Effect of literacy and education on the visuoconstructional ability of non-demented elderly individuals

Learning to read and to write influences not only verbal skills but also global cognitive performance. Our study aimed to compare the visuoconstructional abilities of elderly illiterates with those of elderly literates. A total of 125 healthy subjects over 65 years old were recruited. Korean version of Mini-Mental State Examination (K-MMSE) and the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) constructional praxis examination were used. We divided subjects into three groups (educated literate n = 53, uneducated literate n = 36 and uneducated illiterate n = 36). Interlocking pentagons drawing, a part of the K-MMSE, was scored using the 6-point hierarchical scale. The uneducated-illiterate group obtained significantly lower scores than did the other two groups. Scores on the ADAS-cog constructional praxis test were highest in the educated-literate group and those in the uneducated-illiterate group obtained the lowest scores. We demonstrated that illiteracy influences not only language performance but also visuoconstructional functioning.