**2.4. Executive functions and cerebellum**

The cerebellum is a major but often a less well-understood component of the executive functions system. Cerebellum reaches its size at about 11 years for girls and 15 years for boys and is as important as regions that control executive function in early childhood [44]. Cerebellum gains maturity during motor control, emotional processing, and adolescence period and plays a central role in high cognitive functions. The cortico-ponto-cerebellar network works intensively in the timing and ordering of requests such as verbal working memory and executive aspects of visual and verbal analysis (**Figure 6**) [45]. In addition, it is also known

**Figure 5.** Prefrontal cortex and parietal cortex.

distinguished and identified the participants with learning disability the most accurately from their typically developing peers. Similarly, the meta-analysis of 13 researchers comparing children with learning disorder and children with typical development has shown that the overall impact dimension which was measured by planning, organizing, strategy development, attention to detail, and recall tests for executive functions is moderate. Although verbal and visual working memory seems to be effective, verbal working memory has been shown to be more effective than visual working memory [53–56]. It is seen that the difference between the subjects with reading difficulty and typical readers increases with age. Overall, findings suggest a strong association between learning disability and executive functions [49, 57, 58]. Some studies have investigated the difficulties of executive functioning in subtypes of reading disorders. In particular, researchers compared the difficulty of reading a word with the difficulty of understanding reading. For example, in one study, adolescents were categorized as difficulty in reading a word, difficulty in isolated understanding, or typical reading achievement. Working memory and planning (when controlling attention, coding, fluency, and vocabulary) make a meaningful contribution to understanding what is being read but not word recognition. Findings of difficulty in planning have continued in adolescents who had difficulty understanding the reading even after controlling the accompanying ADHD and phonological processing ability. Although reading disorders are often accompanied by ADHD, these studies show that executive functioning difficulties may also occur in individuals without ADHD but reading-comprehension difficulties, and that the difficulties of strate-

Executive Functions and Neurology in Children and Adolescents

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gic planning are closely related to the difficulties of understanding [58–60].

During the individual assessment, a child's approach to a mission can reveal the strengths and weaknesses of executive functions. While some tests are designed to evaluate executive functions, each component of the evaluation process may provide different information about

1. Almost every test contains executive functions. The executive function is related to many things, and it is impossible to draw conclusions from an evaluation alone. For example, even completing the most standard scales requires some planning, strategy, or impulse control. The opposite is also true; most of the tests described as primary "executive functioning evaluation tool" include other cognitive processes. This is called "task impurity" [61]. As a result, other tests (including intellectual work and academic achievement) and behavioral observations also provide information about executive functions. It is impor-

**2.** Standardization can remove features of executive functions. The structure of an ironically standardized test may reduce the requirements of some of the aspects of executive functions [62, 63]. Most of the standardized tests contain clear instructions and scoring. This

tant to be aware of these elements and their role in evaluation and definition.

**4. Evaluation of executive functions**

**4.1. Key issues in evaluating executive functions**

executive functions and disorders.

**Figure 6.** Prefrontal cortex and cerebellum.

that cerebellum has a modulating effect on emotional, cognitive, and regulatory capacities. However, cerebellar lesions do not appear to explain the impairment executive functions alone. It is thought that when executive dysfunctions are accompanied by cerebellar dysfunction, executive functions are impacted [46].
