Memory
May 21st, 2008Memory is the ability of human beings and other organism to register and store information based on experience and retrieve it whenever required. Memory and techniques to improve memory are studied both in neuroscience and cognitive psychology.
The 3 main stages in the formation and retrieval of memory are registration - the processing of received information, creating a permanent record of the information received and recalling or retrieval of the information whenever required.
Based on the duration for which memory is retained, it is classified as:
1. Sensory memory: is the memory of an item immediately after it is perceived. After an object is seen for the first time, a person remembers it for a very short duration of time, an average of 350 milliseconds. This memory has a limited capacity.
2. Short term memory: some of the items from sensory memory are then transferred to short term memory. The duration of short term memory varies between a few seconds to up to a minute. Short term memory also has a limited capacity and can be used to store 4-5 items at a time. By splitting information into meaningful chunks, short term memory can be improved.
3. Long term memory is stored for a much longer time, usually for the lifetime of the individual. It is stored on the basis of semantics and is due to the permanent changes in the neural connections in the brain. It is believed that sleep improves the storage of information required for long term memory.