Lecture 8 Flashcards
What does learning mean ?
Process by which experiences change our nervous system and hence our behaviour
What is the relationship b/w learning and memory ?
- Linked
- Typically studied together
- to remmeber what you learn it has to be coded
Who pioneered classical conditioning ?
Ivan Pavlov
What is classical conditioning ?
Type of conditioning produced by the pairing of two stimuli, one which evokes an automatic response
* these two stimuli changes the response to one of them
What is a conditioned stimulus ?
stimulus that intially elicits no response
What is a unconditioned stimulus ?
stimulus that automatically elicits a unconditioned response
What is a unconditioned response ?
Response automatically evoked by a unconditioned stimulus
What is a conditioned response ?
response evoked by a conditioned stimulus after it has been paired with an unconditioned response
Who is the Father of Behaviourism ?
John B. Watson
What is behaviourism?
All behaviour are acquired through conditioning
Who is the Mother of Behaviour Therapy ?
Mary Cover Jones
What is extinction ?
the gradual weakening of a conditioned response that results in the behavior decreasing or disappearing
What was the Case of Peter (1924) study?
- Peter was 2 yrs and 10 months and was scared of white rats
- A white rabbit was shown to him and elicited fear
- A white rabbit was shown again and then was tied to the food that he liked and this reduced his fear
- Direct conditioning (a.k.a., desensitization) - end of experiment Peter has a postiive response
What was Pavlov’s proposal ?
After training, excitation in CS center flows to UCS center, which elicits the same response as UCS
What occurs before traning ?
Initially, the UCS excites the UCS center, which excites the UCR center. The CS excites the CS center, which elicits no response of interest
What is an engram ?
Physical representation of what has been learned
Who looked at localization with engrams ?
Karl Lashley
What did Lashley reason ?
Reasoned that if memories were connections between brain areas, they could be severed with a knife
What did Lashley test this one ?
Lashley trained rats on mazes and takss, then made cuts to the cortex to try to disrupt performance
What did Lashley find ?
Cuts did not impair performance
* Learning did not depend on connections across the cortex
Learning did not depend on a single area in the cotex
* Taking out a chunk of cotex impaired performance, but it was about the chunk take, not the cortical area itself
What are the two principles that Lashley proposed ?
- Equipotentiality
- Mass action
What is equipotentiality ?
All parts of the cotex contrubute equally to complex functioning behaviours (e.g., learning) and any part can substitue for any other
What is mass action?
The cortex works as a whole and more cortex is better
Who conducted the modern search for the engram ?
Richard F. Thompson
What did Thompson study ?
Studied classical conditioning of eyelid responses in rabbits
What were the CS, UCS, and UCR-CR in Thompson’s study ?
- CS: Tone
- UCS: Air-Puff (to rabits eye)
- UCR-CR: Eye-blink
What was presented to help figure out this location ?
A sequence of brain areas from the sensory receptors to motor neurons controlling the muscles
Sensory -A-B-C-D-E-F- Muscles
How does this sequence work ?
E.G: If D is in charge of learning, damage to either A,B, or C will prevent learning by blocking the input to D. Damage to E or F will prevent learning by blocking output from D
* damage essentially will impair or eliminate a learned response - breaks connections
* D must be active at the time of learning and so does A,B, and C
* Learning should not require E and F
Which brain area is essential for learning ?
Lateral interpositus nucleus (LIP)
* located in the cerebellum
What did research find on the LIP ?
- When LIP was surpressed training had no effect
- But when it recovered, rabit learned at the same speed as animals that had received no previous training
What is the red nucleus ?
a midbrain mortor area that received input from the cerebellum
What occured when the red nucleus was surpressed ?
Learning was still occuring in LIP
What occured when the red nucleus recovered ?
Learned and able to send it
What was the overall results of the study ?
- Learning is instantiated in the lateral interpositus nucleus (LIP)
- Red nucleus is required to demonstrate the learning (i.e., execute the eye blink)
Who is the founder of Operant (Intrumental) Conditioning ?
BF Skinner
What are the two things involved in operant conditioning ?
- Reinforcement
- Punishment
What is reinforment ?
Increases the occurence of a response
What is positive reinforcement ?
Desreiable stimulus added to increase the liklihood of behaviour
i.e.,: Giving a child a sticker; allowance for doing chores
What is negative reinforcement ?
Undesireable stimulus is removed to increase the likelihood of a behaviour
i.e.: taking chores away for doing good on a test
What is punishment ?
Decreases the occurence of a response
What is positive punishment ?
Unpleasant stimulus that is added to decrease the liklihood of a behaviour
i.e.: spanking, scolding a child
What is negative punishment ?
Desrieable stimulus remvoed to decrease the. likelihood of a behaviour
i.e.: removing toys, video games
What is continuous reinforcement ?
The desired behaviour is reinfocred every single time it occurs
example: traning your dog to sit with biscuits
What is intermittent reinforcement ?
Once the response is established, the response is reinfoced only part of the time
i.e.,: getting paid every two weeks, giving a chilf screentime following a tantrum sometimes
What two things fall within intermittent reinforcement ?
- Fixed-ratio or Variable ratio (# responses)
- Fixed-interval or Variable interval (amount of time)
What are the two main differences between operant and classical conditioning ?
- One is responsive (CC) and one is voluntary (OC)
- Order
* Behaviour before stimulus (OC)
* Stimulus before behaviour (CC)
How does operant conditioning work in the brain ?
- Depends on the type ( positive/negative or reinforcement/punishment)
- Positive Reinforcement occurs in the brains reward system
What is statistical learning ?
The ability to perceive and learn regulairites
e.g: in language, such as the speech soudns that compromise a word
What develops early regarding changes in statistical learning ?
- Caudate
- Putamen
- Primary sensory
What develops late regarding changes in statistical learning ?
- Inferior temporal
- Middle temporal
- Hippocampus
What is perceptual learning ?
Learning to recognize things
What does perceptual learning involve ?
Involves perceptual changes from practice or experience
What are the mechanisms used in perceptual learning ?
- Attention weighting
- Imprinting
- Differentiation
- Unitization
What is relational learning ?
Involves learning the temporal and spatial relationships among objects and events
What are the details of Short Term Memory ?
- Limited cpacity
- Fades without rehearsal
- Usually more contextual detail than LTM
What are the details of Long Term Memory (LTM) ?
- Unlimited capacity
- Indefinite storage time
- Stimulated with cue/hint, unlike STM
What is consolidation ?
Action or process of. making something stronger in your LTM
* repetition, giving something meaning and associatiate it with prior knowledge
* occurs from STM to LTM
What brain areas are associtated with memory ?
Medial Temporal Lobe
* Hippocampus
* Basal Ganglia
What is the hippocampus vital for ?
Vital for declarative/episodic memory
When is the hippocampus active ?
- Memory formation
- Memory recall
- Imagining future events
What is the hippocampus important for ?
Important for visual spatial memory
What cells does the hippocampus have ?
Cells responsible for spatial memory
What are the names of the cells located in the hippocampus ?
Place Cells and Time Cells
What do Place and Time cells do ?
Fire in resoinse to spatial locations and temporal information
What is the name of the cells located in the ERC ?
Grid cells
What do Grid Cells do ?
hexagonal grid forming a coordinated system that allows for spatial navigation
What is the Basal Ganglia involved in ?
Involved in implicit learning of patterns and habits
What is the anatomy of the basal ganglia ?
Straitum
* Dorasal striatum - Caudate nucleus & Putamen
* Ventral striatum - Nucleus accumbens & Olfactory tubercle
What is semantic memory ?
Object knowledge learned over many interactions
What is episodic memory ?
Memory for specific events that you have experienced
What is explicit memory ?
Conscious
What is implicit memory ?
Unconscious
What is declarative memory?
Facts and events
What is procedural memory ?
Skills and tasks
i.e: how to ride a bike
What is autobiographical memory ?
The imformation and memories individuals accumulate that creates a unique idenitty and a person sense of continuity
How are brain patterns during memory ?
Similar to perception
What are the two components of memory ?
- Episodic (specific personal events)
- Semantic (general world knowledge)
How is autobiographical memory seen in the brain ?
- More connectivity between the hippocampus and visual processing when recalling episodic memories (left precuneus)
- The hippocampus and medial prefrontal cortex are involed in semantic memory
What are some disorders of memory ?
- Amnesia
- Severely Deficient Autobiographical Memory (SDAM)
- Korasakoff’s syndrome
- Dementia
What is retrograde amnesia?
Can’t remember life before the injury
What is anterograde amnesia ?
Can’t make new memories
What was done to Henry Molaison aka HM ?
His hippocampus was removed
What happened to HM?
Bilateral medial temporal lobe removed
* Severe anterograde amnesia - No new episodic memories
* Some retrgrade amnesia
Working memory intact
* Inability to form new memories - explicit/episodic
Procedural learning intact
What is infantile amnesia ?
The inability of humans to remeber episodic expriences that occured during the first few years of like (generally 0-3)
What explains infantile amnesia ?
Immaturity of hippocampal system
* Critical period - hippocampus is highly responsive to environmental expreriences might impede storage of episodic details
Input of experiences causes hippocampal system to mature and develop
What occurs in SDAM ?
Healthy people report a failure to reexperience or recollect specifc events from their past, although their memory for factual information about themselves and the world is intact
What is aphantasia ?
Inability to visualize in the minds eye
What is involved in Korsakoff’s syndrome ?
- Thaimine deficiency
- Loss of neural activity throughout the brain, especially dorsomedial thalamus
- Hallmark: confabulation (“honest lying”)
What is involved in Dementia ?
- Semantic Dementia: Anterior temporal cortex
- Frontotemporal Dementia (FTD): Frontol and anterior temporal
- Alzheimers Disease: Hippocampus
