Limbic system Flashcards
What is the overreaching function of the limbic system?
Assign value to emotions or sensory events
How many layers is the hippocampal formation?
3
What are the 3 layers of the hippocampal formation?
- Dentate gyrus
- Hippocampus proper
- Subiculum
What is the name of the circuit that predates the modern concept of the limbic system?
Papez circuit
What is the papez circuit?
- Cinguate gyrus
- Hippocampus
- Fornix
- Hypothalamus - Mamillary bodies
- Thalamus
- Cortex
What is the function of the hippocampal formation?
- Formation of new memories and learning
What results from removal of the hippocampal formation?
Anterograde amnesia
What is anterograde amnesia?
Profound loss of recent or short-term memory and the ability to learn
What is retrograde amnesia?
Loss of memories from before the date of injury
Where is the amygdaloid nucleus located?
Deep to the uncus
What is the major afferent modality to the amygdaloid?
Smell
What is the major function of the amygdaloid?
- Programs appropriate behavioral/ emotional responses
- Puts affective value on stimuli
What happened in animals when the amygdaloid was stimulated?
Became more aggressive
What happening in animals when the amygdala was removed?
- Indifferent to stimuli that would have caused fear or sexual responses
What are the 3 functions of the central nuclei of the amygdala?
- Mediate emotional response
- Regulate autonomic nervous system
- Shape responses to emotional stimuli