Neural communication
1 / 22

Neural Communication - PowerPoint PPT Presentation

  • Uploaded on

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

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Neural Communication' - dotty

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Neural communication

Will Explain Why We FEEL……





What are neurons
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

What are the parts of a neuron
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

How are messages sent
How are messages sent? chemical

Neurons do NOT touch each other – space b/w = synapse

How are messages sent1
How are messages sent? chemical

  • Neuron fires (action potential) through the synapses b/w neurons

  • In the form of a neurotransmitter

  • Process is electrochemical

The all or none response
The All-or None Response chemical

  • The idea that either the neuron fires or it doesn’t- no part way firing.

  • Like a gun

Steps of action potential
Steps of Action Potential chemical

  • 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

Steps of an action potential
Steps of an Action Potential chemical

  • 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

How are messages sent refresh
How are messages sent? Refresh chemical

  • 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.

How do neurotransmitters influence us p 44 47
How do neurotransmitters influence us? P. 44-47 chemical

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

Acetylcholine memory
Acetylcholine chemical & 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

Dopamine mobility
Dopamine chemical & 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.

Serotonin depression
Serotonin chemical & depression

  • Function deals with mood control.

Lack of serotonin has been linked to depression.

Endorphins pain
Endorphins chemical & Pain

  • Function - deals with pain control.

  • Natural opiates “runners high”

  • Response to pain & vigorous exercise

We become addicted to endorphin causing feelings.

How do drugs influence neurotransmitters
How do drugs influence neurotransmitters? chemical

  • 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