Jill Botte Taylor

• Neurobiologist and got a stroke (gave a TedTalk on it)

• Are our thoughts who we are?

Nervous System Anatomy

• CNS (Central Nervous System)

  • Vital makesuit of the body

  • Brain and spinal cord

    • Main components of the control center

• PNS (Peripheral Nervous System)

  • Nerves and everything else that send out messages to breath and to walk

  • Somatic nervous system

    • Motor neurons (efferent)

      • Motor takes action after receiving the information from sensory

      • Efferent

        • Caries CNS info to muscles, glands, and organs to initiate action

    • Sensory neurons (afferent)

      • Sensory input takes in information

      • Afferent

        • Carries sensory info to the CNS for processing

    • S.A.M.E (Sensory Afferent Motor Efferent)

    • Stimulus/response

    • Exceptions

      • Processing disorders cause you to process things slowly and have a delay in the communication between the PNS and the brain

    • Reflexes

      • Testing your sensory and motor neurons

      • Monkey reflex - stoke the foot to see if it will straighten

      • Startle reflex

      • Knee reflex - hit kneecap to see if it responds

    • Interneurons connect motor and sensory neurons (interpret the signals from sensory)

  • Autonomic nervous

    • Can’t control much of it

    • Parasympathetic

      • Rest and digest system

      • Eyes are relatively constricted

      • Salivary glands are stimulated as you are eating

      • Slow heartbeat (sleeping, you have 50-60 beats per minute)

      • Bronchi are constricted (don’t need a lot of oxygen)

      • Liver stimulates bile (breaks food down) release

      • Peristalsis secretion in intestines

      • Contracts bladder

    • Sympathetic

      • Fight or flight response

      • Some of this is a critical instinct, but some of this becomes a learned behavior

      • Raising heartbeat

      • Short of breath

      • Sweaty palms

      • Dilated pupils (can see better in the dark)

      • Inhibited salivation

      • Bronchi dilated

      • Liver stimulates glucose release

      • Epinephrine and norepinephrine in intestines

      • Constipation, relaxed bladder

    • How does this look in humans?

      • Crying

      • Shouting

      • Singing

      • Humming

      • Screaming

Neurons

• Neurotransmitters - transmit messages

• Dendrites - receive messages

• Axon terminals - send out messages to another neuron

• Myelin sheath - grows over time, and the more mature a neural network is, the faster the signal travels

• Sensory

  • Pseudounipolar - nucleus is in the center

• Relay

  • Bipolar interneuron

• Motor

  • Multipolar

Salty Bananas

• NaCl and Potassium

Action Potential

• Electrical charge that travels through the neurons

• Will change polarization over and over again down the axon

• Sodium and Potassium are responsible for sending the electrical signals down the neurons

• Threshold

  • The value that the electrical charge it has to reach in order for the neuron to be fired

• Latency period

  • Can’t fire neurons

• All or nothing response

  • When the depolarizing current exceeds the threshold, a neuron will fire

  • If the threshold is not reached, it does not fire

• Intensity

  • Remains the same across the entire axon

• Demyelination

  • Signal isn’t protected, so it can’t function

  • Multiple sclerosis - attacks the myelin sheath and the cells that maintain the sheaths

  • Guillain-Barre Syndrome - sudden onset numbness, often a fully recoverable condition with treatment

  • Adrenoleukodystrophy (ALD) - destroys the myelin sheath and can be slowed by Lorenzo’s oil, but only before significant symptoms occur

Neurotransmitters

• Transmitting information across the neurons by living in the axon terminal bulbs

• They get recycled with the help of transporters, meaning they go back into the previous nerve

• When used, they jump to the next synaptic gap of the receptor site on the receiving neuron

• Examples

  • Acetylcholine

    • Memory

  • Dopamine

    • Pleasure

  • Epinephrine

    • Fight or flight

  • Gaba

    • Calm

  • Glutamate

    • Excitement

  • Serotonin

    • Mood

Psychiatric drugs

• Work with neurotransmitters to affect the reuptake, transmission, and absorption

• Example

  • SSRI blocks the recycling of serotonin, which increases the amount in the synapse and magnifies in effects

• Agonist

  • Activates receptor

• Antagonist

  • Blocks receptor