Limbic system/Memory
What anatomical structures are generally included in the limbic system? What are their functions?
Thalamus: relay center of brain, decides which sensory inputs go where
Hypothalamus:maintains homeostasis, regulates sleep/wake cycle, body temp and hunger
Amygdala: fear, anxiety, aggression, sexual attraction, pleasure
Hippocampus: learning and memory, converting short term memory to long term memory
What are examples of implicit and explicit memories?
Implicit: harder to tell people, it is more of an experience
- Emotional and procedural memories
Explicit: able to use it, easily to explain, facts, figures, events
- Semantic and Episodic memory
What is orienting attention? Give example.
Locating specific stimuli out of many stimuli
Ex. finding your friend in a crowd at the bar
What would be the result of sympathetic activation of the: heart, lungs, skin, pupils, blood vessels, GI tract, bladder?
Sympathetic fight or flight response:
increased HR, dilation of airways, sweat glands, pupillary dilation, dilation of blood vessels in skeletal muscle, constriction of blood vessels in gut
If lesion in amygdala: less fear, hypersexual and mellow (Kleuver Bucey Syndrome)
If lesion in hippocampus: can't convert short term memories into long term memories
If lesion in hypothalamus: change in appetite, temp control, sleep and mood
If lesion in thalamus: loss of senses, decreased balance and coordination and pain related issues
What is Emotional and Procedural memory? Give examples
- Ex. the feeling of the first time you rode a bike
Procedural: the memory of how to perform a common task without actively thinking
- Ex. you can ride a bike automatically without thinking about it
What is divided attention? Give example
Attending to 2 or more stimuli
Ex. trying to drive and someone is in the passenger seat trying to talk to you
What would be the result of parasympathetic activation of the: heart, lungs, skin, pupils, blood vessels, GI tract, bladder?
Decreased heart rate, airway constriction, pupillary constriction, dilation of vessels in the gut and mucous membranes, gut motility (smooth muscle contraction), secretions in gut, saliva and mucous membranes, no parasympathetic innervation of skeletal muscle
What is the function of the Papez circuit?
Learning, memory and emotion
What is Semantic and Episodic memory?
Semantic: the memory of general knowledge and facts
- Ex. you know what a bicycle looks like from being shown a picture
Episodic: the memory of an event
- You remember falling off your bike one day when you were younger from hitting a curb
What is Selective attention? Give example
Attending to important stimuli and avoiding districation
Ex. avoiding what the person in the passenger seat is saying so you can focus on driving
For the Sympathetic division, which nerves are included, what are the pre and postganglionic axon lengths and general pathway and what are the neurotransmitters and receptor types at each synaptic site?
The first axon (pre) is short, the second axon (post) is longer
Nerves included: from T1-L2
Sympathetic transmitters: 1st synapse between pre and postganglionic neurons is Cholinergic nicotinic (Ach), 2nd synapse is between postganglionic neuron and effector is Noradrenergic (norepinephrine)
What are the structures and roles of each structure involved in memory?
Prefrontal cortex: working memory
Hippocampus: explicit memory formation
Cerebellum and basal nuclei: implicit memory (motor) formation
AMygdala: emotion-related memory formation
What can limit attention?
Limited by total attention available, ability to orient, divide, select, sustain and switch attention.
Can also be limited by amount of energy you have and interest in the task
What is sustained attention? Give example.
Continued activity over time
Ex. Really focused on studying over a period of time
For the Parasympathetic division, which nerves are included, what are the pre and postganglionic axon lengths and general pathway and what are the neurotransmitters and receptor types at each synaptic site?
Nerves: derived from fibers from CN 3,7,9,10 and sacral cord S2,3,4
Preganglionic neuron is long (CNS), Postganglionic neuron is shorter
Neurotransmitters: 1st synapse (ganglionic) is cholinergic (nicotinic)- Ach, Synapse into effector is also cholinergic (muscarinic)- also Ach
What is the basic memory pathway?
Incoming information--> sensory buffers--> encoding--> short term storage
--> working memory--> Performance
OR
--> Consolidation--> Long Term Storage--> Retrieval--> working memory--> Performance
What are the 5 types of different attentions?
Orienting, Divided, Selective, Sustained, Switching
What is switching attention? Give example.
Changing tasks
Ex. switching back and forth between listening to your friend talk and driving
Identify the Limbic system structures in a cross-sectional view
LOOK AT PICTURE