Managing memory problems after brain injury

I'm going to be talking to you about managing memory problems following acquired brain injury.

I'm going to start today's presentation with a brief introduction of what we might think of as memory. This is from a neuropsychology point of view, discussing different theories of memory, but very much relating that to how we might understand memory in everyday life, particularly as this is what is important to rehabilitate and address after acquired brain injury. We will be focusing on why memory changes after acquired brain injury, the assessment of memory function, and flagging up secondary influences on memory function. This is in a more positive, less medico-legal approach, looking at how we can create the best environment for someone's memory to function in day-to-day life. Of course, I'll then be talking about different ways of rehabilitation after acquired brain injury and, finally, a brief note on brain training.

What is memory? Clinically, a lot of the time, people will come along after seeing a neuropsychologist after an acquired brain injury, and they'll be talking about short-term memory problems. Memory from a neuropsychology point of view is slightly different. We can think of short-term and long-term memory, but from a neuropsychology perspective and understanding of theory, short-term memory is indeed very short; it's that initial capture of information—what you might hear or see. It then gets put into a working memory store: what do we need to do with that information? Do you need to respond to it straight away, or put it into longer-term storage? When someone says, "I'm having short-term memory problems, I can't remember what someone told me yesterday," from a neuropsychologist's perspective, I'm thinking more in terms of long-term memory. But it's those everyday memory problems that people are experiencing that are important because that will act as the driver for rehabilitation.

A neuropsychological assessment looks to see where things are breaking down: is there a problem with registration (that short-term memory difficulty)? Is it a problem of actually putting it into a permanent store? Or is it a problem of having it in the storage system, but not being able to get it out when you need it? From a theoretical point of view, we can also think of other types of memory. There is episodic memory—memory for experiences, episodes, and things that you've done. This is in contrast to semantic memory, which is our memory for facts and knowledge that we've acquired over our lifetime. I also wanted to mention prospective memory, which is remembering to do something at a future time. This is a really important facet of memory that underpins everyday functioning; we need to remember to go to the doctor's appointment, pay our bills, or pick up our kids from school. These are all aspects of memory that can be affected after acquired brain injury.

The pattern of memory impairment will differ according to the mechanism of injury, whether that be a traumatic brain injury following a motor vehicle accident, sports, falls, stroke, or encephalitis. If we think of a traumatic brain injury and the high-speed impact from a motor vehicle accident, because of the shear forces involved and the acceleration-deceleration forces, typically the parts of the brain involved are the temporal lobes—the seat of memory functions—and also the frontal lobes, as well as the communication between those systems. There can also be secondary, non-brain injury factors that make it difficult for someone to remember things, such as poor sleep, fatigue, effects of medication, pain, and mood or anxiety symptoms. While a neuropsychologist will take these into account, these may be moving parts that can also be addressed to support everyday memory function.

Memory changes are common after acquired brain injury and can have a significant negative effect on everyday functioning. This could be activities of daily living, such as grocery shopping, paying bills, or turning the stove off. Memory problems can act as significant barriers to a successful return to work or returning to learning. Memory impairments can also have a significant effect on relationships and how a person sees themselves or their sense of self, such as breaks in the narrative of who you actually are if you can't engage in friendships or work as you previously did.

Fortunately, there is a strong evidence base for the rehabilitation of memory problems after brain injury, but it's very much adopting a compensatory as opposed to a restorative approach. We are not trying to restore that impaired function to "cure" the memory problem; it's about identifying the problem and working around it to reach an everyday memory goal. Memory is not a muscle, so repetitive encoding is not going to make memory stronger and improve functioning. It is about compensating and working around the problem.

Memory rehabilitation needs to be goal-directed, with collaborative goals established with the individual. It could be specialized rehabilitation within a brain injury unit, community-based rehabilitation, or one-on-one therapy. I need to emphasize that we need to train the use of compensatory strategies and memory aids. We can't just tell someone to use a diary or rely on their phone; it needs to be specialized training. Once a memory aid is matched to the individual and their goals, training involves learning how to use that skill, applying it, and ideally fostering the generalization of that skill to other memory tasks.

There are many different memory aids, broadly categorized into low-tech and high-tech aids. Low-tech aids include paper-based diaries, notice boards, Post-it notes, calendars, medication boxes with alarms, and voice-prompted door reminders. Technological aids are now ubiquitous, including smartphones, iPads, and digital assistants. There is growing evidence that these are superior to paper-based prospective reminders because they are not passive; they can set alarms or vibration alerts to attract attention and provide content-full queuing, such as telling you exactly what you need to do, like "call the doctor" or "take medication." However, it's important to keep it simple and tailor the technology to the individual's comfort and specific needs.

I do not advocate the use of brain training for the rehabilitation of memory problems, as there is very limited evidence that any improvement on brain training games will generalize to day-to-day life. Memory is not a muscle; repeated use of these games will not transfer to university courses or work meetings. That said, if you enjoy them, they might improve your mood, which can help support memory function. Similarly, while mnemonics can be used for things like learning names and faces, they are often too effortful for day-to-day memory management.

In conclusion, memory changes are common after acquired brain injury, but there is a good evidence base for compensatory memory rehabilitation. Rehabilitation needs to include training, be goal-directed, and developed collaboratively. If you are experiencing memory problems after an acquired brain injury, I recommend referral to a clinical neuropsychologist or a good neuro-occupational therapist to adopt a holistic approach and optimize everyday function.