Chapt. 19 - Instrumental Learning Flashcards
Define habit strength
the strength of the association between a stimulus and a response which is reinforced by pairings between a stimulus and response which causes habit strength to increase.
also known as associative strength
Generally, what did Divac believe the function of the dorsal striatum was
believed it integrated/combined functions of motor, sensory, and cognitive control therefore giving rise to both cognitive deficits and complex motor disturbances when disconnected/impaired.
believed intermediate processing station
Define stimulus-response habits
behavior or sequences of behavior that are repeated and result in some kind of reinforcement
How is driving and keypads an example of stimulus-response habits
Driving - Same drive to work, the repeated stimulus takes over and switches away from the high order system of learning that is used when something new/unfamiliar is learned. The dorsal lateral system takes over because no longer learning it.
Keypad - doesn’t actually remember password after doing it so many times, your hands just move without thinking. Lost cognitive control and awareness. Dorsal lateral once again takes over.
What kind of information does the dorsolateral striatum receive
extensive polymodal sensory information representing the external world. Is well informed about world at any given time. sensory, olfactory, visual info, etc.
(similar to hippocampus and memory)
What kind of organization does the dorsal lateral striatum have
topographical organization - each type of information projects to a SPECIFIC location and doesn’t distribute information as much (different than hippocampus)
What information did LASHLEY provide in regards to patterning of learned activities
That the basal ganglia is not essential for this activity
What is the anatomy (what info is received) of the dorsal lateral striatum
receives information about limb and whole-body movements. Motor projections dump into striatum, info about movements at any given moment
Explain the electrophysiology of the dorsal lateral striatum
Neurons display evoked responses to sensory cues and motor response.
stimulus-response association is set up nicely because sensory and motor information are both occurring at the same time
also get dopamine projections/release info. Released when reinforcement builds up habit/associative strength
Specifically, when do neurons in the striatum display sensory evoked responses
when a sensory stimulus is linked with a conditioned movement
What experiment supports electrophysiology of the dorsal lateral striatum
Mouse noses facing forward, on sensory to start. A tone is played to the right, then mouse turns face and initiates those sensors. (visual/sensory stimuli occurs which then links to a conditioned movement of the head turn which creates electrophysiology response results
What are the 4 types of experiments used to support behaviour
- visual/tactile guided maze learning
- egocentric maze learning
- conditional discriminations (operant chamber)
(profs fav) - skilled reaching and cued versions of the water task
8 arm radial maze experiment (with lights)
2 groups of rats:
1. received neurotoxic lesions of dorso-lateral striatum
2. received vehicle injections (same process but no lesions)
targeted the neurons and not fibers because fibers would dissociate system and we need those intact to keep synapses
one week recovery period. trained on 8-arm radial maze
Changes daily, remains same for the day. 4 arms randomly selected to have lights and reinforced when go to those ones
Results of 8 arm radial maze
once they learn the pattern/habits, hard to break out of them. The control had high accuracy by the end. Impaired was not as successful because habit like process
Another 8-radial arm maze and results
Same groups 1. control 2. striatal, medial and lateral damage group
No matter where rats start, always have to turn same direction
Results - could not learn that turning means reward
Skilled reaching experiment
Start form back of clear rectangular box. Little opening at the end, with a piece of food in reach. Animal must paw to reach food, grab it, and eat it. Then go back again and repeat.
Groups: 1. neurotoic lesions of dorsolateral 2. dorsomedial 3. vehicle injections (control)
then recovered and trained on this task
Results of skilled reaching experiment
measured on single success (absolute complete success on first try) and total success measure (eventually get it, not as good).
Operant chamber experiment
multiple different combinations to get food. ex. tones-press lever-food or light-chain-food
requires individuals to use stimulus response (instead of stimulus-outcome or response-outcome associations) provides great isolation!
Operant chamber experiment results
control shows great accusation curve
impaired does not, goes up and down, all over the place