Memory
Receiving new information does not guarantee its recall, learning process is
selective, some experience become part of memory .
There are three types of memory ;
1-Sensory memory ;last for brief time depends on process of
perception and represent the original stimulus accurately, visual
immediate memory for stimuli that have just been perceived
rehearsal .
2-short term memory ;it s the process by which we can memorize by
repetition like rehearsing new telephone number, short term memory
can hold only a limited amount of information .
3-Iong term memory it keeps the information .
Types of sensory memory ;
1-Iconic memory (image)-visual sensory memory –partial report
procedure .
2-Echoic memory =auditory comprehending many sounds-like hearing
the word and explains it at the end of the word .
. Chunking ; encoding of information –for example image stored in
iconic memory is as (the whole image ) or as in sounds after
interpretation,
. This is the process by which the sensory information moves to short
term memory or is to use the already stored information in the long
term memory and moves them to short term memory .
Short term memory ;
. Is often called working memory include new and old information
include visual ,auditory, somatosensory , gustatory , olfactory , even
movements which is important for remembering and thinking .
. Association – visual, or other sensory stimulus will help in process of
remembering .
. Decay ; it is the process of diminishing the stored information in
short term memory before moving it to long term memory because of
lack of rehearsal or inadequate association .
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. Proactive inhibition it is the process by which previously learned data
will act forward in time like giving 2 list of names one after the other
and the person may remember names from first list instead of second
causing confusion .
. Retrieval ; is the process by which the data become poorer in
retaining data from short term memory on successive trials but
improve on changing the model and start again .
. Displacement ; interfere with the retention of information in short
term memory, some of the old information get pushed out .
. Transfer of information from stm to itm .
. By consolidation theory ; stm is retained by short lived neural activity
where itm require structural changes in circuits of neuron –making
solid .
Long term memory ;
.Long term memory retains information that is encoded in sensory
characters also information related to previously learned –meaning .
. Factors effecting memory .
. Damage to particular parts of the brain can permanently impair the
ability to form new long term memories like for example .
1-alcohol addiction
2-sever malnutrition
3-stroke
4-head trauma
5-surgery
. Anterograde amnesia ;where the memory loss for events that occur
after the brain damage like alcoholism.
. Retrograde amnesia ;memory loss for the events occur before brain
damage like dementia where the cortical atrophy is responsible for
the cognitive dysfunction mostly shown asdefect in stm and sensory .
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Factors affecting memory
. Memory ability does change with age. Aging changes the brain and
therefore memory ability .
This is normal (provided there are no underlying medical conditions)and is
referred to as "age- related "memory change .Let s look at som of the factors
that can further affect memory change;
For the Better;
. Staying active ( mentally and physically ) seems to be the key to stabilizing
memory change with age .here are just a few " active" factors that can
positively affect memory change ; (physical activity )exercise ;
(mental activity ) educational experiences , reading , crosswords, ect ;(social
activity ) new experiences ; (healthy diet ) lower fat and lower cholesterol ).
Now let s look at some of the factors that can further affect memory change .
For the worse
A person s medical condition seems to be the primary factor affecting
memory change . Here are just a few medical factors that can negatively affect
memory change; (medical disorders and diseases ) thyroid problems, heart
problems, stroke ;(emotional problems )depression, anxiety ;(medication )
Some anti-depressants, some anti- histamines, anti – anxiety and high blood
pressure medications ;(medical changes ) menopause and other hormonal
Changes ;(poor diet ) high fat , too high cholesterol, too low cholesterol .
Dementia symptoms ;
Symptoms of dementia vary considerably by the individual and the underlying
cause of the dementia .Most people affected by dementia have some (but not
all ) of these symptoms . The symptoms may be very obvious ,or they may be
very subtle and go unrecognized for some time .The first sign of dementia is
usually loss of short- term memory .The person repeats what he just said or
forgets where she put an object just a few minutes ago. Other symptoms and
signs are as follows ;
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1-Early symptoms
-Word finding difficulty _ may be compensate using synonayms or defining
the word .
-Forgetting names, appointments , or whether or not the person has done
semething ,losing things.
-Difficulty performing familiar tasks-Driving ,cooking a meal ,household
chores, managing personal finances .
-Personality changes (for example ,sociable person becomes withdrawn or
a quiet is coarse and silly).
-Uncharacteristic behavior.
-Mood swings, often with brief periods of anger or rage
-Poor judgment .
-Behavior disorders- Paranoia and suspiciousness.
-Decline in level of functioning but able to follow established routine at
home.
-Confusion , disorientation in unfamiliar places .
2-Moderate stage of dementia;
. Worsening of symptoms seen in early dementia, with less ability to
compensate .
. Unable to carry out activities of activities of daily living (eg, bathing
,dressing ,grooming ,feeding ,using the toilet )without help.
. Disrupted sleep often napping in the daytime, up at night.
. Unable to learn new information .
. Increasing disorientation and confusion even in familiar surrounding .
. Greater risk of falls of falls and accidents due to poor judgment and
confusion .
. Behavior disorders –Paranoids, aggressiveness, agitation ,inappropriate
sexual behavior.
. Hallucinations.
. Confabulation (believing the person has done or experienced things that
never happened ).
. Inattention, poor concentration, loss of interest in the outside world .
. Abnormal moods (depression ,anxiety ).
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3-Sever stage of dementia ;
. Worsening of symptoms seen in early and intermediate dementia .
. Complete dependence on others for activities of daily living .
. May be unable to walk or move from place to place unassisted .
. Impairment of other movements such as swallowing –Increases risk of
malnutrition ,choking ,and aspiration ( inhaling foods and beverages
,saliva, or mucus into lung ).
. Complete loss of short –and long –term memory –May be unable to
recognize even close relatives and friends .
. Complications start to occur, dehydaration, bed sore, fractures .
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