1. Neural and Hormonal Systems
Will Explain Why We FEEL……

2. It all Starts with the Neuron

3. Neuron Structure
Neurons do NOT touch each other- the space in between is call the synapse.

4. Types of Neurons
Sensory Neurons
Motor Neurons
Inter Neurons

5. Sensory Neurons (Afferent Neurons)
Take information from the senses to the brain.

6. Inter Neurons
Take messages from Sensory Neurons to other parts of the brain or to Motor Neurons.

7. Motor Neurons (Efferent Neurons)
Take information from brain to the rest of the body.

8. How a Neuron Fires It is an electrochemical process
Electrical inside the neuron
Chemical outside the neuron (in the synapse in the form of a neurotransmitter).
The firing is called Action Potential.

9. The All-or None Response
The idea that either the neuron fires or it does not- no part way firing.
Like a gun

10. Action Potential

11. How Neurons Communicate

12. Neurotransmitters
Chemical messengers released by terminal buttons through the synapse.
We should know at least 4 types and what they do.

13. Acetylcholine Its function is motor movement and maybe memory.
To much and you will….
Not enough and you will….
Lack of ACH has been linked to Alzheimer’s disease.

14. Dopamine Its function is motor movement and alertness.
Lack of dopamine is associated with Parkinson’s disease.
Overabundance is associated with schizophrenia.

15. Serotonin Function deals with mood control.
Lack of serotonin has been linked to depression.

16. Endorphins Function deals with pain control.
We become addicted to endorphin causing feelings.

17. Agonists and Antagonists

18. Divisions of the Nervous System

19. Human Nervous System Central Nervous System Brain + Spinal Cord
Peripheral Nervous System
Nerves (extensions from the CNS)
Provides Basis For Conscious Experience

20. Peripheral Nervous System
Afferent
Efferent
Skeletal - controls voluntary
movements of skeletal muscles
Autonomic - self-regulating, controls glands
& muscles of internal organs (e.g., heart)
Sympathetic
(arousing)
Parasympathetic
(calming)

21. Organization of the Nervous System
Central
Nervous System
Peripheral
Nervous System
Brain
Spinal Cord
Somatic
Autonomic

22. Skeletal/Somatic Nervous System
Nerves that connect to voluntary
skeletal muscles and to sensory receptors
Afferent Nerve Fibers
Axons that carry info away from the
periphery to the CNS
Efferent Nerve Fibers
Axons that carry info from
the CNS outward to the periphery

23. Autonomic Nervous System
Nerves that connect to the heart,
blood vessels, smooth muscles and glands
Sympathetic Division
Mobilizes the body’s resources
for emergencies (e.g., stim adrenal gland)
Fight or
Flight
Response
Cannon (1932)
Parasympathetic Division
Generally conserves bodily resources
(e.g., slows heart rate)

25. Central Nervous System (billions of neurons & trillions of connections)
Spinal Cord
Conduit between peripheral nervous system
and the brain
Organize certain behaviors without the brain
Conduit Function
- Ascending tract carries sensory info to brain
- Descending tract carries info from brain to muscles
Organization Function
- Governs reflexive actions of muscles

26. A Simple Reflex

27. A Simplified Neural Network
Neurons that learn to work together as a team.

28. The Endocrine System A system of glands that secrete hormones.
Similar to nervous system, except hormones work a lot slower than neurotransmitters.
Hormones
Neurotransmitters

29. The Major Endocrine Glands