The current diagnosis of attention deficit hyperactivity disorder (ADHD) is based on history, clinical observation, and behavioral tests. There is a high demand to find biomarkers for the diagnosis of ADHD. The aim of this study is to analyze the serum profiles of several biomarkers, including homocysteine (Hcy), vitamin B12, vitamin D, ferritin, and iron, in a cohort of 133 male subjects (6.5–12.5 years), including 67 individuals with an ADHD diagnosis based on DSM-V criteria and 66 age-matched healthy boys (healthy controls, HC). Assessments for ADHD included the Iowa Conners’ Teacher Rating Scale (CPRS) and the ADHDT test, as well as cognitive assessments using the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the TROG-2 language comprehension test. Hcy and iron were quantified using spectrophotometry, while vitamin B12 and total 25-hydroxy vitamin D levels were determined using an electrochemiluminescence immunoassay (ECLIA) and ferritin was measured using a particle-enhanced immunoturbidimetric assay. The results showed significantly increased Hcy levels and decreased vitamin B12 levels in ADHD patients compared to HCs. Multiple logistic regression analysis indicated that Hcy is a potential prognostic indicator for ADHD. These results suggest that elevated homocysteine and decreased vitamin B12 may serve as markers for the diagnosis and prognosis of ADHD.

Background/Objectives: Dyslexia, a prevalent reading disorder, substantially affects children’s educational and social development. Early diagnosis is essential for timely intervention; however, Serbia lacks a standardized instrument for assessing dyslexia in primary school children. This study aimed to evaluate the reliability and predictive validity of the Dyslexia Screening Test-Junior (DST-J), which was adapted for the Serbian language and cultural context. Methods: The study sample comprised 647 children from the general population, aged 6 years and 6 months to 11 years and 5 months, along with 30 children of comparable age exhibiting reading difficulties. The assessment of validity was based on the at-risk quotient, predictive validity, and test–retest reliability. Results: Significant differences in at-risk quotient (ARQ) scores were found between children with and without dyslexia (t = 14.90, p < 0.001), with boys, particularly those aged 9.6 to 10.5 years, having higher risk scores than girls. Internal consistency was acceptable (Cronbach’s α = 0.704), and construct validity was confirmed by correlations with external measures, which explained 44% of the variance (R² = 0.44; p < 0.01). Predictive validity was high for key subtests such as rapid naming and phonemic segmentation, reaching maximum accuracy (sensitivity and specificity = 1). Conclusions: The findings indicate that the adapted DST-J is effective in identifying dyslexia risk among Serbian primary school children. The innovation of this study lies in the cultural adaptation of the DST-J, with future research directed towards refining this instrument and exploring additional diagnostic criteria to enhance its accuracy and inclusivity.

The main goal of this research was to study the correlates of school underachievement and to sketch the possible profile of the gifted underachiever. The study was conducted on a sample of high school students in Belgrade (N = 434). The subjects were administered a battery of ability tests and asked to self-estimate their intelligence. On the basis of ability test and school achievement data, the subjects were classified into three groups: gifted underachievers (N1 = 26), gifted students (N2 = 81), and others (N3 = 332). The results of ANOVAs indicate that these three groups differ significantly on the dimensions of Attitudes towards school: academic self-perception, attitudes toward teachers, assessment goals, and motivation and self-regulation. Also, significant between-group differences emerge on the following dimensions of self-concept: assessment of ability, assessment of achievement, and academic self-confidence. These dimensions show the highest correlation with the canonical function that efficiently discriminates between underachievers and gifted students (canonical correlation coefficient = .70, performance of classification = 91.6%). Students who do not realize their potential in school, although they consider themselves to be equally intelligent as gifted students, do not draw their confidence and self-esteem from academic achievement. Gifted underachievers evaluate educational goals as less important and are not motivated to make an effort in school. Also, they are likely to come into conflict with teachers in order to challenge their authority. These results suggest that being an underachiever is a 'choice of will', rather than the unwilling result of difficulties in the environment, psychological problems or underdeveloped meta-cognitive skills, but an alternative interpretation is also plausible. The roots of this hypothetical choice are examined with reference to the educational system and its possible effects of 'normalization'.

The main goal of this work is to examine how different theoretical points of view (constructivist, co-constructivist and dynamical systems theory) explain the mechanism of creating new cognitive competencies within social interactions and, on the other hand, to show that there is some evidence that partly cannot be explained by the conceptual framework of these approaches. All three approaches give complementary explanations from different but reciprocal points of view showing different aspects of social interaction that leads to greater achievement in the subsequent individual cognitive functioning. Constructivist approach focuses on the importance of normative facts that create a logical imbalance and are often produced within a situation of interaction, co-constructivist framework emphasizes the importance of thinking which is embedded in language and socio-cultural exchange, and dynamical systems theory seeks to describe interaction in the concept of bifurcation. These approaches are less capable of explaining the findings that cognitively more competent children who enter the interaction with the less competent but more confident partners achieve lower results than in pretest. Question is asked whether concepts such as normativity and discourse can be helpful in explaining this phenomenon and whether they play some sort of role in mechanisms of cognitive development. .