Memory refers to the psychological processes of acquiring, storing, retaining, and later retrieving information. There are three major processes involved in memory: encoding, storage, and retrieval. Human memory involves the ability to both preserve and recover information. However, this is not a flawless process.

1. Memory

2. Memory
• Memory is today defined in psychology as the
faculty of encoding, storing, and retrieving
information (Squire, 2009).

3. Memory Processes
• Encoding--transforming information into a form
that can be entered and retained in the the memory
system
• Storage--retaining information in memory so that it
can be used at a later time
• Retrieval--recovering information stored in memory
so that we are consciously aware of it

4. Memory
• Psychologists have found that memory includes
three important categories:
• Sensory memory
• short-term memory
• long-term memory

5. Three Stages of Memory
• Three memory stores that differ in function,
capacity and duration
Long-term
memory
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention
Encoding
Retrieval
Maintenance Rehearsal

6. Sensory Memory
• Function —process for basic physical
characteristics
• Capacity—large
• can hold many items at once
• Duration—very brief retention of images
• .3 sec for visual info
• 2 sec for auditory info
• Divided into two types:
• iconic memory–visual information
• echoic memory– auditory information
• Attention is needed to transfer information
to working memory
Sensory
Input Sensory
Memory

7. Sensory Memory
• Visual sensory memory—brief memory of an image
or icon. Also called iconic memory.
• Auditory sensory memory—brief memory of a
sound or echo. Also called echoic memory.
• Auditory sensory memories may last a bit longer than
visual sensory memories

8. Short Term or Working Memory
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention

9. Short-Term Memory
• Function—conscious processing of information
• where information is actively worked on
• Capacity—limited (holds 7+/-2 items)
• Duration—brief storage (about 30 seconds)
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention

10. Maintenance Rehearsal
• Mental or verbal repetition of information allows
information to remain in working memory longer than
the usual 30 seconds
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention
Maintenance Rehearsal

11. Long-Term Memory
• Once information passes from sensory to
working memory, it can be encoded into
long-term memory
Long-term
memory
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention
Encoding
Retrieval
Maintenance Rehearsal

12. Long-Term Memory
• Function—organizes and stores information
• more passive form of storage than working memory
• Unlimited capacity
• Duration—thought by some to be permanent
Long-term
memory
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention
Encoding
Retrieval
Maintenance Rehearsal

13. Long-Term Memory
• Encoding—process that controls movement from
working to long-term memory store
• Retrieval—process that controls flow of information
from long-term to working memory store
Long-term
memory
Working or
Short-term
Memory
Sensory
Input
Sensory
Memory
Attention
Encoding
Retrieval
Maintenance Rehearsal

14. Chunking
• Grouping small bits of information
into larger units of information
• expands working memory load
• Which is easier to remember?
• 4 8 3 7 9 2 5 1 6
• 483 792 516

15. Automatic vs. Effortful Encoding
• Automatic processing
• Unconscious encoding of information
• Examples:
• What did you eat for lunch today?
• Was the last time you studied during the day or night?
• You know the meanings of these very words you are
reading. Are you actively trying to process the
definition of the words?

16. Automatic vs. Effortful Encoding
• Effortful processing
• Requires attention and conscious effort
• Examples:
• Memorizing your notes for your upcoming
Introduction to Psychology exams
• Repeating a phone number in your head until
you can write it down

17. Types of Long-Term Memory
• Explicit memory—memory with awareness;
information can be consciously recollected;
also called declarative memory
• Implicit memory—memory without
awareness; memory that affects behavior but
cannot consciously be recalled; also called
nondeclarative memory

18. Explicit Memory
• Declarative or conscious memory
• Memory consciously recalled or
declared
• Can use explicit memory to directly
respond to a question
• Two subtypes of explicit memory

19. Explicit Memory
• Episodic information—information about
events or “episodes”
• Semantic information—information about
facts, general knowledge, school work

20. Episodic Memory
• Memory tied to your own personal experiences
• Examples:
• What month is your birthday?
• Do you like to eat caramel apples?
• Q: Why are these called explicit memories?
• A: Because you can actively declare your answers to these
questions

21. Semantic Memory
• Memory not tied to personal events
• General facts and definitions about
the world
• Examples:
• How many tires on a car?
• What is a cloud?
• What color is a banana?
• Does NOT depend on tying the item to your past

22. Implicit Memory
•Nondeclarative memory
•Influences your thoughts or
behavior, but does not enter
consciousness

23. Procedural Memory
• Memory that enables you to perform specific
learned skills or habitual responses
• Examples:
• Riding a bike
• Using the shift stick while driving
• Tying your shoe laces
• Q: Why are these procedural memories implicit?
• A: Don’t have to consciously remember the steps
involved in these actions to perform them
• Try to explain to someone how to tie a shoelace

24. How are memories organized?
Clustering--organizing items into
related groups during recall from
long-term memory

25. Semantic Network Model
• Mental links between concepts
• common properties provide basis for
mental link
• Shorter path between two concepts =
stronger association in memory
• Activation of a concept starts decremental
spread of activity to nearby concepts

26. Semantic Network Model
Red
Fire
House
Cherry
Apple
Rose
Pear
Ambulance
Fire
Engine
Truck
Bus
Car
Flower
Violet
Hot
Pot
Stove
Pan
Pie

27. Measures of Retrieval
• Recall—test of LTM that involves retrieving memories
without cues, also termed free recall
• Cued recall—test of LTM that involves remembering an
item of information in response to a retrieval cue
• Recognition—test of LTM that involves identifying correct
information from a series of possible choices
• Serial position effect—tendency to remember items at the
beginning and end of a list better than items in the middle

28. Cont..
• The tendency to recall the first items in a list is called
the primacy effect
• the tendency to recall the final items in a list is called
the recency effect.

29. encoding specificity principle
• The principle that when the conditions of
information retrieval are similar to the conditions of
information encoding, retrieval is more likely to be
successful.

30. Encoding Specificity
– When conditions of retrieval are similar to conditions
of encoding, retrieval is more likely to be successful
– You are more likely to remember things if the
conditions under which you recall them are similar to
the conditions under which you learned them

31. Encoding Specificity
• Context effects—environmental cues to recall
• The tendency to recover information more easily
when the retrieval occurs in the same setting as the
original learning of the information
• State dependent retrieval—physical, internal factors
• Mood Congruence—factors related to mood or
emotions
• An encoding specificity phenomenon in which a
given mood tends to evoke memories that are
consistent with that mood.

32. Flashbulb Memories
• Recall of very specific images or details about a vivid,
rare, or significant event
• May seem very vivid and specific, but they are not
more accurate than ordinary memories
• Can you remember where you were when you heard
about the terrorist attacks on the World Trade Center
and the Pentagon?

33. Memory Distortion
• Memory can be distorted as people try
to fit new info into existing schemas
• Giving misleading information after an
event causes subjects to unknowingly
distort their memories to incorporate
the new misleading information

34. Forgetting
• The inability to recall information that was previously
available.
encoding failure
• The inability to recall specific information because of
insufficient encoding of the information for storage
in long-term memory
What causes forgetting?
• Psychologists have identified several factors that
contribute to forgetting, including encoding failure,
decay, interference, and motivated forgetting.

35. Why do we forget?
• Forgetting
can occur
at any
memory
stage
Retrieval from long-term memory
Depending on interference, retrieval
cues, moods, and motives, some
things get retrieved, some don’t
Long-term storage
Some items are altered or lost
Short-term memory
A few items are both noticed
and encoded
Sensory memory
The senses momentarily register
amazing detail

36. Forgetting as retrieval failure
• Retrieval—process of accessing stored information
• Sometimes info is encoded into LTM, but we can’t
retrieve it
Retrieval failure
leads to forgetting
Retrieval
X
Encoding
Short-term
memory
Long-term
memory

37. The Forgetting Curve
• Ebbinghaus (1885) created new material to
memorize: thousands of nonsense syllables.
• A nonsense syllable is a three-letter combination,
made up of two consonants and a vowel, such as
WIB or MEP.
• It almost sounds like a word, but it is meaningless.

38. Cont..
• Ebbinghaus carefully noted how many times he had
to repeat a list of 13 nonsense syllables before he
could recall the list perfectly.
• To give you a feeling for this task, here’s a typical list:
• ROH, LEZ, SUW, QOV, XAR, KUF, WEP, BIW,
CUL, TIX, QAP, WEJ, ZOD

39. Cont..
• Once he had learned the nonsense syllables
• Ebbinghaus tested his recall of them after varying
amounts of time, ranging from 20 minutes to 31
days.
• He plotted his results in the now-famous Ebbinghaus
forgetting curve

40. The Forgetting Curve
Hermann Ebbinghaus
first began to study
forgetting using
nonsense syllables
Nonsense syllables
are three-letter
combinations that
look like words but
are meaningless
(ROH, KUF)

41. Forgetting Theories
• Encoding failure
• Interference
theories
• Motivated
forgetting
• Decay

42. Forgetting as encoding failure
• Info never encoded into LTM
Encoding
X Long-term
memory
Encoding failure
leads to forgetting
Short-term
memory

43. Encoding Failures
Even though you’ve seen thousands
of pennies, you’ve probably never
looked at one closely to encode
specific features

44. Which is the real penny?
(a) (b) (c) (d) (e)
(f) (g) (h) (i) (j)
(k) (l) (m) (n) (o)

45. (a) (b) (c) (d) (e)
(f) (g) (h) (i) (j)
(k) (l) (m) (n) (o)
Answer

46. Interference Theories
• “Memories interfering with memories”
• Forgetting NOT caused by mere passage
of time
• Caused by one memory competing with or
replacing another memory
• Two types of interference

47. Two Types of Interference
Types of Interference
Retroactive
Interference
Proactive
Interference

48. Retroactive Interference
• When a NEW memory interferes with
remembering OLD information
• Example: When new phone number
interferes with ability to remember old
phone number

49. French 101
Mid-term
exam
Retroactive Interference
• Example: Learning a new language
interferes with ability to remember
old language
Study French
papier
livre plume
école
Study Spanish
papel
libro pluma
escuela
retroactive interference

50. Proactive Interference
• Opposite of retroactive
interference
• When an OLD memory
interferes with remembering
NEW information
• Example: Memories of
where you parked your car
on campus the past week
interferes with ability find
car today

51. Motivated Forgetting
Undesired memory is held back form awareness
• Suppression—conscious forgetting
• Repression—unconscious forgetting (Freudian)

52. Decay Theories
• Memories fade away
or decay gradually if
unused
• Time plays critical
role
• Ability to retrieve
info declines with
time after original
encoding
Average
percentage
of
information
retained
0
10
20
30
40
50
60
70
80
90
100
20
mins
1
hr
8
hrs
24
hrs
2
days
6
days
31
days
Interval between original learning
of nonsense syllables and memory
test
100%

53. Decay Theories
 Biology-based theory
 When new memory formed, it creates
a memory trace
 a change in brain structure or chemistry
 If unused, normal brain metabolic
processes erode memory trace
 Theory not widely favored today

54. Forming False Memories-
Amnesia
• Amnesia—severe memory loss
• Retrograde amnesia—inability to remember past
episodic information; common after head injury;
need for consolidation
• Anterograde amnesia—inability to form new
memories; related to hippocampus damage

55. Cont..
Dementia
• Progressive deterioration and impairment of
memory, reasoning, and other cognitive functions
occurring as the result of a disease or a condition.
Alzheimer’s disease (AD)
• A progressive disease that destroys the brain’s
neurons, gradually impairing memory, thinking,
language, and other cognitive functions, resulting in
the complete inability to care for oneself; the most
common cause of dementia