Art of memory
Once again, this week the basics and topics class share a topic, Memory. The basics lesson is very complete, describing memory systems, how memories are formed and stored, the brain physiology behind memory, and memory loss. Make sure to read it prior to this lesson. (Click here to view the online Basics lesson on memory). And look for the Jeopardy game this week, which will provide a fun way to show what you learned. We will play in class, and on Zoom. After, we will upload to the lesson page so you can play alone or with your family and friends.
This week, our topics class will look at the Art of Memory, and some factors which can affect our memories. Included in this week’s lesson is some information on sleep, on reconstructing memories and on the impact of aging.
Memory and sleep: Consolidation
As we learned in the basics lesson, memory requires three processes: encoding, consolidation and retrieval. Sleep is critical in the consolidation phase of long-term memories. There is a two-stage memory mechanism with a fast store and a slow learning store.
The fast store encodes the memories (hippocampus), which allows for quick and efficient encoding. However, they are unstable and vulnerable to inference. Over time, this information is gradually integrated into the slow learning store for long term storage (neocortex).
Sleep allows reactivation of new memories, allowing them to be strengthened and adapted into long-term storage. (Rasch, 2013) REM is important to stabilize transformed memories. Memories are stabilized in the hippocampus, and then redistributed to temporary storage throughout the brain. This suggests that long term memories can be formed in different physiological systems.
Research on sleep
Research has looked at how sleep affects learning in the brain. Here are some of them: (Rasch, 2013)
· Sleep helps to passively protect memory from interference. The best time to sleep is shortly after learning.
· Some studies look at the value of sleep in forgetting “parasitic modes” of activity, which are essentially those weird dreams that you sometimes have. These can be dreams of fantasy, obsession, and hallucination like responses. REM sleep may involve a reverse learning mechanism which reduces the probability of remembering these dreams, and enhances the efficiency and storage capacity of the memory network. (Do you really need to remember those dreams anyway?)
· The “sleep to forget sleep to remember” (SFSR) hypothesis, assumes that REM sleep after a bad emotional experience strengthens the content of the memory but reduces the emotional response when the memory is reactivated. This would continue to work on subsequent nights with REM sleep.
· Another theory assumes that different sleep stages consolidate different types of memory. For example, declarative memory profits from SWS (slow wave sleep), while nondeclarative memory is supported by REM sleep.
· Sleep does change with aging. Older adults sleep less and awaken more frequently during the night. This is due to a gradual decrease in SWS, especially over the prefrontal cortex. The time in REM sleep remains relatively unchanged, although it does decrease in the elderly.
Below, watch a five minute video which describes the importance of sleep and memory consolidation.
Reconstructing the memory
Memory can be crucial for so many life experiences. Often it is one person’s recollection which can affect the lives of so many others. How accurate are these memories anyway? Unfortunately, they are largely inaccurate, skewed, or are false memories.
Recall or retrieval is the re-accessing of events which are already encoded and stored in the brain.
During recall, the brain replays the pattern of neuron activity generated at this particular event. Memories can be incorporated with new information and suggestions.
Memory retrieval is automatic. If distracted, it may slow but will still retrieve memory.
Confabulation is the spontaneous production of false memories which have not occurred or are of actual events but inaccurately placed in space or time. They can be mundane (what they ate for breakfast) but can also be bizarre (visiting an alien spaceship). In most cases, the person is not aware of this deficit in their memory. The cause is usually a type of brain disorder.
More on confabulation: A 19th century Russian neuropsychiatrist named Sergei Korsakov noted confabulation in his alcoholic patients and attributed it to an effort to reduce gaps in their episodic memory with semantic memory to make sense out of the event. An alcoholic who is having difficulty remembering things that have happened earlier (episodic memory), can replace them with random information that fits in (semantic). This is a type of confabulation which is common in alcoholic dementia.
English professor Frederick Bartlett, researched how people share stories (with errors, modifications and even different endings) and concluded that we do not retrieve memories but reconstruct them instead. We piece together little bits of things that we know along with things we have recently stored. When there are gaps, we insert semantic memory. This would be a different type of confabulation.
Studies on reconstructing memories (Shimamura, 2013) (Hayasaki, 2013)
Some examples of studies on reconstructing memory:
· Jurors were very likely to convict a person based solely on eyewitness accounts, even when the witness was described as having extremely poor eyesight.
· Following a store robbery, when faced with a line up, employees were not always correct (42% correct, 22% couldn’t recall, and 36% chose the wrong person).
· Different descriptive words when describing two cars included hit, bumped, collided and smashed. The speed estimates from witnesses rose in accordance to the word used. In addition, different descriptive words on impact resulted in different memories, with those who had heard the term smashed were more likely to falsely remember glass breaking. (McLeod, 2014)
Professor Elizabeth Loftus has spent decades researching how memories can be planted in someone’s mind if they are exposed to misinformation, or asked suggestive questions. Her most famous work was the lost in the shopping mall study, where a group of participants falsely remembered being lost in a shopping mall as a child.
Separate from normal people are those with “highly superior autobiographical memory”. These handful of individuals can remember details of what happened every day at every time since childhood. They are correct 97% of the time. However, when tested with normal people on memories which were false, the number of people believing the false story to be true is fairly close, whether you are a superior memory person or a normal person.
The work of Professor Loftus and others who study reconstructing memories has led to caution for journalists, lawyers, police officers and more. A true story is filtered through the teller’s take. Our mind and memory do not only record and retrieve, but they also infer, fill in gaps and construct. The validity of these memories may not be exactly how they happened, but they would be the way that we chose to remember.
Video:
This short segment of a psychology class describes one of the more well-known studies of Professor Elizabeth Loftus. It also analyzes the study for relevancy.
Video:
How are false memories implanted? Fascinating! How would you do if you were in this situation? Could you implant a false memory with these tools???
Video:
This is an absolutely fascinating Ted Talk. We have shown this before. It is a must see for a look on the damage that faulty memory can cause.
Aging, memory and cognition
(Brickman, 2009)
As a quick review, there are two types of memory. There is short term memory and long-term memory. Short term memory includes sensory (which is a brief glimpse of something you just encountered) and working memory (which keeps the memory in your head for a very short time). There are three types of long-term memory. They are episodic (remembering an episode on your life), semantic (a fact that you learned long ago, like the capitol of Indiana) and procedural (a skill you have learned).
As we all know, memory does fade for many people as they age. However, not all of the types of memory decline. In fact, procedural and semantic memory show little decline with aging. Problems with procedural memory may be related to physical things like arthritis and vision problems, and mostly people remember those things they learned when they were young (semantic). The type of memory affected by aging is episodic memory.
Even with episodic memories, there can be a difference in which ones are affected by aging. A long-time episodic memory may be etched in your brain (one of your family’s dark secrets perhaps). This memory may even have some semantic memory mixed in. This memory is probably safe with age.
But newer episodic memories may be harder to retrieve. They may have been encoded, but without constant rehearsal, they can begin to fail.
Researchers have been interested in the memory decline with age theory for years, and have done many studies with older adults and students on campus. However, it wasn’t until the 1990s when researcher Lynn Hasher began to look at the time of day for these memory studies. She found that most of these tests take place in the later afternoon, for the convenience of students who are in class most mornings. However, the adolescent brain is most active during this time, unlike the brains of older adults. So, she tried switching the schedule and trying both early and later to see if circadian rhythms had an effect on memory. As it turns out, it did. She found that when time is controlled between the younger and older subjects, the difference dropped dramatically. In fact, the time of day had an effect on memory of all ages.
The research of Lynn Hasher caused her to come up with a different way to define cognitive decline. She prefers cognitive transition. The way that we interact with the world changes as we age. We lose the ability to multitask. We spend less time on details and think instead of the big picture. (Spending less time on details may explain why episodic memories decline with aging). As we age, we also become more creative. All positive ways to consider aging and memory!
Improving your memory
(How to improve your episodic memory, 2020) (Sazma, 2019) (Brown, 2016) (Banducci, 2017)
We have learned that it is episodic memory (and the more recent version) that transitions as we age (I do prefer that to decline). One reason why our episodic memory fades is because our frontal lobe function also declines with age. As a result, new information needs to be repeated to get it stored.
Episodic memories are not in a vacuum. They combine past experiences and vital information so that the retrieved memory is robust. But, with the weaker frontal lobe, there is difficulty retrieving these past experiences. There are strategies which can improve the way that episodic memories work. They include:
· Focus your attention. Use mindful awareness when in a new situation and pay attention. Focus on the information when you first hear it.
· Cue: If you are having difficulty remembering someone’s name, think about other things you know about them. Or, try going through the alphabet to find their names. These are ways to use what information you have to complete that memory.
· Use your brain: When you learn something you want to remember, make a mental link to it. Focus on a keyword or phrase, or a picture which would go with the context. Associating something else with the thing you want to remember would help build the memory, and improve your episodic memory.
· Practice mindfulness: A 2016 study found that even a very brief mindfulness training can improve free-recall memory performance, and that mindful attention can impact motivation and episodic memory.
· Active experiencing (AE) combines mindfulness training with immersive acting, and has had promising results in older adults with limited formal education.
Here is a nice image to help illustrate ways to a better memory...
Summary
This lesson provided a look at three things that affect your memory: sleep, reconstructing memories, and aging. And in each example, you have learned some ways to use this information to improve your memory. So, get a good night’s sleep, be wary of some of the more obscure memories that you have, and use strategies such as focusing your attention, mindfulness, exercise, challenge, diet and more to maintain a healthy memory!
Final parting image on memory
Works Cited
Banducci, S. E. (2017, May 9). Active Experiencing Training Improves Episodic Memory Recall in Older Adults. Retrieved from frontiersin.org: https://www.frontiersin.org/articles/10.3389/fnagi.2017.00133/full
Brickman, A. A. (2009). Aging and Memory in Humans. New York: Elsevier, Ltd.
Brown, K. e. (2016, April 26). Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation. Retrieved from journals.plos.org: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0153309
Hayasaki, E. (2013, November 18). How Many of Your Memories Are Fake? Retrieved from theatlantic.com: https://www.theatlantic.com/health/archive/2013/11/how-many-of-your-memories-are-fake/281558/
How to improve your episodic memory. (2020, January). Retrieved from health.harvard.edu: https://www.health.harvard.edu/mind-and-mood/how-to-improve-your-episodic-memory
Joordens, S. P. (2011). Memory and the Human Lifespan. Chantilly, VA: The Teaching Company.
McLeod, S. (2014, Jan 11). Loftus and Palmer. Retrieved from simplypsychology.org: https://www.simplypsychology.org/loftus-palmer.html
Rasch, B. a. (2013, April 2). About Sleep's Role in Memory. Physiological Reviews, pp. 681-766. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3768102/
Sazma, M. (2019, February). Using acute stress to improve episodic memory: The critical role of contextual binding. Retrieved from sciencedirect.com: https://www.sciencedirect.com/science/article/pii/S1074742719300024
Shimamura, A. P. (2013, September 4). Reconstructing Memories with the Stories We Tell. Retrieved from psychologytoday.com: https://www.psychologytoday.com/us/blog/in-the-brain-the-beholder/201309/reconstructing-memories-the-stories-we-tell