This site is 100% ad supported. Please add an exception to adblock for this site.

PY 1 Exam 2 Review: Memory

Terms

undefined, object
copy deck
Memory
a highly complex and structured system that enables organisms to record facts about the outside world and use them to guide behavior.
Ebbinghaus idea
(1870s) was the memory pioneer. Used himself as the subject. He accepted the British Empiricist idea that ideas are linked by contiguous associations and that memory did not have a special structure (we now know that this is wrong). To get around the problem of already associated words, he used paired, non-verbal syllables (three letters with vowel in the middle). This method is now known as paired associate learning.
Ebbinghaus experiment
He needed a way to evaluate the recall: Savings. (# of trials needed to learn list - # of trials to relearn list after retention interval)/# of trials needed to learn list) x 100. His basic result was that lots of forgetting happens early in the retention interval (forgetting curve) and then it becomes gradual. Relearning has a more gradual decline than recall. (Note: his decision to use nonsense syllables severely inhibited the subjects’ ability to store them in their LTM.)
Simple decay
the idea that, as time passes, memory spontaneously falls apart (through some sort of metabolic deterioration). However, evidence contradicts this. (Memory declines more rapidly when doing activities than when sleeping.)
Interference
Underwood analyzed Ebbinghaus’ data and found that as he learned more lists he remembered less. The lists seem to interfere with each other! New learning promotes the forgetting of old items.
. Retroactive interference (or inhibition)
you retain less after learning something new than you do after resting.
Proactive interference
previous learning interferes with new learning.
Explanations of forgetting:
Response competition, unlearning, motivated forgetting, brain changes
1. Response competition
Confusion between similar stimuli results in a wrong answer (hence forgetting).
2. Unlearning
S-R bond becomes extinct (not much evidence for this).
3. Motivated forgetting.
Freudian idea that we suppress painful memories.
4. Brain changes.
Aging and certain diseases cause degenerative neural processes.
William James
(1900) pointed out two stages of memory- primary and secondary
Primary (short-term, working) memory
The memory of events that have not left consciousness. Someone tells you their phone number and a few seconds later you write it down. Conscious awareness of the moment. New mental items come in and others leave.
Secondary (long-term) memory.
The memory of events that have not been in consciousness for some time but can still be recalled. (You recall the phone number a week later.) Everything we have experienced, what we mean by “self.”
Episodic memory-
memory for a specific fact/event/episode.
Generic memory-
our mental reference library,⬝ common sense, what words mean, how many months in a year. Think top-down.
Explicit memory
aware that we are trying to remember
Implicit memory-
memory without awareness of it (like solving a puzzle faster a second time with no recollection of solving it the first time)
Three steps of memory:
Acquisition, Storage, Retrieval
Acquisition
(first stage, processing/paying attention, how information is encoded into memory. You can focus on certain events but not others, creating errors.)
Storage
encoded experience must leave a memory trace (a record in the nervous system.)
Retrieval
when we try to remember. Two types. Recall (response to specific question or cue, like short answer test). Recognition (asked if we remember, like multiple choice).
The Serial Position Effect
supports James’ theory. U-shaped recall graph for a memory span task (learning items and then repeating them). The performance on the first few items (primacy effect- more opportunity to rehearse, gets more attention) and last few items (recency effect) is good; the middle performance is poor.
The Stage Theory of Memory
items are moved from STM to LTM, but many are lost before transfer due to STM’s limited capacity. Items can be held in STM longer by rehearsal (mere repetition of items), thus increasing the chance that they will be moved to LTM. Funnel analogy. Memories are like objects put into different storage compartments for different purposes.
Why the Serial Position Effect makes sense
If recall is delayed and mental activity is required (like a math problem) then the recency effect is abolished because mental activity requires “space” in STM, causing overflow and loss. Primacy effect: transfer is good due to small number of items in STM, more rehearsal. Middle effect: many items are lost due to overflow; rehearsal can only deal with a few items. Recency effect: recent items are moved into LTM before most are lost.
STM (working memory):
temporal span of < 1 min, capacity of & + 7 items, organized by chunking, forgetting due to displacement because of limited capacity or decay (unlikely because passage of time is just one piece of the puzzle).
LTM
temporal span of years, even organism’s lifetime, huge capacity, complex organization of clustering, meaning, and hierarchy, forgetting due to interference, motivated forgetting, response competition, and brain changes.
Peterson and Peterson’s experiment:
when asked to perform arithmetic to prevent rehearsal, recall of three letters declined greatly, hitting zero after about 18 seconds. However, with a less distraction task (allowing for rehearsal), very little loss occurred. Under normal circumstances (which involve lots of distractions), STM is limited to a minute or so because of interference. STM’s limited capacity means that new items force old items out, and only transfer to LTM can save them.
Chunking (known as recoding)
The 7+ 2 items concept is consistent with the passive “loading dock” analogy. However, what is an item? Items can be grouped together (245908 turns into 245-908, like a phone number), process known as “chunking.” Chunking (known as recoding) increases STM’s capacity by allowing more information in each item.
Workbench view
Chunking complicates the loading dock view. something (a strategy residing in the LTM) was done to the individual items to organize them. As a result, STM is now considered to be a “work bench” that is influenced by LTM. More is involved in memory transfer than mere rehearsal.
Repetition priming
(14 and carrot) LTM
Clustering:
items are clustered by the LTM system relating to the meaning of the items. Facilitates both remembering and misremembering.
Hierarchy in semantic memory
network models. Items in LTM are arranged with respect to the generality of their application, with general above specific. RT is longer the larger the level difference in the sentence. So, for canary, characteristics specific to canaries come faster than those general to all birds.
Retrieval cues:
stimuli that open the path to memory, triggers (smells, sights, etc). Memory is best if the context at the time of recall is similar to the context at the time of learning. This suggest encoding specificity, which means that ideas and events are encoded within a particular context and that retrieval is best when that context is recreated.
permastore):
Permanent storage. memory is very important or was learned very well.
Retention interval (time between learning and retrieval)
Depth of processing-
shallow (superficial characteristics, like the typeface of a word) vs. deep (meaning, better recall).
Mnemonics-
techniques for improving memory.
Flashbulb memory
extremely vivid memories of specific (often highly emotional) events. But, probably kept in mind due to rehearsal or incorrectness, and not because of a separate mechanism.
Schema
general framework into which data/events can be entered, based highly on prior experience.
Hypnosis
improves sureness of a memory but not accuracy.
Practical applications (maintainence vs. elaborative rehearsal)
do not just memorize (maintenance rehearsal- keeps something in STM but doesn’t usually transfer to LTM). Think about material and look for connections with already-learned material, building another path that allows for memory access (elaborative rehearsal).
Localization of memory
in the brain: when cortex of dog was removed, some classical conditioning was possible but operant conditioning was minimal. The cerebral cortex is obviously where to look for learning and memory in the mammal (but birds, for instance, have memory but no cortex). Many areas have specific functions (primary sensory/motor areas), and those without specific functions are thought to be the “associative cortex,” where memory and learning occur.
Lashley’s engram quest:
defined the engram as the physical trace of memories and thought that specific memories were in specific parts of the cortex. He taught animals specific things and then lesioned specific parts of the brain and tested for recall. Result? Could not find engram
the Law of Mass Action
However, he did derive the Law of Mass Action: the degree of memory deficit is in proportion to the amount of cortex destroyed, not its location. Specific memories are stored in a distributional network, not at a tiny site, but there are some exceptions:
delayed response problem:
Damage to frontal lobe cortex. Lessioned monkeys cannot identify the cup with food; they have no STM.
oddity problem
Damage to the posterior association area. Normal mammals can easily learn the oddity problem: rewarded for choosing the odd target in a visual discrimination (circle out of squares). But, lesioned animals cannot do it. This reflects an inability to use memories in LTM to develop a strategy.
Anterograde amnesia- surgery
Damage to the hippocampus. Prevents transfer from STM to LTM. In 1950s, HM was treated for epilepsy by lessioning the hippocampus. His epilepsy disappeared but so did aspects of his memory.
Anterograde amnesia- what resulted from it
His LTM has normal (remembered his name, family, etc), and he had some STM (like remembering a phone number). However, he couldn’t enter STM info into LTM; couldn’t recall a new phone number since surgery. He could not learn new facts (no new declarative memory, similar to explicit memory). But, he could learn new skilled motor tasks, procedural knowledge (procedural knowledge, similar to implicit knowledge). Similar problems in Korsakoff’s syndrome (caused by alcoholism) and Alzheimer’s.
What changes in the brain when we learn?
Reverberating circuits (A is activated, which activates B, then C, then B again).
(Retrograde amnesia)
Electroconvulsive shock (to treat depression) disrupts STM of previous events before surgery but not LTM, suggesting that it is not the basis for LTM but maybe STM. (Retrograde amnesia)
Anatomical changes:
LTM requires some change that is substantial, e.g. resists electroconvulsive shock. Change includes growth of new synapses, functional changes of synapses (more efficient), molecular/DNA/RNA basis (possible because it directs protein production but certainly not proven).

Deck Info

52

permalink