The influence of schooling on working memory performance in elderly individuals without cognitive decline

Souza-Talarico, Juliana Nery de; Caramelli, Paulo; Nitrini, Ricardo; Chaves, Eliane Corrêa

doi:10.1590/S1980-57642008DN10300009

Abstract

Over recent decades, research on cognition has been developed rapidly toward better understanding the cognitive changes that usually occur during normal aging. There is evidence that elderly individuals have worse working memory performance than young adults. However, the effect of education on this cognitive function remains unclear. Objectives: To analyze the performance of healthy elderly subjects on working memory tasks and to verify the influence of educational level on this performance. Methods: Forty elderly individuals without cognitive impairment and fully independent, were randomly chosen from a group of subjects participating in cultural activities at the university campus. The Digit Span Forward (DSF) test was used to evaluate attention performance. The working memory performance was assessed by the Digit Span Backward (DSB) and the difference between DSF and DSB. The data were statistically analyzed using the Spearman's correlation coefficient to verify the correlation between the Digit Span (DS) scores and the variables age and schooling, while the Multiple Linear Regression Model was used to verify the effect of these variables on the DS scores. Results: A significant positive correlation (r=0.41, p<0.01) as well as a significant association (b=0.506; p=0.001; CI 95%= 0.064/0.237) were found between years of schooling and DSB scores. It was not observed statistical correlation (r= -0.08, p=0.64) or association (b=0.41; p=0.775; CI 95%= -0.049/0.065) between age and DSB scores. Conclusion: In this study, higher levels of schooling were associated with better working memory performance in cognitively healthy elders.

Key words:
aging; education; working memory.

Resumo

Ao longo das últimas décadas pesquisas em cognição têm sido desenvolvidas rapidamente na tentativa de compreender as mudanças cognitivas que acontecem durante o processo de envelhecimento. Existem evidências de que indivíduos idosos têm pior desempenho de memória operacional do que adultos jovens. No entanto, o efeito da escolaridade sobre desempenho ainda não foi totalmente esclarecido. Objetivos: Analisar o desempenho da memória operacional de idosos sem comprometimento cognitivo e verificar a influência da escolaridade neste desempenho. Métodos: Foram avaliados 40 idosos sem comprometimento cognitivo, independentes, escolhidos aleatoriamente em um grupo de idosos que participaram de uma atividade cultural no campus universitário. Foi utilizado o teste de extensão de dígitos na ordem direta (EDOD) para avaliar a atenção. A memória operacional foi examinada a partir do teste de extensão de dígitos na ordem inversa (EDOI) e a partir da diferença entre EDOD e EDOI. Os dados foram estatisticamente analisados, sendo o Coeficiente de Correlação de Spearman utilizado para verificar correlação entre os escores dos testes de extensão de dígitos (ED) e as variáveis idade e escolaridade e o Modelo de Regressão Linear Múltipla para verificar o efeito destas variáveis nos escores do teste ED. Resultados: Foi observada correlação positiva significativa (r=0,41, p<0,01) e associação significativa (b=0,506; p=0,001; CI 95%=0,064/0,237) entre escolaridade e o escore do EDOI. Não foi observada correlação (r= -0,08, p=0,64) ou associação ((b=0,041; p=0,775; CI 95%= -0,049/0,065) entre idade e os escores do EDOI. Conclusão: Neste estudo, maiores níveis de escolaridade associaram-se com melhor desempenho de memória operacional.

Palavras-chave:
envelhecimento; escolaridade; memória operacional.

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

References

¹
Kausler, DM. Learning and memory in normal aging. San Diego: Academic Press; 1994.
²
Burke DM, Mackay DG. Memory, language, and ageing. Philos Trans R Soc Lond B Biol Sci 1997;352:1845-1856.
³
Wingfield A, Kahana MJ. The dynamics of memory retrieval in older adulthood. Can J Psychol 2002; 56:187-199.
⁴
Burke DM, Light LL. Memory and aging: the role of retrieval processes. Psychol Bull 1981;90:513-554.
⁵
Light LL. Memory and aging: four hypotheses in search of data. Am Rev Psychol 1991;42:333-376.
⁶
Light LL, Singh A. Implicit and explicit memory in young and older adults. J Exp Psychol Learn Mem Cogn 1987;13:531-541.
⁷
Light LL, Albertson SA. Direct and indirect tests of memory for category exemplars in young and older adults. Psychol Aging 1989;4:487-492.
⁸
Nyberg L, Backman L, Erngrund K, Olofsson U, Nilsson L. Age differences in episodic memory, semantic memory, and priming: relationships to demographic, intellectual, and biological factors. J Gerontol 1996;51B:234-240.
⁹
Salthouse T A. The processing-speed theory of adult age differences in cognition. Psychol Rev 1996;103:403-428.
¹⁰
Sekuler R, McLaughlin C, Kahana MJ, Wingfield A, Yotsumoto Y . Short-term visual recognition and temporal order memory are both well-preserved in aging. Psychol Aging 2006;21:632-637.
¹¹
Mitchell KJ, Johnson MK, Raye CL, Mather M, D'Esposito M. Aging and reflective processes of working memory: binding and test load deficits. Psychol Aging 2000;15:527-541.
¹²
Mattay VS, Fera F, Tessitore A, et al. Neurophysiological correlates of age-related changes in working memory capacity. Neurosci Letter 2006;392:32-37.
¹³
Economou A, Papageorgiou S, Karageorgiou C. Working-delayed memory difference detects mild cognitive impairment without being affected by age and education. J Clin Exp Neuropsychol 2006;28:528-535.
¹⁴
Nebes RD, Meltzer CC, Whyte EM, et al. The relation of white matter hyperintensities to cognitive performance in the normal old: education matters. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn 2006;13:326-340.
¹⁵
Manly J, Jacobs DM, Sano M, et al. Effect of literacy on neuropsychological test performance in non-demented, education-matched elders. J Int Neuropsychol Soc 1999;5:191-202.
¹⁶
Ostrosky-Solis F, Ardila A, Rosselli M, Lopez-Arango G, Uriel-Mendoza, V. Neuropsychological test performance in illiterate subjects. Arch Clin Neuropsychol 1998;13:645-660.
¹⁷
Nitrini R, Caramelli P, Herrera-Jr E, et al. Performance of illiterate and literate nondemented elderly subjects in two tests of long-term memory. J Int Neuropsychol Soc 2004;10:634-638.
¹⁸
Folstein MF, Folstein SE, Mchugh PR. Minimental state: a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 1975; 12:189-198.
¹⁹
Brucki SMD, Nitrini R, Caramelli P. Suggestions for utilization of the mini-mental state examination in Brazil. Arq Neuropsiquiatr 2003;61:777-781.
²⁰
Jorm AF, Jacomb PA. The informant questionnaire on cognitive decline in the elderly (IQCODE): Socio-demographic correlates, reability, validity and some norms. Psychol Med 1989;19:1015-1022.
²¹
Bustamante SEZ, Bottino CMC, Lopes MA, Azevedo D, Hototian SR, Litvoc J. Combined instruments on the evaluation of dementia in the elderly: preliminary results. Arq Neuropsiquiatr 2003;61:601-606.
²²
Boyd TA, Hooper SR. Psychometric validity of proration and Digit Span substitution for estimating WISC--R verbal and Full Scale IQs. Percept Mot Skills 1987;65:19-25.
²³
Nitrini R, Lefévre BH, Mathias SC, et al. Testes neuropsicológicos de aplicação simples para o diagnóstico de demência. Arq Neuropsiquiatr 1994;52:457-465.
²⁴
Lezak MD, Howieson DB, Loring DW. Neuropsychological assessment. New York: Oxford; 2004.
²⁵
Rosner B. Fundamentals of biostatistics. Boston: PWS publishers; 1986.
²⁶
Ardilla A, Rosselli M. Neuropsychological characteristics of normal aging. Dev Neuropsychol 1989;5:307-320.
²⁷
Kaufman AS, Reynolds CR, McLean JE. Sex, race, residence, region and education differences on the 11WAIS-R subtests. J Clin Psychol 1988;44:231-248.
²⁸
Ostrosky-Solis F, Ardilla A, Rosselli M, Lopez-Arango G, Uriel-Mendoza V. Neuropsychological test performance in illiterate subjects. Arch Clin Neuropsychol 1998;13:645-660.
²⁹
Mortimer JA, Graves A B. Education and other socioeconomic determinants of dementia and Alzheimer's disease. Neurology 1993;43(Suppl 4):39-44.
³⁰
Katzman R. Education and the prevalence of dementia and Alzheimer's disease. Neurology 1993;43:13-20.
³¹
Economou A, Papageorgiou S, Karageorgiou C. Working-delayed memory difference detects mild cognitive impairment without being affected by age and education. J Clin Exp Neuropsychol 2006;28:528-535.
³²
Reis A, Guerreiro M, Petersson KM. A sociodemographic and neuropsychological characterization of an illiterate population. Appl Neuropsychol 2003;10:191-204.
³³
García-Morales P, Gich-Fullà J, Guardia-Olmos J, Peña-Casanova J. Digit span, automatic speech and orientation: amplified norms of the Barcelona Test. Neurologia 1998;13:271-276.
³⁴
Orsini A, Chiacchio L, Cinque M, Cocchiaro C, Schiappa O, Grossi D. Effects of age, education and sex on two tests of immediate memory: a study of normal subjects from 20 to 99 years of age. Percept Mot Skills 1986;63:727-732.
³⁵
Gómez-Pérez E, Ostrosky-Solís F. Attention and memory evaluation across the life span: heterogeneous effects of age and education. J Clin Exp Neuropsychol 2006;28:477-494.
³⁶
Stratta P, Prosperini P, Daneluzzo E, Bustini M, Rossi A. Educational level and age influence spatial working memory and Wisconsin Card Sorting Test performance differently: a controlled study in schizophrenic patients. Psychiatry Res 2001;102:39-48.
³⁷
Baddeley A. The episodic buffer: a new component of working memory? Trends Cogn Sci 2000;4:417-423.
³⁸
Baddeley A. Working memory and language: an overview. J Commun Disord 2003;36:189-208.
³⁹
Mattay VS, Fera F, Tessitore A, et al. Neurophysiological correlates of age-related changes in working memory capacity. Neurosci Lett 2006; 392:32-37.
⁴⁰
Nebes RD, Meltzer CC, Whyte EM, et al. The relation of white matter hyperintensities to cognitive performance in the normal old: education matters. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn 2006;13:326-340.

Publication Dates

Publication in this collection
Jul-Sep 2007

This is an open-access article distributed under the terms of the Creative Commons Attribution License

[1] ¹
Kausler, DM. Learning and memory in normal aging. San Diego: Academic Press; 1994.

[2] ²
Burke DM, Mackay DG. Memory, language, and ageing. Philos Trans R Soc Lond B Biol Sci 1997;352:1845-1856.

[3] ³
Wingfield A, Kahana MJ. The dynamics of memory retrieval in older adulthood. Can J Psychol 2002; 56:187-199.

[4] ⁴
Burke DM, Light LL. Memory and aging: the role of retrieval processes. Psychol Bull 1981;90:513-554.

[5] ⁵
Light LL. Memory and aging: four hypotheses in search of data. Am Rev Psychol 1991;42:333-376.

[6] ⁶
Light LL, Singh A. Implicit and explicit memory in young and older adults. J Exp Psychol Learn Mem Cogn 1987;13:531-541.

[7] ⁷
Light LL, Albertson SA. Direct and indirect tests of memory for category exemplars in young and older adults. Psychol Aging 1989;4:487-492.

[8] ⁸
Nyberg L, Backman L, Erngrund K, Olofsson U, Nilsson L. Age differences in episodic memory, semantic memory, and priming: relationships to demographic, intellectual, and biological factors. J Gerontol 1996;51B:234-240.

[9] ⁹
Salthouse T A. The processing-speed theory of adult age differences in cognition. Psychol Rev 1996;103:403-428.

[10] ¹⁰
Sekuler R, McLaughlin C, Kahana MJ, Wingfield A, Yotsumoto Y . Short-term visual recognition and temporal order memory are both well-preserved in aging. Psychol Aging 2006;21:632-637.

[11] ¹¹
Mitchell KJ, Johnson MK, Raye CL, Mather M, D'Esposito M. Aging and reflective processes of working memory: binding and test load deficits. Psychol Aging 2000;15:527-541.

[12] ¹²
Mattay VS, Fera F, Tessitore A, et al. Neurophysiological correlates of age-related changes in working memory capacity. Neurosci Letter 2006;392:32-37.

[13] ¹³
Economou A, Papageorgiou S, Karageorgiou C. Working-delayed memory difference detects mild cognitive impairment without being affected by age and education. J Clin Exp Neuropsychol 2006;28:528-535.

[14] ¹⁴
Nebes RD, Meltzer CC, Whyte EM, et al. The relation of white matter hyperintensities to cognitive performance in the normal old: education matters. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn 2006;13:326-340.

[15] ¹⁵
Manly J, Jacobs DM, Sano M, et al. Effect of literacy on neuropsychological test performance in non-demented, education-matched elders. J Int Neuropsychol Soc 1999;5:191-202.

[16] ¹⁶
Ostrosky-Solis F, Ardila A, Rosselli M, Lopez-Arango G, Uriel-Mendoza, V. Neuropsychological test performance in illiterate subjects. Arch Clin Neuropsychol 1998;13:645-660.

[17] ¹⁷
Nitrini R, Caramelli P, Herrera-Jr E, et al. Performance of illiterate and literate nondemented elderly subjects in two tests of long-term memory. J Int Neuropsychol Soc 2004;10:634-638.

[18] ¹⁸
Folstein MF, Folstein SE, Mchugh PR. Minimental state: a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 1975; 12:189-198.

[19] ¹⁹
Brucki SMD, Nitrini R, Caramelli P. Suggestions for utilization of the mini-mental state examination in Brazil. Arq Neuropsiquiatr 2003;61:777-781.

[20] ²⁰
Jorm AF, Jacomb PA. The informant questionnaire on cognitive decline in the elderly (IQCODE): Socio-demographic correlates, reability, validity and some norms. Psychol Med 1989;19:1015-1022.

[21] ²¹
Bustamante SEZ, Bottino CMC, Lopes MA, Azevedo D, Hototian SR, Litvoc J. Combined instruments on the evaluation of dementia in the elderly: preliminary results. Arq Neuropsiquiatr 2003;61:601-606.

[22] ²²
Boyd TA, Hooper SR. Psychometric validity of proration and Digit Span substitution for estimating WISC--R verbal and Full Scale IQs. Percept Mot Skills 1987;65:19-25.

[23] ²³
Nitrini R, Lefévre BH, Mathias SC, et al. Testes neuropsicológicos de aplicação simples para o diagnóstico de demência. Arq Neuropsiquiatr 1994;52:457-465.

[24] ²⁴
Lezak MD, Howieson DB, Loring DW. Neuropsychological assessment. New York: Oxford; 2004.

[25] ²⁵
Rosner B. Fundamentals of biostatistics. Boston: PWS publishers; 1986.

[26] ²⁶
Ardilla A, Rosselli M. Neuropsychological characteristics of normal aging. Dev Neuropsychol 1989;5:307-320.

[27] ²⁷
Kaufman AS, Reynolds CR, McLean JE. Sex, race, residence, region and education differences on the 11WAIS-R subtests. J Clin Psychol 1988;44:231-248.

[28] ²⁸
Ostrosky-Solis F, Ardilla A, Rosselli M, Lopez-Arango G, Uriel-Mendoza V. Neuropsychological test performance in illiterate subjects. Arch Clin Neuropsychol 1998;13:645-660.

[29] ²⁹
Mortimer JA, Graves A B. Education and other socioeconomic determinants of dementia and Alzheimer's disease. Neurology 1993;43(Suppl 4):39-44.

[30] ³⁰
Katzman R. Education and the prevalence of dementia and Alzheimer's disease. Neurology 1993;43:13-20.

[31] ³¹
Economou A, Papageorgiou S, Karageorgiou C. Working-delayed memory difference detects mild cognitive impairment without being affected by age and education. J Clin Exp Neuropsychol 2006;28:528-535.

[32] ³²
Reis A, Guerreiro M, Petersson KM. A sociodemographic and neuropsychological characterization of an illiterate population. Appl Neuropsychol 2003;10:191-204.

[33] ³³
García-Morales P, Gich-Fullà J, Guardia-Olmos J, Peña-Casanova J. Digit span, automatic speech and orientation: amplified norms of the Barcelona Test. Neurologia 1998;13:271-276.

[34] ³⁴
Orsini A, Chiacchio L, Cinque M, Cocchiaro C, Schiappa O, Grossi D. Effects of age, education and sex on two tests of immediate memory: a study of normal subjects from 20 to 99 years of age. Percept Mot Skills 1986;63:727-732.

[35] ³⁵
Gómez-Pérez E, Ostrosky-Solís F. Attention and memory evaluation across the life span: heterogeneous effects of age and education. J Clin Exp Neuropsychol 2006;28:477-494.

[36] ³⁶
Stratta P, Prosperini P, Daneluzzo E, Bustini M, Rossi A. Educational level and age influence spatial working memory and Wisconsin Card Sorting Test performance differently: a controlled study in schizophrenic patients. Psychiatry Res 2001;102:39-48.

[37] ³⁷
Baddeley A. The episodic buffer: a new component of working memory? Trends Cogn Sci 2000;4:417-423.

[38] ³⁸
Baddeley A. Working memory and language: an overview. J Commun Disord 2003;36:189-208.

[39] ³⁹
Mattay VS, Fera F, Tessitore A, et al. Neurophysiological correlates of age-related changes in working memory capacity. Neurosci Lett 2006; 392:32-37.

[40] ⁴⁰
Nebes RD, Meltzer CC, Whyte EM, et al. The relation of white matter hyperintensities to cognitive performance in the normal old: education matters. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn 2006;13:326-340.

Brasil