ADHD & Working Memory

Studies show that people with ADHD tend to experience high-magnitude impairments in working memory. While this link is well-established in data, there is still significant disagreement about the extent to which this impairment reflects underlying neurological mechanisms that cause ADHD symptoms. 

According to Kofler et al., working memory “refers to the active, top-down manipulation of information held in short-term memory”. The concept can be understood as the small amount of information held in your brain while completing a task. It serves as a sort of copy and paste function, allowing your brain to transmit information. The dominant model used to understand working memory is from Baddeley (2007), in which working memory is composed of three distinct components: the central executive, ‘working’ element responsible for engaging with information stored in short-term memory; the phonological short-term memory, which bears responsibility for the temporary storage and rehearsal of verbal, auditory, language-based information; and visuospatial short-term memory, which is responsible for providing the temporary storage and rehearsal of information that cannot be verbally coded, especially visual and spatial information. Working memory is categorically responsible for the storage, rehearsal, and retrieval of information held in the short-term. 

People with ADHD are characterized by a process used in experiencing and processing information that is markedly different from neurotypical people. This means they tend to be more forgetful than people without the condition, and may be more challenged by tasks involving the use of short-term memory. ADHD can also influence the function of mechanisms used to store and retrieve information in long-term memory. A study from 2020 showed that ADHD has a noticeable impact on working memory in the majority of children with the condition. A research review conducted in 2013 demonstrated support for this impact lasting into adulthood. The frontal lobe of the brain, which is responsible for impulse control, attention, and memory, seems to undergo slower development in people with ADHD. This development seems to have more significant impacts on the central executive component of working memory than the phonological and visuospatial components. The effects of ADHD on these latter two components of working memory is less understood in research. Neurological effects of ADHD seem to be centrally effective in the executive functions of the frontal lobe, impacting memory, attention, and impulsiveness. 

Impairments in working memory are a significant cognitive characteristic of children with ADHD differentiating them from their neurotypical peers. A research review also demonstrated that children with ADHD tend to struggle in the development of long-term memory functions, which can cause impairment with long-term memory as adults if not provided with sufficient coping mechanisms. Research has also indicated a connection between visuospatial memory and impairments in relationships and academics, particularly reading and math. Working memory has a significant impact on intelligence and learning ability, which means people with ADHD tend to struggle in this area and may be unfairly assessed regarding their ability to learn. Working memory is also associated with the perception of time, which makes people with ADHD more likely to struggle with keeping a schedule. 

There are a number of strategies available to cope with working memory issues - none of which are a sufficient replacement for a treatment plan created in cooperation with a doctor or ADHD specialist, though they may improve day-to-day impacts. Certain ingredients have been suggested to negatively affect symptoms of ADHD, including caffeine, sodium benzoate, and FD&C Red No. 40 (an ingredient for food coloring). These should be avoided or substituted if possible as they may worsen the function of working memory. ADHD management tools such as calendars, task systems, and various apps may help regulate the fulfillment of responsibilities and reduce the stress resulting from working memory impairment. Cognitive Behavioral Therapy (CBT) has also been found to be extremely helpful for people with ADHD, as it works to modify thought patterns and allow management of emotions and behaviors. It has been found to help individuals who have ADHD with time management, goal-setting, task management, and executive function. Stimulant medication is often prescribed for the treatment of ADHD, and studies show it may strengthen the connectivity between the frontal cortex and other parts of the brain, improving working memory. Methylphenidate and Dexmethylphenidate in particular were found to have a positive impact on working memory when used with the supervision of a psychiatrist. Working memory impairment associated with ADHD can have lifelong effects, however, if the symptoms of this impairment are primarily noted in childhood, there is a chance they may improve or be alleviated altogether in the course of natural development. Working memory impairment can be effectively managed, especially with the help of a medical professional.

Sources:

Kofler, M. J., Singh, L. J., Soto, E. F., Chan, E. S. M., Miller, C. E., Harmon, S. L., & Spiegel, J. A. (11 September 2020). Working memory and short-term memory deficits in ADHD: A bifactor modeling approach. PubMed Central. Retrieved January 17, 2023, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7483636/#:~:text=Attention%2Ddeficit%2Fhyperactivity%20disorder%20 

Ortega, R., López, V., Carrasco, X., Escobar, M. J., García, A. M., Parra, M. A., & Aboitiz, F. (2020, May 8). Neurocognitive mechanisms underlying working memory encoding and retrieval in attention-deficit/hyperactivity disorder. Scientific Reports. Retrieved January 17, 2023, from https://www.nature.com/articles/s41598-020-64678-x