Steven Crane Compiled Section Handouts. Human Behavioral Biology 2012

Switch sub-units to change their efficacy or second-messenger systems

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  Many subunits makes for many types of combinations
  
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  Example: glucocorticoid action in the brain. Bind to same receptor, but the cofactor differs.
  
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    Hippocampus: cofactor causes GCs to cause less growth factor expression --> neuron atrophy
    
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    Amygdala: cofactor causes GC to cause more growth factor expression --> increased anxiety susceptibility.
    

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  Multiple binding sites
  

Limbic System

What are the three layers of the brain? How do they differ?

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  Hindbrain: reptilian brain taking care of basic physiology.
  

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  Ex: Odin's curse where you lose ability to breathe automatically
  
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  Partially controlled by higher limbic structures.
  

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  Midbrain: mamalian brain; limbic system; emotional brain
  
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  Forebrain: the cortex; our abstract associational level
  

^o Bidirectional communication with the limbic system

The Papez circuit and its myriad effects on the hypothalamus. Know the structures, their basic functions, and their connections!

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  Structures: Hypothalamus, amygdala, septum, hippocampus, mammilary bodies, thalamus, ventral tegmental area (VTA), nucleus accumbens, frontal cortex.
  
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  Connections: amygdalo-fugal pathway, fimbria fornix, medial forebrain bundle, mammilo-thalamic tract, stria terminalis, cortex-limbic connections
  
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  How does a structure go about having its strongest effect on the hypothalamus?
  

^o Whatever has the fewest synapses between it and the hyp.

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  Why is the stria terminalis so weird?
  

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  It's one LONG neuronal tract that loops around the hippocampus between the amygdala and the hyp.
  
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  Reflects the movement of brain regions during embryonic development and because brain evolution is one system duct-taped on top of another.
  

What are the subnuclei of the hypothalamus and what are their functions?

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