Unit 1

• B is ventral to C

  
• C is dorsal to B

  
• D is dorsal to E

  
• E is ventral to D

  
• E is dorsal to F

  
• F is ventral to E

  
• A is rostral to D

  
• D is caudal to A

  
• A is rostral to B

  
• B is caudal to A

  
• G is anterior to H

  
• A is anterior to H

  
• H is dorsal to E

  
• E is ventral to H

  
• J is lateral to H

  
• H is medial to J

  
• J is lateral to E

  
• E is medial to J

  
• cerebellum is dorsal to the brainstem
• Fundamental approaches to investigating the connection between structure and function

  • record neural activity
  • manipulate neural activity
  • lesion studies
  • computational studies
  • comparative studies
• Central nervous system (CNS) contains the brain and the spinal cord
• The peripheral nervous system contains the nerves and the ganglion
• Autonomic nervous systems contains the parasympathetic and the sympathetic system
• The parasympathetic system is the rest and digest system.
• Function of parasympathetic system: constricts pupils, increase saliva production, reduce heart rate, constrict bronchia, stimulates activity of digestive organs, pancreas and gallbladder, constrict urinary bladder, and stimulates the erection of genitals
• Sympathetic system is the fight or flight response
• Function of the sympathetic system:

  dilates pupils, inhibits saliva production, dilates bronchia, increase heart rate, inhibits activity of digestive organs and pancreas, stimulates the adrenal medulla to release adrenaline and noradrenaline, relaxes the urinary bladder, stimulates orgasm int he genitals
• Knee-Jern Reflex Circuit

  1. sensory neuron detects stimulation
  2. sensory neuron stimulates a motor neuron innervating quadriceps muscle
  3. At the same time, sensory neuron stimulates interneuron, which inhibits the motor neuron innervating the hamstring muscle
  4. Quadriceps contracts, hamstring relaxes, which results of the knee jerk
• Sensory neurons are afferent neurons and they perform signal transduction, which means they convert stimuli into a change of membrane potential
• Motor neurons are efferent neurons that innervate a muscle or gland
• Interneuron are every other neuron in the body
• Excitatory neurons excite/activate the postsynaptic neuron.
• Inhibitory neurons inhibit the postsynaptic neuron
• Feed-forward excitation is when one neuron synapses and depolarizes the next neuron.
• Diverging is when a neuron synapses into multiple different neuons
• Converging (integration) is when multiple neurons synapse onto one neuron. An example of this is that many inputs are required to activate a motor neuron.
• Feedback excitation is when the presynaptic neuron excites a postsynaptic neurons and that neuron excites the presynaptic neurons so its going in a loop
• Feed-forward inhibition is when a presynaptic neuron inhibits a postsynaptic neuron
• Feedback inhibition is when a presynaptic neuron excites a postsynaptic neuron and the postsynaptic neuron inhibits the presynaptic neuron. However, the downstream neuron will experience moderate excitation
• Cross inhibition is when two excitatory pathways cross-inhibit each other, only one can be activated at the same time