MEMORY

Dr Ravi Soni

Encoding and storage of LTM

Encoding for the long term storage requires special attention or strategies of some sort; just being exposed to something is usually not sufficient for long term memory storage.

I. Role of OrganizationII. Role of ImageryIII. Role of Constructive Process

Role of Organization• Is to organize or arrange, the input so that it fits into existing long term

memory categories, is grouped in some logical manner, or is arranged in some another way that makes sense

• Organizational encoding is of two types:I. Inherent in the input itself (Inherent organization)II. That added by person during encoding (subjective organization) With the help of Organization, learning becomes rapid and memory is

good. Memory of words arranged in logical hierarchies: inherent Grouping and pairing of the words: Subjective

Role of Imagery• Incoming information is stored by forming the image of it• IMAGES: are partial and altered representation of what is in the world

around us• The words for which visual images were easily formed were called

CONCRETE• The words which evoke very little visual imagery is called ABSTRACT• Bottle: Concrete word for which we can easily form an image• Truth/Mercy are the words which evoke very little visual imagery• Significance is that: If an item evokes imagery (concrete words) it evokes

good recall

Role of Constructive Process• During encoding, the to be remembered information, especially if it is a

complex life event or something you have read, is modified.• Certain details may be accentuated, the material may be simplified• It is not a literal copy of the input- changed in many other ways during

encoding and storage• One important constructive process is encoding only the ‘MEANING’ of

the complex information• Use of ‘INFERENCE’ in the constructive process-tend to remember what

was inferred at the time of encoding and storage

Retrieval• Information is encoded and stored in LTM, but it must be retrieved, if it is

to be usedI. Retrieval cuesII. Reconstructive process1. RETRIEVAL CUES: are clues or reminders which direct memory search to

the appropriate part of the LTM library• Retrieval is good when conditions favor rich and elaborate encoding

because it provides readily available retrieval cues• While learning we provide our own retrieval cues-subjective

organization. This is a trick in having good memory.

Retrieval STATE DEPENDENT MEMORY: Influence of the situation that affect the

retrieval of LTM Particular emotional/drugged state Alcoholic intoxication2. RECONSTRUCTIVE PROCESS: modification of the already stored input Reconstruction is sometimes called ‘confabulation’

Forgetting• Apparent loss of information already encoded and stored in LTM• Much of what we think we have forgotten does not really qualify as

‘forgotten’ because it was never encoded and stored.• Information processing theory• Level of processing theoryWhy we forget?1. Interference problem2. Retrieval problem3. Motivated forgetting

Interference• Learning new things interfere with our memory of what we have learned

earlier (Retroactive interference) and prior learning interferes with our memories of things learned later (Proactive interference)

• Example: A information(initially learned), B Information(later learned)• If B interferes retrieval of the A-Retroactive interference• If A interferes retrieval of the B-Proactive interferenceWhy interference causes problems?a. Breaks association between stimuli and responses formed during

learningb. Effect on the memory of retrieval cues

Retrieval Problems• We often cannot recall something while actively searching for it, we may

later recall the information when we have given up the search and are doing something else.

• New activity may give another set of appropriate reminders or cues and make us search through portions of our LTM store not examined before.

Why it happens?a. Reconstructive process tend to distort our recallb. State dependent memory (emotional factors)c. Motivated forgetting

Motivated Forgetting• Based on SIGMUND FREUD’S Psychoanalysis and Repression• REPRESSION: refers to tendency of the people to have difficulty in retrieval of

anxiety provoking or threatening information, and what is associated with that information, from LTM.

• Example: I may forgot the names of the people I do not like.• Forgetting conversation with the man you don’t like.• Retrieval of this kind of information is possible under special circumstances.• FREE ASSOCIATION- asking an individual to say whatever comes to mind.

During free association retrieval cues for repressed memories are generated• Hypnosis and drugs: TRUTH SERUM

Amnesias• Amnesia is profound memory deficit either due to loss of

what has been stored or to the inability to form new memories

• Amnesias are of two types:I. PSYCHOLOGICAL AMNESIAS II. BIOLOGICAL AMNESIAS

Psychological Amnesias• Result from major disturbances in the process of encoding,

storage and retrieval without any known brain malfunction.• Three types:1. Childhood Amnesia2. Dream Amnesia3. Defensive Amnesia

Childhood Amnesia• We forget our early childhood memoryWhy?I. Repression: because they are associated with forbidden, guilt arousing

sexual and aggressive memoriesII. Young children encode and store memory as IMAGES or FEELINGS. In

adult life our language dominated memories do not have retrieval cues appropriate for gaining access to the stored memory of childhood

III. Brain is immature during early childhood, so it can not store LTMs until its maturation becomes complete. Language ability and memory develop together

Dream Amnesia• We usually forget our dreamsWhy?I. Freud said that the dream is expression of forbidden sexual and

aggressive urges which can produce strong guilt and anxiety if we become aware of it

II. Differences in the symbol system used in dreaming and waking state similar to childhood amnesia

III. Dreaming brain seems to be in a special state different from that of the waking brain

Defensive Amnesia• People with this form of amnesia may forget their names, where they have come

from, who their spouses are and many other important details of their past lives• It is called defensive because it is usually considered to be a way of protecting

oneself from the guilt or anxiety that can result from intense, intolerable life situations and conflicts

• Extreme form of REPRESSION• May last for weeks, months or years• When amnesia returns person regains all the lost memory but there is amnesia for

the events occurred during amnestic episode.Why?I. Memories for the amnestic period are repressedII. Retrieval cues are lacking

Biological Amnesias• Concussions from the blows to the head, other damage to the

brain, temporary disturbances in the brain’s blood supply, certain drugs and brain diseases

• Three types:1. Transient Global Amnesia2. Marijuana, Alcohol, and Amnesia3. Diseases of the brain

Transient Global Amnesia• Profound memory problem without loss of consciousness• Sudden, without obvious cause• May last for only few hours or days• Global Amnesia because both RETROGRADE and ANTROGRADE AMNESIA

is there• RETROGRADE AMNESIA: forgetting events one was exposed in the past• ANTEROGRADE AMNESIA: inability to encode and store new informationCAUSE:• Temporary alterations in the normal pattern of blood flow to the brain

Marijuana, Alcohol, and Amnesia• Marijuana has itself a limited, short lived effect on the encoding, storage

and retrieval of information• Alcohol: in a drunken state whatever patient does, he has amnesia for

that, when he becomes soberWhy?I. Disruption of encoding and storage processes due to effect of the

alcoholII. State dependent memory

Diseases of the brain• Syphilis of the brain and other infections, strokes and other permanent

disorders of the brain blood flow, brain tumors, disorders of the brain metabolism, multiple sclerosis, diseases caused by toxic chemicals, senile dementia and primary degenerative dementia

• SENILE DEMENTIA: deficits in many intellectual abilities-memory, attention, judgment and abstract thought

• Personality changes, delusions, general disorientation• Initially largely anterograde• Memories of the past experiences are not affected until late• Result from reduction in the blood flow to the brain-arteriosclerosis

Diseases of the brain• PRIMARY DEGENERATIVE AMNESIA: similar to senile

dementia• But many symptoms often begin in the middle age• Like ALZHEIMER’R DISEASE• Begins somewhat early and there is progressive mental

deterioration• Both anterograde and retrograde amnesia develops