Learning, Memory and Behaviour Flashcards
What are the two types of memory?
Long term memory and short term memory
What are the two types of long term memory?
Explicit/Declarative and Implicit/Non-Declarative
What are the two types of explicit memory?
Episodic and Semantic
What are the four types of implicit memory?
Procedural
Priming
Classical conditioning
Non-associative learning
Where are explicit memories stored?
Diencephalon (thalamus and hypothalamus) and medial temporal lobe
Where are procedural memories stored?
Striatum
Where are priming memories stored?
Neocortex
Where are classical conditioning memories stored?
Amygdala and cerebellum
Where are non-associative memories stored?
Reflex pathways
What are episodic memories?
Memories of specific episodes in the past
Described as autobiographical
e.g. wedding day
What are semantic memories?
Factual knowledge
Derive from episodic memories
e.g. I know that the sky is blue from all my episodic experience of the sky being blue
What are procedural memories?
How to use objects
Movements of the body
e.g. how to play the piano
What are priming memories?
Exposure to a stimulus influences the response to another stimulus
e.g. seeing the word yellow makes you quicker to recognise the word banana
What are the two types of non-associative learning and what do they mean?
Sensitisation - response to a stimulus increases
Habituation - response to a stimulus decreases
What is the main feature of non-associative learning?
There is no reinforcement - no reward or punishment for the behaviour
Where is the hippocampus located?
Medial temporal lobe
Folding of what structure forms the hippocampus?
Infolding of the inferomedial part of the temporal lobe into the lateral ventricle
How do the two hippocampi communicate?
Hippocampal commissure
What is the purpose of the cortico-hippocampal circuit?
Information flow between the hippocampus and cortex
What is the order of information flow in the cortico-hippocampal circuit?
Hippocampus Entorhinal cortex Parahippocampal cortices Association cortices 1st sensory cortices
Information from the hippocampus and entorhinal cortex can also go directly to the association cortices
What are the functions of the parahippocampal cortex?
Site of convergence for cortical input, parahippocampal gyrus sends to the hipopcampus
Also recieves information outgoing from hippocampus
What procedure was Henry Molaison given in 1975 and why was it given?
Bilateral medial temporal lobe lobectomy
Given to control severe epilepsy
What was the result of the procedure given to Henry Molaison?
Anterograde amnesaia - could not form new memories.
Long term memories still intact, and could still hold a short conversation.
What procedure can be used on rodents to test spatial memory?
Morris Water Maze
Explain the procedure of the Morris Water Maze experiment?
Relies on rats desire to get out of water/dangerous situation
Rat placed in wading pool with hidden platform
Learns where platform is over 7 days
Platform removed, amount of time spent in correct quadrant of wading pool measured
Lesions to the hippocampus impair which type of memory?
Spatial memory
What does pharmacological inactivation of the CA1 region of hippocampus do?
Blocks retrieval of spatial memory
Rats spend less time in the correct quadrant
Name a drug that can be used to temporarily inactivate a region of the brain
Muscimol - GABAa agonist
What are the effects of blocking hippocampal NMDA receptors?
No LTP, blocks formation of spatial memory
What are Place cells?
Hippocampal pyramidal cells
Fire in complex bursts when an animal moves through a specific location
Region in which cell fires most is called the firing-field
Different locations encoded by different cells
Ensemble of neurons provides cognitive map
Give 5 pieces of evidence that support the fact that the hippocampus is involved in spatial memory
- Lesions to hippocampus reduce time spent in correct quadrant in Water Morris Maze
- Purfusion of the CA1 area of the hippocampus with Muscimol reduces time spent in correct quadrant
- Blocking hippocampal NMDA receptors blocks formation of spatial memory
- Place cells
- Taxi drivers size of hippocampus correlates with years of experience. Bus drivers do not
How can visual recognition memory be tested?
Novel Object Recognition Test
What is the procedure of the Novel Object Recognition Test?
A rat is presented with two identical objects and given time to explore them
One object is changed
The amount of time the rat spends exploring each object is measured
Rats normally spend more time exploring the new object
How are the results of the novel object recognition test presented?
As a discrimination ratio
Nov = time spent exploring novel object
Fam = time spent exploring familiar object
D = (Nov-Fam)/(Nov+Fam)
If D = 0, time spent exploring each object is the same
If D>1, time spent exploring novel object is longer
Real result was D = 0.48
What effect does lesions to the perirhinal cortex have?
Abolished novel object preference
Where is the perirhinal cortex located?
Adjacent to the hippocampus, highly connected to
How can object preference be used to test spatial memory?
Instead of replacing one object, one object is moved to a new location
Lesions to hippocampus disrupt longer exploration time of object in new location
