Sometimes, as with epileptic seizures, head trauma, or hallucinogenic intoxication, it is possible to experience memories of the past very vividly, as if they were happening in the present. This relatively little studied phenomenon is called “ecmnesia”.
In this article we will define the main characteristics of ecmnesia and explain what are its causes. We will also talk about Paramnesis, other particular phenomena related to memory, such as flash memories or cryptoamnesia.
Ecmnesia: definition and characteristics
Ecmnesia is a perception disorder that consists of experience situations that have happened in the past as if they were happening in the present. These experiences have a very intense vividness and while they are happening the person behaves as they would if they were really there, with great emotional involvement.
This is why ecmnesia can be considered a type of hallucinatory experience, although this phenomenon is often mentioned in the scientific literature on the psychology of memory. On another side, the concept of “ecmnesic delirium” highlights the delusional content of these experiences, Because often the one who believes them really lives them.
Ecmnesia does not always have a pathological character, but its clinical consideration depends on the context in which it occurs. For example, if they appear due to the occasional use of a hallucinogenic drug, these experiences might not be properly understood as memory impairments.
Sometimes the term ecmnesia it is also used to denote other memory alterations which are not always linked to hallucinations. Specifically, some medical dictionaries define ecmnesia as the loss of recent memories, while others add that memory is retained for the distant past.
The frequency of ecmnesia is very low. Experiments of this type have been described in cases of brain damage, especially different forms of dementia, Which damage the tissues of the nervous system causing alterations in consciousness, cognition and memory.
Other biological disorders associated with ecmnesia are delirium or delirium, which frequently occurs in hospitalized elderly people, and twilight states of temporary epilepsy. These transient phenomena are characterized by an alteration of consciousness which prevents the correct perception of the environment.
There are several types of substances with hallucinogenic effects that can cause perceptual alterations similar to those we have described. Some of the most well-known hallucinogenic drugs are mushrooms containing psilocybin, mescaline (Found in the peyote cactus) and lysergic acid or LSD.
The psychological literature also links ecmnesia with hysteria, although this diagnostic category has been dropped over time. In these cases, the reminiscence is more likely to be due to auto-suggestion and not to biological factors, as is the case with drugs or brain damage.
Other similar phenomena: Paramnesis
Ecmnesia is classified as paraamnesia, Term used to describe memory alterations that include false memories and / or poor perception of time context. Other authors include ecmnesia in the hypermnesia group, an ambiguous concept regarding the presence of abnormally clear memories.
Below we will briefly describe the main characteristics of 5 other types of paraamnesis: pseudorecuerdos (plot and fantasy pseudology), déjà vu and its opposite, never seen, reduplicating paraamnesia, cryptoamnesia and flash memory.
1. Fantastic conspiracy and pseudology
These two phenomena are pseudo-memories: they consist in the spontaneous and involuntary creation of false memories to fill the gaps of the memory. Conspiracy is the basic form and is associated with Wernicke-Korsakoff syndrome, while fantastic pseudology is characterized by impossible narratives and appears in Münchausen syndrome.
2. Already seen and never seen
The famous déjà vu occurs when, faced with a new experience, one has the feeling of having already lived it. It is associated with fatigue, depersonalization and epilepsy. Conversely, the never seen that we already know does not generate a feeling of familiarity.
3. Reduction of redundancy
Reduplicative paramnesia consists of the feeling that a place or a person is known who is in fact unknown to the subject; the classic example is that of a hospital. Still reminiscent of déjà vu, this phenomenon is rather associated with pseudo-memories and appears in Korsakoff syndrome, dementia and confusional states.
Towards cryptoamnesia a memory is wrongly perceived as a new production. This is very common in fields such as art or science: semantic memory appears without also retrieving the context in which it was generated from memory, so it is believed that there was an idea or a thought that actually comes from another person.
5. Flash memory
Flash memories are recorded very vividly due to the impact of the situation on the person. A typical example is remembering what was done during the attack on the Twin Towers. Memories of traumatic episodes could also be conceived of as flash memories, and rarely as ecstasy.