Chapter 5 Flashcards
Taste aversion learning
After becoming sick due to food, the item itself becomes a warning stimulus for sickness
What are the explanations for taste aversion
Laws of classical conditioning
Law of effect (probability to repeat a situation based on outcome)
Problems with classical conditioning explanations of taste aversion
One trial acquisition (one count food poisining)
Delayed conditioning (doesn’t get sick for 10+hours)
Selectivity in taste aversion learning (wont link with other paired stimuli)
Is extinction more likely to occur in classical conditioning or one shot learning?
Classical conditioning
One shot learning is highly resistant
Blocking ( the rescorla-wagner model)
Group A: group B
pre-training- none. Pre training- noise = shock
Conditioning -noise + light = shock. Conditioning -noise + light = shock
Testing-light. Testing-light
Response- freezing (high fear). Response - Bar pressing (no fear)
Fear of light is not learnt bc associative strength has been used up by noise shock pairing
Natural selection 3 key features
1.all individuals are unique behaviorally and physiologically
2. Traits are heritable
3. Typically competition for important resources
Instinctive drift
Refers to the tendency of organisms to revert to instinctual ,unlearned behaviours
Ex. Training pig to drop money = inset chive drift of digging behaviour
Hindbrain
Lower brain stem responsible for basic physiological functions such as respiration and heart rate
Houses cerebellum which is involved in locomotion and balance
Midbrain
Upper brain stem responsible for waking and sleeping and for controlling general arousal
Nerve fibers associated with movement
Forebrain
Largest most complex brain structure
Includes: hypothalumus,thalamus, limbic system, cerebrum, cerebral cortex
Learning can take 4 basic forms
- Perceptual learning
- Stimulus-response learning
- Motor learning
- Relational learning
Perceptual learning
Any info coming in through senses and being processed
Stimulus- response learning
Ability to learn to perform a particular behaviour when a particular stimulus is present
Involves establishment of connections between circuits involved in perception and movement
Neural model of classical conditioning
Sensation (puff of air to the eye) → Neuron in somatosensory (eyes) natural response is to blink. Therefore synapse is strong
Sensation ( 1000-hz tone) → neurons in auditory system, no natural response of blinking to a tone. Therefore synapse is weak - however, it can be strengthened over time through classical conditioning
Hebb rule
If synapse repeatedly becomes active at same time that the post synaptic neutron fires, changes will take place in structure + chemistry of the synapse that strengthen it
If weak and strong neuron are activated together. Weak neuron will eventually become strong
Classical vs instrumental conditioning
Classical: reward is delivered independently of behaviour
Instrumental: behaviour causes reward to appear
Neural model for instrumental conditioning
Stimulus → neural circuit that detects and processes a particular stimuli (perceptual system) → neural circuit that controls a particular behaviour (motor system) → desired behaviour → reinforcing stimuli
Reinforcement system strengthens connection between perceptual and motor system
Motor learning
Changes within motor system
What is motor learning dependant on?
Sensory guidance from the environment (perceptual system)
Overview: perceptual, s-r, motor learning
Stimulus → perceptual system → s-r learning → motor learning → response
Long-term potentiation
A particular neuron changes the way its behaving in terms of its voltage
Potentiation =increase in receptors
Hippocampal formation ( used in memory formation)
Series of structures that work together in a circuit (activity in one part of formation effects activity in another part)
How can you measure a charge?
Using an electrode
How can you give a neuron some charge?
Electrode
How do we measure change/stimulation in hippocampal formation?
Repeatedly stimulating axon in perforant path with electrode and recording voltage from a neuron in dentate gyrus
What does hippocampul long term pontentiation simulate?
Hebbs rule
Long term depression
Low-frequency stimulation of the synaptic inputs
A long-term decrease in the excitability of a nueron to a particular synaptic input
Ex. After this class you want study this material (low frequency stimulation) and it will be forgotten
Is long term depression hyperpolarization or polarization
Hyper-polarization
Perceptual learning
Involves learning to recognize things (perceive) not what to do when they are present
Ventral stream
What? Stream
Object recognition
Continues into the temporal cortex
Dorsal stream
Where? Stream
Location of objects
Continues into parietal cortex
What responses can an aversive stimulus produce
Behavioural: freezing
Autonomic: increased blood pressure
Hormonal: secretion of adrenal
Where does the amygdala (emotion control) receive its information from?
Lateral nucleus
What is the primary function of the basal nucleus?
Stimulating fear response
After info is received from lateral nucleus -→ the basal nucleus stimulates fear
After the basal nucleus receives info from the lateral nucleus, where does it go?
Central nucleus
What are the two major pathways between the sensory association cortex and the motor association cortex
- Direct transcortical connections thalamus
- Connections vid the basal ganglia and thalamus
What are involved in our pleasure areas?
Ventral segmental area
Nucleus accumbens
What two functions must any reinforcement systems perform?
- Detect presence of reinforcing stimulus
- Strengthen connections between neutrons that detect the stimulus and ones that produce responses
Reinforcement: VTA
Has dopaminergic neutrons: neural chemical that results in a pleasurable feeling
Detection in reinforcement
Depends on physiological state of organism. Will the reinforcer dectually be of any pleasure to the organism?
Is the reinforcer food and they are already full?
Where is the pre-frontal cortex?
Right behind the forehead
Where is the hippocampus
Buried deep in the brain
When first learning is the hippocampus or prefrontal cortex more active?
Hippocampus (activity is high at first and then decreases)
Prefrontal cortex activity in relation to learning
Activity in prefrontal cortex is low as learning first occurs and then it increases over time
Episodic memory
Memory of a collection of perceptions of events organized in time identified by a particular context
Ex. Memory of having birthday dinner with a friend
Semantic memory
Memory of facts and general information
Ex. Who the president is
Spatial memory
Example: remembering how to get from class to class
Where are place cells located
Hippocampus
What are place cells
Neutron that becomes active when the animal is in a particular location in the environment
Morris Water maze task:
Fats use environmental cues to orient themselves in space
There are variable and fixed start positions
If released from variable spots :relations/connections are made
If released from same position: rats will eventually find the platform through stimulus response learning.
At a constant start (stimulus response task): the rats with and without lesions will take the same amount of time
In a variable start (relational task): lesioned animals use no relations (take longer)
Water maze task lidocaine injection:
They questioned what happens if hippocampus vs. Cerebral cortex were inactivated on day 1 of training vs. 30 days after training
Results:
Hippocampus : day 1 injection then test = no memory. Day 30 injection then test = good memory
Cerebral cortex: day 1 injection then test = good memory. Day 30 injection then test = no memory
What is relational learning?
Putting the pieces together. “Relating things” to learn
Retrograde amnesia vs. Anterograde amnesia
Retrograde: can’t remember events prior to brain damage
Anterograde (what h.m had) can’t remember events that occur after brain damage
Is korsakoft’s syndrome a form of retrograde or anterograde amnesia?
Anterograde
Can be from chronic alcohol use
Milner 3 assumptions about h.m
- Hippocampus is not the location of long term memory
- Hippocampus is not the location of short term memory
- Hippocampus is involved in converting (consolidation) short term memories to long-term
Declarative memory (excplict)
Memory that can be verbally expressed (telling a story about a past experience)
Nondeclarative memory (implicht)
Does not depend on hippocampul formation
Motor memory, stimulus - response memory
