Working memory Flashcards
What are the types of short term memory?
Working memory is the small amount of information that can be held in mind and used in the execution of cognitive tasks.
Sensory memory is a very brief memory that allows people to retain impressions of sensory information after the original stimulus has ceased. It is often thought of as the first stage of memory that involves registering a tremendous amount of information about the environment, but only for a very brief period. The purpose of sensory memory is to retain information long enough for it to be recognized.
What are the types of sensory memory?
Iconic memory is subliminal (visual snapshot): stimulus for 50 milliseconds for remembering letters. You can use rows with a sound tone/stimulus to guide the person to remember a specific row.
Echoic Memory: sound of 9 letters/numbers coming from their right, left back. Evaluation of total recall or partial recall using a visual cue.
Haptic memory: Also known as tactile memory, haptic involves the very brief memory of a touch. This type of sensory memory lasts for approximately two seconds.
Model for memory
Model for memory: Input - perception bottom up -> sensory memory - attention → working memory - rehearsal loop → long term memory
What are some characteristics for working memory?
Most of the information kept in short-term memory will be stored for approximately 20 to 30 seconds, or even less. Can store about 5 +- 2 items in WM.
The information in short-term memory is also highly susceptible to interference. Any new information that enters short-term memory will quickly displace old information. Similar items in the environment can also interfere with short-term memories.
Info is either forgotten or transferred to LTM.
Give an example of chunking
Chunking: e.g. a bunch of numbers (16 numbers), you put them into different significant dates that are familiar to you so that you can remember them.
Chunking information in WM frees capacity to hold other, not chunked information.
Chunking benefit is independent of the chunk size.
What are the theories of forgetting in WM?
Forgetting Information
Decay theory: the passing of time.
Interference theory: entrance of new information disrupts so this new information could replace the old information.
Give example of experiment to test forgetting theories for WM.
Probe-digit procedure: you hear a probe as a signal to recall the following numbers (numbers are presented sequentially). Variation of the speed of the presentation of the numbers.
-decay theory: worse at recalling in the slow presentation.
-interference theory: the chances should be the same for both slow and fast presentations.
Conclusion of the experiment: significant effect of the number of interfering items.
Reality: both theories matter because they both prevent the maintenance of the information to be retained.
What is the serial effect theory?
Theory: what people recall is the peak moment and the end of the experience.
Serial position effects:
Primacy effect: better recall of items in the start. Reflects the role of long term memory after having time to rehearse.
Recency effect: better recall of the items present at the end. Reflects the role of working memory.
But could also be an attentional trick with saliency instead?
What are two experiments to test the serial effect theory?
Experiment: you always remember the first and last things no matter the number of items in the list (10 vs 20 vs 30 items).
Experiment: 15 items to memorize (list of words) in 3 conditions:
Immediate recall
10 secs of backward counting
30 secs of backward counting.
Results: counting backwards does not affect the primacy effect, but it eliminates the recency effect. → first items from the list are already in LTM whereas last items were still in WM.
Experiment: Manipulation of word presentation speed (3,6,9 secs).
Seeing an item every 3 seconds led to a lower primacy effect than seeing an item every 6 or 9 seconds. The faster the items are presented, the less time we have to develop strategies to remember them.
Describe Baddeley’s WM model.
Includes visuo-spatial sketchpad, phonological loop and episodic buffer.
Central executive ← episodic buffers ← visuo-spatial sketchpad and phonological loop
What is the main characteristic of Baddeley’s WM model and give an example?
Limited capacity of the systems. Fairly independent, so tasks can be performed in parallel if they use different parts of the WM model. But same component tasks cannot be performed in parallel. Chess players experiment. Several conditions related to the different components of the WM model. Shows that for “phonological loop”, the articulatory suppression condition is the only one where performance is higher because chess does not use this component (rather it uses visuo-spatial sketchpad and central executive).
Describe the visuospatial-sketchpad
The visuo-spatial sketchpad: temporary stores and manipulates visuospatial information. Visual cache (color and shape) and internal scribe (movement and space). Do they have separate processing?
Memory tasks: visual task (chinese ideographs) vs spatial task (dot locations)
Interference tasks: color vs movement discrimination tasks.
Describe the phonological loop
Phonological store: speech perception
Articulatory control processes: speech production and rehearsal.
Phonologically similar words in a list are easier to recall. Recall is worse when words are phonologically similar?
Word-length effect: memory is usually lower for words taking a long time to say.
But possible confound: orthographic neighborhood.
What is the role of the central executive?
Central executive: involved in almost all complex cognitive processes.
Inhibition: suppressing the most dominant reflect task (e.g. stroop task)
Shifting: flexibility switching between tasks
Updating: monitoring to add or delete content.
Underpinned by frontal lobe functioning
Describe the results of Blain’s study on central executive.
Performing executive task/ physical overtraining for hours decreases MFG acitivty and increases choice impulsivity/immediacy bias.
