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In the midst of everything going on these days, you might have noticed something unusual happening. Maybe you keep walking into a room and forgetting what you were looking for.

Or maybe you forgot the name of the movie you were watching last night. If you feel like you've been more forgetful than normal recently, you're definitely not alone. Forgetfulness is linked to a number of psychological conditions, including stress, anxiety, and depression — three things that are definitely exacerbated by the state of the world.

But if you have been feeling forgetful, just know that, as unsettling as it is in the moment, you can probably expect to feel like your usual self again once life gets a little easier. For the time being, though — or during generally stressful times — some level of forgetfulness is pretty common, and it can affect different aspects of your memory. For instance, if you open a new tab in your internet browser and can't remember what you were trying to search for, that's an issue with short-term memory.

Short-term memories form when proteins in the brain undergo chemical changes that strengthen the connections between certain brain cells, or neurons. Now, brain cells aren't physically connected, but molecules called neurotransmitters do travel from one cell to another, using chemical pathways to transmit signals between cells. And during the formation of memories, those pathways get modified, making it easier for neurotransmitters to travel among specific groups of neurons.

As a result, those groups of neurons are easy to trigger at the same time. When one of them fires, it activates the rest, and that group activation is the memory. But anything you remember beyond about 30 seconds is part of your long-term memory.

Like, if you wore sunglasses yesterday and now you can't find them, that's an issue with long-term memory. Long-term memories form over time. Unlike short-term memories, they involve actual physical changes in the cells of the brain, including the growth of new connections.

A lot of this happens during sleep, when your brain's hippocampus replays recent experiences, which helps neurons make those connections that commit those experiences to memory. Unfortunately, that means that if you're not sleeping enough, that can make it harder for you to remember things one day to the next. But the process of memory formation is also easily influenced by other conditions that the brain is dealing with, and two big factors are anxiety and stress.

Acute stress and anxiety activate molecules called corticotropins, which produce hormones that tell the body to do certain things, like release the stress hormone cortisol. That's useful when there's actually an emergency that your body needs to respond to. But when this goes on for a long time, these molecules can mess with your memory.

That's because corticotropin also changes the shape of dendrites. Those are the branch-like parts of a neuron that extend outward and allow neurotransmitters to pass from one cell to another. So, as a result, there's less transmission between cells.

That makes it hard for neurons to establish the chemical pathways they need to form memories. So if you've been feeling a lot of stress, your brain may be struggling with making memories in the first place. But it may also be struggling with retrieving them, because anxiety just disrupts cognitive function in general.

It puts us in this state of heightened vigilance, where we tend to give more attention to negative distractions even if they're not that important — like an angry stranger on Twitter or an upsetting email. And when your brain's resources are focused on distractions, it's much harder to use those resources to access whatever's stored in your memory. Memory can also take a double-hit in people experiencing depression, which also has become more widespread since the beginning of the pandemic.

Like anxiety, depression messes with memory formation and recall, but in a different way. Whereas anxiety disrupts the exchange of neurotransmitters between cells, scientists believe that depression reduces the number of them — especially the ones that regulate mood, like dopamine and serotonin. And with fewer neurotransmitters going between neurons, once again, it's harder for memories to form.

On top of that, similar to anxiety, depression can get in the way of memory retrieval by distracting the brain with depressive thoughts so it can't focus on tasks at hand, including those that involve memory recall. That distraction can even interfere with what's known as prospective memory, which is your ability to remember to do something in the future, like mail something at the post office or call a friend. If any of this sounds familiar to you, know that, as frustrating as it feels, these are natural responses from your body during hard times.

But just because it's natural doesn't mean that there's nothing you can do about it. Ultimately, if you treat feelings of stress, anxiety, and depression — with things like talk therapy, meditation, good rest, or anything your physician might recommend — you can start getting at what may be the root of the problem, and that may help your memory begin to bounce back. Thanks for watching this episode of SciShow Psych!

SciShow Psych is just one of the shows we produce here at Complexly, and while you're here, I want to tell you about one of our newer projects, called “How to Vote in Every State.” If you live in the U. S., you know voting can get complicated. But no matter what state you live in, we have videos to help you navigate the process.

To check it out, follow the link in the description! [ ♪OUTRO ].