Transcript Introduction to Psychology

Why we forget
The 7 causes of memory
failure
The importance of forgetting
 At this point in the unit, you know the three types,
processes, and stages of memory. Now, let’s move
on to an equally important topic: forgetting.
 “Forgetting is as important as remembering. If we
remembered everything, we should be as ill off as if
we remembered nothing. It would take as long for
us to recall a space of time as it took the original
time to elapse, and we should never get ahead with
our thinking.” –William James
The dynamics of forgetting
 Forgetting can
occur at any
memory stage
 As we process
information,
we filter, alter,
or lose much of
it
Reason #1: Encoding failure

Information never enters long-term memory; not paying
attention to details produces encoding failure (bigger problem as
you get older)
Attention
External
events
Short- Encoding
Sensory
term
memory Encoding
memory
Encoding
failure leads
to forgetting
Longterm
memory
Remember the penny activity?
 Which penny is
the real thing?
Do you know
now? Probably
not.
Reason #2: Storage decay

Percentage of
list retained 60
50
when
relearning
40
30
20
10
0
12345 10
15
20
25
30
Time in days since learning list
Physical fading
away of a memory
trace over time
when it is not used:
“use it or lose it”
Reason #3: Retrieval failure

Forgetting can result from failure to retrieve information from long-term memory
Attention
External
events
Sensory
memory
Encoding
Encoding
Short-term
Long-term
memory
Retrieval memory
Retrieval failure
leads to forgetting
Reason #4: Interference
 Learning some items may disrupt retrieval of
other information
Proactive interference:
Retroactive interference:
The two directions of interference
Limiting retroactive interference: a tip
 The hour before bed is a good time to memorize new
material!
Percentage 90%
of syllables 80
recalled 70
Without interfering
events, recall is
better
After sleep
60
50
40
30
20
1
10
0
After remaining awake
2
3
4
5
6
7
Hours elapsed after learning syllables
8
Reason #5: Motivations for
Forgetting
 Motivated Forgetting
 Repression
Reason #6: Memory Construction

Memories are not files retrieved from a hard drive; they are
actively and imperfectly constructed every time you retrieve
them from a vast network of associations

We filter information and fill in missing pieces, often leading
to distortions;

Retrieval of memories is subject to bias and suggestibility;
imagination inflation

Misinformation Effect

Source Amnesia
Reason #7: Memory Disorders
 Age-associated memory impairment:
 Prospagnosia:
 Post-concussion syndrome:
 Alzheimer’s Disease: degenerative condition of the brain;
affects 4 million Americans today
 Other strange stories related to #6 and #7 to come…