Lecture 17: Learning and Memory ll Flashcards
unconscious memory is also known as
implicit or nondeclarative memory
unconscious memory
Memory that influences behaviour in an automatic, involuntary way. Relates to automatic adjustments to perceptual, cognitive, and motor systems that occur beneath the level of conscious awareness
types of unconscious memory
procedural, perceptual, and stimulus-response memories
procedural memory example
how to ride a bike
perceptual memory example
how to unconsciously tell identical twins apart
stimulus-response memory example
salivating in response to a ton
conscious memory is also known as
explicit or declarative memory
types of conscious memory
episodic & semantic memory
episodic memory
personal experiences associated with a time and place. Autobiographical memory that involves contextual information and is learned all at once.
semantic memory
Encyclopedic memory of facts and general information, often acquired gradually over time. This knowledge need not be associated with the time or place in which we learned the information.
what type of memory is prompted by “show me”
unconscious memory
what type of memory is prompted by “tell me:”
conscious memory
what type of memory is associated with perceptual learning?
implicit memory
what type of memory is associated with motor/procedural learning?
implicit memory
what type of memory is associated with relational/stimulus-stimulus learning
explicit memory
What type of memory is associated with stimulus-response learning?
implicit and explicit memory
sensory memory
Allows an individual to retain the experiences of the sensation slightly longer than the original stimulus
what is another word for sensory memory?
perceptual memory
how long does sensory memory last?
a few seconds
how long does short-term memory last?
seconds to minutes
how much information enters short-term memory?
only a small fraction
memory capacity of short-term memory
The memory capacity of short-term memory is limited to a few items
The length of short-term memory can be extended through rehearsal.
long-term memory
Information that will be retained from short-term memory is consolidated into long-term memory. Long-term memories can be retrieved throughout a lifetime and strengthened with increased retrieval
how long does long-term memory last?
for long periods
perceptual learning
A pattern recognition system that allows us to recognize and identify objects or situation & recognize changes in familiar stimuli. type of unconscious, implicit learning
neurobiological mechanism behind perceptual learning
Involves changes in the strength of connections between primary neurons in the primary and association sensory cortexes
visual agnosia and memory
Damage to regions of the brain involved in visual perception not only impairs the ability to recognize visual stimuli but also disrupts people’s memory of visual properties of familiar stimuli
motor learning
Learning to make a sequence of coordinated movements
can motor learning be improved?
yes! We use feedback from our movements from our joints, vestibular system, eyes, ears, etc. to improve our movements
what parts of the brain are involved in motor learning?
The cerebellum, thalamus, basal ganglia, and motor cortex
what MUST be true for classical conditioning to occur?
We study this type of learning when the animal has no control over its environment
basic principle of classical conditioning
some stimuli trigger innate responses
US ->
UR
CS->
CR
unconditioned stimulus
a stimulus that has inherent value, like food or a painful shock
unconditioned response
a behavioural response that is largely innate
conditioned stimulus
a stimulus that was initially perceived as neutral but is now perceived as predicted of a US
conditioned response
a behavioural response that occurs in response to a CS. The behaviour is often similar to the UR that was elicited by the US during training.
what are other words for instrumental conditioning?
operant conditioning or reinforcement learning
basic principle of instrumental conditioning
we learn from the consequences of our actions
instrumental conditioning
The likelihood of you repeating an action depends on whether it was previously reinforced or punished.
neurobiological basis of instrumental conditioning
The process of reinforcement strengthens a connection between neural circuits involved in perception and those involved and those involved in movement
main difference between instrumental and classical conditioning
In contrast to Classical (Pavlovian) learning, operant conditioning requires that the animal can move and make decisions that influence their environment
reinforcement stimulus
Appetitive stimulus. When it follows a particular behaviour, it increases the likelihood the animal will repeat the behaviour.
punishing stimulus
Aversive stimulus. When it follows a particular behaviour, it decreases the likelihood the animal will repeat the behaviour.
two major pathways between the sensory association cortex and the motor association cortex
- direct transcortical connections
- the basal ganglia
direct transcortical connections path
connections from one area of the cerebral cortex to another. Involved in acquiring complex motor sequences that involve deliberation or instruction
the basal ganglia path is important for
habit formation
how does the basal ganglia path work?
integrates sensory and motor information from throughout the brain. As learned behaviours become automatic and routine, they are transferred to the basal ganglia
how are the cortical imputs to the basal ganglia regulated?
through dopamine signalling
what is the major input of the basal ganglia
the striatum, which consists of the caudate, putamen, and nucleus accumbens.
role of dopamine in the striatum
dopamine neurons in the midbrain (substantia nigra and ventral tegmental area) project to the striatum and seem to signal reinforcement and punishment
dopamine in the striatum is correlated to ___
motivation
effect of transient dopamine fluctuations on behaviour
drive learning by signalling how unexpectedly good or bad the current moment is
role of the basal ganglia in learning and memory
As the action and thought patterns are repeated, they become more habitual and ingrained. Across this transition, different circuits within the basal ganglia become involved in the action selection and action execution processes
lesions of the basal ganglia
disrupt reinforcement learning and habit learning but do not strongly affect perceptual learning or stimulus-stimulus learning
HM
Henry Molaison. he had a bilateral hippocampal lesion to treat his epilepsy, but he lost the ability to form explicit memories (severe anterograde amnesia). he also suffered from graded retrograde amnesia
Korsakoff’s syndrome
permanent anterograde amnesia caused by brain damage, usually resulting from chronic alcoholism. Korsokoff’s patients are unable to form new memories but can still remember old ones before the damage occurred
Confabulation
reporting of memories of events that did not take place without the intention to deceive. seen in people with Korsakoff’s syndrome
what happens to memory when people don’t have a functional hippocampus
Without a functional hippocampus, the brain cannot form new episodic or semantic memories. Their short-term, working memory is generally fine. They can also remember previously learned semantic information if it was consolidated before the hippocampal damage
role of hippocampus in memory
seems to be involved in converting short-term memories into explicit long-term memories. forms an index that can represent and reactivate the sensory systems that initially encoded any given event/experience.
The simplest model of memory process
sensory information enters short-term memory, rehearsal keeps it there, and eventually, the information makes its way into long-term memory where it is permanently stores
memory encoding (pattern storage)
cortical sensory systems -> hippocampus
memory retrieval (pattern completion)
partial cue -> hippocampus -> cortical sensory systems
hippocampal memory overtime
over time, memories become less depend on the hippocampus
hippocampal training theory
hippocampal activity is “training” the cortex, causing a reorganization of the synaptic weights in the cortex so that intra-cortical connections can support memory recall on their own.
hippocampal semantic memory theory
all memory starts off as episodic, which is dependent on the hippocampal nodes interacting in the cortex. Over time, as facts emerge from repeated episodic experiences, these semantic memories are permanently stored in the cortex in a hippocampus-independent manner
anterograde amnesia
the inability to learn new information or retain information after the brain injury. Memories from before remain intact
retrograde amnesia
the inability to remember events that occurred before the brain injury
complete amnesia is ___
rare
what type of amnesia results from hippocampal damage
anterograde amnesia
amnesic patients are capable of what types of learning
perceptual learning, motor learning, and stimulus-response learning
t-maze experiment
With minimal training, healthy mice often turn towards the place goal on the probe test. With overtraining, they turn toward the response goal
the t-maze experiment demonstrates what
that explicit spatial memory is what is initially learned but that a stimulus-response memory starts to dominate
what type of learning is affected by lesions in the basal ganglia
implicit response learning
what type of learning is affected by lesions in the hippocampus
explicit place learning
how is reinforcement signalled?
substantia nigra and ventral tegmental area
goal of instrumental conditioning
detect presence of reinforcing stimulus and strengthen the connections between the neurons that detect the specific stimulus and the neurons that produce the response
relational learning is the basis of ____
declarative memory (semantic and episodic)
