Topic 6 Long Term Memory pt 2 Flashcards
This theory follows on evidence suggesting that meaning is represented in the brain based on relevant sensory and motor features
Sensory/Functional theory
memories of color and movement activate which part of the brain?
ventral visual stream (occipital and temporal cortex)
action words activate which part of the brain?
primary motor cortex for specific body parts
which word causes the most activation in the primary motor cortex? (throw, lick, kick)
lick, because it has to do with our face which has the most activation in our face
This theory follows on evidence suggesting that meaning is represented in the brain based on semantic categories
Domain - Specific Theory
How did researchers find that “Domain - Specific Theory” exists? What is the study that was done?
when patients were presented with lesions to different parts of the cortex, they often show word and meaning related deficits related to specific categories
Say you consider thinking about a tool. Where in the brain would you say this is activated?
tool -> premotor cortex because we think about using a tool with our hands.
This fMRI showing activation in the premotor cortex suggests that perhaps both the sensory/functional and the domain-specific theory are correct
how does looking at a hammer and a camel back up the domain specific theory? How does it back up the sensory/functional theory?
looking at a tool and a camel will be activated in distinct parts of the brain (visual cortex). Looking at a tool will also activate the action part of the brain (premotor cortex)
the hippocampus is part of an overall set of structures called the ______________
hippocampus is part of the medial temporal lobe along with surrounding structures (perrihinal, entorhinal, and parahippocampal cortex)
from most rostral to most caudal, what are the surrounding parts of the hippocampus?
perrihinal cortex
entorhinal cortex
parahippocampal cortex
what are place cells
cognitive representation of a specific location in space. It works with other neurons in hippocampus to allow for spatial processing
when do place cells fire?
fire when an animal is in a particular location
what theories try to explain semantic memory?
sensory/functional theory
domain-specific theory
what theories try to explain episodic memory?
cognitive map theory
relational memory theory
what does lesion to the fornix do?
cuts off communication from the hippocampus back to the cortex
define the relational memory theory
theory that suggests that medial temporal lobes are crucial to linking relationships together to form an episodic memory
eg, someone asking you if you remembered the elmo costume party last night, and then you remember how you also ate MandMs that night as well
what is the role of medial temporal lobe?
theories state that different regions of temporal lobes contribute to episodic memories in different ways.
perihinal cortex is focussed on binding features together
describe Hebbian Learning: “neurons that fire together wire together”
when neuron A sends excitatory signals to neuron B and causes an AP, it will strengthen connections-the next time A fires, B will likely to fire again
what is reconsolidation?
when memory is retrieves, the memory is reformed , and it is once again subject to interference
- when memory is retrieves, the memory is malleable once again
function of perirhinal cortex
binding features of objects
parahippocampal cortex
encoding spatial layout
when a presynaptic AP leads to a postsynaptic AP, connections between become ______ (Stronger, weaker)
stronger
Early long term potentiation (2 points)
- increased presynaptic release of neurotransmitter
- increased number of post synaptic receptors
Late long term potentiation (1 point)
- increased number of dendritic spines and synapses (later because it takes longer to grow spines)
define long term potentiation
when a presynaptic AP leads to postsynaptic AP, connections become stronger
define long term depression
(what is it, what happens in LTD, and why do we need LTD) 3 points
- when a presynaptic AP does not leada to a postsynaptic AP, connections become weaker
- reduced NT released, reduced # of receptors, reduced # of synapses
- need LTD to prevent neurons from firing out of control
what does episodic memories (reconstruction) depend on? 5 points
- memory trace
- genes
- past experience
- internal state
- environmental context
true or false: memory is a process of replay
false: memory is a process of reconstruction
James got into a car accident. Witnesses claim it was James’ fault because he ran in front of the car, but James thought he wasn’t even walking yet. What could be the cause of this inaccurate episodic retrieval?
source misattribution
anterograde amnesia
inability to form new memories after surgery
retrograde amnesia
inability to form new memories before surgery
hippocampus (3 points)
- learns rapidly (single trial learning)
- creates distinct memories for each event/instance
- more important for episodic memories
cortex (3 points)
- learns slowly
- extracts generalities across events
- more important for semantic memories
old memories tend to rely on the representations and links in the ______
cortex
recall and reactivation of memories lead to _______.
reconsolidation
what happens if memory is blocked during reconsolidation?
the memory is forgotten
true or false: when a memory is formed, it is more or less important
False; this is an old construct
The new idea is that in reconsolidation, when a memory is retrieved, the memory is reformed and it is once again subject to interference.
