While you were sleeping...
- Kathy Gallagher
- 21 hours ago
- 8 min read
Updated: 1 minute ago
Sleep might just be the secret sauce you're missing. Here's a primer on what sleep can do for both your memory and your mood.
I awoke this morning at 4:55 a.m., five minutes short of my 8-hour goal, feeling smug.
Occasionally when I’m particularly proud of myself, I secretly (well, I guess it’s not a secret any more) give myself a high five. This I did today, a small celebration of sleep victory.
Sleep has been a huge battle for me, and it has become my focus since meeting with my new Neurologist last month.
It took nearly three years to get that appointment. I was curious about a new infusion therapy, Lecanamab, that held promise for stopping the growth of amyloid plaques in the brain--the plaques that often result in Alzheimers. After jumping through several hoops, I at last had proof of “moderate to frequent” amyloid in my own brain. This was my golden ticket to get an appointment at OHSU’s dementia care clinic, and after another 7-month wait, I was both nervous and excited to meet the Neurologist.
But after a great conversation and a series of tests, he did not recommend the therapy I was hoping for, at least not for this early stage of mild cognitive impairment.
“There are some risks to this therapy,” he said, “and since you don’t yet have Alzheimers, I’d like you to try some other therapies first. Let’s begin by addressing your sleep.”
Wait, what?
Part of me was disappointed, as I had great hopes for this treatment. But another part of me was open and curious. Sleep and I had not been on good terms, and I was relieved to begin addressing the cascading consequences of poor sleep.
Sleep, I’m learning as I research, has everything to do with both mood and memory.
Trauma is weird. In 2024 when my husband Jim’s life and limb hung in the balance, my brain went into flight or fight mode, frantically whirring, trying to solve everything at once, and sampling all the future scenarios that might come our way.[1]
My bed became a haven, the place where I could stop rushing at the end of the day, be alone, and cry or think or worry.
Some nights I lay awake trying to solve everything or remember what was important. Other nights I just fell exhausted into oblivion, my dreams fractured and bizarre as my brain continued trying to Solve Everything as I slept. Occasionally I awoke rested and renewed when morning dawned, but more often the weight of the world urged me out of bed, my amygdala fired up and predicting doom. Sometimes I was so exhausted and foggy I strained to even remember what had happened the day before.
That’s when my sleep issues began, if my memory serves me correctly. (That's a phrase you’re likely to hear a lot from me in the future!)
I knew that eight to nine hours of sleep was critically important for brain health and recovery, but the harder I worked at it, the worse my sleep became. Somewhere, often around 4:00 a.m. but occasionally much earlier, my mind would begin spinning wildly, alert and curious.
I battled to get back to sleep, putting on music or listening to something boring, but my busy brain would just frantically chatter louder than the sounds, and soon I’d be jotting down thoughts that seemed genius or researching questions that really should have waited until after daylight. Occasionally I would fall back asleep at a time when I ought to be rising, thus confusing my body clock further. I lived my days in a kind of frantic fog.
Sleep, I’m finding as I research, has everything to do with both mood and memory.
While you’re asleep, your brain is not.
While you’re asleep, your brain is not. It’s actually hard at work consolidating new memories, linking different pieces of information together, associating them and filing them, like a little night shift librarian. Your brain also does repairs to itself while you sleep, even helping to remove some of those amyloid plaques! It takes out the trash, and clears our brain to better absorb new information the following day.
Our sleep cycles explain why so many different things can be happening during different phases of sleep, and how they UN-happen when sleep is missing. Our brain waves change with each new phase.
Here’s a summary of what your brain is doing while you are sleeping:
Lightest sleep:
The first phase, lightest sleep (also called N1), lasts just 1 to 7 minutes. In this stage alpha brain waves shift into theta waves. Your body temperature drops, your breathing and brain activity slows, and your muscles relax, dropping you from tired, to drowsy, to asleep.
This phase happens only once in the night, but the other three phases repeat, in this order, up to six times a night:
Light sleep:
In this phase (N2), your breathing and brain activity slows further and your brain blocks out noise. Light sleep is associated with learning and memory. It’s kind of a housekeeping stage, where your brain rids itself of unnecessary information and files new information away.[2]
The light sleep phase is around 20 minutes long, but grows slightly longer with each cycle throughout the night. About half of your sleep will be light sleep.
Deep sleep:
N2 is consistently followed by N3, the deep sleep phase when you are harder to wake. In this phase your brain takes on a pattern known as delta waves. Restorative sleep happens in this phase, and in it your muscles grow and your body recovers and heals as your immune system kicks in.
The slow waves of deep sleep are required for your brain to take the new information temporarily stored in your hippocampus and move it to your cerebral cortex. Deep sleep, therefore, helps convert short term memories into long term ones. This stage is also critical for feeling refreshed.
Deep sleep is initially a long phase, but grows shorter with each cycle as the night progresses.
REM sleep.
The last stage in each cycle is the rapid eye movement phase, or REM sleep (N4). This is the dreaming phase, when your brain activity level picks up, approaching the brain activity level of your waking hours, so it is naturally less restful. Here your brain replays experiences and associates different pieces of information together, strengthening neural connections and contributing to insightful thinking and creativity. It also serves to integrate emotions and complex memories.
This stage of lighter sleep is short in the earliest sleep cycles (thankfully, so you can rest), but it increases in length with each cycle, preparing your brain to begin processing what you may need for the coming day, inspiring energy and problem-solving and motivation, and moving you toward wakefulness and alertness.
Which brings us to that annoying 4:00 a.m. wake-up call.
It is likely those of us who find ourselves wide awake at 4:00 a.m. are waking during the long REM sleep phase in the last sleep cycle or two. This is when I find a million ideas beckoning as my brain links different pieces of information together, asking myself questions that feel genius, and feeling a surge of motivation to just start hunting for answers Right Now!
Adding additional weight to this urgency is a cortisol surge that naturally happens around 3:45 a.m. or so. Cortisol is strategically designed to raise our energy and motivation levels as dawn approaches, motivating us to seize the day. But as we age, this hormonal surge can seize our sleep instead, particularly as the lighter, REM phase lengthens around this time.
So what can we do about it?
I’m experimenting with several small changes, and finding some positive changes:
I restrict my bed hours to a specific 8-hour window. This is helping me sleep more soundly, but even when I don't, I get up at my scheduled rising time anyway. If that makes me more tired in day, it rewards me with a good sleep the following night, and I'm back on track.
A small dose of a sleeping aid prescribed by my doctor makes falling asleep a dream (pardon the pun). It also contains a small amount of serotonin, which may account for quieting those night-time surges of anxiety, adrenaline, or disturbing dreams that interrupt my sleep.
I’m creating a favorites list of calming sleep music or meditations to listen to when I do awake with a busy mind. Audio recordings of Scripture are helpful, too, to silence my thoughts and help me return to sleep.
I’ve returned to intermittent fasting, which is said to also help you sleep more deeply. And as a bonus, it can also nibble away at those annoying amyloid plaques!
I've switched to half-caff coffee, and avoid caffeine after 10:00 a.m. Caffeine has a half-life of 5-7 hours and a quarter-life of 10-12 hours, and getting it out of your system before bedtime is critical, though I occasionally use it treat a migraine.
Meditation has been a part of my life for a few years now, and I’m grateful to have this tool for calming a racing mind and reducing anxiety. This is true both for night-time wake-ups, and during the day when I find my stress level rising or my ADHD mind racing.
I’m being kinder to myself. It’s easy to value ourselves by our productivity, but if the stress of cramming a lot into each day raises my alertness and anxiety, it’s not a good trade. In lieu of a nap, which could throw off my nighttime sleep, I’ve given myself permission to take a break mid-day. I also occasionally take a “day off” if life has been extra busy, in order to calm my nervous system.
These changes have helped me inch toward eight hours of sleep most nights, with only brief waking moments--minutes instead of hours. My bizarre, crazy dreams have faded, and I no longer awake in a panic. During the day I am reaping the benefits of clearer thinking and calmer emotions, though I still struggle to consolidate new memories permanently.
Tiny beginnings can bring big changes.
I’m still me, even with mild cognitive impairment.
I still delight in this world, exhilarated as I watch new leaves unfurl or smell the earth while I tease up weeds whose roots are still loose in the damp, spring soil. I am madly snapping pictures of skies, hoping to learn to paint them. In a few minutes I’m heading out the door to take a hike and have coffee (decaf) with a friend.
There is cause for concern, but also so many reasons to hope. Like the newly unfolding leaves of Spring, tiny beginnings can bring big changes.
Sleep is my Step One.
. . . . . . ABOUT THIS BLOG . . . . . .
PURPOSE #1: It’s for you. My hope with my Growing, OLD posts is to share helpful information I’m learning to give hope, understanding, camaraderie and courage to those with concerns about aging or cognitive impairment for themself or loved one. Feel free to share a link with someone interested in this topic.
PURPOSE #2: It’s for me. In my stage of mild cognitive impairment, I’m having difficulty consolidating new memories. My comprehension is great, but when I reach back for that cool thing I just learned, my brain has not always consolidated those ideas or moved them to the cerebral cortex where I can later retrieve them. So part of my sneaky plan in parking this information here is so that I can find it again!
DISCLAIMER: While I try to pass on good information, I am not a medical professional, so please also do your own research, and talk to your doctor for professional help with memory or sleep issues. A few resources about memory and sleep are linked in the footnote below.[3]
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[1] See my “One step at a time” posts if you’re not familiar with the story of Jim’s battle with sepsis and his subsequent amputation and return home.
[2] See Every Stage of Sleep Explained in 4 Minutes, by Bing Videos
[3] Here are some additional articles on the topic of sleep and memory:
Three TED Talk videos I found helpful:
And a quick video about sleep cycles: