Chapter 6 & 7 - Long-term memory Flashcards
Three ways to distinguish between different types of memory
We will do this by considering the results of
(1)behavioral experiments,
(2)neuropsychological studies of the effects of brain damage on memory, and
(3)brain imaging experiments.
serial position curve - whose experiment does this stem from? What is the experiment? What two things do the results indicate?
Murdock
a memory experiment in which participants are asked to recall a list of words, a plot of the percentage of participants remembering each word against the position of that word in the list
indicates primacy effect and recency effect
primacy effect - what is it and what does it indicate?
memory is better for words at the beginning of the list
rehearsal - encoding into LTM
recency effect - what is it and what does it indicate?
most recent info is likely to be the first remembered -
STM encoding
what would happen if you had to count backwards during the serial position curve experiment?
you would erase the recency effect because those last few words wouldn’t stay in STM but the primacy effect would still occur because the rehearsal encodes them into LTM
what do the primacy and recency effects provide evidence for?
separation between STM and LTM
Coding
the form in which stimuli are represented in the mind. For example, information can be represented in visual, semantic, and phonological forms.
Examples of visual coding in STM and in LTM
visual coding in STM if you remembered the pattern by representing it visually in your mind
visual coding in LTM when you visualize a person or place from the past
Examples of auditory coding in STM and in LTM
Auditory coding in STM is illustrated by Conrad’s demonstration of the phonological similarity effect
Auditory coding occurs in LTM when you “play” a song in your head.
Examples of semantic coding in STM and in LTM
semantic coding in STM - Wickens experiment (fruits, professions, etc., word lists):
proactive interference
release from proactive interference - that occurs in the Wickens experiment depends on the words’ categories (fruits and professions)
Semantic coding in LTM - Sachs experiment:
had participants listen to a tape recording of a passage and then measured their recognition memory to determine whether they remembered the exact wording of sentences in the passage or just the general meaning of the passage
The finding that specific wording is forgotten but the general meaning can be remembered for a long time has been confirmed in many experiments
Recognition memory
Identifying a stimulus that was encountered earlier. Stimuli are presented during a study period; later, the same stimuli plus other, new stimuli are presented. The participants’ task is to pick the stimuli that were originally presented.
what is the predominant type of coding in STM?
auditory coding (rehearsal)
what is the most common form of coding in LTM tasks?
semantic coding
the strongest evidence for separation of STM and LTM in the brain is provided by what?
neuropsychological studies
Case of HM - what brain area affected? what was result of brain change? what did this change indicate about memory?
removal of hippocampus due to seizures
eliminated ability to form new LTM
STM remained intact
suggested that short-term and long-term memories are served by separate brain regions
hippocampus - where is it and what relation does it have to memory?
subcortical structure in the temporal lobe - important for forming LTM and also plays a role in remote episodic memories and in short-term storage of novel information
Case of KF -what brain area affected? what was result of brain change? what did this change indicate about memory?
damage to parietal lobe in motorbike accident
poor STM indicated by reduced digit span (2 digits)
recency effect was reduced
had functioning LTM indicated by abiity to form and hold new memories of events in life
together with HM, he establishes a double dissociation - supports that STM and LTM are caused by different mechanisms which can act independently
Can the hippocampus hold info for short periods of time? How do we know about this?
Ranganath and D’Esposito - brain scan while viewing familiar and novel faces experiment
concluded that the hippocampus is involved in maintaining novel information in memory during short delays
show that the hippocampus and other medial temporal lobe structures once thought to be involved only in LTM also play some role in STM
Tulving suggested that episodic and semantic memory can be distinguished based on the type of _______________ associated with each
experience
mental time travel
the defining property of the experience of episodic memory, in which a person travels back in time in his or her mind to reexperience events that happened in the past
experience of self-knowing or remembering
How does Tulving describe the experience of semantic memory?
knowing - does not involve mental time travel
neuropsychological evidence of episodic/semantic memory separation
case of KC - motorcycle accident - damage to hippocampus and surrounding structures
- lost episodic memory but semantic memory largely intact
case of LP - Italian woman - encephalitis
- severe impairment of semantic memory but maintained episodic memory
(double dissociation)
two ways that episodic and semantic memories interact in everyday life
how knowledge (semantic) affects experience (episodic) - knowledge (semantic memory) guides experience and influences episodic memories that follow
the makeup of autobiographical memory - can include both episodic and semantic components
personal semantic memories
semantic memory that is associated with personal experiences
(e.g., the table near the window is our favourite one, that table is difficult to get in the morning)