Memory

According to Cognitive Psychologist

Types of Memory

• Sensory Memory
• Short-term Memory
• Long-term Memory

1. Sensory Memory

Kind of memory which last only for mili seconds but its capacity is essentially unlimited in what may be taken.

2. Short-term Memory

Type of memory which is of limited capacity over 2-7 bits of information and degrades over a matter of seconds, if information is not transferred to a long-term memory.

3. Long-term Memory

The unlimited capacity and relatively permanent traces of memory which lasts months and years.Such ability is called long-term memory.Neuro-psychologist are more concerned with long-term memory and its disorders.

Sub-systems of Long-term Memory

1. Declarative Memory

A form of memory that is explicit verbalize and excess-able to conscious awareness.This term comes from declare which means to proclaim to announce.

Sub Types

I. Semantic Memory

It is generalized memory such as knowing the meaning of word with knowing where or when you learned that words.

II. Episodic Memory

Episodic memory is autobiographical memory that pertain to a person's particular history.When we recall specific episodes or relate an event to a particular time and place.


Research has implicated 3 major structures which are involved in declarative memory.

I. The 1st center around the Medial Temporal Lobe

This center is mostly consisted on the hypo-campus and medial temporal lobe.Neuro-psychologist believed periphinal and para-hypo-campus cortex's adjacent to hypocampal formation have a deep role in memory.

II. The 2nd center which is around the Diencephala

the structure of diencephla involved in memory centered around specific nuclei of the thalamus and mamillary bodies of the hypothalamus.This thalamus consist of several nuclei which the dorsal medial nucleus of the thalamus which is often implicated and korsa koffa syndrome and in some case of amnesia.

III. The Basal fore-brain

The basal fore-brain is a sub cortical part of the talencephala surrounding the inferior tips of the frontal horns and is interconnected with limbic structure, a part of limbic system. Expert suggest that extensive damage of basal fore-brain affected the memory.Another system of declarative memory is called paps circuit which is an anatomic circuit central around the hypo-campus plays a deep role in the declarative memory processing.

2. Procedural Memory

Non declarative memory include instances of perceptual stimulus response and motor learning that are not necessarily conscious or the memory demonstrated by means where by conscious awareness is not always necessarily such as skill learning and conditioning. Non declarative memory appears operate automatically.

Sub Types

I. Skill Learning

In this type subjects perform a challenging task on repeated trails in one or more.

II. Priming/Repeation

Priming is also called repeation.Priming refers to the fact that when people perceive a particular stimulus.It becomes easier for them to perceive again.

III. Conditioning

Very simple it means salivation when you see a favorite food.


1. Temporal Lobe

Researchers suggest that the temporal cortex makes a significant contribution in the memory.Due to impairment of these hemispheres memory function may become disturb e.g Right temporal lobe removal patients are impaired on face recognition, spatial position and maze learning test. Left temporal lesion functional impairment can create disturbances in the recall of word's list, recall of constant diagrams, non spatial association, regulation of non sense figure, tunes and previously seen photographs.
Due to cortical cortex injuries in partial posterior or temporal lobe and occipital lobe produce long-term memory difficulties e.g color amnesia, phase amnesia, prosopagnosia, object amnesia, topographically amnesia (Inability to recall the location of the environment).Damage of cortex can calls Alzheimer's desease.

2. Amygdala

This part is composed of number of separate nuclei.Each has its specific functions and are associated emotional events.It is much involved in memory.

• The medial nucleus
• The lateral
• The central nucleus
• The basal nucleus
• The medial nucleus is consisted on several sub nuclei that receive sensory inputs.

3. Hipocampus

Studies indicate that the damages in hypo-campus can create spatial memory e.g field difficulty of remembering ability.

4. The Periphinal Cortex

The damage to the periphinal the most lateral position of the medial temporal lobe caused visual tasks or recognition memory defects.

5. The Basal Fore-brain

The area just anterior to the hypothalamus in which polynergic fibers lie.The polynergic fibers projects to all cortical areas and provided up-to 70 percent of polynergic synapse in these areas.These cells are actively involved in memory functions.Impairments in this area creates some kind of amnesia.