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In our complex world, we are constantly bombarded with information from our environment. How do our brains decide which information is important for us and which information can be ignored? Turns out there is a gatekeeper mechanism that helps with this process.
When you go grocery shopping, it is likely that you are making your way through the grocery store ticking items off a (mental or physical) shopping list. Entering the store, you check your list and remind yourself to grab apples and bread. Most stores have the produce in the front, so you should first remember the apples while keeping the bread in mind to use later. How does our brain take care of this process of letting important information in and keeping it active until it is ready to be used?
Working memory – your brain’s workspace
After checking the shopping list, both the apple and the bread have entered your working memory, the mental workspace responsible for temporarily holding and manipulating information. Research shows that this workspace is limited, though the exact limit depends on how this is studied. Therefore, our brains need to have a mechanism filtering which information to store in working memory. This process is called working memory gating.
Gates in and out of your working memory
When checking your shopping list, only information that is relevant right now (so apples and bread) makes it into your working memory while other information (like the medication that is also on the list for you to get at the pharmacy later) is not let in at this moment. Selectively “opening the gate” to let in information is called working memory input gating.
Then, while you keep multiple things active in your mind, there also needs to be mechanisms that only let the relevant information out, like the apple in the produce section but not information that needs to be remembered for a later point. This is working memory output gating, like opening a gate to let the information that is important at this moment guide your behavior.
The basal ganglia as a gatekeeper of your brain
The basal ganglia, a collection of nuclei* deep within the brain (see image), play a pivotal role in working memory gating by collaborating with the prefrontal cortex. While the prefrontal cortex acts as a central hub for cognitive control, the basal ganglia regulate the selection and inhibition of information entering and exiting working memory. Studies suggest that the basal ganglia, particularly the striatum, is connected to the prefrontal cortex, integrating information to facilitate decision-making and action selection. This interaction is crucial for filtering relevant information and suppressing irrelevant distractions. Dysfunction in this circuitry of basal ganglia and prefrontal cortex can lead to difficulties in attention, decision-making, and cognitive flexibility.
Image description. The human basal ganglia, a structure important for movements, learning, emotion, and cognition. The differently colored structures are the different nuclei of the basal ganglia. Image via beyondthedish
In conclusion, the concept of working memory gating reveals the intricate neural mechanisms that govern how our brains deal with all of the information in our environment without being overwhelmed. Understanding these mechanisms and how they link to the rest of our memory system not only deepens our understanding of the brain but also holds promise in addressing cognitive disorders that are associated with working memory deficits.
*A nucleus (plural nuclei) is a cluster of neurons in the central nervous system
Author: Helena Olraun
Buddy: Viola Hollestein
Editor: Vivek Sharma
Translation: Lucas Geelen
Editor translation: Maartje Koot