Memory

The term ‘memory” denotes a specific brain function of storing and
retrieving of informations related to experiences. The duration of memory
varies from few seconds or hours, to several years.

Types of memory

Sensory memory

It means the ability to retain sensory signals in the sensory areas of the brain for a short interval of time following the actual sensory experience. This is the initial stage of memory process.

Primary memory

It is the memory of facts, words, numbers, letters or other information. The information in this memory is instantaneously made available so that a person need not search through his or her mind for it.

Secondary memory

It is the storage in the brain of information that can be recalled at some later time(hours, days, months or years later). This is also called long-term memory, fixed memory or permanent memory.

Physiology of memory

Certain anatomical, physical or chemical changes occur in the pre synaptic terminals (a part in the neuron) or perhaps in whole neurons that permanently facilitate the transmission of impulses at the synapses.

All the synapses (nerves junctions) are thus facilitated in a thought
circuit. This circuit can be re-excited by any one of many diverse signals at
later dates thereby causing memory. The overall facilitated circuit is called a memory engram or a memory trace.

Amnesia

Amnesia means memory loss. It is the inability to recall memories from the past.