Learning, Memory and Amnesia

Memory and learning
are so closely connected that people often confuse them with each other. But the specialists who study them consider them two distinct phenomena.
These specialists define learning as a process that will modify a subsequent behavior.

Memory, on the other hand, is the ability to remember past experiences.

You learn a new language by studying it, but you then speak it by using your memory to retrieve the words that you have learned. Memory is essential to all learning, because it lets you store and retrieve the information that you learn. Memory is basically nothing more than the record left by a learning process. Thus, memory depends on learning. But learning also depends on memory, because the knowledge stored in your memory provides the framework to which you link new knowledge, by association. And the more extensive your framework of existing knowledge, the more easily you can link new knowledge to it.

Memory system is divided into three functions for storage

• Sensory Memory: The sensory memory retains an exact copy of what is seen or heard (visual and auditory). It only lasts for a few seconds, while some theorize it last only 300 milliseconds. It has unlimited capacity.
• Short-Term Memory (STM) - Selective attention determines what information moves from sensory memory to short-term memory. STM is most often stored as sounds, especially in recalling words, but may be stored as images. It works basically the same as a computer's RAM (Random Access Memory) in that it provides a working space for short computations and then transfers it to other parts of the memory system or discards it. It is thought to be about seven bits in length, that is, we normally remember seven items. STM is vulnerable to interruption or interference.
• Long-Term Memory - This is relatively permanent storage. Information is stored on the basis of meaning and importance.

Amnesia
is a profound memory loss which is usually caused either by physical injury to the brain or by the ingestion of a toxic substance which affects the brain. In addition, the memory loss can be caused by a traumatic, emotional event.

People with amnesia have difficulty learning new information, and/or they have difficulty recalling previously learned information. They may be disoriented and confused. Their memory deficit causes problems for them either at work, in school, or in social settings. Sometimes the memory loss is severe enough to necessitate a supervised living situation.

Psychotherapy can be helpful for people whose amnesia is caused by emotional trauma. For instance, hypnosis may help some patients/clients recall forgotten memories.

Sometimes it is appropriate to administer a drug called Amytal (sodium amobarbital) to people suffering from amnesia. The medicine helps some people recall their lost memories.

Reference:
http://thebrain.mcgill.ca/flash/d/d_07/d_07_p/d_07_p_tra/d_07_p_tra.html
http://www.nwlink.com/~donclark/hrd/learning/memory.html
http://www.apa.org/topics/learning/index.aspx
http://www.athealth.com/Consumer/disorders/Amnesia.html