Attention-deficit/hyperactivity disorder (ADHD)
A diagnosis of ADHD is fundamentally clinical, based on clear and well-defined operational criteria, derived from classification systems such as the Diagnostic and Statistical Manual of Mental Health Disorders,2013. TOVA test has been used at Kids Neuro Clinic as initial and objective test for ADHD.
Executive functions (EFs) represent major functions that allow anticipation and the establishment of objectives, as well as the monitoring of results, by comparing them to the initial objective and reaching a final result. These abilities enable a human being to perceive stimuli in their environment, respond adequately, change direction in a flexible way, anticipate future objectives, consider the consequences and respond in an integrated way, using all these abilities to reach a final objective.
Working memory is an EF that is characterized as a complex cognitive mechanism to maintain, control and manipulate relevant information. It is considered the “online memory” that allows a person to understand what is happening at the moment. It is retained just for a few seconds, to enable understanding of the rest of the story or context. Deficits related to WM affect the ability to maintain control, and manipulate goal-related information.
Another important characteristic of ADHD from a neuropsychological point of view has been widely debated. Barkley’s theory proposes a deficit specifically in behavior inhibition. This view considers inhibitory processes as a core deficit in ADHD that secondarily disrupts other EF processes. Adaptive inhibition requires a multitude of interrelated processes, such as the monitoring of behavior, sustained attention, conflict detection and others, before the inhibition of the planned course of action and the behavior can be adjusted according to the moment.. A wide variety of neuropsychological tests indicate that ADHD children exhibit relatively weak, or sub-average, performances on various EFs.
Stimulants are the most commonly-used medications in the treatment of ADHD and their clinical efficacy is well established.