Unit 2 Flashcards
What does Sensory memory mean?
the ability to perceive and remember extremely brief visual stimuli
How do we respond to persistent/permanent vs. transient/fleeting objects?
with the same level of adaptation and efficiency to both persistent (permanent) and transient (fleeting) objects
What happens when a sequence of static images is shown rapidly with blank intervals?
we perceive it as a continous moving image
-> perceptual system stores visual information long enough to bridge the gap between the static images, integrating each one with the next, very slightly different image
What does the iconig memory contain?
no letters or digits but patterns of light waiting to be analyzed
is visual sensory memory a unitary system?
no
Which 2 phenomena with very different properties does sensory memory include?
- visible persistance
- iconic memory
What is visual persistence?
visual stimuli remains visible for some time after their physical disappearance, but information about their characteristics also persist
What does informative persistence allows us to do?
to extract information after a short period of time in the same way that we extract it when the stimulus is physically present
What is the term sensory memory applied to?
the brief storage of information within a specific modality
What is iconic memory?
the brief storage of visual information
-> Information stores that preserve input beyond the very existence of the generating stimulus
What is echoic memory?
the brief storage of auditory information
-> Information stores that preserve input beyond the very existence of the generating stimulus
What did Sir William Hamilton (XIX century) found when a handful of balls are thrown on a flat surface?
not easy to see at a glance more than six or seven
-> estimate correct until it reached more or less eight or nine
What specific machine did James Mckeen Cattell (1883) use?
Tachistoscope
What is the technique of the total report?
asking subject to report ALL items they remember (after presenting sets of letters or words)
What were James Mckeen Cattell’s (1883) results of the total report technique after being presented with sets of letters or words?
- when stimulus contained up to four items: no mistakes
- when number increased: errors begun to appear (correct average between four and five items)
What do we call the amount of information correctly identified and remembered after a brief visual position?
apprehension amplitude
Which are the two fundamental problems in retrieving sensory motor presentation according to Sperling (1960)?
- after a brief visual presentation every observer sees more information than they can say next
- observer’s report contains only the information recalled, not all that he has seen
What are Sperling’s (1960) 2 reasons for the subjects insistence that one sees more than is remembered?
- A limitation of memory
- Subjects have more information available about the stimulus presented than they can provide
What did Sperling (1960) confirm about the average apprehension amplitude of the subjects in a total reporting task?
was around 4.5 letters
-> memory problem, NOT perception problem
What is a partial report task?
participants have to report only part of presented stimulus
What were the results of Sperling’s Partial report task?
depending on the delay condition:
- 0ms: average of 9.1 letters (76%) remembered, twice as large as the immediate memory aplitude 4.5 letters
- 500ms: average of 9.1 letters (76%)
- 600ms: average of 4.6 letters (38%)
Sperlin - Partial report task - Conclusions
What is the main function of sensory memory stores according to Ruiz-Vargas (1980)?
To extend the life of stimuli beyond the duration of the physical stimulus.
Sperlin - Partial report task - Conclusions
How long does visual information remain available in sensory memory?
Around 500 ms for visual mode, with the amount decaying as a function of signal delay.
Sperlin - Partial report task - Conclusions
What proves the existence of iconic memory?
The decrease in subject performance as a function of signal delay.
Sperlin - Partial report task - Conclusions
What is the “superiority of the partial report”?
the discrepancy between partial and total report values, indicating the involvement of two different memory systems.
Sperlin - Partial report task - Conclusions
What are the two different memory systems of the superiority of the partial report?
- iconic memory
- short-term memory
What does iconic memory have?
high-capacity and very short-lived system
What is short-term memory?
a system of very limited capacity and of a significantly longer duration
Why does partial report task outperform total report task?
partial report task benefits subject performance presumably because it allows the available information to be sampled
What is Masking in sensory memory?
a process by which the perception and/or storage of a stimulus is influenced by events occuring
What are the 2 ways of masking and what are the 2 main masking types?
- 2 ways:
1. immediately before presentation (forward masking
2. more commonly after the presentation (backward masking) - 2 main types:
1. brightness masking
2. pattern masking
When is the performance better during Brightness Masking?
the brighter the light during the interval, the poorer the performance
-> light is interfering with the memory trace in some way
What were the results of brightness masking according to Averbach and Sperling (1961)?
immediately after presentation subjects knew 14 to 18 items in all conditions
-> as delay increased, information available decreased dramatically especially when the fields before and after the stimulus were illuminated
What is Pattern Masking or Visual Masking?
type of mask occurs when targets are followed by a mask comprising broadly similar features to the target
When does pattern masking operates?
even when the target is presented to one eye and the mask to the other
What does the mask in Pattern or Visual Masking influence?
a later stage of visual processing that occurs after information from the two eyes has been combined into a single percept
What decreased the duration of the iconic memory?
elderly and neurocognitive impairment
-> young subjects (20), estimated duration 340
-> elderly (81), estimated duration 300
-> elderly with mild neurocognitive impairment, estimated duration 70
What are 4 techniques that have been used to measure the duration of iconic memory?
- retroactive masking
- proactive masking
- synchony judges
- phenomenal continuity
What is proactive masking in iconic memory?
occurs when a stimulus is affected by a preceding image, interfering with its perception.
What is retroactive masking in iconic memory?
occurs when a stimulus is affected by an image that appears shortly after, influencing its recognition.
What happens with retroactive masking at 0 ms delay?
The stimuli are processed as a single image, and no interference occurs
What happens with retroactive masking at delays between 0 and 300 ms?
Subjects see an empty circle because the recognition of the first stimulus is interrupted.
What happens with retroactive masking at delays greater than 300 ms?
No interference occurs because the first stimulus has already been processed and transferred to short-term memory
What do synchrony judges in iconic memory research involve?
adjusting the interval between auditory and visual events until they appear simultaneous, defining the duration of iconic memory
when does phenomenal continuity in iconic memory occur?
when alternating a black circle and a white field makes the circle appear continuously present at white field durations of 250-300 ms
What is the estimated duration of iconic memory?
Iconic memory lasts approximately 250-500 ms, though estimates vary by experimental method
What were the results on the scores of the partial reports according to Sperling (1960)?
- scores were practically the same as those of total reports
- subjects could not extract information with accuracy greater than limit of immediate memory (about 4.5 items)
What did Sperling conclude regarding the content of iconic memory?
that the information in the iconic warehouse was uncategorized or in other words at a level of physical characteristics or pre-perceptual analysis
-> idea has been questioned on several occasions
Why is auditory sensory memory necessary?
To maintain the first segments of an auditory stimulus until enough of the signal is received to integrate and understand its meaning
What did Massaro conclude about the duration of the echoic memory?
that it is about a quarter of a second (250ms)
What is auditory persistence?
- first peripheral representation of the auditory stimulus
- contains curde and pre-categorial information
- duration around 250 - 300 ms
-> Massaro’s study
What is Post-categorial Auditory Representation?
results from the processing of Auditory Persistence and contains a perceptual and abstract representation
When is Post-categorial Auditory Representation generated?
After the physical disappearance of the stimulus
How long can Post-categorial Auditory Representation maintain information?
can maintain information for more than 10 seconds, allowing perceptual recognition to be completed
