What are your favorite memories of Thanksgiving? Who gathered with you? What foods were served? Do you have any unique family traditions? This year will be different for many of us, perhaps unlike any other. Maybe, the only familiar part of this Thanksgiving will be the memories of past holidays spent together.
Fortunately, in this pandemic-defined year, such memories can be a powerful part of how we cope and maintain hope amidst all the changes.
This week, we return to the What kind of God…? theme and ask: What kind of God would create a world and creatures so dependent on memory?
Since I know next to nothing about the scientific study of memory, I am thankful to be joined by co-author Se Kim. Se currently works in non-profit science administration[i], and before she left the lab bench, her research focused on understanding the role of genetics in learning and memory.
The Neuroscience of Memory
Memory can be defined as the process of recalling what has been learned and retained, or the store of things learned from an experience as evidenced by an outcome (e.g. a changed behavior). There are many different forms of memory, and the type people most commonly recognize is called long-term declarative memory. Declarative memory is how we remember facts and events. This is different than non-declarative types like procedural memory (e.g. how one remembers to ride a bike).
In declarative memory, we “store” the vast input of information gathered from our surroundings as we encounter events and situations. The next time we come across an element of that stored circumstance, we respond with familiarity—that is, our behavior has changed. For example, during this Thanksgiving season, the smell of a fresh pumpkin pie may bring up a funny joke shared alongside a slice of pie last year. The ritual of setting the table may conjure bittersweet memories of those who will not gather this year.
The mechanism of memory formation is complex, with connections to many systems and functions throughout our body. While many circuits of the brain are involved in processing all the different types memory (and recollection), the part of our brain called the hippocampus is integral to the formation of long-term declarative memory.
Learning and memory is studied at the level of neurons. When we encounter and learn something new, neuronal “signals” spark a series of biochemical steps that lead to changes in their cellular structure and synaptic connections. Neuroscientist Donald Hebb famously said, “Neurons that fire together, wire together.” Hebb’s rule refers to how the neurons in the brain undergo changes in synaptic strength when they receive the same (external) stimuli and actively signal (or “fire”) together simultaneously. This adaptability of synapses to strengthen or weaken together is known as synaptic plasticity.
Plasticity in the brain is the basis of one of the biological principles behind learning and memory. As each neuron fires in a certain pattern, they form groups of neurons that “wire” together—providing the expansive number of combinations capable of uniquely encoding specific memories of events and experiences. Multiply this idea with the number of neurons in our brain—about 100 billion!—and we end up with a multitude of signals capable of consolidating and retaining our lifetime of memory.
Our brain provides the physiological matter to store our experiences and knowledge. What we remember from our past, or what we choose to recollect from time to time—both good and bad—can play a significant role in how we live our lives and who we see ourselves to be. And memory is part of what makes us uniquely rational and relational.
- These three videos (3-minute, 6-minute or 10-minute) are all good, and slightly different, introductions to memory.
- Prefer something to read? Try this from Time magazine or articles from Brainfacts.org
- This review is more advanced, but one author, Nobel winner Eric Kandel, literally wrote the textbook on neuroscience and memory.
- A Lutheran pastor reflects on memory.
- Drew looked at neuroplasticity back in September.
Remembering Our Christian Identity
Remembering is a deeply biblical idea. Deuteronomy, Isaiah, the Psalms tell us to remember the works of God. Jesus’s memorable line, “do this in remembrance of me” (Luke 22:19) institutes the Last Supper. And the criminal pleads on the cross, “Remember me when you come into your kingdom” (Luke 23:42).
Memory is also ecclesial. Community enables us to remember what God did for us on the Cross, the teachings and the example of Christ, the promises of Baptism and Eucharist, and the saints that have gone before us. These streams of memory flow deep into the life of the church.
So it is really no leap at all to link Scripture and science to suggest that God desires us to remember and created in us the ability to do so through a perichoretic dance of external stimulus, cellular change, and neuroplasticity. Individually and collectively, God endowed us with the gift of memory. Some would say it is essential to our identity as the people of God.
It will also likely be essential to our experience of Thanksgiving in 2020. I (Drew) will be with my parents. Mom has made great progress since her stroke, but not enough to make that pumpkin pie. This year will be different as I cook with Dad while my wife and daughters celebrate back home. It is memory (and technology) that will bring us together this year.
I (Se) will spend Thanksgiving with my husband and aging parents. I will be creating new memories making the most of the remaining time I have left with my dad here on earth.
Memory might just get us through the entire 2020 holiday season. There will also be grief—a topic we will tackle soon. But our main source of joy this season may come from the memories of good times with loved ones and the traditions of years past.
As a church, even if we cannot meet in person, we will see the Cross and remember the meaning to the holiday season. We will remember why we are thankful and what we wait for during Advent. It is precisely for this reason that God endows us with memory.
Se and Drew
[i] Se is the Director of Membership and Governance at the National Academy of Medicine. She contributed to this newsletter in her personal capacity. The opinions expressed in this article do not reflect the views of the National Academies of Science, Engineering, and Medicine.