Impact of literacy on the functional connectivity of vision and language related networks.

Learning to read leads to functional and structural changes in cortical brain areas related to vision and language. Previous evidence suggests that the Visual Word Form Area (VWFA), a region devoted to the recognition of letter strings in literate persons, acts as an interface between both systems. While different studies have performed univariate analyses to study the effects of literacy on brain function, little is known about its impact on whole functional networks, especially when literacy is acquired during adulthood. We investigated functional connectivity in three groups of adults with different literacy status: illiterates, ex-illiterates (i.e., who learned to read during adulthood), and literates (i.e., who learned to read in childhood). We used a data-driven, multivariate whole brain approach (Independent Component Analysis [ICA]) combined with a region of interest (ROI) analysis in order to explore the functional connectivity of the VWFA with four ICA networks related to vision and language functions. ICA allowed for the identification of four networks of interest: left fronto-parietal, auditory, medial visual and lateral visual functional networks, plus a control right fronto-parietal network. We explored the effects literacy on the connectivity between the VWFA and these networks, trying furthermore to disentangle the roles of reading proficiency and age of acquisition (i.e., literacy status) in these changes. Results showed that functional connectivity between the VWFA and the left fronto-parietal and lateral visual networks increased and decreased, respectively, with literacy. Moreover, the functional coupling of the VWFA and the auditory network decreased with literacy. This study provides novel insights in the mechanisms of reading acquisition and brain plasticity, putting to light the emergence of the VWFA as a bridge between language and vision. Further studies are required to characterize the interplay of proficiency and age of reading acquisition, and its relevance to models of brain plasticity across lifespan.

Differences in factors influencing the use of eRehabilitation after stroke; a cross-sectional comparison between Brazilian and Dutch healthcare professionals.

BACKGROUND: To improve the use of eRehabilitation after stroke, the identification of barriers and facilitators influencing this use in different healthcare contexts around the world is needed. Therefore, this study aims to investigate differences and similarities in factors influencing the use of eRehabilitation after stroke among Brazilian Healthcare Professionals (BHP) and Dutch Healthcare Professionals (DHP). METHOD: A cross-sectional survey study including 88 statements about factors related to the use of eRehabilitation (4-point Likert scale; 1-4; unimportant-important/disagree-agree). The survey was conducted among BHP and DHP (physical therapists, rehabilitating physicians and psychologists). Descriptive statistics were used to analyse differences and similarities in factors influencing the use of eRehabilitation. RESULTS: ninety-nine (response rate 30%) BHP and 105 (response rate 37%) DHP participated. Differences were found in the top-10 most influencing statements between BHP and DHP BHP rated the following factors as most important: sufficient support from the organisation (e.g. the rehabilitation centre) concerning resources and time, and potential benefits of the use of eRehabilitation for the patient. DHP rated the feasibility of the use of eRehabilitation for the patient (e.g. a helpdesk and good instructions) as most important for effective uptake. Top-10 least important statements were mostly similar; both BHP and DHP rated problems caused by stroke (e.g. aphasia or cognitive problems) or problems with resources (e.g. hardware and software) as least important for the uptake of eRehabilitation. CONCLUSION: The results indicate that the use of eRehabilitation after stroke by BHP and DHP is influenced by different factors. A tailored implementation strategy for both countries needs to be developed.

Correction to: Differences in factors influencing the use of eRehabilitation after stroke; a cross-sectional comparison between Brazilian and Dutch healthcare professionals.

An amendment to this paper has been published and can be accessed via the original article.

Timing the impact of literacy on visual processing.

Learning to read requires the acquisition of an efficient visual procedure for quickly recognizing fine print. Thus, reading practice could induce a perceptual learning effect in early vision. Using functional magnetic resonance imaging (fMRI) in literate and illiterate adults, we previously demonstrated an impact of reading acquisition on both high- and low-level occipitotemporal visual areas, but could not resolve the time course of these effects. To clarify whether literacy affects early vs. late stages of visual processing, we measured event-related potentials to various categories of visual stimuli in healthy adults with variable levels of literacy, including completely illiterate subjects, early-schooled literate subjects, and subjects who learned to read in adulthood (ex-illiterates). The stimuli included written letter strings forming pseudowords, on which literacy is expected to have a major impact, as well as faces, houses, tools, checkerboards, and false fonts. To evaluate the precision with which these stimuli were encoded, we studied repetition effects by presenting the stimuli in pairs composed of repeated, mirrored, or unrelated pictures from the same category. The results indicate that reading ability is correlated with a broad enhancement of early visual processing, including increased repetition suppression, suggesting better exemplar discrimination, and increased mirror discrimination, as early as ∼ 100-150 ms in the left occipitotemporal region. These effects were found with letter strings and false fonts, but also were partially generalized to other visual categories. Thus, learning to read affects the magnitude, precision, and invariance of early visual processing.

Learning to read improves the structure of the arcuate fasciculus.

The acquisition of literacy results from an effortful learning process that leads to functional changes in several cortical regions. We explored whether learning to read also leads to anatomical changes within the left intrahemispheric white matter pathways that interconnect these regions. Using diffusion tensor imaging tractography, we compared illiterates with ex-illiterates who learned to read during adulthood and literates who learned to read during their childhood. Literacy related to an increase in fractional anisotropy and a decrease in perpendicular diffusivity in the temporo-parietal portion of the left arcuate fasciculus. The microstructure within this pathway correlated with the reading performance and the degree of functional activation within 2 dominant brain regions involved in reading: The Visual Word Form Area in response to letter strings, and the posterior superior temporal cortex in response to spoken language. Thus, the acquisition of literacy is associated with a reinforcement of left temporo-parietal connections whose microstructure predicts overall reading performance and the functional specialization of the Visual Word Form Area. This anatomical magnetic resonance imaging marker may be useful to predict developmental reading disorders.

Determinants of participation of youth with acquired brain injury: A systematic review.

OBJECTIVES: Participation is considerably restricted in children and adolescents with acquired brain injury (ABI) as compared to their healthy peers. This systematic review aims to identify which factors are associated with participation in children and adolescents with ABI. METHODS: A systematic search in Medline and various other electronic databases from January 2001-November 2014 was performed. All clinical studies describing determinants of participation at least 1 year after the diagnosis of ABI by means of one or more pre-defined instruments in patients up to 18 years of age were included. Extracted data included study characteristics, patient characteristics, participation outcome and determinants of participation (categorized into: health conditions (including characteristics of ABI), body functions and structures, activities, personal factors and environmental factors). The methodological quality of the studies was evaluated based on three quality aspects (selection, information and statistical analysis bias) and scored as low, moderate or high. RESULTS: Eight studies using an explicit participation outcome measure were selected after review, including a total of 1863 patients, with a follow-up ranging from 1 up to 288 months. Three studies included patients with a traumatic or a non-traumatic brain injury (TBI or NTBI) and five studies with only TBI patients. Factors consistently found to be associated with more participation restrictions were: greater severity of ABI, impaired motor, cognitive, behavioural and/or sensory functioning, limited accessibility of the physical environmentand worse family functioning. Fewer participation problems were associated with a supportive/nurturing parenting style, higher household income, acceptance and support in the community and availability of special programmes. The overall methodological quality of the included studies was high in two and moderate in six studies. CONCLUSION: This systematic review shows that only a few, moderate quality, studies on the determinants of participation after paediatric ABI using recommended explicit measurement instruments are available. Various components of the ICF model: health condition, body functions and structures and environmental factors were consistently found to be associated with participation. More methodologically sound studies, using the recommended explicit outcome measures, a standardized set of potential determinants and long-term follow-up are suggested to increase the knowledge on participation in children and youth with ABI.

Neuropsychological rehabilitation, neuroimaging and neuroplasticity: A clinical commentary.

Initial brain imaging studies on recovery of motor functioning after stroke suggested their potential prognostic value in neurorehabilitation. However, the value of brain imaging in documenting brain changes associated with cognitive and behavioral treatment effects seem less likely. Also, neuroimaging studies at that time seem to have little, if any, value for treatment planning. Advances in neuroimaging technology are beginning to challenge these initial impressions. In this clinical commentary, we propose that advances in the field of neuroimaging have relevance for the future development of neuropsychological rehabilitation. Neuropsychological rehabilitation is entering a new era that involves collaboration with neuroimaging and associated studies on neuroplasticity. We recognize that this may seem "aspirational" rather than practical in most rehabilitation settings. However, we provide examples of how this can be achieved as illustrated by collaborative efforts of clinicians and scientists in the SARAH Network of Rehabilitation Hospitals in Brazil. We also review selective papers on neuroplasticity, spontaneous recovery and diaschisis that have relevance for research which will expand and further develop the field of neuropsychological rehabilitation.

Apolipoprotein E genotype and cerebral palsy.

AIM: Apolipoprotein E (APOE, protein; [ApoE, gene]) is a lipid transport protein abundantly present in brain cells. We investigated whether the APOE genotype is associated with cerebral palsy (CP) and whether patients with CP with comorbid conditions and more severe neurological deficits are likely to have a particular genotype. METHOD: In a cross-sectional study, 243 individuals with spastic CP (135 males, 108 females; mean age at data collection 11 year ([SD 6y 7mo], 34% with hemiplegia, 37% with diplegia, 29% with triplegia/tetraplegia; 44% with mild motor involvement), 31% with moderate motor involvement, 25% with severe motor involvement, were compared with healthy individuals matched by age, race, and sex to analyse the association between APOE genotype and the incidence of CP. Associations between the APOE genotype and the incidence of comorbidities and neurological deficits were studied in the group with CP. RESULTS: The APOE epsilon2epsilon3 genotype was significantly more prevalent in the group with CP (11%) than the comparison group (5%) (odds ratio [OR] 2.8; 95% confidence interval [CI] 1.01-7.66). The presence of the epsilon2 allele raised the probability of having CP (OR 3.2; 95% CI 1.27-8.27). The presence of ApoE epsilon4 was not significantly different among groups. No relation was found between APOE genotype and severity of neurological deficit or distribution of motor involvement. Four patients with CP presented the epsilon4epsilon4 genotype, and all exhibited epilepsy and microcephaly. Eleven of 12 individuals with CP and macrocephaly carried the epsilon3epsilon3 genotype. INTERPRETATION: A higher prevalence of the APOE epsilon2 genotype was found among those with CP. The association of microcephaly and epilepsy with the epsilon4epsilon4 genotype and the association of macrocephaly with epsilon3 demand further investigation.

Performance of a Brazilian sample on the Portuguese translation of the BNI Screen for Higher Cerebral Functions.

INTRODUCTION: The Barrow Neurological Institute (BNI) Screen for Higher Cerebral Functions (BNIS) has been translated into several languages and found useful in evaluating multiple domains of cognitive and affective dysfunction, particularly in neuro-rehabilitation settings. Normative data from countries with high literacy rates have reported strikingly similar mean level of performance scores on this test, with age typically correlating higher with total score performance than education. In the present study, we obtain convenience sample normative data from a native Brazilian population on a Portuguese translation of the BNIS (i.e., BNIS-PT). METHOD: The BNIS was translated into Portuguese by two native speaking Portuguese neuropsychologists who were also fluent in English. It was then administered to 201 normally functioning native Brazilian individuals who varied considerably in age and formal educational training. RESULTS: The mean BNIS total score was similar to what previous studies reported, but primarily in younger adults with at least 12 years of formal education. In this Brazilian sample, the correlation of educational level and BNIS total score was r = .68, p < .001. The correlation of age and BNIS total score was r = -.36, p < .001. This is the opposite pattern to that observed in previous standardization studies. The strong correlation of education with performance in various subtests was observed in all age groups (ages ranging from 15 to 85 years). CONCLUSION: This standardization study provides guidelines for calculating expected average performance levels on the BNIS-PT for Brazilian individuals with varying degrees of age and education. Educational level positively correlated with test performance on the BNIS-PT and was repeatedly observed to overshadow the effects of age, suggesting its important role in the development of higher cerebral functions in multiple domains in a Brazilian sample of normally functioning individuals.

Magnetic resonance imaging (MRI) findings and neuropsychological sequelae in children after severe traumatic brain injury: the role of cerebellar lesion.

We studied the relationships between magnetic resonance imaging (MRI) findings and neuropsychological sequelae in children after severe traumatic brain injury. Twenty-three children ages 7-13 years underwent MRI assessment of brain lesion topography and volume and neuropsychological evaluations, more than 1 year after sustaining severe traumatic brain injury. Most children had lesions to the corpus callosum and frontal lobes. Total lesion volume and extent of cerebral atrophy did not impact on the neuropsychological evaluation. Additional relationships were observed: left frontal lesions with lower semantic verbal fluency, right occipital lesions with lower visual recognition task scores, dyscalculia with cerebellar lesions, and cerebellar damage with lower cognitive performances and lower visual recognition memory. This study demonstrates the significance of the cerebellum's role in neuropsychological outcomes after traumatic brain injury and the importance of the lesion depth classification in predicting functional results.

Differing Connectivity of Exner's Area for Numbers and Letters.

There is a growing body of evidence indicating a crucial role of Exner's area in (hand-) writing symbolic codes such as letters and words. However, a recent study reported a patient with a lesion affecting Broca's and Exner's area, who suffered from severe peripheral agraphia for letters but not for Arabic digits. The authors suggested a speculative account postulating differential connectivity of Exner's area for numbers and letters in order to explain this dissociation. In the present study, we evaluated this account, employing atlas-based tractography for the patient's anatomy, deterministic fiber-tracking as well as an automated toolkit to investigate the connectivity of Exner's area in healthy adults. In particular, fiber pathways connecting Exner's area with areas associated with language processing (e.g., the arcuate fascicle, ventral pathways encompassing the external/extreme capsule system) reached the inferior part of Exner's area, while fronto-parietal fibers (e.g., the superior longitudinal fascicle) connected the upper part of Exner's area with the intraparietal sulcus typically involved in number processing. Our results substantiated the differential connectivity account for Exner's area by identifying the neural connections between fiber tracts and cortex areas of interest. Our data strongly suggest that white matter connectivity should be taken into account when investigating the neural underpinnings of impaired and intact human cognition.

Literacy breaks mirror invariance for visual stimuli: a behavioral study with adult illiterates.

The ability to recognize 2 mirror images as the same picture across left-right inversions exists early on in humans and other primates. In order to learn to read, however, one must discriminate the left-right orientation of letters and distinguish, for instance, b from d. We therefore reasoned that literacy may entail a loss of mirror invariance. To evaluate this hypothesis, we asked adult literates, illiterates, and ex-illiterates to perform a speeded same-different task with letter strings, false fonts, and pictures regardless of their orientation (i.e., they had to respond "same" to mirror pairs such as "iblo oldi"). Literates presented clear difficulties with mirror invariance. This "mirror cost" effect was strongest with letter strings, but crucially, it was also observed with false fonts and even with pictures. In contrast, illiterates did not present any cost for mirror pairs. Interestingly, subjects who learned to read as adults also exhibited a mirror cost, suggesting that modest reading practice, late in life, can suffice to break mirror invariance.

Illiteracy: the neuropsychology of cognition without reading.

Illiterates represent a significant proportion of the world's population. Written language not only plays a role in mediating cognition, but also extends our knowledge of the world. Two major reasons for illiteracy can be distinguished, social (e.g., absence of schools), and personal (e.g., learning difficulties). Without written language, our knowledge of the external world is partially limited by immediate sensory information and concrete environmental conditions. Literacy is significantly associated with virtually all neuropsychological measures, even though the correlation between education and neuropsychological test scores depends on the specific test. The impact of literacy is reflected in different spheres of cognitive functioning. Learning to read reinforces and modifies certain fundamental abilities, such as verbal and visual memory, phonological awareness, and visuospatial and visuomotor skills. Functional imaging studies are now demonstrating that literacy and education influence the pathways used by the brain for problem-solving. The existence of partially specific neuronal networks as a probable consequence of the literacy level supports the hypothesis that education impacts not only the individual's day-to-day strategies, but also the brain networks. A review of the issues related to dementia in illiterates is presented, emphasizing that the association between the education level and age-related cognitive changes and education remains controversial. The analysis of the impact of illiteracy on neuropsychological test performance represents a crucial approach to understanding human cognition and its brain organization under normal and abnormal conditions.

How learning to read changes the cortical networks for vision and language.

Does literacy improve brain function? Does it also entail losses? Using functional magnetic resonance imaging, we measured brain responses to spoken and written language, visual faces, houses, tools, and checkers in adults of variable literacy (10 were illiterate, 22 became literate as adults, and 31 were literate in childhood). As literacy enhanced the left fusiform activation evoked by writing, it induced a small competition with faces at this location, but also broadly enhanced visual responses in fusiform and occipital cortex, extending to area V1. Literacy also enhanced phonological activation to speech in the planum temporale and afforded a top-down activation of orthography from spoken inputs. Most changes occurred even when literacy was acquired in adulthood, emphasizing that both childhood and adult education can profoundly refine cortical organization.