Today’s topic of choice is another group of people with amazing memories- Mnemonists. Unlike the people with developmental disorders that I talked about a few weeks ago, mnemonists don’t often have physical brain differences to explain their memory abilities (apart from a small difference in the area linked to memorising long lists of numbers, which seems more of an effect than a cause).

Instead, their memories are so strong due to practice, and the use of Mnemonic techniques. Almost everyone has used some kind of mnemonic before; for example, SOHCAHTOA (for remembering when to use sin, cos, and tan in a triangle), or Richard Of York Gave Battle In Vain (for remembering the colours of the rainbow).However, the method used by mnemonists are much more detailed and involved than this.

One mnemonic strategy is the major system; in this, each number between 0-9 is assigned a consonant sound. These are used to construct words (vowels are unassigned and used to connect consonants together) and visual images from the numbers that need to be remembered. And if that sounds complicated, the major system is one of the simpler ones!

Mnemonists can accomplish remarkable things, like the ones on this list, but does that mean they have a true eidetic (photographic) memory?

Many researchers would say no, as their understanding splits memory into two areas; natural, and artificial. Mnemonic training only increases the artificial part of memory, not its natural state: a true eidetic memory would be from the natural memory. Also, every single winner of the World Memory Championships has been a Mnemonist, not someone claiming a true eidetic memory.

A major difference between an accurate memory and an eidetic memory is that a good memory stores an image of an event or situation, exactly recalling according to that image. However, an eidetic memory not only remembers the details they encoded when making the memory, but can find new details the next time they recall it.

One theory of why this can happen is that for some reason incoming sensory information doesn’t get processed, but remains in its raw state instead. This means the next time it is recalled, it is very slightly reprocessed- just enough for some new details and context to be available.

Researchers have occasionally tried to test for photographic memory experimentally, but that has never worked out well; the only person who was able to solve one photographic memory challenge ended up marrying the experimenter, who then refused to do further experiments on her.

However, that still doesn’t make it impossible for someone to have an eidetic memory, it just means the question, like most of the ones in psychology, can’t yet be answered.