Method of loci

The method of loci (loci being Latin for "places"^[1]), also called the memory palace or mind palace technique, is a mnemonic device adopted in ancient Roman and Greek rhetorical treatises (in the anonymous Rhetorica ad Herennium, Cicero's De Oratore, and Quintilian's Institutio Oratoria). In basic terms, it is a method of memory enhancement which uses visualization to organize and recall information. A lot of memory contest champions claim to use this technique to recall faces, digits, and lists of words. These champions’ successes have little to do with brain structure or intelligence, but more to do with their technique of using regions of their brain that have to do with spatial learning.^[2]

The term is most often found in specialised works on psychology, neurobiology, and memory, though it was used in the same general way at least as early as the first half of the nineteenth century in works on rhetoric, logic, and philosophy.^[3] John O'Keefe and Lynn Nadel refer to:

'the method of loci', an imaginal technique known to the ancient Greeks and Romans and described by Yates (1966) in her book The Art of Memory as well as by Luria (1969). In this technique the subject memorizes the layout of some building, or the arrangement of shops on a street, or any geographical entity which is composed of a number of discrete loci. When desiring to remember a set of items the subject 'walks' through these loci in their imagination and commits an item to each one by forming an image between the item and any distinguishing feature of that locus. Retrieval of items is achieved by 'walking' through the loci, allowing the latter to activate the desired items. The efficacy of this technique has been well established (Ross and Lawrence 1968, Crovitz 1969, 1971, Briggs, Hawkins and Crovitz 1970, Lea 1975), as is the minimal interference seen with its use.^[4]

The items to be remembered in this mnemonic system are mentally associated with specific physical locations.^[5] The method relies on memorized spatial relationships to establish, order, and recollect memorial content. It is also known as the "Journey Method," used for storing lists of related items, or the "Roman Room" technique, which is most effective for storing unrelated information.^[6]

Contemporary usage

Many effective memorisers today use the "method of loci" to some degree. Contemporary memory competition was initiated in 1991 and the first United States championship was held in 1997.^[7] Part of the competition requires committing to memory and recalling a sequence of digits, two-digit numbers, alphabetic letters, or playing cards. In a simple method of doing this, contestants, using various strategies well before competing, commit to long-term memory a unique vivid image associated with each item. They have also committed to long-term memory a familiar route with firmly established stop-points or loci. Then in the competition they need only deposit the image that they have associated with each item at the loci. To recall, they retrace the route, "stop" at each locus, and "observe" the image. They then translate this back to the associated item.

Memory champions elaborate on this by combining images. Eight-time World Memory Champion Dominic O'Brien uses this technique.^[8] The 2006 World Memory Champion, Clemens Mayer from Germany, used a 300-point-long journey through his house for his world record in "number half marathon", memorising 1040 random digits in a half hour. Gary Shang has used the method of loci to memorise pi to over 65,536 digits.^[9]

Using this technique a person with ordinary memorisation capabilities, after establishing the route stop-points and committing the associated images to long-term memory, with less than an hour of practice, can remember the sequence of a shuffled deck of cards. The world record for this is held by Simon Reinhard at 21.19 seconds.^[10]

The technique is taught as a metacognitive technique in learning-to-learn courses. It is generally applied to encoding the key ideas of a subject. Two approaches are:

1. Link the key ideas of a subject and then deep-learn those key ideas in relation to each other, and
2. Think through the key ideas of a subject in depth, re-arrange the ideas in relation to an argument, then link the ideas to loci in good order.

The Rhetorica ad Herennium and most other sources recommend that the method of loci should be integrated with elaborative encoding (i.e., adding visual, auditory, or other details) to strengthen memory. However, due to the strength of spatial memory, simply mentally placing objects in real or imagined locations without further elaboration can be effective for simple associations.

A variation of the "method of loci" involves creating imaginary locations (houses, palaces, roads, and cities) to which the same procedure is applied. It is accepted that there is a greater cost involved in the initial setup, but thereafter the performance is in line with the standard loci method. The purported advantage is to create towns and cities that each represent a topic or an area of study, thus offering an efficient filing of the information and an easy path for the regular review necessary for long term memory storage.^[11]

Something that is likely a reference to the "method of loci" techniques survives to this day in the common English phrases "in the first place", "in the second place", and so forth.^[12]

Applicability of the term

The designation is not used with strict consistency. In some cases it refers broadly to what is otherwise known as the art of memory, the origins of which are related, according to tradition, in the story of Simonides of Ceos and the collapsing banquet hall.^[13] For example, after relating the story of how Simonides relied on remembered seating arrangements to call to mind the faces of recently deceased guests, Stephen M. Kosslyn remarks "[t]his insight led to the development of a technique the Greeks called the method of loci, which is a systematic way of improving one's memory by using imagery."^[14] Skoyles and Sagan indicate that "an ancient technique of memorization called Method of Loci, by which memories are referenced directly onto spatial maps" originated with the story of Simonides.^[15] Referring to mnemonic methods, Verlee Williams mentions, "One such strategy is the 'loci' method, which was developed by Simonides, a Greek poet of the fifth and sixth centuries BC"^[16] Loftus cites the foundation story of Simonides (more or less taken from Frances Yates) and describes some of the most basic aspects of the use of space in the art of memory. She states, "This particular mnemonic technique has come to be called the "method of loci".^[17] While place or position certainly figured prominently in ancient mnemonic techniques, no designation equivalent to "method of loci" was used exclusively to refer to mnemonic schemes relying upon space for organization.^[18]

In other cases the designation is generally consistent, but more specific: "The Method of Loci is a Mnemonic Device involving the creation of a Visual Map of one's house."^[19]

This term can be misleading: the ancient principles and techniques of the art of memory, hastily glossed in some of the works cited above, depended equally upon images and places. The designator "method of loci" does not convey the equal weight placed on both elements. Training in the art or arts of memory as a whole, as attested in classical antiquity, was far more inclusive and comprehensive in the treatment of this subject.

Spatial mnemonics and specific brain activation

Brain scans of "superior memorizers", 90% of whom use the method of loci technique, have shown that it involves activation of regions of the brain involved in spatial awareness, such as the medial parietal cortex, retrosplenial cortex, and the right posterior hippocampus.^[20][21]

The medial parietal cortex is most associated with encoding and retrieving of information. Patients who have medial parietal cortex damage have trouble linking landmarks with certain locations; many of these patients are unable to give or follow directions and often get lost. The retrosplenial cortex is also linked to memory and navigation. In one study on the effects of selective granular retrosplenial cortex lesions in rats, the researcher found that damage to the retrosplenial cortex lead to impaired spatial learning abilities. Rats with damage to this area failed to recall which areas of the maze they had already visited, rarely explored different arms of the maze, almost never recalled the maze in future trials, and took longer to reach the end of the maze, as compared to rats with a fully working retrosplenial cortex.

In a classic study in cognitive neuroscience, O'Keefe and Nadel proposed "that the hippocampus is the core of a neural memory system providing an objective spatial framework within which the items and events of an organism's experience are located and interrelated."<ref This theory has generated considerable debate and further experiment. It has been noted that "[t]he hippocampus underpins our ability to navigate, to form and recollect memories, and to imagine future experiences. How activity across millions of hippocampal neurons supports these functions is a fundamental question in neuroscience, wherein the size, sparseness, and organization of the hippocampal neural code are debated.":^[22]

The technique is also used for second language vocabulary learning as polyglot, Timothy Doner, described in his 2014 TED (conference) talk. ^[23]

In popular culture

Literature

• In the 1981 fantasy novel Little, Big by John Crowley, advisor-mage Ariel Hawksquill uses the method to link obscure information to aid her clients, and notes that:

"...the greatest practitioners of the old art discovered some odd things about their memory houses the longer they lived in them ... it was discovered, for instance, that the symbolic figures with vivid expressions, once installed in their proper places, are subject to subtle change as they stand waiting to be called forth... also, as the memory house grows, it makes conjunctions and vistas that its builder can't conceive of beforehand..."

• The technique is employed by fictional character Hannibal Lecter in Hannibal and Hannibal Rising, novels by American author Thomas Harris. In several passages in these books, Lecter is described as mentally walking through an elaborate memory palace to recall information, mentally escape unpleasant situations and enhance sensory perceptions.^[24]

• In The Enchantress of Florence by Salman Rushdie, a character is said to be a memory palace; at first she has only the memories of the Pasha, being intended as a storage space for his stories. Her "last story" is her own tale of her indoctrination.

• The technique is depicted in the Matthew Reilly book Scarecrow and the Army of Thieves. The main character, Shane Schofield, uses the technique to lock away good memories and prevent psychological torture.

• The technique is mentioned in Hilary Mantel's book Wolf Hall. The protagonist, Thomas Cromwell, uses the technique, and makes reference to Cicero's story of Simonides of Ceos remembering the locations of all the guests after he escapes being crushed by the collapsing roof.

• The technique is also the main focus of the book Moonwalking with Einstein by Joshua Foer.

• The technique is often used by Aloysius Pendergast, the protagonist of a series of novels by Douglas Preston and Lincoln Child.

• Derren Brown, in his book Tricks of the Mind, demonstrated how to use the Loci system in conjunction with a linking and number-pegging system. He demonstrated the technique in the Channel Four series Trick of the Mind.

Television

• The technique was depicted in the BBC television series Sherlock in the second episode of the second series, "The Hounds of Baskerville", where Sherlock Holmes uses his "mind palace" to seek and reassemble important facts and associations in his memory which were relevant to the case. In "The Empty Hearse," the first episode of its third series, Sherlock pretends to access his mind palace in order to defuse a bomb. The method is also seen again in episodes two and three of series three. In episode two, "The Sign of Three", he uses the "mind palace" to organize an interrogation; in episode three, "His Last Vow", Sherlock again uses the technique to survive being shot in the abdomen. In this episode, the technique is also used by the main antagonist, Charles Augustus Magnussen, as a method of storing vast amounts of blackmail material.

• Holmes uses the method of loci to recall where he heard a phrase in CBS' Sherlock Holmes adaptation Elementary, in the episode "The Long Fuse."

• The memory palace concept is also used in several episodes of the CBS series The Mentalist by the title character, Patrick Jane, to help colleagues and witnesses remember things such as playing card locations in a deck or information and names of guests at a party.

• The memory palace concept is also used in several episodes of the CBS series Criminal Minds by a Supervisory Special Agent Dr. Spencer Reid (portrayed by Matthew Gray Gubler).

• The concept was illustrated in the episode of the documentary television series, The Day the Universe Changed titled "A Matter of Fact", in which James Burke explains how it was used in medieval times when literacy was rare for sophisticated scholastic and business affairs.

• In the series Leverage, the protagonists execute a con revolving around the concept of a Roman Room ("The Reunion Job").

• Will Graham in NBC's Hannibal uses a "mind palace" to escape from his surroundings and retain some sanity in Season 2.

• Commander William Adama uses this technique in the re-imagined Battlestar Galactica in the episode "A Day in the Life". He uses the technique to remember the name of his aide, a young Private who brings him coffee.

Film

• A version of the technique, dubbed "The Memory Warehouse", appears in the 2003 film Dreamcatcher, granted to the film's four main characters as a result of contact with an alien that takes the form of a young boy who calls himself "Dudditz". In the film, the Memory Warehouse is a place where all of the characters' thoughts and memories take the form of physical files that can be interacted with, and burned when necessary. The character Jonesy keeps an entire section of the Memory Warehouse dedicated specifically to his memories and theories regarding Dudditz, which he must recover and hide after an antagonistic alien takes over his body.

Visual Arts

• Memory Palace, an exhibition at the Contemporary Arts Center, in Cincinnati, Ohio.

Notes

References

• Yates, Frances A. (1966). The Art of Memory. Chicago: University of Chicago Press. ISBN 0226950018. 
• Brown, Derren (2007). Tricks of the Mind. London: Transworld publishers. 
• Spence, Jonathan D. (1984). The Memory Palace of Matteo Ricci. New York: Viking Penguin. ISBN 0-14-008098-8. 
• Carruthers, Mary (1990). The Book of Memory. Cambridge University Press. ISBN 0521716314. 
• Carruthers, Mary (1998). The Craft of Thought. Cambridge University Press. ISBN 0521795419. 
• Rossi, Paolo (2000). Logic and the Art of Memory. University of Chicago Press. ISBN 0226728269. 
• Bolzoni, Lina (2001). The Gallery of Memory. University of Toronto Press. ISBN 0802043305. 
• Bolzoni, Lina (2004). The Web of Images. Ashgate Publishers. ISBN 0754605515. 
• Dudai, Yadin (2002). Memory from A to Z. Oxford University Press. ISBN 0198520875. 
• Small, Jocelyn P. (1997). Wax Tablets of the Mind. London: Routledge. ISBN 0415149835. 
• Carruthers, Mary; Ziolkowski, Jan (2002). The Medieval Craft of Memory: An anthology of texts and pictures. University of Pennsylvania Press. ISBN 0812218817. 
• Dann, Jack (1995) The Memory Cathedral: A Secret History of Leonardo da Vinci: Bantam Books 0553378570
• Foer, Joshua (2011). Moonwalking with Einstein: The Art and Science of Remembering Everything. New York: Penguin Press. ISBN 978-1-59420-229-2.