RESUMO
A resposta acomodativa de 23 indivíduos normais foi medida com o auto-refrator Canon R-1® para longe (4 metros) durante a fixação de optotipos de dois tamanhos diferentes (20/30 e 20/100). Houve uma hiperacomodação média de 0.24 D na fixação dos optotipos de menor valor angular. As diferenças de acomodação para longe não foram correlacionadas à acomodação tônica medida no escuro e foi sugerido que o efeito da percepção de tamanho possa estar relacionado ao esforço mental (atenção).
Palavras-chave:
acomodação; optotipos; esforço mental
SUMMARY
The far focus of 23 normal subjects was measured, at 4 meters, with the Canon R-1®. Optotypes with two different sizes (20/30 and 20/100) were used as fixation stimuli. With the 20/100 optotypes the mean accommodative response was equal to the distance requirement (0.25D) . With the 20/30 optotypes there was an accommodative lead of 0.24D . The differences in far focus were not correlated with the magnitude of darkfocus. The effect of optotype size on accommodation may be similar to the effect of mental activity.
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Trabalho realizado no Department of Brain and Cognitive Sciences, Infant Vision Laboratory, Massachusetts Institute of Technology, Cambridge, USA.
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Datas de Publicação
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Publicação nesta coleção
Apr 1993