What does cognition relate to?
Highest order of brain function
Behaviour that deals with thought processing
What is cognition?
Integration of all sensory systems to make sense of a situation
What is neuronal plasticity?
Ability of central neurones to adapt their neuronal connections in response to learning experiences
What is the function of most of the cerebrum?
Association areas which integrate areas from multiple sources
What is integration of information from multiple sources required for?
Cognition
What are parallel processing units?
Areas that integrate information from multiple sources
What are the 3 components of learning and memory?
Hippocampus
Cortex
Thalaus
What is the hippocampus used for in learning and memory?
Formation of memories
What is the cortex used for in learning and memory?
Storage of memories
What is the thalamus used for in learning and memory?
Searches and accesses memories
Where are memories formed?
Hippocampus in limbic system
What is the function of the limbic system in formation of memories?
Gives memories emotional significance
What are the areas of the limbic system?
Hypothalamus
Hippocampus
Cingulate gyrus
Amygdala
What is the hypothalamus associated with?
ANS responses
What is the hippocampus associated with?
Memory
What is the cingulate gyrus associated with?
Emotion
What is the amygdala associated with?
Memory
What is the limbic system collectively responsible for?
Instinctive behaviour
Emotive behaviour
What is emotive behaviour driven by?
Reward and punishment
What does electrically stimulating the reward areas of the limbic system result in?
Feeling of euphoria
Why are reward and punishment essential to learning?
Give task significance
Form affective components of sensory experiences
What does bilateral hippocampal damage cause?
Have immediate and very long term memory, but are unable to form short or long term memories
Retained reflexive memory
What can memory be divided into?
Immediate
Short term
Intermediate long term
Long term
How long do immediate memories last for?
A few seconds
How quickly do visual and auditory memories decay?
Visual= 1 second Auditory= 4 seconds
How long does short term memory last for?
Seconds to hours
What is short term memory used for?
Short term tasks e.g. dialling phone number, mental arithmetic, reading a sentence
What does short term memory rely on?
Excitation from reverberating circuits
What causes short term memories to become long term memories?
Excitation of reverberating circuits causing consolidation
Determination of significance
What happens if a short term memory is deemed insignificant?
Reverberations fade and no consolidation occurs
What is amnesia?
Memory loss resulting from disrupted reverberation
What are the types of amnesia?
Anterograde
Retrograde
What is anterograde amnesia?
Unabe to recall events that happen after the injury
Can be short lived or permanent
What is retrograde amnesia?
Can’t remember events leading up to injury, but usually retain long term, memories
What causes retrograde amnesia?
Thalamus damage
How long does intermediate long term memory last?
Hours to weeks
What causes short term memories to develop into intermediate long term memories?
Chemical adaption at the presynaptic terminal, increasing Ca++ entry to terminals and increased neurotransmitter release
What is long term memory associated with?
Structural changes in synaptic connections
What are the structural changes in synaptic connections that take place in long term memory?
Increase in neurotransmitter release sites on presynaptic terminals
Increased number of neurotransmitter vesicles
Increase in no of presynaptic terminals
What is long term potentiation?
Increased amplitude in graded membrane potential in post synaptic cell
What is the function of long term potentiation?
Strengthens synapse
What is episodic memory?
Abstract memory for events
What is semantic memory?
Memory for words, rules and language
What is explicit memory>
Episodic and semantic memory
Based in hippocampus
What is implicit memory?
Memory slowly acquired through repetition
Mainly in cerebellum
What is the function of consolidation?
Convert short term to long term memory
What does consolidation involve?
Selective strengthening of synaptic connections through repetition
What is the Papez circuit?
Hippocampus, maxillary bodies, anterior thalamus, cingulate gyrus
What is the function of the Papez circuit in consolidation?
Reverberating continues through the Papez circuit, frontal cortex and sensory and association areas until consolidation is complete
What is the association of the frontal cortex and Papez circuit?
Frontal cortex gates Papez circuit
What is the function of coding?
New memories stored alongside other existing memories that the brain deems similar
What type of sleep is important for memory?
REM sleep
What is the function of dreaming in memory?
Enable memory consolidation and reinforce weak circuits