Have you ever tried to remind your friends of a memory you shared, only for them to tell you they don’t know what you’re talking about? Or even shared an anecdote before remembering that, actually, you dreamt that?
You could be experiencing false memories. A study found that sleep deprivation can lead us to experience false memories that often feel vivid even on reflection.
According to Simply Psychology, false memory is a psychological phenomenon whereby an individual recalls an event that never happened, or an actual occurrence substantially differently from the way it transpired.
While this is often harmless and, at most, a bit embarrassing, it can lead to much more concerning scenarios. Simply Psychology warns: “Instances of this phenomenon may range from the mundane—such as remembering that you ate breakfast when you actually did not, to the serious—such as falsely recalling that your boss assaulted you.”
So, what does this have to do with sleep and how do we fix it?
The connection between poor sleep and false memories
To shed some light on how this happens and what you can do, if anything, to combat it, Martin Seeley at MattressNextDay discussed how and why sleep deprivation can cause you to have false memories.
Interrupted REM sleep
Seeley explained that Rapid Eye Movement sleep (REM) is when dreams are most vivid, and when the brain is most active. During this time, the brain processes and stores memories from the day.
However, if you are experiencing sleep deprivation, this function doesn’t have the opportunity to occur. This means that memories are less likely to be remembered, and information isn’t absorbed.
If you often have a glass of wine before bed, it may seem like a good way to wind down and help you relax but Seeley warns that it has the opposite effect. While alcohol can make you feel drowsy, it disrupts your REM cycle and therefore impacts memory consolidation.
Seeley said: “Sleep consists of four stages; wake, light sleep, deep sleep, and REM, repeated four or five times. Alcohol is a nervous system suppressant, which is why you feel more relaxed when drinking, but drinking before bed means that your REM cycle can be suppressed.”
Because alcohol is a sedative, it makes you fall into deep sleep more quickly, and the cycle is imbalanced, leading to sleep disruptions.
Impaired hippocampal function
The hippocampus is involved in the process of learning and forming memories, making it essential for long-term memory retrieval. Studies have found that alcohol impairs hippocampal function, which is why drinking can lead to ‘blacking out’ and memories formed while drunk can be more prone to error.
When we sleep, the hippocampus strengthens neural connections by replaying experiences like a film. Your brain then identifies the important details, refining the memory by weeding out irrelevant information.
Impaired prefrontal cortex
Additionally, the prefrontal cortex also plays a part in memory recall. The bulk of the memory is stored in the hippocampus, but individual and more specific details are stored in the prefrontal cortex.
When sleep deprived, the amygdala, the fear centre of the brain, goes into overdrive and shuts down the prefrontal cortex, blurring the lines between which memories are and are not real.
Can false memories be corrected?
False memories aren’t necessarily permanent, though some are stronger than others. The length of time since the event is important, as older memories are harder to correct, and frequently recounting, repeating, and reinforcing a memory solidifies it in your mind, so a false memory you often look back on can be difficult to recover.
Seeley assures that false memories aren’t necessarily permanent, though some are stronger than others. The length of time since the event occurred is important as older memories tend to be harder to correct, and frequently recounting, repeating, and reinforcing a memory solidifies it in your mind.
Cross check your false memories with people who were there, photos, videos, written accounts - anything you can find that might jog the correct memories.
Seeley added: “It’s important to remember that not all memories that differ from other people’s versions of events are automatically false, and in need of correcting. Different perspectives, emotional attachments, and interpretations of events can lead to having a different memory to someone else.”
How can you protect your memories?
Seeley recommends aiming for at least 7-8 hours of sleep each night. Set a consistent sleep schedule and stick to it even on weekends, to help regulate your circadian rhythm.
He added that meditation has been proven to improve memory and cognitive function.
Finally, exercise can benefit both sleep and memory performance. Regular exercise can help you to fall asleep faster and sleep more deeply, promoting brain cell growth and strengthened neural connections. This increased neuroplasticity helps you to learn new things, ultimately improving memory function.