Chapter 5: STM and WM Flashcards
Why do we need memory?
Because without memory there is no system for preserving and transferring information in long term. We would have no sense of the past or future
What are the three broad types of memory?
Sensory Memory
Short-term Memory
Long- term Memory
What is our Sensory Memory and how long can it hold information for?
This is holding information for a fraction of a second
(image or sound)
Example: remembering someones face after a lightening strike
What is our Short Term Memory? How long can it hold information for? How many items can it hold?
Holding information for a few seconds
(~4-7 items for 15-20 seconds)
Example: looking up a number and then dialling it
What is our Long Term Memory? How long and how much information can it store?
Storing information for long term
large data, unlimited time
What are the three kinds of long term memory?
Episodic
Procedural
Semantic
What Is the Modal Model of memory
flow diagram for memory
- input to sensory memory
- need attention to go from sensory to STM
- need rehearsal to go from STM to LTM
- retrieval to go from LTM to STM
What are control processes for memory? 2 Examples
The dynamic process controlled by a person
- attention
- rehearsal
Explain why the trail of a sparkler looks continuous ? What memory does this?
because the visual system retains perception for a fraction of a second even after it has passed (the persistence of vision)
SENSORY MEMORY
What is the persistence of vision
the retention of the continued perception of a visual stimulus even after It is no longer present
What are two examples of sensory memory from vision
- watching a movie in a theatre (still images are flashed sequentially and are perceived as continuous)
- sparkler
What is the capacity and duration of sensory memory?
Sensory memory can hold ~80% of data (12 letters) for less than a second before it is rapidly lost
(can differ based on the complexity of the stimuli)
What kinds of information does sensory memory hold?
Sensory memory can hold both visual (iconic) and auditory (echoic) memory in raw form for very brief periods
Why do we need a sensory memory?
- means of holding raw unattended information so it can be processed
- it Is how we perceive continuous motion
In sum the sensory memory hold incoming information so we can choose which ones to attend and bring to the STM
Does the sensory memory require attention?
No
Which form of memory can be called the window to the present or a mental desktop
STM
What kinds of information is stored in the STM
mostly auditory and visual
What kinds of information is stored in the LTM
any kind
STM depends on ______?
Control processes
- conscious attention, rehearsal
What is the duration of the STM
15-20 seconds or less
can be held for longer with rehearsal
How many items can be held in the STM?
7 (plus or minus 2), new studies are suggesting 4
reason why phone numbers, registration plates and SINs are 7 ish symbols
How can STM be assessed
- The digit span task
2. Change detection tasks (harder with more stimuli)
What have change detection tasks told us about how many items can be held in the STM
after change detection tasks got to 4 items, performance decreased which suggests that 4 might be the right limit of the STM
What are the two things that STM capacity is limited by
- Number of items
2. complexity of items
What is chunking?
small larger units of information can be combined to form smaller meaningful units/ chunks
123456
12 34 56
What are other ways (beside chunking) that we can use to increase STM capacity (3)
- writing/ making notes
- using figures
- external aids (calendars and reminders)
Whats an example of chunking that was not discussed in class?
waitress taking an order
What is our working memory
The system for temporary storage and manipulation of information
Three examples where we use our working memory
comprehension
learning
reasoning
Can the same information be held in the STM and WM
yes, it is based on how we are using it
- working memory is a more dynamic view of how memory systems work
What are the three components of the working memory model
Phonological loop
Visuospatial sketchpad
central executive
What is the Phonological Loop, what kind of information does it store? What is the Articulatory Rehearsal Process?
auditory/verbal information
- phonological store: holds auditory/ verbal information
- articulatory rehearsal process : enables rehearsal that prevents decay of the information from the phonological store
What is the Visuospatial Sketch Pad?
holds visual and spatial information
- holding a picture in mind or solving a puzzle
What is the Central Executive
this links to and coordinates activity of both phonological loops and the VSSP
- pulls information from the LTM when required
- Decides how to divide attention between different tasks
Explain the components of working memory when driving
- phonological loop: listening to driving directions when driving
- VSSP: visualize the map of the street
- the central executive coordinates between the PL and VSSP, and helps to ignore irrelevant information (example: the radio)
Confusing letters and words based on sound rather than visual similarity is evidence for which component of thr working memory?
Phonological loop
Evidence suggests that the phonological loop Is limited to holding ____ for _____
- Auditory/ verbal information
2. For short periods of time
What is the evidence of the VS sketch pad
- vs sketch pad holds visual and spatial images in the mind (Example: A and B are not the same)
- mentally rotating objects takes time and concentration
What is the evidence for the central executive
- control centre of the WM
- does not store information but coordinates the functions between the PL and VSSP
- primarily controls attentions
- involves the frontal lobes
What is Executive attention and which component of working memory controls it
- directing attention based on goals/interests
example- slipping on ice while driving
CENTRAL EXECUTIVE
What is Preservation? What area of our WM is this associated with
this occurs when old rules continue to be followed despite negative feedback
- Central executive deficit
(also seen in patients with schizophrenia)
What is an episodic buffer
the episodic buffer enables the wm to access information from the LTM
- enables chunking (meaningful representation of information)
What are the limitations of the Working Memory model (4)
- the central executive is difficult to test
- lack of evidence for the existence of the episodic buffer
- difficult to distinguish WM from attentional processes/attentional control
- many confusing terms
WM tasks always measure _____ _______ not just ________.
WM tasks always measure INFORMATION PROCESSING not just STORAGE.
What is the simplest test of WM
digit span test
What is the Trail Making Test
- developed during WW-II (army test battery)
- tests shifting between well-learned sets and speed of processing
(circles with numbers and letters, connect A-1, B-2 etc ) - very sensitive to WM deficits
What is Working Memory primarily associated with in the brain
prefrontal cortex
How do we test the function of the WM including holding memory “online”
Delayed response task
what is the delayed response task 1 ? damage to where results in impairment
- monkeys showed 2 trays, one with food, trays get covered, they must remember which tray had food in order to get the food
- FL
Working memory is associated with which region of the brain
PFC
Is working memory a localized function ?
no
