Finding Your Way Back by Remembering How You Got There

The brain is a complex place to live. It remains a bit mysterious exactly how memories are encoded and how widely this information is distributed in the brain. What is well understood, though, is that memories include information that goes well beyond just what is remembered. This includes when and where the memory was encoded.

Keep your eye on the same game

Over my many years of martial arts training, I've learned and taught many patterns of movement in different places, with different people, and in different traditions. One constant is that to succeed in transmitting the information in these movement patterns, the orientation for learning must be consistent.

Specifically this means making sure that the orientation between the teacher and trainees and where they are facing is the same during the learning. This means maintaining the external environment during memory encoding. This is important because if you are learning a martial arts sequence, it's not just the order and type of punches, kicks, blocks, and throws that your brain is encoding as memory. You are also encoding where you are relative to others, what direction you are facing, and other features of the environment. Those become part of the learning and memory experience.

Keeping a grid in place

We have neurons in our brains, especially in the hippocampus and surrounding regions, that encode so much about our memories. These "place" and "grid" neurons indirectly include information about where we were when the memories were formed. What was around us, what we were doing, probably who was there as well.

Almost certainly, these networks are one of the reasons why when you've forgotten where you put something, going back into the same room and retracing all your steps can help with memory retrieval.

Application in Alzheimer's disease

These features certainly apply to all kinds of behaviors. Although I noticed this in teaching and training of martial arts over the years, and also when it was done poorly, such as rotating or altering the orientation of people and place, it turns out this has implications for things where memory is heavily challenged, such as Alzheimer's and dementia. It also makes me wonder if moving such folks out of their homes, where they feel secure and have memory cues all around them, and into new clinical environments is really the greatest idea.

Azul Silva and María Cecilia Martínez from Argentina summarized knowledge about this and applications to clinical memory dysfunction in their nice review. These researchers suggest that when we move around, "we build a cognitive map: an internal representation of the territory... [where] place cells and grid cells... form a neural network whose activity is critical for the representation of self-position and orientation along with spatial memory retrieval." Observations also support encoding of "multiple aspects of an experience besides the position in space, suggesting that they have a crucial role not only in spatial navigation but also in episodic memories."

While there is a typical decline in spatial memory as we get older, Silva and Martinez further suggest that "this is dramatically increased in pathological conditions such as Alzheimer’s disease." Importantly, the neuronal populations predominately affected in Alzheimer's are found in similar hippocampal regions in which we find place and grid neurons. This is seen clinically in the common "disorientation and wandering behavior" and may be something amenable to enhanced rehabilitation using virtual reality.

While we wait for important clinical application, we should be mindful to keep the environment and orientation of the people in it as consistent as possible in the early stages when we are doing our own teaching, learning, and training. Now that we know more of the science behind it, we shouldn't feel too odd retracing our steps to find items we've lost, misplaced, or forgotten about around the home.

(c) E. Paul Zehr (2024)