The Richest Palace is in Your Brain

Siddhant Dharap -

The World of Memory

Imagine you are given 60 seconds to memorize 52 cards, with only one chance to look at the deck and no room for errors. That may seem like a lot to memorize in a short amount of time—a feeling shared by students preparing for a major test or important interview—but such a feat is possible. Your brain can generate a tool meant for tasks like these, limited only by your imagination: the memory palace. Known as the Method of Loci (MOL), the memory palace is a mental blueprint conjured by your mind that depends heavily on a combination of visual and spatial stimuli. The manner in which you can memorize information with the MOL incorporates versatility in the mental blueprint due to the brain’s ability to process more visual information than auditory, meaning that the amassed visual information can associate and activate memories better than just words [1]. The MOL’s reliance on spatial relationships between familiar locations allows the user to effectively arrange and recollect information in a manner outshining your typical mnemonic [2].

The MOL draws upon a combination of mental navigation and spatial routes to powerfully boost memory [3]. By creating a pathway to connect objects within the palace, the MOL enhances memorization capabilities, which may be magnified by cues such as emotions or familiarity. This method has been put into practice in worldwide contests to show astounding feats, such as perfectly memorizing hundreds of images or thousands of numbers in under an hour, which reveal the unbounded capabilities of human memory [4]. For these individuals competing in memory competitions, their mental palaces are much simpler than one would expect: some may use their house, or others the location of their college graduation. However, they possess the ability of being able to reconstruct that location, then integrate it with different objects connected through new pathways to invent a powerful memory palace [4]. Much of its aptitude is already being utilized by some memory champions, who continue to set such records.While these memory competitions do not accurately represent the real world, they still exemplify how dominating the MOL can be as opposed to other memorization techniques. It can hold great promise for increasing students’ potential for academic success. By harnessing the potential of spatial navigation in tandem with visual stimulation, the MOL can be a powerful tool for those who seek to expand the limits of human memory.

The Basics Behind Memory

The neurons in our brain are constantly making and breaking connections with other neurons to create a coherent network [5]. When you learn and memorize something new, scientists theorize that your brain undergoes a process called Hebbian plasticity, during which new connections are formed between neurons [6]. These connections can then be strengthened or weakened depending on how often they are activated. In a process called long-term potentiation (LTP), high frequency stimulation causes repeated synaptic activation that serves to further consolidate memory. Conversely, during long-term depression (LTD), the effects are opposite: low frequency stimulation of synapses causes occasional synaptic activation that serves to weaken memory consolidation [7]. To better understand this concept, think of the connection between two neurons as a piece of tape holding two objects together. As you learn, these objects are taped together. This connection represents our memory. Over time, the stickiness of the tape decreases, and your choice to apply a new layer of tape every so often keeps the objects bound together. If you let the tape weaken, the objects begin to separate, and eventually disconnect entirely. While the neural connections that form the foundation of memory take place largely within the hippocampus, memory is a delocalized function: the hippocampus maintains a balance with other areas of the brain when encoding and retrieving memories [7]. These brain-wide connections allow us to remember the emotional context and sensations that accompany our memories, among other things. Similarly, the MOL adds its own context that meshes with your memories.

The Memory Palace

The memory palace is built upon two basic components: images and places [4]. The more personal the location and eccentric the image, the greater your chances are to recall the palace [7]. In order to effectively harness this mnemonic technique, the initial steps should select items that you wish to memorize and place them in the location that serves as your memory palace. For example, we will work with “bananas” and “oranges” on a grocery list, and the bedroom you grew up in will host your palace. To begin, select objects present in your room that will be connected to the items: a lamp and desk. Create a path that connects the objects together: if the lamp is straight ahead of your door, and the desk in the opposite corner, your path to walk will be straight from the door to the lamp, then a diagonal from the lamp to the desk.

With the path then generated, you build an image of the items you wish to memorize. As memory champion Ed Cooke puts it, “By laying down elaborate, engaging, vivid images in your mind, it more or less guarantees that your brain is going to end up storing a robust, dependable memory. [4]” For example, say you had a pet monkey that passed when you were younger. To fit this into the palace, reshape your lamp into a tree, and picture your pet monkey jumping and screeching around on its branches while waving bananas around. You’ve incorporated your first item into the palace. Making leeway to your desk, you witness it morph into your high school basketball court– your favorite sport. Rather than watching a normal game, you see birds dropping oranges into the hoops. Now your second item is locked into the palace.

Both the locations and events had some element of familiarity and emotion associated with it; these factors help connect eccentric visuals to a path that constitutes your palace. Now that the unusual images have entered your memory, the final component to a fully functional palace is to retrace the steps you took, flawlessly. Exit and re-enter the palace, then mirror the process you initially underwent. In this manner, your memory palace forces you to revisit unconventional visual stimuli through spatial navigation, eventually transferring the information to long-term memory.

How Different Neural Structures Are Associated with Memory

Studies of brain activation in humans reveal that the hippocampus interacts with regions such as the temporal, parietal, occipital, and cerebellar cortices, allowing the brain to process various sensory information and form durable memories [8]. This lattice of neural connections is built by various external cues relating to your memories–what you see, hear, or feel during that moment. For example, the feeling when you’re falling asleep in the car and as the car makes that one turn, you know you’ve reached home. This is likely due to the familiarity–one of many external cues–behind the location. Similarly, the MOL takes the context behind certain events and adds its own to boost your memorization skill.

As an event unfolds, your brain begins processing the various sensory information associated with that event. These inputs have to be stored as memory—otherwise you wouldn’t be able to recall any stimuli you sensed. Initially, these stimuli are temporarily stored in the hippocampus as short-term memory [9]. When you manipulate these stimuli with intent to complete a cognitive task, potentially through the MOL, the information in short-term memory is referred to as working memory, thought to be a function of the prefrontal cortex (PFC) [10]. To then transform this into more permanent storage, your brain undergoes LTP, which is the constant strengthening of synapses that leads to a long-lasting increase in signaling between neurons [11]. Research has shown that repetitive activation of synapses in the hippocampus can increase synaptic strength, a characteristic of LTP [12]. Thus, using spatial navigation to repeatedly retrace your MOL can generate an effective memory palace by converting working memory to long-term memory. However, LTP is only one piece of the puzzle in this process— factors such as sleep can play a role in memory consolidation as well [13].

While the process of encoding memories is roughly identical in everyone, different triggers attach varied levels of importance to certain memories. Some events are easier to remember because they build upon familiar memories already firmly encoded in your brain. The PFC interacts with the hippocampus to integrate and encode current events in relation to prior knowledge [14]. By recalling memories already in long-term storage, this connection adds familiarity to the context behind the new memory being formed. Adding familiarity in context lets you recall certain events much quicker by simplifying the retrieval process; these cues let you gain quicker access to memories already stored in the hippocampus through signaling [15]. When you employ the MOL, you use familiar events to transition from locus to locus, using spatial navigation of a location you maintain some level of intimacy with to create a path between the events.

As you’ve surely noticed, your familiarity with a location is positively correlated with the number of times you’ve visited that location. This consistent interaction is facilitated by a unique combination of cells termed place cells that activate in your brain whenever you revisit a specific location. These cells mediate connections between your Lateral Entorhinal Cortex (LEC) and your hippocampus to integrate information regarding your current environment into your short-term memory [16]. As you continue to mentally revisit that location, through your palace, these cells continue to fire and build stronger synapses via LTP, slowly, but accurately, generating a cognitive map [17]. This unique connection aids in consolidating memories specific to locations in a highly effective manner.

Another way your brain prioritizes memories may be through associated emotions, processed in the limbic system. The amygdala, a key structure of the limbic system that is responsible for fear processing, boosts memory encoding by enhancing attention and perception and increases memory retention through release of stress hormones [18]. By associating emotions with memories, events become easier to recall due to these beneficial increases. While the amygdala undergoes the same synaptic plasticity used to form memories, it associates some of the fear you felt with the event itself [19]. The result? When you recall that event, you’ll remember the fear that came with it. Serotonin is an important neurotransmitter involved with emotional regulation. Recent research has found that blockading serotonin receptors can inhibit memory formation and reinforcement through the disruption of neuronal connections— also influenced by serotonin receptor ligands [20].

However, strong emotional connections aren’t only associated with events, but also locations. As you develop an emotional connection to a place such as home, some of the happiness you feel is processed primarily by your limbic system in a similar manner as the amygdala. Because each memory palace is unique, it’s important to note that the method in which you construct a memory palace is also variable; you don’t have to construct your palace following the exact same steps and processes each time. Some general guidelines can help empower the palace’s effectiveness. Even though you simply require a location to navigate, memory champion Ed Cooke points out that choosing an intimate location is crucial to constructing an effective palace [6].

Furthermore, the MOL doesn’t resemble other mnemonics when it comes to assisting memory because it adds meaning to the information you want to remember. Unlike the MOL, basic mnemonics such as ROYGBIV for the colors of the rainbow or FANBOYS for conjunctions produce less intense contextual components to a memory, which is why the MOL organizes information in a manner that is easier to reproduce. However, adding this layer of complexity also requires extra effort from your brain. Two central structures, the superior parietal lobule (SPL) and the retrosplenial cortex (RSC), communicate in order for this to happen. Firstly, your RSC, which has close links with your occipital lobe, processes the features of the environment and the spatial relationship among them [21]. This way, you’re able to accurately navigate through your palace. Once your RSC has helped set the path, the SPL takes care of the rest. Located near your occipital cortex, the SPL is involved in visuospatial perception, including the representation and manipulation of objects in the mind [22]. When these structures assist the neural network of memory, you are able to create a memory palace in which you can mentally visualize objects and revisit them as a means of memorizing them.

‌The Power of Visual Memory

When you read a novel, you’re likely to conjure accompanying visuals to match the words. Associated visuals allow for the meaning of events to be accessed faster than with just words [23]. Since the MOL is heavily dependent on associating meaning with events, imbuing the memory palace with visuals enhances its power. Visual memory itself involves activity across a large neural network inclusive of various frontal areas, the hippocampus, and sensory cortices [24]. Regions such as your frontal cortex play a general role in the formation or manipulation of mental images; however, it has no bearing in constructing the content of the visuals. The hippocampus is likely required to form complex or spatially distributed images with rich detail. Without these, the images in your palace would seem chaotic and incomprehensible . The visual cortex has its hands full in helping perceive and decode the content of these images, giving the palace context and thus its effectiveness for boosting memory capabilities [24]. Each of these structures come together in a coherent network to help you create and make sense of the contents and space in your memory palace.

The images in your palace may be more defined than words because visuals are dually encoded while words are singularly encoded—meaning that images engage deeper levels of processing than words. This is the result of the Picture Superiority Effect: your brain processes words only through a verbal pathway, while images are processed through an image pathway in conjunction with the verbal code [25]. Thus, pictures tend to engage multiple representations and associations with other knowledge about the world, encouraging a more elaborate encoding of memory [26]. As you use the MOL, your brain employs visual memory in tandem with spatial relations [27]. This collaboration allows you to walk through your memory palace instead of blindly memorizing words.

Clearly, the memory champions who utilized this method, such as Ed Cooke, boasted more impressive cognitive skills. In 2002, researchers set out to understand why some individuals had superior memory capabilities than others [28]. To see whether superior memorizers were born differently from the average person, these researchers employed structural and functional brain imaging to see how the MOL generated activity across the brain. Through Magnetic Resonance Imaging (MRI) scans, researchers were able to produce detailed pictures of an individual’s brain. The scientists coupled this with fMRI scans to identify the neural structures that displayed activity and the frequency of that activity while the MOL was used. This combination helped researchers uncover that using the MOL produced greater brain activity in memory-inducing regions such as the hippocampus. In addition, the scientists conducted neuropsychological testing to confirm that the superior memorizers were not born with exceptional cognitive abilities compared to the other subjects —meaning there was no major difference in brain structure or intellectual ability [28]. This study implied that the power of the memory palace is not attributed to genetics.

Future Prospects

The conclusions of Maguire, Valentine, Wilding, and Kapur’s study held major implications for the general public. If there is no intrinsic tendency for certain individuals to display a stronger memory palace, then anyone is capable of harnessing its power to strengthen their memorization skills. It’s accessibility to the public makes it both a commonly used and effective technique. Because of that, any enhancement to the MOL can serve as extremely beneficial for students, who are constantly learning new things. To discover which factors can specifically increase the efficacy of the MOL, a 2021 study utilized a virtual memory palace (vMOL) on students aged 17 to 29 [29]. They were split into two groups, one assigned to a normal computer screen, and the other assigned to immersive virtual reality (VR) gear. Both groups were shown a room. Giving both groups equal opportunity to familiarize themselves with the given location, they were then provided with a list of words to recite. The study discovered that the students using VR to construct a memory palace exhibited superior memory because their level of immersion with the palace was greater [29]. However, immersion is only one of many components that can alter how your memory palace serves you. Harnessing the power of the MOL in educational settings is still being further explored and examined to see if it can effectively match current learning standards. As research moves forwards, the benefit it provides for students is becoming more prevalent.

Memory remains one of neuroscience’s major frontiers and one of the most crucial aspects of our daily lives. With so many factors at play, isolating the different ways we can employ memory to our advantage is a hidden treasure. Emotions, familiarity, and immersion are just the beginning of this vast expanse, which anyone can tread. Ed Cooke sticks by this idea that even the average person’s memory is remarkably powerful if used properly [18]. Seemingly superhuman feats performed by memory champions support this. Past records involved memorizing 4620 digits or 2530 playing cards in a mere hour. The 2014 memory champion, Ben Pridmore, held in his brain 50,000 digits of pi. The amount of information the MOL allows you to absorb seems extraordinary at first glance; it is constantly expanding the periphery of human memory. It helps make the impossible, possible. As you continue to learn and consolidate information about the world around you, don’t forget to walk through the treasure tucked away within the palace in your brain—one as powerful as your imagination. By utilizing the MOL, maybe you can be the next record holder to memorize a deck of cards in under a minute.

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