• Encoding: acquires info, occurs when info is first translated into a
form that other cognitive processes can use. It’s held in storage in one
from or another for later retrieval.
Retrieval: the calling to mind of previously stored info
Forgetting: when we cannot retrieve info
• Clive Wearing’s example
Amnesia, spared memory abilities
TYPES OF MEMORY
Memory is a wax tablet on which impressions are made.
• Modal model of memory (1960s and 1970s)
Info is received, processed, and stored differently for each kind of memory,
according to the length of time info is stored.
Sensory memory: unattended info
Short-term memory (STM): attended info, 20 or 30 sec
Long-term memory (LTM)
• Initial brief storage of sensory info
• Separate sensory memories exist for each sensory modality:
Visual (icon)/auditory (echo)/olfactory/gustatory/ tactile sensory memory
• The Icon
www.notesolution.com The “after-image” of the lightning, or your name, is a mental
experience believed to persist in sensory memory.
Experiment (George Sperling): Recall displayed letters that
were presented for only 50 milliseconds.
Expanding the display time didn’t improve performance.
Even as Ps sere recalling, the info was fading from wherever it
was being stored.
⇒Info lasts only briefly in visual memory system (the icon).
Sperling: Partial-report technique
Visual store could hold abt 9 items, but held only briefly, and
reduced when the tone cue was delayed.
Call this brief visual memory→the icon
Masking: the icon can be erased by other stimuli presented
immediately after the icon.
Ps could be cued to give partial reports in many ways: color,
Info available in the icon is only visual—not auditory or related
to type of stimulus.
• The Echo
“Four-eared” listening task
Condition 1: Ps were asked to report all letters they had heard
Condition 2: Four lights cued the Ps to report only letters from
one particular channel.
→Ps giving partial reports could report proportionately more
⇒The echo stores info only briefly.
Echoic memory has a larger capacity than iconic memory
www.notesolution.com Echoes last longer than icons (20 sec)
e.g. Someone asks you a question while you are watching TV,
can still answer it even after the question has been spoken.
Suffix—recall cue, functions as an auditory “mask” of sorts.
The more auditory similarity there is b/w the suffix and the
items, the greater the suffix effect.
• Properties of sensory memory
1) Sensory memories are modality specific
The visual sensory memory contains visual info; auditory
sensory memory contains auditory info.
2) Visual capacities are larger than auditory sensory memory, but
the length of time info can be stored is longer in the auditory
than visual store.
3) Info that can be stored appears relatively unprocessed.
⇒Most of info has to do w/ physical aspects of the stimuli
rather than w/ meaningful ones.
Guarantees a minimum of time during which info presented to us is available
• Free-recall experiment
Ppl recall a list of words, and then computes the probability of recall of each
word in serial position.
⇒Serial position effect
Recall more words at either the beginning (primacy effect) or the end
(recency effect) of the list than words in middle
www.notesolution.com Participants’ rehearsal help the items enter long-term storage.
→If read the list rapidly enough to prevent rehearsal, the
primacy effect disappears, recency effect stays intact.
The recency effect results from sensory memory or STM.
→If not report right away, and perform an unrelated task, the
recency effect disappears.
Maximum number of independent units can hold in STM is 7
The only way to overcome this limitation is chunking the
individual units into larger units, depends on knowledge.
NFL, CBC, FBI, MTV, more likely to recall
⇒The process of forming chunks is a fundamental process of
memory, an important strategy in overcoming the severe
limitation of having only 7 slots in which to temporarily store
--The way in which info is mentally represented (the form in which the info
Recall consonants, presented visually
Ps were likely to make errors that were similar in sound to the
Formed a mental representation of the stimuli that involved the
acoustic rather than the visual properties.
Even when the stimuli were words rather than letters
→Similar-sounding words make for poor immediate recall,
similar-meaning words don’t.
www.notesolution.com • Retention Duration and Forgetting
Retention duration: if not rehearsed, info is lost from STM in
The Brown-Peterson task:
Present w/ a three-consonant trigram, such as BKG, also give a
number, such as 347, and ask to count backward out loud by
threes (prevent rehearsal).
→Longer counting time, less recall
⇒The memory trace—the encoded mental representation of
the to-be-remembered info that’s not rehearsed—decays, within
abt 20 sec.
e.g. remember phone number.
Some info can displace other info, making the former hard to
Forgetting in the Brown-Peterson task doesn’t happen
until after a few trials.
Over time, proactive interference builds up.
⇒Material learned first can disrupt retention of
subsequently learned material.
• Retrieval of Information
Parallel search: search and exam at the same time.
Serial search: compare one to one
The longer the list, the longer time.
Self-terminating search: stops when a match is found.
Successful searches take less time
www.notesolution.com Exhaustive search: even the match is found, continue looking
through every other item.