Brain Capacity

What is Brain Capacity?

Brain capacity and function are incredibly dynamic, influenced by both innate potential and external factors such as health, environment, and experiences. While the brain has an extraordinary ability to process information, learn, and adapt, its capacity varies across individuals and situations, shaped by genetic predisposition, lifestyle choices, and the presence of injury or illness. After sustaining a brain injury, the levels of cognitive function—encompassing memory, attention, problem-solving, emotional regulation, etc.—can fluctuate based on new factors arising from the neurological health changes. Despite these variations, the brain demonstrates remarkable plasticity, enabling it to reorganize and compensate for deficits through targeted interventions, practice, and support. This adaptability underscores the importance of nurturing brain health to optimize its capacity and performance.

Finding no established measure for brain capacity, we developed a practical analogy to help brain injury survivors and caregivers better understand its impact. Imagine brain capacity as a battery that powers how much you can accomplish or how far you can go each day. Following a brain injury, this “battery” is often depleted, leaving little energy to complete essential daily tasks. The overwhelming symptoms frequently drain most of the available power, making even personal, professional, or social responsibilities feel insurmountable. Complicating matters further is the lack of consistency—brain capacity can fluctuate from day to day or even hour to hour, adding an unpredictable layer to an already challenging journey.

Here is an example that will clearly underscore this concept. During one of our therapy sessions, the therapist tried to help us understand the often depleted level of energy. She asked us to imagine that our daily energy consist of 8 units, and by the time we shower and get dressed, we have already consumed two units, that's 25% of your total daily energy before you even start your day.

By understanding this concept, survivors and caregivers can approach recovery with greater awareness and realistic expectations. To understand and navigate brain capacity issue, we present 3 categories of brain capacity:

Impaired –

This category indicates that brain injury patients do not have enough brain capacity to support the required daily activities such as: regular work hours, buying groceries, preparing meals, showering, laundry, cleaning chores, etc. This group of patients needs the most help and support in order to fill in the gap and continue living in a decent manner. Further, not having enough brain power for required tasks also means not enough power for any physical or social activities, so this group is most susceptible to further health issues and social isolation, and help will be needed to maintain their activities and connection to family, friends, and society.

Marginal –

This category indicates that brain injury patients tend to have more brain power and enough capacity to support their required daily activities, including personal and possibly work, but nothing else. So, this group of patients will usually use their entire brain capacity to keep up with required daily tasks, but have no excess brain power to do any physical, family, or social activities. So, while this group has a better outlook than the impaired group, they will need enough help to stay physically active and connected to family, society and other people, in order to stay healthy and prevent social isolation.

Sufficient –

This category of brain injury patients has more than enough brain capacity to complete the required daily tasks and activities. This includes personal, work, family, social, etc. As brain injury patients, our hope is that everyone will eventually make enough progress to reach this category, while continuing to receive help and support. But, interestingly, some patients may reach this category, and if the brain injury symptoms worsen, they move toward the Marginal or even Impaired category. This is not an exact science, and depending on the severity of the brain disruption phase, symptoms, and recovery, they can move back and forth. Again, being in this category does not mean that you don’t need further help and support. The key is, as long as you remain in the brain disruptions phase, or are having brain injury symptoms, it is best to continue seeking help and support.

Note – Every brain injury is unique, and there are varying degrees within each category. Also, depending on the brain disruption level and symptoms, patients may start in one category and improve into a higher category, or temporarily digress into a lower category. That’s what happened to my daughter Sarah. After her fifth Gamma Radiation, she went from sufficient to marginal. Thankfully, that only lasted a couple of years, and now she is back at sufficient for now.