Nervous system chap 3

• The brain is the control centre of the nervous system, responsible for processing information from sensory receptors.
• Neuron's carry the information around the body.
• The functions of the brain include controlling vital functions, receiving information from the outside world via sense, higher order functions and emotions
• Detection, message spinal cord, spinal cord decides, messages brain, response
• CNS receives sensory information from PNS and sends motor information to PNS
• Sensory, Afferent (toward), Motor, Efferent (away) (the brain)
• Peripheral nervous system(PNS): sends sensory information to brain and receives motor information made up of Muscles, Organs, Glands
• Somatic (M) nervous system: voluntary movements of muscles ordered from receptor sites to CNS
• Autonomic (OG) nervous system: involuntary movement from the organs and glands
• FFF: fight - stay and attack, flight - run, freeze - unnoticed and undetected
• FFF: occur due to the sympathetic nervous system and increase the heart rate
• Freeze is triggered when both Sympathetic and Parasympathetic nervous systems occur at the same time
• Parasympathetic: relating to the part of the autonomic nervous system which balances the action of the sympathetic nerves. It consists of nerves arising from the brain and the lower end of the spinal cord and supplying the internal organs, blood vessels, and glands.
• Parasympathetic nervous system: like a parachute and calmes the body down following stress or heightened arousal returning back to a state of homeostasis and regulatory
• Sympathetic nervous system: prepares the body for action cause of a potential threat, certain functions are heightened or increased while others are momentarily disregarded
• Sympathetic nervous system: increased heart rate, liver, kidney, pupils while digestion and bladder are slowed
• The spinal cord transmits messages between the brain and body parts below the neck.
• Spinal Cord: long bundle of nerve fibers that extends from the medulla oblongata (brain) to the lumbar region of the vertebral column; it serves as an important pathway for sensory information traveling up to the brain and motor impulses going out to various parts of the body.
• Sympathetic:

  increased heart rate

  relaxed bladder

  increased glucose

  dilated pupils

  inhibits digestion

  inhibits liver, kidney and saliva
• Parasympathetic:

  decreased heart rate

  stimulates bile production (glucose)

  constricted pupils

  contracted bladder

  enables digestion and saliva
• SRP: sprouting, rerouting and pruning
• Neuroplasticity: ability of the brain to physically change in response to experience
• adaptive plasticity occurs due to brain trauma or damage
• Developemental plasticity occurs naturally over a lifespan and has critical periods
• Synaptic plasticity ability of synaptic connections to change over time in response to activity or experience
• Hebbs cells that fire together wire together, that is, the more often a nerve is stimulated, the more likely it is to fire again
• Long term potential (LTP): the long lasting and experience dependent strengthening of synaptic connections that are regularly activated
• Long term depression (LTD): the long lasting and experience dependent weakening of synaptic connection between neurons that are not regularly activated
• LTP INCREASES STRENGTH OF CONNECTION BETWEEN NEURONS
• LTD WEAKENS EFFICIENCY OF SYNAPTIC CONNECTIONS
• Proliferation (pro life growing)

  Migration (moving or relocating)

  Circut Formation (form of the pre and post synaptic neurons and the synaptic gap)

  either

  Circut pruning (ridding or decreasing)

  Myelination (myelins forms around axon strengthening neuron)
• Structure of a neuron

  
• dendrite: receives incoming neural messages from other neurons and sends outgoing messages to other neurons
• Soma: the body of the neuron, containing the nucleus with the genetic material for the neuron
• Axon: the pathway down which the neuron messages travels
• Myelin sheath: fatty tissue that encases the axon to aid in speed of transmission
• Axon terminals: exit pathways for neural messages to make their way to the next neuron
• terminal buttons: releases a chemical substance known as a neurotransmitter to a receiving neuron for communication purposes; also referred to as synaptic knobs
• Dave (dendrite) Still (soma) AdMireS (axon) (myelin) (sheath) ATrocious (axon) (terminals) Teddy (terminal) Bears (buttons)
• Neurotransmitter: the chemical substance released by the terminal button of a neuron, necessary for neural communication