Hello my zebras and spoonies! Thanks for stopping by and visiting with me today. I’m glad that you’re here.
I’m going to talk about the way that the ADHD brain engages with the world. But in order to better do that, we first need to look at how the neurotypical brain functions.
All our memories begin with a sensory input. Something happens in our environment, that’s the input. This input triggers what’s called sensory memory. That in and of it self is a complex topic. There are seven senses that are scientifically agreed upon and numerous others that are still being debated about. Those seven accepted senses are:
- Sight (Visual)
- Hearing (Auditory)
- Smell (Olfactory)
- Taste (Gustatory)
- Touch (Tactile)
- Vestibular (Movement)
- Proprioception (Body Position)
A broadly acceptable definition of a sense for neurologists would be a group of sensory cells that respond to a specific physical phenomenon, and that correspond to a particular region of the brain where the signals are received and interpreted. Those signals being received and interpreted is what is called sensory memory. This only lasts a fraction of a second.
Once something comes into the brain’s sensory memory, the brain will decide whether or not to direct attention towards that sensory input or not. If attention is assigned to the sensory input, that sensory memory moves into working memory. If attention is not assigned, the sensory input is not consciously perceived by the person and does not enter memory. Whether or not something is assigned attention is not a conscious choice. This is a process that our subconscious brain undertakes in a continuous fashion. This is why we can become used to wearing our clothing and not actively think about the way they feel against our bodies all day long. It’s also why sounds can become background noise that you no longer attend to.
Working memory is our short term memory. It has three key aspects: limited capacity, limited duration and encoding. The limited capacity and duration are key features when discussing the manner in which working memory functions. We can only process a certain amount of information at a time and if distracted can only hold that information in our working memory for a short period of time. Encoding is the process of transitioning information from working memory to long term memory. However, it’s important to note that our brains handle different kinds of information in different ways. There are three different systems for different types of information within our working memory:
- Central Executive
- Visuospatial Sketchpad (inner eye)
- Phonological Loop
- Phonological Store (inner ear)
- Articulatory control process (inner voice)
The Central Executive system is the boss of our working memory. This is the part of working memory that allocates where data goes. It also deals with cognitive tasks such as mental arithmetic and problem-solving. The visuospatial sketchpad is a component of working memory model which stores and processes information in a visual or spatial form. The visuospatial sketchpad is used for navigation. The phonological loop is a component of working memory model that deals with spoken and written material. It is subdivided into the phonological store and the articulatory process. Phonological Store (inner ear) processes speech perception and stores spoken words we hear for 1-2 seconds. Articulatory control process (inner voice) processes speech production, and rehearses and stores verbal information from the phonological store.
If working memory is interrupted the person forgets the information that was being stored in their working memory because it wasn’t encoded into long term memory. This is why most people have a difficult time recalling other people’s names. When you are introduced to someone new, you are rarely given the time to encode their name to your long term memory. Instead, you are usually bombarded with additional information that exceeds the capacity of your working memory which makes it difficult to encode the name to long term memory.
Information between long term and working memory is a constant flow of traffic. As new information comes in, it is encoded and stored as memories in long term memory. When we recall information, it is pulled into our working memory where we can contemplate and manipulate that information; often creating additional or modified long term memories. This is how the process of associative thinking works.
That’s how things work when you have a neurotypical brain. But things are different when you have ADHD. To look at those differences, let’s start back at the beginning again.
All our memories begin with a sensory input. Something happens in our environment, that’s the input. This input triggers what’s called sensory memory. But for most people with ADHD, there are sensory processing disorders. Sensory processing disorder is a condition in which the brain has trouble receiving and responding to information that comes in through the senses. This often means that the sensory memory is never formed or is distorted. This can effect any of the seven body senses. Sensory processing disorder is often down played, but when you consider the way that the brain collects and processes information to create memories it become obvious how much this impacts those with the disorder.
Once something comes into the brain’s sensory memory, the brain will decide whether or not to direct attention towards that sensory input or not. If attention is assigned to the sensory input, that sensory memory moves into working memory. If attention is not assigned, the sensory input is not consciously perceived by the person and does not enter memory. ADHD is a disorder of attention regulation. Often times, attention is assigned to everything that is coming in and the person is flooded with sensory information. Other times, in a state of hyper focus, attention is assigned to only a narrow group while discarding all other sensory information.
When attention is assigned equally to all incoming sensory information, working memory quickly becomes overwhelmed and the person looses the ability to encode new memories because the input exceeds the brains working memory capacity. During times of hyper focus, much of the sensory information is not being sent to working memory and thus doesn’t have the chance to become encoded into memory. In both cases, the result is that much of the sensory input presented to a person with ADHD is not encoded into memory.
Those with ADHD often have comorbidities of learning disorders, dyscalculia and dyslexia. The cause for this becomes evident when considered in the context of how memory works. It’s within our working memory that we deal with cognitive tasks such as mental arithmetic, spatial relations and language. When this memory is being overwhelmed with irrelevant sensory information it becomes difficult to hold the desired information within the limited capacity of the working memory’s space. When hyper focus is engaged and new input is denied it becomes difficult to engage with conversation or navigate. Our working memory is our active brain. If it is given too little or too much sensory information, it is unable to complete the task. Now consider the way that working memory is used to access long term memory. If the working memory is over whelmed of being blocked with hyper focus, it becomes difficult for the brain to access long term memories.
All of this means that individuals with ADHD have impaired working memory that results in difficulties tracking conversations, making new information, recalling memories and making decisions. These difficulties all stem from the brains inability to regulate it’s attention to sensory information.