F. L., "Aphasia" W. B. Saunders 1982
• 39 Ivanova, M., "An eye-tracking method to investigate working memory in individuals with and without aphasia" Isle of Palms 2010
• 40 Waters, G. S., "Age, working memory, and on-line syntactic processing in sentence comprehension" 16 : 128-144, 2001
• 41 Miyake, A., "Acapacity approach to syntactic comprehension disorders: Making normal adults perform like aphasic patients" 11 : 671-717, 1994
• 42 Craik, F. I. M., "A functional account of age differences in memory, Human memory and cognitive capabilities" North-Holland 409-422, 1986
• 43 Martin, N., "A diagnostic battery to assess language and short-term memory deficits in aphasia" Teton Village 2008
• 44 Just, M. A., "A capacity theory of comprehension: Individual differences in working memory" 99 : 122-149, 1992