1 / 22

Neural Communication

Neural Communication. Will Explain Why We FEEL……. Nervous. Strong. Sick. Pain. It all Starts with the Neuron 42-44. What are neurons?. Nerve cells (smallest unit of Nervous System) Billions/Cells do not regenerate but can adapt Conduct impulses that carry signals Types Sensory

dotty
Download Presentation

Neural Communication

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Neural Communication

  2. Will Explain Why We FEEL…… Nervous Strong Sick Pain

  3. It all Starts with the Neuron 42-44

  4. What are neurons? • Nerve cells (smallest unit of Nervous System) • Billions/Cells do not regenerate but can adapt • Conduct impulses that carry signals • Types • Sensory • Respond to incoming stimuli • Transmit information from senses to brain • Motor • Relay information from the brain to rest of the body • Interneurons • Process information between sensory and motor

  5. What are the parts of a neuron? • Cell Body • Life support center • Dendrites • Receive messages from other cells (INPUT) • Axons • Passes messages away from the cell body to other neurons (OUTPUT) • Myelin Sheath • covers the axons and helps speed neural impulses • Terminal Branches • Ends of axons; contain neurotransmitters • Synaptic Gap • Space between terminal branches and dendrites

  6. Neuron: Internally: message electrical. Externally: message chemical

  7. How are messages sent? Neurons do NOT touch each other – space b/w = synapse

  8. How are messages sent? • Neuron fires (action potential) through the synapses b/w neurons • In the form of a neurotransmitter • Process is electrochemical

  9. The All-or None Response • The idea that either the neuron fires or it doesn’t- no part way firing. • Like a gun

  10. Steps of Action Potential • Electrically charged atoms that stimulate neuron = ions • Interior of resting neuron = negative ions • Exterior of resting neuron = positive ions • Start of action potential comes from depolarization = positive ions let in

  11. Steps of an Action Potential • Ions enter the receiving neuron = exciting or inhibiting • Excitatory signals = pushing neuron’s accelerator • Inhibitory signals = pushing neuron’s brake • Threshold = Excitatory minus Inhibitory signals. If more excitatory, neuron will “fire” • toilet flush analogy

  12. How are messages sent? Refresh • Depolarization • Semipermeable cell membrane lets positively charged ions in. • Action Potential • If excitatory signals minus inhibitory signals exceed threshold • “all-or-none” response: neurons either fire or don’t • Release of Neurotransmitter • Cross synaptic gap and bind to receptors on receiving neuron • Refractory Period • Positively charged ions are pumped back outside; then neuron can fire again.

  13. TRANSITION SLIDE

  14. How do neurotransmitters influence us? P. 44-47 Chemical messengers released by terminal buttons through the synapse (over 60, you need to know 4). • Particular neurotransmitters have particular effects on behavior and emotions • Particular brain pathways use particular neurotransmitters • Examples: • Acetylcholine and memory • Dopamine and mobility • Serotonin and depression • Endorphins and pain

  15. Acetylcholine & Memory • Its function is motor movement and memory. • Lack of is linked to Alzheimer’s • When it’s released, muscles contract Botulin blocks transmission of Ach = paralysis

  16. Dopamine & mobility • Its function is motor movement and alertness. Lack of dopamine (death of nerve cells) is associated with Parkinson’s disease. Overabundance is associated with schizophrenia.

  17. Serotonin & depression • Function deals with mood control. Lack of serotonin has been linked to depression.

  18. Endorphins & Pain • Function - deals with pain control. • Natural opiates “runners high” • Response to pain & vigorous exercise We become addicted to endorphin causing feelings.

  19. How do drugs influence neurotransmitters? • 1. Block reuptake • … of neurotransmitter at pre-synaptic neuron  overabundance 0f neurotransmitter • Examples: Prozac = serotonin, cocaine = dopamine • 2. Mimic neurotransmitters- similar enough to occupy receptor site • Called agonists • morphine mimics endorphins • THC (in marijuana) & nicotine mimic dopamine • 3. Block receptor site – not similar enough to stimulate the receptor • Called Antagonist • Prevent neurotransmitter message from being relayed • Example: curare poison, Ach (no muscle contraction) • Essentially stop producing own natural opiates/endorphins • Always need a fix, dependency, more, unpleasant feelings

  20. Agonists and Antagonists

More Related