Working Memory and ADHD

    Working memory is short-term memory with instantaneous processing of day-to-day life moments. Because working memory is constantly being updated, it is important to understand how the brain focuses on crucial information and extricates it from irrelevant distractors. Previous research on working memory tends to view it as a single process in the brain. However, Dr.Vogel and his team conducted a research study where they hypothesized that visual working memory has several components that work together to ensure that task-irrelevant distractors aren’t processed into ongoing WM (working memory) representations while task-relevant distractors are. Attention Deficit Hyperactivity Disorder (ADHD) is characterized by inattention and executive dysfunction. According to the article, Your Brain’s GPS Is Glitchy: Why Working Memory Fails and How to Bolster It, recent research has shown that ADHD has strong ties with weak working memory allowing lots of distractors to slip in.

    In Dr.Vogel’s research, the team proposed a complex model of attentional capture for visual working memory consisting of two subcomponents: spatial capture and item-based capture. According to the model, spatial capture refers to a shift in attention to the location of the stimuli. Item-based capture refers to the formation of specific representations of the item in ongoing WM. Using EEG markers such as contralateral delay activity (CDA), distractor positivity (PD), and N2pc, the researchers determined which task distractors were processed into working memory based on their relevancy. As per the results, all incoming stimuli, regardless of relevance, were processed in spatial capture. However, only relevant stimuli were processed in item-based capture as seen by CDA activity and N2pc signals. Irrelevant stimuli triggered suppression mechanisms indicated by the presence of PD signals. The findings showed that visual working memory has an automatic component (spatial attention) and a voluntary component (item-based capture) that work together to ensure that working memory is useful in daily tasks.

    In the article on ADHD, the author discusses how executive functioning, which guides our purposeful efforts in day-to-day life, is often taxing for people with ADHD due to its reliance on working memory. This is because the strength of working memory determines how fast our brains can modify their actions, so the stronger the working memory, the easier it is to conduct intentional tasks. An analogy for working memory is a GPS. When our brain starts a new task, it often refers to its maps (the sensory information stored in working memory), to help form an understanding of the situation. Then, the visual images of non-verbal working memory are combined with verbal working memory as guidance and form our updated interpretation of the task. Like our GPS systems, it is important to process the relevance of information as it is presented to us to alter our plans and achieve maximum results. For those with ADHD, their brains are over-processing machines that cannot distinguish the relevance of the new information or determine what to do with it because too much information is presented all at once.

    Because ADHD is characterized by problems in working memory, it is beneficial to understand Dr.Vogel’s study and discuss its implications for ADHD research. Since Dr.Vogel’s team found two components to the working memory model, potential research studies can try to dissect which component is impaired in those with ADHD. Since an ADHD brain is characterized by overactivity and countless distractors, it can be hypothesized that a potential issue lies within the item-based capture of attentional control, known as the gating mechanism, which determines what distractors are allowed into the ongoing WM representation.

    In conclusion, studying and creating advanced models of working memory can be useful for ADHD research because those models can be used to understand the underlying mechanisms of ADHD.

References: 

 Alexander, Steph. “Your Brain’s GPS Is Glitchy: Why Working Memory Fails and How to Bolster It.” ADDitude, ADDitude, 14 Oct. 2024, www.additudemag.com/working-memory-powers-executive-function/.