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. (JINS, 2011, 17, 934–939)

Background: In Asia, where illiteracy rates are high, determining the degree to which neuropsychological measures can be used to identify cognitive impairment in illiterate elders is important. The aim of this study was to evaluate the effectiveness of using formal neuropsychological assessments to distinguish healthy illiterate elders from dementia patients.

Methods: We compared the cognitive performance of healthy elders who were illiterate (illiterate NC, n = 25) with those who were literate (literate NC, n = 25), literate patients with mild Alzheimer's disease (literate AD, n = 25), and illiterate patients with mild AD (illiterate AD, n = 25). Neuropsychological measures included the Mini-Mental State Examination (MMSE), the verbal fluency test, the Boston naming test, the Rosen drawing test, and the verbal learning test.

Results: In the between-group analyses, the scores on all tests, except verbal fluency and recognition memory, were lower for illiterate NC compared to the literate NC. The scores on the MMSE, Boston naming test, Rosen drawing test, and immediate free recall could not distinguish the illiterate NC from literate AD. However, the scores on all tests, except the Rosen drawing test, could distinguish illiterate NC from illiterate AD. ROC analyses showed the same pattern of results. In addition, age-, sex-, and education-matched cut-off scores of all tests, except immediate recall and delayed recall trials of the verbal learning test, showed good specificities in participants who were illiterate compared to those in participants who were literate.

Conclusion: These findings suggest that the impact of literacy on neuropsychological test performance is an important aspect of cognitive evaluations for elders who are illiterate.

Background: Low education and illiteracy are associated with an increased risk of dementia. This study aimed to develop a neuropsychological test battery applicable to both illiterate and literate elderly and to assess its reliability and validity for a diagnosis of dementia.

Methods: We developed the Literacy Independent Cognitive Assessment (LICA), which consists of 13 subtests assessing memory, language, visuoconstruction, executive function, attention and calculation. We investigated its reliability and validity on 152 patients with dementia, 66 with mild cognitive impairment and 639 normal controls.

Results: The subtests were found to be applicable to most of the illiterate normal controls (97.3%) and were found to have high inter-rater reliabilities (r = 0.85–1.00, p < 0.001) and moderate to high test-retest reliabilities (r = 0.50–0.86, p < 0.001). The LICA performed well in discriminating participants across Clinical Dementia Rating stages and showed excellent internal consistency and good concurrent validity with the Korean Mini-mental State Examination in both literate and illiterate participants. The area under the curve of the receiver operating characteristic was 0.985 in each of the two literacy groups. Sensitivity and specificity of the LICA to make a diagnosis of dementia was 91.9% and 91.8% at the cutoff point of 186.0 in the literate subjects and 96.2% and 91.1% at the cutoff point of 154.5 in the illiterate subjects. The battery was factored into two separate factors consisting of verbal memory tests and tests for other cognitive domains.

Conclusion: The LICA is a valid and reliable instrument for a diagnosis of dementia in both illiterate and literate elderly.

Background: Dementia is becoming a major public health problem in Latin America (LA), yet epidemiological information on dementia remains scarce in this region. This study analyzes data from epidemiological studies on the prevalence of dementia in LA and compares the prevalence of dementia and its causes across countries in LA and attempts to clarify differences from those of developed regions of the world.

Methods: A database search for population studies on rates of dementia in LA was performed. Abstracts were also included in the search. Authors of the publications were invited to participate in this collaborative study by sharing missing or more recent data analysis with the group.

Results: Eight studies from six countries were included. The global prevalence of dementia in the elderly (≥65 years) was 7.1% (95% CI: 6.8–7.4), mirroring the rates of developed countries. However, prevalence in relatively young subjects (65–69 years) was higher in LA studies The rate of illiteracy among the elderly was 9.3% and the prevalence of dementia in illiterates was two times higher than in literates. Alzheimer's disease was the most common cause of dementia.

Conclusions: Compared with studies from developed countries, the global prevalence of dementia in LA proved similar, although a higher prevalence of dementia in relatively young subjects was evidenced, which may be related to the association between low educational level and lower cognitive reserve, causing earlier emergence of clinical signs of dementia in the LA elderly population.

Background: This study aims to establish the incidence rates of Alzheimer's disease (AD) and to understand the relations between illiteracy and AD in the Korean Yonchon survey cohort.

Methods: A community-based, dementia-free cohort of 966 people aged 65 years and older was followed up for an average of 5.4 ± 1.60 years to detect incident AD cases using a two-phase procedure. Age-specific incidence rates were calculated using a person-years approach with Poisson distribution confidence intervals. Data were analyzed using the Cox proportional hazards model to find the hazard ratio of illiteracy.

Results: The participating percentage of the survivors was 86.4% and 74 subjects were diagnosed with AD. Incidence rates per 1000 person-years were 20.99 (95% CI 16.48 to 26.35) for AD. The hazard ratio of illiteracy was 1.78 (95% CI 1.08 to 2.93) adjusted for age, sex, educational level. AD developed more rapidly with aging in the illiterate group than in the literate group.

Conclusions: Illiteracy is associated with a higher risk of AD and the risk increases with age.

Previous studies have shown a significant association between reading skills and the performance on visuo-motor tasks. In order to clarify whether reading and writing skills modulate non-linguistic domains, we investigated the performance of two literacy groups on a visuo-motor integration task with non-linguistic stimuli. Twenty-one illiterate participants and twenty matched literate controls were included in the experiment. Subjects were instructed to use the right or the left index finger to point to and touch a randomly presented target on the right or left side of a touch screen. The results showed that the literate subjects were significantly faster in detecting and touching targets on the left compared to the right side of the screen. In contrast, the presentation side did not affect the performance of the illiterate group. These results lend support to the idea that having acquired reading and writing skills, and thus a preferred left-to-right reading direction, influences visual scanning. (JINS, 2007, 13, 359–364.)

Researchers of cognitive processing in illiteracy have proposed that the acquisition of literacy modifies the functional organization of the brain. They have suggested that, while illiterate individuals have access only to innate semantic processing skills, those who have learned the correspondence between graphemes and phonemes have several mechanisms available to them through which to process oral language. We conducted 2 experiments to verify that suggestion with respect to language processing, and to elucidate further the differences between literate and illiterate individuals in the cognitive strategies used to process oral language, as well as hemispheric specialization for these processes. Our findings suggest that semantic processing strategies are qualitatively the same in literates and illiterates, despite the fact that overall performance is augmented by increased education. In contrast, explicit processing of oral information based on phonological characteristics appears to be qualitatively different between literates and illiterates: effective strategies in the processing of phonological information depend upon having had a formal education, regardless of the level of education. We also confirmed the differential abilities needed for the processing of semantic and phonological information and related them to hemisphere-specific processing. (JINS, 2004, 10, 818–827.)

Cognitive evaluation in developing countries is a difficult undertaking due to low levels of schooling and particularly the illiteracy still frequent in the elderly. This study was part of the epidemiologic evaluation of dementia in Catanduva, Brazil, and had the objective of comparing the performance of illiterate and literate nondemented elderly individuals in 2 tests of long-term memory—the delayed recall of a word list from the CERAD and the delayed recall of common objects presented as simple drawings from the Brief Cognitive Screening Battery (BCSB). Fifty-one elderly subjects (23 illiterates) were evaluated, and the performance of the illiterates and literates differed in the CERAD memory test, but not in the BCSB memory test. This test may be more suitable for the assessment of long-term memory in populations with a high frequency of illiterates, and therefore might prove to be a useful screening tool for the diagnosis of dementia. (JINS, 2004, 10, 634–638.)

A sample of 20 right-handed Aruaco Indians (12 male, 8 female; age 8–30 years) from the Sierra Nevada de Santa Marta (Colombia) participated in this study. A brief neuropsychological test battery (visuoconstructive and visuoperceptual abilities, memory, ideomotor praxis, verbal fluency, spatial abilities, concept formation) was individually administered. In addition, a handedness questionnaire was included. In some neuropsychological tests performance was virtually perfect (Recognition of Overlapped Figures and Ideomotor Praxis Ability test), whereas performance in other tests was impossible (e.g., Block Design using a time limit). It was proposed that two types of variables were significantly affecting performance: (1) educational level; and (2) cultural relevance. Some tests appeared significant and meaningful whereas others were meaningless and even impossible to understand. The appropriateness of current neuropsychological instruments for cross-cultural assessment is discussed. (JINS, 2001, 7, 510–515.)

Departing from the observation that illiterates significantly underscore in some neuropsychological tests, a learning-to-read method named NEUROALFA was developed. NEUROALFA is directed to reinforce these underscored abilities during the learning-to-read process. It was administered to a sample of 21 adult illiterates in Colima (Mexico). Results were compared with 2 control groups using more traditional procedures in learning to read. The NEUROPSI neuropsychological test battery was administered to all the participants before and after completing the learning-to-read training program. All 3 groups presented some improvement in the test scores. Gains, however, were significantly higher in the experimental group in Orientation in Time, Digits Backward, Visual Detection, Verbal Memory, Copy of a Semi-Complex Figure, Language Comprehension, Phonological Verbal Fluency, Similarities, Calculation Abilities, Sequences, and all the recall subtests, excluding Recognition. Performance in standard reading tests was also significantly higher in the experimental group. Correlations between pretest NEUROPSI scores and reading ability were low. However, correlations between posttest NEUROPSI scores and reading scores were higher and significant for several subtests. Results are interpreting as supporting the assumption that reinforcement of those abilities in which illiterates significantly underscore results in a significant improvement in neuropsychological test scores and strongly facilitates the learning-to-read process. The NEUROALFA method of teaching reading to adult illiterates is beginning to be used extensively in Mexico. To our knowledge, this is the first attempt to apply neuropsychological principles to social problems. (JINS, 2000, 6, 789–801.)

Since constructional apraxia is often concomitant with brain lesions, the study of constructional tasks in the non-brain-damaged population might be useful in helping to disentangle other causal factors. This paper explores the performance of illiterate individuals (N = 29) as compared to that of semiliterates (N = 21) and literates (N = 23) in order to see the effect of reading and writing abilities on constructional tasks. Each participant was asked to construct 4 figures based upon models having varying degrees of complexity. A global criterion of lack of fidelity and several analytic criteria (related to distortion, rotation, and disarticulation errors) were used to evaluate performance. Although illiterates generally made more errors than semiliterates and semiliterates more than literates, only some of these differences were statistically significant. Significant differences were found for lack of global fidelity and disarticulation errors when all 4 figures were considered together. Subtler data emerged with respect to single figures. (JINS, 2000, 6, 668–672.)

Learning to read and write generates new rules within the language processing systems. These new rules significantly change the manner in which some operations are performed. This finding was studied, by comparing the performance of literate and illiterate persons in several tasks. It was found that illiterate individuals (1) had difficulties in repeating pseudowords, (2) were worse at memorizing pairs of phonologically related words compared to pairs of semantically related words, and (3) were unable to generate words according to a formal criterion. Illiterate persons use strategies that are good for semantic processing, but inadequate for phonological analysis, while literate individuals are able to use several parallel running strategies. (JINS, 1997, 3, 444–450.)