Transient global amnesia: symptoms and causes
Although we usually talk about memory as if it were a whole, the truth is that there are several types of memory, each with its own internal logic. In addition, each of these memories stores a different kind of information. For example, emotional memory stores information related to the emotional state, while the declarative works with information that can be verbalized.
Just as there are different forms of memory, amnesia, which is a harmful alteration in the functioning of this cognitive process, does not always manifest in the same way.
In this article we will see the characteristics of transient global amnesia , one of the strangest memory disorders.
- Related article: "The different types of amnesia (and its characteristics)"
What is transient global amnesia?
We know as transient global amnesia a disorder by which the person is not able to remember the events that he has lived during the last minutes or hours and some unimportant information about what happened to him long ago, although he preserves the memories related to his own identity and is able to form new memories.
Thus, the symptoms of this type of amnesia focus on the past, and not on the ability to transform events of the present into memories. It is therefore a question of a retrograde amnesia , because it only affects the recovery of memories already stored.
Thus, a person with transient global amnesia may ask "how did I get here?" and not knowing what has happened during his displacement to the place he occupies in the present, and he does remember his name and, probably his characteristics and personality traits, family ties and friendships, place of work, etc.
- You may be interested: "Types of memory: how does memory store the human brain?"
The main symptoms of transient global amnesia are the following:
- Anxiety by not remembering the most recent events
- It is frequent anger and the feeling that "someone has played me a joke"
On the other hand, it should also be noted that during the crises produced by this type of amnesia a person does not lose consciousness at any time, as any witness can assure if there is one.
In addition, the symptoms of transient global amnesia dThey should disappear before 24 hours have passed from the beginning (normally they do not last more than 8 hours), and other cognitive functions must not be damaged. Furthermore, during this attack of amnesia, symptoms associated with epilepsy should not appear either.
In case these last criteria are not met, it is considered that another type of amnesia has been suffered.
Course of this disorder
Transient global amnesia comes abruptly and, as we have seen, without loss of consciousness. As time passes, normally starting two hours from its beginning, the memories that had been "blocked" are again accessible , gradually (the first to be "recovered" tend to be the oldest).
The causes that produce the transitory global amnesia are not clear, and probably there is not only one, but several.
For example, it has been hypothesized that in some cases their symptoms may be due to a deficiency of the blood supply in small parts of the brain , so that there are no detectable sequelae.
Small ischemic accidents could cause the cognitive abilities that take place in the brain to be blocked or even impeded for a while, until this set of organs is able to recover from this problem.
On the other hand, it is also possible that certain traumatic events may affect memory. However, this explanation has a flaw, as we will see.
Differences with other memory disorders
Keep in mind that transient global amnesia it is relatively benign, since its effects disappear in a few hours and by definition it does not leave sequels. However, it can become confused with other types of amnesia. A similar effect could occur with great efforts or sudden changes in temperature.
In global amnesia, for example, many things are forgotten about what happened in the past, but this information will not be recovered. On the other hand, in drug-induced amnesia, a specific cause is known to produce the symptoms.
Regarding traumatic events, we know that they are capable of causing us to store information about what is happening in the present for a time, due to the secretion of corticoids over an area of the brain known as hippocampus.However, this is not what happens in transient global amnesia, since in the latter the problem is in accessing stored memories, not in storing new memories. Therefore, its character is purely retroactive, while the stress of traumatic moments has effects in the form of anterograde amnesia, which is known.