Memory Flashcards
basic model of declarative memory- encoding
features are remembered in same sensory/motor areas involved in encoding those features
hippocampus stores ‘index’ of event
basic model of declarative memory- storage
memories are strengthened and consolidated during a storage phase
if they’re not strengthened, they’re forgotten
basic model of declarative memory- retrieval
internal/external cue used to trigger retrieval of memory
temporal lobe serves to coordinate info in cortical regions
memories can be retrieved w/o access to medial temporal lobe
frontal lobe & declarative memory
plays a role in semantic/linguistic processing that is important for encoding and retrieval
e.g. connecting info w existing knowledge, and guide search
also plays role in working memory
parietal lobe & declarative memory
important for attention processes
direction attn appropriately for the encoding and retrieval of memories
short term / iconic & echoic memory
i.e. short term visual & sound memory
duration can be determined by looking @ event related fields in MEG –> find that a deviant tone is no longer distinguished after 10 sec –> can retain high amt of info for a brief time
medial temporal lobe anatomy
hippocampus, parahippocampal cortex, perirhinal and entorhinal cortices
medial temporal lobe connectivity
various areas of cortex –> perirhinal & parahippocamopal cortices –> entorhinal cortex –> hippocampus
hippocampus well positioned to integrate info from multiple cortical regions into a single memory or event
cognitive map theory
hippocampus plays a role in memory for the spatial relationship among items (taxi drivers’ hippocampi)
relational memory theory
hippocampus plays a role in memory for new associations, not just spatial ones (tested using odor associations in rats)
lesions to hippocampus disrupt the ability to learn this associative relationship across pairs
episodic memory theory
hippocampus plays a role in episodic memory rather than semantic memory
(patient KC that had lesions to hc had impaired episodic memory for events, but spared semantic memory)
hippocampus activates only for recognition
role of MTL in encoding and retrieval of episodic memory- Ranganath
studied 360 items presented in diff colors during fMRI scanning –> memory for items tested outside of scanner
hippocampus & parahippocampus more active when source info later remembered
role of MTL in encoding and retrieval of episodic memory- Eldridge
measured activity in hc during memory recall –> hippocampus activity only for ‘recollected’ items, not when items were correct, but only familiar
- suggests a role for hc in episodic recollection
role of MTL in encoding and retrieval of episodic memory- familiary based encoding
BOLD measure of familiarity based recognition found activity in entorhinal cortex, NOT in hc
*suggests dissociation bet hc and entorhinal cortex
role of MTL in encoding and retrieval of episodic memory- false memory
Cabeza had participants listen to related words , performed old/new recognition using new & false words –> hc did not distinguish bet true and false words
parahippocampal gyrus active only for true words
hippocampus active in response to context & relationships of the words, like episodic memory
item in context model
perirhinal cortex involved in memory for objects (input from ventral pathway)
parahippocampal cortex encodes info relevant to spatial relationships (input from dorsal pathway)
hippocampus encodes item (object) in its context (relationships)
*explains why perirhinal is related to familiarity and hc to recollection
sensory/functional theory
knowledge is remembered in the same sensory/motors regions as encoding for that knowledge
retrieving memories activates regions of the brain associated w processing of the specific feature being recalled
e.g. action words –> motor areas, and sound words –. auditory areas
banjo/train study
*suggests distributed storage of memory
posterior parietal cortex (PPC) in retrieval
dorsal parietal cortex –> familiarity, low-confidence, more active when items are subsequently remembered
ventral parietal cortex –> recollection & high confidence recognition, more active when items are subsequently forgotten, associated w failed memory during encoding, and successful recollection during retrieval
- ventral = inward direction of attn, outward = distraction –> forgetting. effective during retrieval
- dorsal = outward direction of attn. inward = distraction. effective during encoding
