The Nervous System Presents: Pain In association with Tanya and Stefan

Introduction  The nervous system is the system of cells, tissues, and organs that regulates the body's responses to internal and external stimuli.  It is composed of the brain, spinal cord and nerves.  Nerves are bundles of happiness neurons.

The Neuron Family A neuron is a nerve cell. It is electrically excitable, and thus processes and transmits information by electrical and chemical signals. There are three types of neurons in the human body.

Parts of a Neuron

How Do They Work?  Information is conveyed through the nervous system as nerve impulses.  These impulses travel from neuron to neuron via a junction called a synapse  Release chemicals called neurotransmitters  Neurotransmitter molecules cross the synapse and stimulate the next neuron to fire an impulse of its own

Action Potential  The nerve impulses are also known as action potentials  The impulse is based on movement of positively charged Na+ and K+ ions through the cell membrane  Three states of the axon as the nerve impulse passes through it:  Resting Potential  Depolarization  Repolarization

The Big Picture Stimulus causes action potential at pain receptors AP travels to dorsal horn in the spinal cord through afferent neurons Afferent Neurons Dorsal Horn Efferent Neurons Directs nerve impulses to the brain as well as the affected area via efferent neurons

Our Adventure Into The World of Neurons via Magic School Bus

Visual Components  Neurons  Sensory Neurons  Motor Neurons  Interneurons  Neuron Parts:  Cell Body (Soma)  Axon  Schwann Cells  Myelin Sheath  Axon Terminal  Dendrites  Skin cells  Synapse  Neurotransmitters  Synaptic Vesicles  Ion Channels  Receptors  Pumps  Spinal Cord  Bundle of Axons  Epidural Space  Stimulus

The Polysynaptic Reflex to Pain

Canada’s Next TOP Model  Will be modeled using agent based modeling  Animations used for ion channel transfer  Impulse will be propagated through ion movement  Level of detail:  No mitochondria and neurotubules,  when NT are in synaptic vesicles, they will not be individually packed into the vesicle but represented as a single entity, then in the synaptic space divided into multiple objects

Computational Components  Time will be slowed down as impulses move too fast to be perceived  Axon will light up in the area the impulse travels through  Sensory Adaptation  Shows a decrease in sensitivity during continued stimulation  Adjustable parameters for the stimulus  Amount and Time stimulus is applied  Adjustable parameters for the addition of painkillers into the model  Possible graphs to support the model  Action Potential  Interactions with brain will be kept to a minimum

Sources  Freudenrich, C. (2010). How Your Brain Works. Retrieved August 5, 2010, from How Stuff Works: body/systems/nervous-system/brain2.htm  Jacques, E. (2009, July 21). How We Feel Pain. Retrieved August 5, 2010, from About.com:  Kapit, W., Macey, R. I., & Meisami, E. (2000). The Physiology Coloring Book. San Francisco, CA, US: Addison Wesley Longman, Inc.  Parker, S. (2009). The Concise Human Body Book. Toronto, ON, Canada: Dorling Kindersley.  Unknown. (n.d.). Nervous System. Retrieved August 5, 2010, from Web- Books: books.com/eLibrary/Medicine/Physiology/Nervous/Nervous.htm