What is the meaning of Amnesia? Concept, Definition of Amnesia

Definition of Amnesia


1. Concept of Amnesia

Amnesia (from Greek Ἀμνησία amnesia, oblivion) is a disorder of the functioning of memory, during which the individual is unable to retain or recover information previously stored. The causes of amnesia are organic or functional. The organic include damage to the brain, caused by disease or trauma, or use of certain (generally sedative) drugs. The functional are psychological factors, such as defense mechanisms. Hysterical post-traumatic amnesia is an example of this factor. Amnesia can be also spontaneous, in the case of transient global amnesia (TGA for its acronym in English) has highest rate of cases in people between the middle ages and old age, particularly males, and usually lasts less than 20 hours.
According to their chronological order classification
Amnesia • anterograde. New events not are transferred to long-term memory, so the one who suffers it will not be able to remember anything that occurred after the onset of this type of amnesia for more than a small moment. The complement of this is retrograde amnesia
• Retrograde amnesia. Not be remembered events that occurred before the onset of illness.
These terms are used to categorize symptoms, not to indicate a particular cause of etiology. Both categories of amnesia can occur at the same time in the patient, and are a result of damage to the brain regions that are closely associated with episodic/declarative memory: the Middle temporal lobes and especially the hippocampus.


2. Definition of Amnesia

Amnesia is a condition pretty recurrent that people suffer and which causes partial or total loss of the memories of the memory. For instance, is considered one of the most common and typical disorders who suffers from memory. Memory, is one of the most important functions that holds our brains and consists of store, give you a code to memories, to information that corresponds to the last time, then when it is necessary to evoke it.
When amnesia is present, the individual can not retrieve this information, i.e., presents serious problems when wanting to remember information, data, past images.
Noteworthy is that amnesia can occur for several reasons, one of the most common is after suffering a major impact in our heads, that damages the brain, we can remember. Also some diseases cause this impossibility of remembering and the use of some medications, usually the sedative.
On the other hand, there are purely psychological reasons that make a guy lose his memory and present amnesia, i.e. amnesia emerges as a mechanism Defense for not remembering any event, event, which normally has a highly negative charge to the sick, that it refuses to remember it.
And it is also common that the amnesia is present so spontaneous, i.e. not to respond to any of the above issues.
It is possible that we find different types of amnesia. A first classification makes the distinction in chronological terms and speaking of anterograde amnesia and retrograde amnesia. The first not recalled nothing of what happened after the onset of the disease while the second person will not remember what happened before the onset of the disease.
And etiologically different following types: post-traumatic amnesia (caused by a strong blow to the head), dissociative amnesia (is repressed memories by trauma involving), lacunar amnesia (a concrete situation makes us lose the memory), flight (caused by a trauma), the childhood amnesia (can be linked to unpleasant memories or lack of development in the brain), global amnesia (amnesia is complete), post hypnotic amnesia (a person undergoing hypnosis doesn't remember then certain events), source amnesia (remember information but does not know well how can remember it), the own memory distrust syndrome and medial diencephalic amnesia (caused by a lesion in medial diencephalon).


3 Concept of Amnesia

Before you can define this concept we must define the memory. Memory is the ability with which tells our Central nervous system to capture, organize, and fix our past events and is closely linked to the function of care. It is capable of storing data through ultra complex mechanisms that are developed in three stages: encoding, storage, and evocation. The presence of amnesia prevents this capacity to develop properly.
Amnesia is determined when someone has lost or has weakened the memory is checked. The person who suffers from this disorder is not able to store or retrieve information received in advance, whether it is organic or functional reasons.
Organic amnesia involves some kind of injury in the area of the brain, which can be caused by disease, trauma or by the abuse of certain drugs. Functional amnesia, on the other hand, appears by psychological factors, as a mechanism of defence (e.g., hysterical post-traumatic amnesia).
There are also cases of spontaneous amnesia, as transient global amnesia (TGA according to its acronym in English). This disorder is more common in older males and usually lasts less than twenty hours.
According to their etiologic classification, amnesia can be traumatic root (caused by damage to the head and usually transient), dissociative (associated with a long-term repressed memory), lacunar (caused by a specific event), infant (inability to remember events from childhood), global (total memory loss), post-hipnotica (when events are forgotten during hypnosis)psychogenic (for psychological cause) or source (it is possible to remember certain information but not where it was obtained).
It also speaks of Korsakoff's syndrome (a type of amnesia caused by alcoholism), the State of flight (also defined as dissociative Fugue, which appears for the psychological trauma and is usually temporary) and syndrome of mistrust in the memory (where the person is unable to trust their own memory).
The main causes of amnesia are aging, cranial injuries, Alzheimer's disease, ingestion in excess of alcohol, drugs, epilepsy treatment, vitamin deficit, malnutrition, disease of hypo or hyperthyroidism and abuse of high doses of steroids.
His appearance usually occurs from the 30 years through episodes of mind blank or repetition of automatic actions (by stress, anxiety, anguish, and depression). From the 60 arise disorders of oblivion that are associated with age ("Oblivion senile benign"), slight alterations of memory, difficulty learning and remembering names, among other things.
To find out if a person suffers from amnesia just analyze your symptoms: inability to recall events that happened recently, a few days ago or even in distant times as children. The first thing experts do when they encounter a patient who suffers from amnesia is testing to find out if there is some kind of condition in the brain, if the person has previously consumed alcohol or drugs as anxiolytics.
The immense network of circuits that the nervous system is so complex that even in many ways remains an area of absolute mysteries for scientists and any damage incurred in it can alter its normal operation forever. This happens with Alzheimer's disease, there are many people who suffer from and since it investigates and is looking for ways to cure it or reduce its consequences, however, continues to be unknown territory filled with uncertainty for specialists.
According to the Doctor of Psychiatry Joaquín Fuster, who conducted a study on the mechanisms of memory and disorders in their performance, the formation of protein plaques in the brain interferes in interneuronal communication what leads to degeneration of neurons that blocks the transmission of impulses and causes the loss of recent memory. He added that this type of disorder are developed by a genetic predisposition for what the progress in the research on the human genome (allows identifies genes involved in the development of certain diseases) could help a future diseases such as amnesia, Alzheimer's and Parkinson's to disappear forever.
In the case of amnesia for psychological reasons, they receive the name of dissociative disorders. They consist of a psychological mechanism through which the memories are inhibited knowledge if they are linked to very stressful experiences, such as accidents or psychological trauma experienced in childhood.
There are several such amnesias: dissociative amnesia (located: not can recall facts of a given period, widespread: is does not remember anything of what happened in the continuous life: inability to remember events preceding or following a systematic and precise stage: memory leak in certain aspects of the information), leak disociativa(a causa de una confusión en torno a la identidad el paciente huye de su hogar o lugar de trabajo sin ser consciente de que lo está) doing; subsequently are not able to remember what they did in that State) and dissociative identity disorder (individuals that alternate between two or more identities because of episodes of amnesia. Its causes are unacceptable stress, abnormal development before become a vision of the self and of others or a lack of protection in children), among others.
Finally, note that amnesia is a very subject in works of fiction, as in the film Memento.