Executive dysfunctions have adverse effects on cognitive abilities and behaviour in both individual and social contexts. They can cause emotional dysregulation, manifested as chronic depression, anxiety, or overreactivity. A characteristic symptom of executive dysfunction is behaviour characterised by compulsive manipulativeness and imitative behaviour as the primary means of social interaction. When executive dysfunction is present, the accuracy of task performance decreases. The so-called dysexecutive syndrome is a clinical presentation of severe executive dysfunctions that are not associated with a specific disease or disorder and often occur following damage to the frontal lobes of the cerebral cortex.

Executive dysfunctions are observed in many mental illnesses, developmental disorders, psychiatric and affective disorders, behavioural disorders, and others. Schizophrenia is a mental disorder in which a person loses contact with reality due to disturbances in thought processes and perception. People with schizophrenia demonstrate deficits in response inhibition and cognitive flexibility. Cognitive deficits have also been demonstrated in people with bipolar disorder. In these cases, deficits are observed in strategic thinking, inhibitory control, working memory, attention, and initiation, which are independent of their affective state.

Executive dysfunction is a term that encompasses a range of cognitive, emotional, and behavioural difficulties. Executive dysfunctions may present as difficulties with time management, difficulties in carrying out tasks, a lack of or impaired cognitive and behavioural flexibility, and difficulties in maintaining sustained attention, all of which interfere with achieving goals. Executive dysfunctions are not included in the DSM or the ICD.

Symptoms of impaired executive functions include:

• Difficulty initiating a task
• Focusing either on details or on the overall picture, but not both simultaneously
• Inability to estimate the time required to complete a task
• Difficulty concentrating and being easily distracted
• Lack of sequential thinking
• Need for repeated instructions
• Difficulties in decision-making
• Slow processing speed

Consequences of impaired executive functions include:

• Socially inappropriate behaviour
• Inability to evaluate and anticipate the consequences of one’s actions
• Difficulties in forming abstract concepts
• Difficulty transitioning from fantasy to reality
• Difficulties with initiation and planning
• Difficulties in verbal fluency
• Inability to multitask
• Difficulties in processing, storing, and retrieving information
• Need for supervision
• Difficulties with fine motor skills
• Lack of empathy, loss of interest, and others

During childhood, executive dysfunctions are characteristic of various developmental disorders and specific conditions, including:

1. Attention-Deficit/Hyperactivity Disorder (ADHD)
In ADHD, attention, impulsivity, and activity level are affected, which often influence the learning process. Impairments in executive functions constitute a significant part of the symptoms of ADHD.

2. Autism Spectrum Disorders (ASD)
In autism spectrum disorders, the primary features are social deficits and pronounced cognitive impairments. Cognitive flexibility, attentional control during new tasks, planning, responses to social situations, regulation of social interactions, and both verbal and non-verbal behaviour are also impaired.

3. Intellectual and cognitive deficits
Children with intellectual and cognitive deficits have difficulties integrating thoughts and actions. They experience difficulties initiating tasks, focusing either on details or on the overall picture but not both simultaneously, evaluating the outcomes of their actions, and have a reduced ability to modify their behaviour and switch between tasks when necessary.

4. Fetal Alcohol Syndrome (FAS)
A condition such as fetal alcohol syndrome also affects executive functions, impacting learning, working memory, and other cognitive processes. Many children with FAS experience significant difficulties in everyday life due to the low level of development of their executive functions.

5. Anxiety and depressive disorders
Affective disorders such as depression and anxiety can influence executive functions, particularly through difficulties completing tasks, lack of or impaired cognitive and behavioural flexibility, difficulties maintaining attention, and others.

6. Bipolar affective disorder
Individuals with bipolar disorder demonstrate deficits in strategic thinking, inhibitory control, working memory, attention, and initiation, which are independent of their affective state.

7. Stress disorder
Children with stress disorders experience difficulties concentrating and are easily distracted. Memory impairments, reduced concentration, and other related difficulties are also observed.

Elements of executive dysfunction are also observed in Asperger syndrome, obsessive-compulsive disorder, and other conditions. Executive dysfunctions are present in ADHD, where the executive functions most commonly affected are attention and inhibition. In learning disorders, impairments are observed in self-monitoring and self-regulation, cognitive flexibility, organisation, and decision-making. In non-verbal learning disabilities, deficits are found in cognitive flexibility, adaptation to new situations, working memory, attentional control, and self-regulation. In autism spectrum disorders, impairments occur in cognitive flexibility, attentional control, responses to social situations, and regulation of social interactions. In Tourette syndrome, inhibition is predominantly impaired.

It is not known how frequently executive function impairments occur during childhood. What is known is that they are commonly observed in children with various developmental disorders. Clinical experience indicates that executive dysfunctions occur much more frequently than reported but are often misdiagnosed because they are expressed through a very broad range of symptoms.

Etiology of Executive Function Impairments

The etiology of executive function impairments is heterogeneous. This means that many neurocortical processes are involved in the executive function system. Damage to the connections between the prefrontal cortex and the hippocampus is considered a cause of executive dysfunction. Lesions of the frontal lobes may result from any form of acquired brain injury, such as stroke, tumour, encephalitis, or meningitis. Parkinson’s disease is a neurogenetic condition that causes executive dysfunction, whereas in Attention-Deficit/Hyperactivity Disorder (ADHD), subjectively identified symptoms include executive dysfunction as part of the clinical presentation of the disorder.

According to Friedman, the heritability of executive functions is among the highest compared with other mental functions. It is not clear why some children develop executive dysfunction. A number of studies provide the basis for considering the following possible factors:

• Genes and heredity
• Differences in brain functioning (brain disorders)
• Other impairments and disorders (Attention-Deficit/Hyperactivity Disorder, dyslexia, autism, and others)

Executive dysfunction is usually caused by structural or functional pathology of the frontal lobes. Executive functions are carried out by dynamic and flexible networks characterised by functional integration and effective connectivity. Recovery of executive functions following brain injury is possible.

Principles of Executive Function Assessment

1. All executive function tasks measure the capacity of other information-processing processes.
2. Every assessment of information-processing processes and/or academic achievement is an indirect measure of executive functions.
3. There is no single assessment that can be successfully used to measure one executive function.
4. The nature of executive functions encompasses a broad range of processes that are demonstrated only in real-life situations.
5. Executive functions should be assessed in relation to other abilities and skills.

A comprehensive and multidimensional assessment of executive functions is necessary to obtain the best possible understanding of a child’s functioning.