FNS 31 The Olfactory and Limbic Systems

  1. What do the mitral cells project to?
    • Anterior Olfactory Nucleus
    • Lateral Olfactory Stria to the primpary olfactory cortex & amygdala
  2. Components of the Olfactory Cortex
    • Pyriform lobe
    • Entorhinal Cortex
  3. What is Kallmann Syndrome?
    Association between a lack of sense of smell and decreased reproductive function (usually males)
  4. What are the major functions of the limbic system?
    • Emotion
    • Memory
    • Integration of sensory information with autonomic function
  5. Structures of the Limbic System
    • Cingulate, Subcallosal & Parahippocampal Gyri
    • Amygdala, Septal Nuclei, Basal Forebrain
    • Anterior Thalamus & Mammillary Bodies
  6. What are the structures in and functions of the Cingulate Cortex?
    • Cingulate, Subcallosal & Parahippocampal Gyri
    • Emotional negative experiences of chronic pain
    • Cognition and emotion: empathy, conflict resolution and decision making
  7. Subdivisions of the Hippocampus
    • Dentate Gyrus
    • Hippocampus Proper
    • Subiculum
  8. Dentate Gyrus: Function and layers
    • Input zone of hippocampus
    • Entorhinal cortex --> DG --> Hippocampus proper

    Layers: outer molecular layer, intermediate cell layer (granule), inner polymporphic layer
  9. Hippocampus Proper: Function and layers
    • Input from DG, entorhinal cortex, septum
    • Output into fornix to septum

    Layers: outer molecular layer, intermediate cell layer (pyramidal), inner polymorphic layer
  10. Subiculum: Function and associated structures
    • Major output zone of hippocampus
    • Axons form alveus --> fimbria --> fornix
  11. What is the major function of the Hippocampus?
    Conversion of short-term memories into long-term memories
  12. Anterograde amnesia
    • Deficits in acquisition of new memories
    • Often due to lesion affecting hippocampus
  13. Papez Circuit: Path and Function
    Cingulate cortex --> Hippocampus --> Mammillary Bodies --> Anterior Thalamus --> Cingulate cortex

    Control of emotional expression
  14. What is the fucntion of the Septum?
    Labels sensory stimuli as positive or pleasurable
  15. What symptoms would be expected from a lesion to the Septum?
    • Hyperemotional status
    • Impaired learning
    • Perseveration - repetition of incorrect response
  16. What are the major function of the Amygdala?
    • Focusing attention
    • Labels stimuli as negative or harmful
    • Fight or flight response
    • Aggressive responses
  17. Kluver-Bucy syndrome:
    1. Cause
    2. Symptoms
    • 1. Lesion to Amygdala
    • 2. Tamesness, hyperoral/hypersexual behavior, agnosia
  18. Agnosia
    Inability to recognize objects, people, etc. by sight
  19. Urbach-Wiethe Syndrome:
    1. Cause
    2. Symptoms
    • 1. Bilateral lesions of the amygdala
    • 2. No fear, difficulty reading other's emotions
  20. What is the role of the Nucleus Accumbens?
    Role in additction (drugs, alcohol, etc.)
  21. Basal Forebrain:
    1. Location
    2. Major component and related disease
    • 1. Ventral to anterior commissure
    • 2. Substantia Innominata - loss typical in Alzheimer's dementia
Card Set
FNS 31 The Olfactory and Limbic Systems
FNS 31 The Olfactory and Limbic Systems