Hypermnesia sometimes makes people envious. However, this condition does not only have daily advantages… In concrete terms, people with hypermnesia involuntarily record many memories: for example, they are able to remember the precise date of a plane crash or a political decision, without the slightest effort. A situation that quickly turns out to be oppressive. What can be the consequences of this disorder? Can we support it? Answers from Pr Mathieu Ceccaldi, neurologist and teacher at the Faculty of Medical and Paramedical Sciences of Marseille.
Reminder: how does memory work?
The memory means our ability to record, process, store and retrieve information related to our past experiences. It is a complex process that involves several parts of the brain and allows everyone to remember events, people, places and things they have seen or experienced in the past. She allows us learn and reason to better adapt to our environment. There are several types of memory, which can be classified according to their function or duration:
- working memoryor memory of the present (short memory): that which makes it possible to manipulate and retain information during the performance of a task or activity.
- episodic memory (long and explicit memory): one that allows a person to remember specific events in their personal life, such as happy times or difficult times.
- semantic memory (long and explicit memory): one that allows a person to retain general or abstract information, such as facts, knowledge or concepts.
- procedural memory (long and implicit memory): that which allows a person to retain automatisms such as walking, driving or speaking.
- Perceptual memory (long and implicit memory) : the one that relies on our senses and allows us to retain images or noises without realizing it. It is this memory in particular that allows us to retain faces, voices, places, etc.
Definition: what is a person with hypermnesia?
Hypermnesia is a extremely rare memory pathology, says Professor Mathieu Ceccaldi. According to the Esanum medical community, it was first described in the 19th century (source 1).
“People with hypermnesia have a outstanding memory : they are able to remember extremely precise details and to retain them without difficulty over a period much longer than normal”, explains the neurologist.
The patients concerned are in fact prey to a dysfunction of the hierarchy of information. Some doctors speak of “memory enhancement”, which stores too much non-essential information.
A key point to remember: hypermnesiacs do not choose the memories they store! They also fail to restrain them when they arise.
The memory is often autobiographical and the elements occur in the manner of “flash” without having been solicited, specifies Professor Ceccaldi.
What is the opposite of hypermnesia?
The opposite of hypermnesia is l’amnesia, that is, the inability to remember things that have been read, seen or felt before. It can be caused by an illness, injury or traumatic event, and lead to partial or total loss of memory.
The different types of hypermnesia
There are mainly two types of hypermnesia:
- hypermnesia autobiography (the “true” hypermnesia), characterized by an ability to remember very precisely details related to one’s life
- et late paroxysmal emotional hypermnesia or post-traumatic stress disorder.
Autobiographical hypermnesia (or hyperthymesia)
Autobiographical hypermnesia or hyperthymesia refers to the extraordinary ability to remember precise details of his childhood, adolescence or adult life.
In the 2000s, Jill Price, a 30-something American, became one of the first people with hyperthymesia to be the subject of extensive clinical study and scientific publications. Nicknamed “the woman who can’t forget”she has long collaborated with James McGaugh, head of the neuroscience laboratory at the University of California.
Late paroxysmal emotional hypermnesia (or post-traumatic stress disorder)
Late paroxysmal emotional hypermnesia, or post-traumatic stress disorder, refers, as its name suggests, to an ingrained trauma that haunts patients. The traumatic scene resurfaces unexpectedly and attacks said patients (victims or witnesses) who have the impression of reliving it live (images, sounds, voices, smells, etc.). It can be linked to all sorts of violent events: attacks, wars, kidnappings, sexual assaultetc.
Autism: some patients have a particular form of highly developed memory
Some people with autism spectrum disorder are also considered to have hypermnesic abilities: “they have the ability to memorize very precisely and reproduce almost all of a book they have read, or a place they have visited“, assures Professor Ceccaldi. However, this condition is not common in autistic people and is not part of the diagnostic criteria for autism!
What is Targowla Syndrome
Some people with Targowla syndrome may also have hypermnesia. This rare condition is indeed characterized by an exceptional memory. It was reported following the Second World War and often affects former concentration camp deportees. Patients usually suffer from associated behavioral problems, such asanxiety or depression.
What are the causes of this “total” memory?
Researchers believe that hypermnesia is linked to a dysfunction between short-term memory and long-term memory: the buffer, which would normally clear, migrates into the long-term memory area for some unknown reason (source 1).
A recent study, relayed in 2021 by the blog Biomedical Realities of the World (source 2) looked at the case of a hypermnesic Italian octogenarian. She reveals that the MRI of her brain showed no abnormalities (the brain was not a particular size and none of its areas were larger than normal).
In the case of another man, documented in 2018, however, the MRI detected “greater than normal connectivity between the left hippocampus and several left cortical regions“. But this might be the consequence – and not the cause – of hypermnesia… Research is therefore continuing.
In addition, several neurological and mental disorders might be linked to this memory particularity: de Targowl syndromethe semantic dementiabut also the dyslexiaTHE obsessive compulsive disorder (OCD), the attention deficit hyperactivity disorder (ADHD), or autism spectrum disorder.
Symptoms: how do you know if you have hypermnesia? Is there a test?
There aren’t really any tests that can “diagnose” hypermnesia.
Data subjects can remember distant periods of their life, dating back to early childhood. These memories are mainly visual, but sometimes sound, olfactory, tactile, with memories of sensations that are sometimes associated with them. They are also very good at retaining information, such as dates, names, faces, events, etc.
As noted above, people with hyperthymesia often present with symptoms of obsessive-compulsive disorder (OCD).
Whether or not they are suffering from post-traumatic stress, they can also manifest:
What are the consequences of such a phenomenon?
The tone is set from the beginning of this article, hypermnesia cannot be considered a “gift”. On the contrary, it can become very disabling, even paralyzing. In some cases, it even becomes a psychopathological problem, characterized by permanent anxiety and anguish, notes Professor Ceccaldi. A real burden. And to emphasize:
Paradoxically, these people are so overwhelmed by their memories that they may be less good cognitively.
In other words, people with hypermnesia will not necessarily find it easier to remember a shopping list.
How to become hypermnesic and improve your memory?
It is impossible to become hypermnesiac. On the other hand, you can completely improve your memorization capacities: the memory can be trained, and thus increase. Otherwise, you can use mnemonic devices.
Treatment: can hypermnesia be treated? How ?
Cases of autobiographical hypermnesia are extremely rare, recalls the neurologist, and no epidemiological study has yet been conducted on this subject. There is no specific treatment and management is done on a case-by-case basis.depending on the impact of this disorder on the lives of patients.
People in the throes of paralyzing anxiety or a depressive syndrome can benefit from psychological support. At the same time, they can also consider a medication treatment to decrease anxiety or help them sleep better.
In addition, in the case of emotional hypermnesia, treatment includes techniques such as EMDR (Eye Movement Desentitization and Reprocessing) or cognitive and behavioral therapies (CBT). Objective : help patients come to terms with the traumatic events they have experienced – not to forget them.
