While we usually talk about memory as a whole, the truth is that there are several types of memory, each with their own internal logic. In addition, each of these memories stores a different type of information. For example, emotional memory stores information about emotional state, while declarative works with information that can be verbalized.
Since there are different forms of memory, amnesia, which is a harmful alteration in the functioning of this cognitive process, does not always manifest itself in the same way.
In this article we will examine the characteristics of transient global amnesia, One of the strangest memory disorders.
What is transient global amnesia?
We know it as transient global amnesia a disorder in which the person is unable to remember the events they have experienced for the last few minutes or hours and some irrelevant information about what happened to him a long time ago, although he retains 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 turn events in the present into memories. It is therefore retrograde amnesia, Because it only affects the recovery of memories already stored.
So, a person with transient global amnesia may wonder “how did I get here?” and not knowing what happened on his journey to his place in the present, and whether he remembers his name and possibly his characteristics and personality traits, family ties and friends, their place of work, etc.
The main symptoms of transient global amnesia are:
- anxiety by not remembering the most recent events
- it is common anger and the feeling that “someone made a joke of me”
On the other hand, it should also be noted that during crises caused by this type of amnesia, a person does not lose consciousness at any time, as any witness can be insured in the event that there were any.
In addition, the symptoms of transient global amnesia dthey should disappear within 24 hours as soon as it appears (usually lasts no more than 8 hours) and no other cognitive function should be impaired. In addition, the symptoms associated with epilepsy should not appear during this attack of amnesia.
In the event that these latter criteria are not met, another type of amnesia is considered to have been suffered.
Evolution of this disorder
Transient global amnesia occurs suddenly and, as we have seen, without loss of consciousness. Over time, usually from two hours from the start, memories that had been “blocked” are accessible again, Gradually (the first to be “recovered” are generally the oldest).
The causes of transient global amnesia are unclear, and there is probably not one, but several.
For example, it has been hypothesized that in some cases their symptoms may be due to insufficient blood flow to small parts of the brain, So that there are no detectable sequelae.
Small ischemic attacks could cause the cognitive abilities that take place in the brain to be blocked or even hampered for a period of time, until this set of organs is able to recover from this problem.
On the other hand, it is also possible that some traumatic events affect memory. However, this explanation has a flaw, as we will see.
Differences from other memory disorders
It should be noted that transient global amnesia it is relatively benign, because its effects disappear in a few hours and by definition leaves no after-effects. However, it can be confused with other types of amnesia. A similar effect could occur with great effort or with sudden changes in temperature.
In global amnesia, for example, a lot is forgotten about what happened in the past, but this information will not be retrieved. On the other hand, in drug amnesia, a specific cause is known that produces the symptoms.
As for traumatic events, we know that they are capable of causing us not to store information on what is happening in the present for a while, due to the secretion of corticosteroids in an area of the brain known as the hippocampus. However, this is not what happens in transient global amnesia, because in the latter the problem is to access the memories and stored, not to store 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.