Amnesia

Amnesia

Introduction

In medical parlance, the ' amnesia is a disorder of long-term memory episodic. The person suffering from amnesia may be unable to remember recent events of his life, or in severe cases even remote events, and may not be able to acquire new memories permanently, while it is generally preserved the ability to learn new actions.The amnesia is a disorder of the operation of the memory, during which the individual is unable to retain or retrieve previously stored information. The causes of amnesia are organic or functional. Organic causes include damage to the brain caused by disease or trauma, or use of certain drugs (usually sedative). The Functional causes are psychological factors, such as defense mechanisms. The amnesia hysterical posttraumatic is an example of this factor. The amnesia can also be spontaneous, in the case of the overall transient amnesia has the highest rate of cases in people in middle age and the elderly, particularly males, and usually lasts less than 20 hours.

Types of Amnesia

In Chronological classification: Anterograde Amnesia. The new events are not transferred to long term memory, so the sufferer will not be able to remember anything that happened after the onset of this type of amnesia for more than a brief moment. The complement to this is the retrograde amnesia. Retrograde Amnesia. Not recall events that occurred before the start of the disease. These terms are used to categorize symptoms, not to indicate a particular cause of etiology. Both categories of amnesia can occur while the patient, and is a result of damage to brain regions most closely associated with episodic memory / declarative: the medial temporal lobes and especially the hippocampus.

According to Etiologic classification

Posttraumatic amnesia. It is usually caused by head injury (fall, blow to the head) does not penetrate the skull. This mechanism is known as memory consolidation, and the same molecular changes consist of protein synthesis based on representations that are fixed in the brain. The person suffering post-traumatic amnesia may also file a coma that can last from seconds to weeks, depending on the severity of the trauma. After coma presents a period of confusion. The person will have anterograde amnesia of the events in the period of confusion. Amnesia period between brain injury responsible for memory loss and the point at which resets the memory related functions.

Dissociative Amnesia. Usually refers to a long-term repressed memory as a result of trauma either psychological or emotional.

Alcoholism can cause a type of memory loss known as Korsakoff syndrome. This is caused by brain damage due to a deficiency of vitamin B1 and its increase will be progressive if alcohol and outpatient nutritional pattern changes. Other neurological problems likely to be present in combination with this type of amnesia: sensory and motor problems, extreme confusion and personality changes. A brain structure that is associated with significant amnesia in Korsakoff syndrome is dorsomedial nuclei of the thalamus.

Amnesia lacunar. Memory loss is a specific event.

Fugue State is also known as dissociative ...