Psychology: The study of human behaviour
Overview of Memory
Memory is the cognitive process of encoding, storing, and retrieving information.
Encoding refers to the process by which stimuli are put into information that is used by
our memory system
Storage is the ability to keep certain memories
Retrieving is the ability to take from the stored memory at any given time
Retrieving information is a progressive reactivation since a lot of the memory is latent
Donald Hebb used the idea of active/latent distinction to come up with two ways that
the brain remembered information. This was called the Dual trace theory.
Hebb thought that activity was due to the constant firing of neurons creating a struc-
tural latent state even after the experience had transpired.
Richard Atkinson and Richard Shiffrin both suggested that memory takes three forms:
Short-term, sensory memory, and long-term memory.
The first two contain active traces while the last contains latent structures
Sensory memory is memory in which representations of physical features of a stimu-
lus are stored for no more than a second
Short term memory is an immediate memory for stimuli that have just been perceived.
There is a certain capacity to our short term memory. We must keep repeating things
in our heads to remember them, or store them into long term memory.
Long term memory is memory in which information is represented on a permanent or
There is no limit to our ability of long term memory since it does not need to be re-
Memory follows the Modal Model since it is widely assumed: Sensory Memory
We use afterimages of things we see in order to analyze what we just saw. We truly
see things before we understand them in a sense.
Visual sensory memory called iconic memory is a form of sensory memory that is very
closely tied to perception and allows us to hold a visual representation of what we just
perceived. This type of memory is sometimes called visual persistence.
Sperling used the whole report procedure to see how many letters people could re-
member after being flashed 9 letters. on average, people could only remember 4-5 let-
Sperling also used a partial-report procedure in which he allowed the subjects to see
the letters for a brief time then took them away and rang a bell. The subjects had to read
a row of the image they still had in their minds and they did well. However if he took
longer to ask them what letter (longer than a second), the subjects would get only 50%
The participants saw all 9 letters truly, however as they named them the image faded
Auditory sensory memory is called Echoic memory and it is a form of sensory memory
for sounds that have just been perceived.
Echoic memory holds sounds in until the complete word has been said. This is how
we may put two syllables together to form the word bottom for example. Echoic memory was thought to only last 4 seconds but ow has been discovered to last
Short-Term or Working Memory
Encoding of Information in the Short Term: Interaction with Long-Term Memory
In order to identify things such as sequences of numbers, information must be taken
out of long term memory in order for us to name the numbers in the first place.
7 x 19 = ?
In order to know what a 7 is and what a 19 is and that the x means multiply, we must
go into long term memory!
Since short term memory contains sensory memory and longterm memory, scientists
have labelled this memory working memory.
Primary and Recency Effects
When a list is called out to you, the tendency to remember the first words is called the
The tendency to remember the last words is called the recency effect.
The reason for the primary effect is that words at the beginning of a list were repeated
more in your head and therefore are remembered better. The short term memory was
stored in long term memory.
The reason for the recency effect is that the last words are still in your short term
memory and like a picture in your head you may still see them for brief seconds.
These effects are the consequence of the behaviour of memory.
The Limits of Working Memory