Unit 2 | Biological Bases of Behavior

• Neuron


  A nerve cell; the basic building block of the nervous system
• Agonist


  A molecule that, by binding to a reception sight, stimulates a response
• Antagonist


  A molecule that, by binding to a receptor site, inhibits or blocks a response
• All-Or-None principle


  A neuron's reaction of either firing (with a full-strength response) or not firing
• Neurotransmitters

  Chemical messengers that cross the synaptic gaps between neurons.

  • Released by the sending neuron, travel across synapse, and bind to receptors sites on receiving neuron.
  • Influence the neural impulse
• Nervous System


  The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous system.
• Amygdala


  Two lima-bean sized neural clusters in the limbic system; linked to emotion
• Hypothalamus


  A neural structure lying below the thalamus; directs maintenance activities (eating, drinking, body temperature)

  • Governs endocrine system through pituitary gland
  • Linked to emotion and reward
• Medulla


  The base of the brain stem; controls heartbeat and breathing.
• Cerebellum


  The "little brain" at the rear of the brain stem

  • processes sensory input
  • coordinates movement output and balance
  • enables non-verbal learning and memory
• Frontal Lobes


  Portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements