PSY270H1 Lecture Notes - Lecture 5: Fusiform Face Area
Memory is the process of retaining, retrieving and using information about stimuli,
events, ideas and skills after the information is no longer present. It is an integrated
system that works together (although some parts are more important or specialized for
certain types). It acquires, stores, and retrieves information. If any of these three steps do
not work properly, the entire memory system may not function. It has often been
compared to a computer but memory actually has a limited capacity, space, time and
There are certain types of memory
Transient/temporary = sensory memory, short-term/working memory.
Implicit/explicit = declarative (explicit) /non-declarative (implicit)
Episodic = event memory
The Question of Capacity
How much information can we hold at any one time (for each system)?
How long can people can hold onto it and how much do they forget?
How quickly or often does the information get lost? How do you get your memory back?
What is the purpose of memory?
It is a sort of “time traveling” machine. Memory is also important for many reasons that
we take for granted; such as recognizing objects, people, places, faces, and the like. Take
for example people that lose their memory, there are individuals who have damaged
temporal lobe (which is important for forming new memories) and can’t remember
anything past 1 or 2 minutes.
Memory is crucial for everything that we do; like remembering an unfamiliar number
temporarily (short term memory).
Hold driving directions in mind while driving (working memory (holding something in
mine while doing something else)).
What you ate for dinner yesterday, a week ago, a year ago (episodic memory (something
that happened to you, remembering yourself doing something, an actual event)).
Do you remember how you learned the 9/11 terrorist attacks? - Flashbulb memory
For simple facts (are bananas edible?) – Semantic memory
Tying shoe laces or riding a bicycle (you don’t actually think about doing these things) –
procedural/implicit memory. Holds information about things we have learned how to do
automatically and no longer have to think about.
The Modal Model of Memory
This is an outdated model but it has many of the basic principles of memory.
The stages of memory in this model are called the structural features of the model and
there are three:
(1) Sensory Memory : initial stage which holds all incoming information for a short
span of time (usually a second or less)
(2) Short-term memory (STM): If you pay attention and do something to the
information in sensory memory it goes into short-term memory. It holds 5-7 items
for 15-30 seconds.
(3) Long-term memory (LTM): If you repeat information in STM (or think about it,
etc) it goes into the LTM. Holds a large amount of information for years or
Whenever we do anything we bring information in from LTM into STM but the two still
have mechanisms that make the two distinct (and often the STM is simply considered a
stepping stone to LTM). Consider the experiment we did with word recall in class and the
recency and primacy effect.
This model of memory also includes a control processes. This is and active processes that
can be controlled by the thinker, it is task dependant and varies individual to individual.
This can include rehearsal, attention, focus, chunking, etc.
It is crucial to remember that the components of memory do not act separately.
The Sensory Memory
Retains sensory stimulation for a brief period of time (It is a temporary store) and it even
disputed at being a memory system in the first place. It holds incoming information from
the environment and stores raw and unanalyzed information (it is modality specific).
Consider the sparkler’s trail which happens because of the retention of the perception of
light (called persistence of vision).
When watching movies, the same thing happens. You see frames projected onto the
screen, one by one in fast intervals, and due to persistence of vision you see continuous
action not still frames.
This researcher challenged the concept of a limited perceptual span.
Sperling flashed an array of letters on the screen for 50 milliseconds and asked the
participants to report as many of the letters as possible. He used the whole report
method because participants were asked to report as many letters are possible. The
average amount reported was 4-5 out of 12 letters. However, participants often told
Sperling that they could see all the letters but just couldn’t remember them.
So did the participants only see 4-5 letters because of brief exposure or did they see most
of the letters but had their perception of them fade as they were reporting them.
He devised the partial report method in order to determine which of these two
possibilities were correct.
So, he flashed the words again for 50 ms but afterwards indicated with a cue which row
of letters were to be reported. In this trial participants responded with 82% correctness
rate. This proved that the problem was with the duration the information lasted in your
memory not its capacity; he therefore concluded that the latter option was much more
He devised the delayed partial report method in order to determine the time it took for
this information to fade. Here the tone cues for the row of letters were delayed. The result
was that participants were only able to remember around 1 letter out of a row or 4 out of
the entire set.
Sperling concluded that there is a short-lived sensory memory that registers most of the
information that hits our visual receptors and that this information usually decays very
quickly. This is called iconic memory or visual icon and it is equivalent to the sensory
memory discussed in the beginning.
Sounds also persist in the mind and this is called echoic memory. It lasts a few seconds
To sum up … Sperling devised a method for controlling the reporting factor in
apprehension and showed that sensory memory (iconic) has a high capacity (maybe
unlimited) but a short duration (typically 1 second). He also happened to introduce the
idea of iconic memory as a sensory store.
Sensory memory is important for (1) collecting information to be processed and (2)
holding the information briefly during initial processing and (3) filling in the blanks when
stimulation is intermittent.
Capacity is large but duration is brief.
Echoic (auditory) information seems to last a bit longer in the sensory memory.
Lasts for approximately four seconds. Research by Darwin, Turvey and Crowder
called “The 3 eared man experiment” gives us some insight into the workings of
echoic memory. This was an adaptation of Sperling’s experiment. Participants
heard letters and numbers simultaneously (these sounds came from the different
angles of the room; right, left, middle). You would have to report everything or
some of the information (whole, partial, or delayed report) after you were cued
from a selected area of the room (stimuli you heard on the right, in the middle or
from the left) This experiment replicated Sperling’s pattern of results and the
maximum number of items recalled was 5 and the echo lasted for about 2