Attention Deficit Hyperactivity Disorder

Attention Deficit Hyperactivity Disorder (ADHD)

Definition and Diagnostic Criteria

Attention Deficit Hyperactivity Disorder (ADHD) criteria have been established by the American Psychiatric Association (DSM-5-TR®, 2022) and the World Health Organization (ICD-11, 2022). These criteria are developed by a panel of experts, including researchers and clinicians, based on scientific evidence to create precise diagnostic guidelines.

ADHD is a neurologically based disorder. It is not caused by intellectual delays, sensory deficits (e.g., vision or hearing impairments), social issues, lack of effort, or motivation on the part of the individual. It is also not due to inadequate parenting, temporary immaturity, or emotional disorders. Consequently, simply expecting the child or adult to try harder will not eliminate or correct the disorder.

ADHD is a chronic condition that persists throughout life. According to scientific literature, 3–6% of children and adults may have ADHD, yet less than a third of them receive a formal diagnosis.

What is ADHD?

ADHD is a cluster of symptoms that significantly disrupt social (family and peer relationships), academic, or professional functioning. ADHD can be categorized into three major subtypes:

1. Predominantly Inattentive Type

Individuals with attention deficits struggle to stay focused on tasks (e.g., listening in class, completing homework, reading, or following a conversation) for extended periods (15 minutes or more). Their thoughts often wander into daydreams. Children and adults with this subtype are easily distracted by their surroundings (e.g., the sound of a car, a pencil dropping, or the ticking of a clock).

2. Predominantly Hyperactive-Impulsive Type

• Hyperactivity: Individuals with this subtype find it challenging to stay still. They often fidget, squirm, and have difficulty sitting still, playing, or completing tasks quietly. As a result, they frequently get up even in situations where staying seated is required (e.g., in class or during meetings). They may also struggle to stop talking, which can sometimes make them appear socially immature.
• Impulsivity: These individuals act hastily, often without thinking. They may start tasks or activities without fully understanding the instructions and struggle to wait their turn (e.g., in conversations, games, or lines). They may also blurt out thoughts they later regret.

3. Combined Inattentive and Hyperactive-Impulsive Type

These individuals exhibit symptoms of both inattention and hyperactivity-impulsivity.

Origins of ADHD

ADHD is a neurodevelopmental disorder with a neurological origin, linked to neurochemical imbalances in brain regions responsible for self-regulation, sustained alertness, and attention. Evidence suggests a strong hereditary component. ADHD can also arise following encephalitis, traumatic brain injury, or premature birth.

ADHD and Learning Disorders

ADHD is a significant cause of learning difficulties and can lead to substantial challenges in social integration, both in school and the workplace. Depending on the severity and nature of the deficit, ADHD can delay academic progress in areas such as reading, writing, and mathematics.

Attention is a key gateway to learning. Without it, individuals cannot process, analyze, understand, or remember information effectively. Children with ADHD may miss foundational academic skills, which are essential for acquiring new knowledge. If ADHD is not properly identified and addressed with tailored intervention plans, individuals may underperform relative to their true potential.

Unfortunately, many children, adolescents, and even university students face academic challenges due to undiagnosed ADHD. Similarly, workers with ADHD may fail to reach their full potential.

The Role of Neuropsychology in Identifying ADHD

Neuropsychologists use structured interviews and questionnaires aligned with the DSM-5-TR and ICD-11 criteria to identify ADHD symptoms. These symptoms must be present in at least two settings (e.g., home, school, or work) and must have emerged before the age of 12. Importantly, symptoms should not be attributable to intellectual delays, psychiatric conditions, or emotional disorders, though these can coexist with ADHD.

A comprehensive neuropsychological evaluation can clarify the nature of attention deficits. Attention comprises various components, some of which may function well while others are impaired in individuals with ADHD. Identifying specific deficits is crucial, as they may require different interventions. These components include:

• Selective Attention: The ability to focus on relevant information (e.g., paying attention in class) while ignoring irrelevant stimuli.
• Sustained Attention: The capacity to maintain focus on a single task (e.g., listening to a teacher, reading, or doing homework) over time.
• Divided Attention: The ability to manage multiple tasks simultaneously (e.g., listening to a teacher while following an exercise in a workbook).

Differentiating ADHD from Other Disorders

Neuropsychological evaluations can also identify other conditions that often coexist with ADHD but might otherwise go unnoticed:

• Learning Disorders: ADHD can impair academic success. It is crucial to determine whether academic difficulties are due to ADHD or another learning disorder, such as dyslexia. Approximately 50% of individuals with dyslexia also have ADHD.

• Executive Function Disorders: Many individuals with ADHD struggle with planning and organization, which constitute learning disorders in their own right. For example, they may find it challenging to structure and organize tasks, plan schedules, or manage time effectively.

Intervention and Support

Once ADHD is formally identified, neuropsychological assessments can guide the development of tailored intervention plans. These interventions address ADHD-related challenges at home, school, and work, as well as secondary difficulties, such as academic delays.

Through neuropsychological evaluations, individuals with ADHD can access appropriate support and resources, helping them reach their full potential.