How Does Memory Work? From A Neuroscience Researcher transcript

Memory is the capacity that allows us to learn, connect, and remember experiences and make sense of our lives. [music] In short, it allows us to build our story. Hi, and welcome to Headspace. [music] I'm Dr. Yuande Pierce. I'm a neuroscience researcher who studies the many different functions of the [music] brain. Today, we'll be talking about how memory works and how mindfulness can impact memory. [music] Let's get started.

There are still lots of questions about [music] the neuroscience behind memory. One thing that is known is that the brain structure called the hippocampus plays an important role in learning and memory. In one of the early case [music] studies, a patient known as HM had his hippocampus removed to cure seizures. But by doing so, [music] he was unable to form new memories like remembering if he already ate. [music] This study revealed an anatomical distinction between short and long-term memory and showed that the main function of the hippocampus [music] in memory is memory consolidation.

Memory consolidation is a way for the brain to [music] manage which short-term memories are converted into long-term ones since we don't need to remember everything. [music] Encoding is the first step of memory consolidation and is about transforming [music] sensory inputs from our surrounding environment into something that can be used to create a memory. Think back to the memory of your first crush. You probably still remember their smell, appearance, voice, maybe even touch.

What you probably don't remember [music] is the smell, appearance, or voice of the stranger behind them. That's because the sensory memory only lasts a [music] few seconds. While your brain processes all the sensory information in the cortex momentarily, it selectively transfers the information to the hippocampus where the next step takes place, storage. The hippocampus acts as a short-term storage and organization center for new potential long-term memories.

Short-term or working memory has limited [music] capacity and only lasts a few seconds to hours. For example, [music] when someone asks you to remember a number and you keep repeating it, you can recall it for a short time but soon [music] forget. These short-term memories allow you to use the memory in the moment. [music] If the experience is powerful enough or we repeatedly recall the information within the first few [music] days, the hippocampus will transfer it to the prefrontal cortex for long-term storage where the memory can last hours to months to a [music] lifetime.

It's kind of like that phrase, use it or lose it. The more you repeat something, the more it becomes solidified as [music] long-term memory. To access this information, you need the final stage of memory consolidation, retrieval, or how you get access to the actual memory stores in the brain. The neurobiological mechanisms [music] that underpin memory formation involve the creation of new connections between neurons called sinapses, which allow them to transmit electrical signals between one another by secretreting chemical messengers called neurotransmitters.

The more a signal passes between neurons, the stronger the synaptic connection becomes and the stronger the connection becomes, the faster you can retrieve the memory. The hippocampus is also part of the limbic system which is associated with emotion which makes sense. The hippocampus' synaptic connections to the amygdala, a structure which is associated with emotions, especially fear, means that they can work together to associate emotions to new memories.

When it comes to mindfulness memory, mindfulness is a skill that needs to be learned. So, you can expect the hippocampus to be involved. But can mindfulness actually improve memory? There's not enough conclusive research on the direct impact of meditation on memory? [music] But numerous studies provide clues. Studies on long-term meditation in elderly [music] populations, so those vulnerable to age related cognitive decline and Alzheimer's disease, suggest that there is less age related gray [music] matter atrophy in long-term meditation practitioners.

Another study found that a few weeks of meditation training helped reduce mind wandering and improve attentional focus during the verbal reasoning section of the GRE. This study concluded that these findings support mindfulness as [music] a way of promoting attention to the present moment and minimizing interference from past [music] events. Additionally, another study actually looked at the neurobiology of a group of people who meditated to those who did not.

They monitored physical changes within the brain through what's [music] called fMRI, which is a way to indirectly look at brain activity through blood [music] oxygenation. What researchers found was that those who meditated [music] showed less neural activity in their vententral posterior medial cortex or the region of the brain that is associated with [music] mind wandering. I'm Dr. Pierce and thank you very much for watching.