Exam3Lec3IntrotoLearningandMemory Flashcards
What is learning?
Connections grown between areas of the brain. Led to the search for localized representations of memory.
Basically: networks of neurons activated to convey contextual info.
remember: Hippocampus strengthens and amplifies memory
Cortex stores memory
What is engram?
An old term used to describe a physical place when stimulates a specifc memory comes up
An inferred change in an organisms mental state which results from experience and which influences in a relatively permanent fashion an organism’s potential for subseuquent adaptive behavior
Learning
What are the 2 types of memory?
- Memory currently active in the cortex
- Long term memory consolidated by hippocampus
we DONT have “short term memory”
How do we make a memory?
- Attend to the memory
- Encode the memory/consolidate it in the hippocampus
- For Retrieval of memory from cortex and bring it back into the working space
Sensory memory , Working memory and
Long term memory lasts how long?
- Sensory memory: 1-3 secs (lasts as long as the stimulus is actually activating the network
- Working memory: 15-30s (can last longer if you keep repeating/resetting it)
- Long term memoryy: 1s to lifetime (anything stored from a second to years)
What is phylogentic/epigentic memory? Give an example
Memory that is passed down
EX: smaller animal as soon as its born learning to avoid predators based on the shape of a shadow that has been passed along by genetics
you see changes in actual histone structue around your DNA that allos certain rly impt pieces of info to be passed along
What are the 2 types of informational systems and mention their cycle duration?
- Phylogenetic/Epigentic memory: a cycle duration of genrerations (weeks-yrs), useful to a species
- Behavioral memory: cycle duration of minutes to days, only value to an indiv
Explain the case with Henry Gustav Molaison (H.M)
His hippocmapus was removed to prevent epileptic seizures.
He had difficulty forming new long term memeories (anterograde amnesisa)
STM or working memory remained intact
He could remeber his childhood and he has the ability to learn new tasks and act on the, he could not store new long term memories.
What did the HM case suggest?
That the hippocamous (medial-temportal cortex) is vital for the formation of long term memories
Patient HM displayed greater implicit than explicit memory. What is the difference between the two?
Explicit memory: deliberate recall of info that one recognizes as a memory (declarative)
Implicit memory: the influence of recent experience on behavior w/o realzing one is using a memory (a specific form of non declarative, such as biasis/prejudices)
explicit: conscious of it
implicit: not consciosuly aware of it
HM had difficulty with episodic and declarative memory. What is the definition of these?
Episodic: ability to recall single events
Declarative: ability to state a memory into words
episodic is a subcategory of declarative
HM had trouble with semantic memory. What is this?
Understanding definitions and symbolism
sematic is a subcategory of declarative memory
ex: understanding a crosswalk or stop sign
HM’s procedural memory (nondeclarative) memory remained intact. What is procedural (nondeclarative) memory?
The ability to develop motor skills (remembering or learning how to do thing)
this is independent of the hippocampus
“Cells that fire together, wire together” describes which type of learning?
Hebbian Learning
hippocampus allows us to amplify circuits and turn them into memories
only cells that are active during the memory will form a networl
What is Hebbian learning?
- Stimulation of one neuron by another neuron enhances that connection
- This incr effectiveness b/c simultaneous activity in pre and post synaptic neurons
- critical for associative learning
Ex: if you eat blue jello and immediately get sick to your stomach, you might have blue color associated with it aling with the taste, feel, and look of jello associated with disgust circuit
What are two processes involved in storing information in the Nervous system?
Habituation: learn and decr response over time with a stimulus
Sensitization: learn and incr respnonse over time with a stimulus
What is habiutation and what does it depend on?
A decr in response to a stimulus that is presented repeatedly and accompanies by no change in other stimuli.
Depends upon a change in the synapse b/w the sensory neurons and the motor neurons
sensory neurons fails to excite motor neurons as they did previosuly
allows us to gate out everything going around you and focus on whats relevant
Explain habitutation with the sea slug
- Touch the siphon and it has a withdrawl reflex.
- As you keep touching the siphon, the gills stop withdrawing and ends up habituating.
- This occurs bc a decr in signaling cascade b/w sensory and motor system and you have both pre and post synaptic loses and internalize the receptors so they cant be activated anymore
What is sensitization and state the main NT involved in this processes?
An increase in response to a mild stimulus as a result of previous exposure to more intense stimuli.
Serotonin released from a facilitating neuron blocks potassium channels in the pre-synaptic neuron. Prolonged release of NT from that neuron results in prolonged sensitization
ex: you get a shot and at 1st it doesnt bother you, but then you have a horrible allergic reaction to the shot and you feel horrible afterwards, You have a much stronger physical respone to that cue if someone tries to give you a shot again.
Explain sensitization with the sea slug
When you tap the tail of the slug, it has a much stronger withdrawl response. When you tap the tail at the same time as tapping the siphon you get a very strong response. The tail and the siphon are now associated and you get an equal response
What is Long-term Potentiation (LTP)?
Occurs when 1 or more axons bombard a dendrite with stimulation.
* Leaves the synapse “potentiated” for a period of time and the neuron is more responsive to any stimulus
“strengthening of connections”
neuron A has a better chance oif exciting neuron B the next time the que is presented
What is Long term depression (LTD)?
A prolonged decreased in response at a synpase that occurs when axons have been active at low frequency
decr likelihood that neuron A can turn on neuron B
not the same as forgetting, that is breakdown of connections
How can therapy for PTSD induce LTD?
You can flood a PTSD pt with a traumatizing stimulus in a safe environment. They won’t forget about the trauma but will go through LTD. Stimulus/neuron A is still there but its not activating neuronB b/c nothing bad is happening. Neuron B will not respond to neuron A.
What are the 3 properties of LTP?
- Specificity
- Cooperativity
- Associativity
What is specificity of LTP?
Only synpases that have been highly active in response to que become strengthened
only specific ques will be strengthened
Blue jello ex: red, yellow jello parts won’t be included bc its part of a diff circuit and wont be activated in response to same process, only specific ques linked to process
What is cooperativity of LTP?
Simultaneous stimulation by 2 or more axons produces LTP much more strongly than does repeated stimulation by a single axon
* Spatial summation is more potent than temporal stimulation
What is the overall concept of this image?
That the most impt part of learning is associativity. After the event, if something has been weakly activated, it will be strengthed just like all those initial strong inputs
