Chapter 6 - Lecture Flashcards
define taste aversion learning
after becoming sick due to a food item, the item itself becomes a warning stimulus for sickness
what are the conditioning explanations for taste aversions?
- laws of classical conditioning
- law of effect
what are the problems with classical conditioning (CC) explanations for taste aversion?
- one-trial acquisition (OTA) of taste aversion
- delayed conditioning of taste aversion (become sick later but still connect the cause)
- selectivity in taste aversion learning (more likely to stay away from something like a salad if you went to a buffet and decide the cause)
contrast the # of associations required for classical conditioning vs one trial learning
CC
- responses take a number of associations
eg. multiple pairings of the bell & food for Pavlov’s dog
OTL (one slide ota)
- a change in behaviour occurs after one association
contrast the time lapse between CS & CR in CC AND OTL
CC
- almost immediate
OTL
- often a large time lapse
contrast the extinction between CS and OTL
CC
- can be extinguished relatively easily
OTL
- highly resistant, response is powerful
contrast the generalisation, between cs and otl
CC
- cs can be easily generalised to other stimuli
OTL
- unlikely to be generalised
describe the Rescoria-Wagner Model
- rats in group B first learn an association between noise (CS) and shock (US)
- they later fail to learn the association between light and shock due to the associative strength that has been used up by noise-shock pairing
*also called blocking? can use this example to show exceptions to rule
describe the pretraining, conditioning, testing and response examples for blocking
A group (control): pretraining (none), conditioning (noise+light+shock), testing (light), response (freezing -high fear)
B group (blocking): pretraining (noise>shock), conditioning (noise+light+shock), testing (light), response (bar pressing - no fear)
what does the cerebral cortex do?
sensation, language, speech, thinking and motor activity
what does the thalamus do?
relay center for sensory information
what does the hypothalamus do?
regulation of endocrine gland activity relating to growth, sexual behaviour and other functions
what does the pituitary do?
growth: regulation of other endocrine gland acticity
what does the amygdala do?
emotion, aggression, memory
what does the hippocampus do?
learning and memory
what does the cerebellum do?
control of rapid and habitual movements, coordination of motor activity, balance
what does the brain stem do
physiological functions such as breathing, heart functioning, digestion
what does the reticular formation do?
arousal center, sleep-wake control
describe the hindbrain
- the lower brain stem responsible for basic physiological functions such as respiration and hr
- the cerebellum is centrally involved in locomotion and balance
describe the midbrain
- the upper brain stem responsible for regulating waking and sleeping adn for controlling general arousal
- nerve fibers associated with movement
describe the forebrain
- the largest and most complex brain structure
- its most important structures include the hypothalamus, the thalamus, and other structures of the limbic system, as well as the cerebrum and cerebral cortex *limbic system important in emotional learning
learning can take at least 4 basic forms:
perceptual learning, stimulus-response learning, motor learning, relational learning
describe perceptual learning
- involves learning to recognize things, not what to do when they are present
- can involve learning to recognize entirely new stimuli, or it can involve learning to recognize changes or variations in familiar stimuli
describe the streams involved in perceptual learning
The ventral stream
- Object recognition, continues ventrally into the
inferior temporal cortex
(WHAT the person is looking at)
The dorsal stream
- Perception of the location of objects, continues
dorsally into the posterior parietal cortex (WHERE item is in the environment)
*perceptual learning is happening everywhere in the brain and vision is everywhere in the brain
describe stimulus-response learning
Learning to automatically make a particular response in the presence of a particular stimulus
* Stimulus–response learning is the ability to learn to perform a particular behaviour when a particular stimulus is present
* Involves the establishment of connections between circuits involved in perception and those involved in movement
recall classical conditioning in terms of stimuli/responses
before conditioning: bell> no response
food (us)> salivation (ur)
during conditioning: bell (cs) followed by food (us)>ur (salivation)
after conditioning: bell (cs)> salivation (cr)
describe the hebb rule (neural model of classical conditioning)
Hebb Rule: If a synapse repeatedly becomes active at about the same time that the postsynaptic
neuron fires, changes will take place in the structure + chemistry of the synapse that strengthen it
describe the neural model of classical conditioning
- somatosensory neuron collecting info from senses, results in a motor response (blinking output)
- neuron in auditory system weakly connected to blinking output but becomes active as the postsynaptic neuron fires + connection is strengthened
describe the neural model for instrumental conditioning: a simple model for motor learning
stimulus>neural circuit that detects a particular stimulus>neural circuit that controls a particular behaviour>behaviour>reinforcing stimulus (eg. food)>reinforcement system>neural circuit that controls …etc.
define relational learning
Relational Learning establishes neuronal
connections in systems that include memories that
can be verbally expressed, such as memory for
events in a person’s past (i.e., declarative memory)
and memory whose formation does not depend on the hippocampal formation
- A collective term for perceptual, stimulus-response, and motor memory (i.e., non declarative memory).
what is the hippocampal formation?
- A forebrain structure of the temporal lobe, constituting an important part of the limbic system
- Temporal Lobe
- Characteristic appearance
describe long-term potentiation
Long-term potentiation (LTP) is a persistent strengthening of the synapses, or connections, between neurons
- It is one of the fundamental mechanisms that underlie learning and memory
- LTP occurs when two neurons are activated at the same time, and it results in an increased ability of the postsynaptic neuron to transmit signals from the presynaptic neuron
describe the appearance/structure of the hippocampal formation
axon in perforant path is always found in the same location
- connects to neuron in the dentate gyrus
how can we measure charge in the hippocampal formation?
- can measure and cause electrical changes
- take electrode, stimulate axons in perforant path and record from dentate gyrus (recording changes in second neuron,what happens to the electrical charge?)
how can long-term potentiation be applied to learning?
when you are thinking about a concept, activating specific circuits and then testing memory
- the fact that you’ve studied that = takes less time to bring up the info
*if a neuron has been stimulated enough, in the future it doesn’t need a lot of stimulation to be active again
how does amplitude relate to long term potentiation? *not on slides
referring to change that is happening in the charge
- if the amplitude is fairly high, neuron doesn’t need much stimulation to be put into action
describe EPSP (long term potentiation)
An Excitatory Postsynaptic Potential (EPSP) is a temporary change in
the electric potential of the membrane of a postsynaptic neuron (the
neuron that receives signals) that makes it more likely to generate an
action potential
- EPSPs are a result of the activation of excitatory synapses, which transmit signals from presynaptic neurons to postsynaptic neurons
describe the excitatory nature of EPSPs
EPSPs are excitatory in nature, meaning
that they increase the likelihood of the postsynaptic neuron
firing an action potential
describe associative long-term potentiation
- take a weak stimulus (ex. sound/bell) and strong stimulus (puff of air), if you activate at thesame time adn record EPSPs, because both have been stimulated together, the weak stimuli become stronger
= learning takes place
*learning can take the form of increased activity but also _
decreased activity (not in slides)
describe long-term depression
Low-frequency stimulation of the synaptic inputs
* Long-term depression (LTD) is a phenomenon
that is the opposite of long-term potentiation
(LTP)
* While LTP involves the strengthening of synaptic
connections, LTD involves the weakening or long-
lasting decrease in the strength of synaptic
connections between neurons
*when synapses not activated, become weaker
ex. when not paying attention to concept, have to spend more time jogging memory for test
define retrograde amnesia
cannot remember events prior to brain damage
define anterograde amnesia
cannot later remember events that occur after brain damage
*how is alcohol use related to amnesia?
- can result in experience of retrograde amnesia with heavy use
- can result in cell death
- can result in memory issues
what did the H.M. story tell us?
The hippcampus is not the location of long-
term memories
2. The hippocampus is involved in converting
immediate (short-term) memories into long-
term memories
describe the examples of broken drawings shown in class
- as each set progresses, the drawings become less broken
- for most participants, when they have encountered the stimuli before, they are able to identify each item very quickly
- also happened to H.M.
- if h.m. saw elephant in umbrella and went back to set 1 in later trials, would be able to identify correctly (but wouldn’t be able to say why he could do it)
*we have diff kinds of memory
define declarative memory (explicit)
Memory that can be verbally expressed, such as
memory for events in a person’s past
define nondeclarative memory (implicit)
Memory whose formation does not depend on
the hippocampal formation; a collective term for perceptual, stimulus–response, and motor memory
ex. the drawing identification task isa good example
in the graphs on the ventromedial prefrontal cortex and hippocampus, what was on the y and x axis?
x axis: time (days)
y axis: relative activity
what do the graphs on the ventromedial prefrontal cortex and hippocampus show?
- hippocampus deals with immediate handling of info and long term storage happens in the ventromedial cortex
- hippocampus activity is increased at the beginning and it decreases over time
- activity in the ventromedial cortex increases over time
recalling information in the same order would be the responsibility of the_
hippocampus (not on slides)
describe the simple model of the learning process
sensory information> short-term memory > long-term memory
long-term memory can go to short-term memory
moving from short-term memory to long-term memory is called
consolidation
- has to do with putting things in context: how do you give it meaning?
moving from long-term memory to short-term memory is called
rehearsal
-there has to be a certain amount of rehearsal but repeating it won’t necessarily bring theinfo up in the way you want to use it
