Download Ch 2 neurotrans and nervous sys

TYPES OF
NEUROTRANSMITTERS
Acetylcholine (ACH)
• Deals with motor
movement and
memory.
• Too much and you
will….
• Too little and you
will…
• Lack of ACH has
been linked to
Alzheimer’s disease.
Serotonin
• Involved in mood
control.
• Lack of serotonin
has been linked to
clinical depression.
Dopamine
• Deals with motor
movement and
alertness.
• Lack of dopamine
has been linked to
Parkinson’s disease.
• Too much has been
linked to
schizophrenia.
Endorphins
• Involved in pain
control.
• Many of our most
addictive drugs deal
with endorphins.
Select Neurotransmitters
Acetylcholine (Ach)
– Involved in muscle movement and memory (undersupply - ALZ)
Serotonin
– Involved in mood and sleep (Undersupply - Depression)
Dopamine
– Involved in movement and reward systems (Excess - Schizophrenia,
undersupply - Parkinson‘s )
GABA (gamma-aminobutyric acid)
– Inhibitory NT (undersupply – seizures, tremors, insomnia)
Norepinephrine
– Involved in arousal, mood, and sympathetic nervous system activation
(Bipolar)
Endorphins
– elevate pleasure/mood and reduce pain, act by either increasing or
decreasing specific NT activity, mimic effects of opium based drugs
like morphine
Neural Communication
Serotonin Pathways
Dopamine Pathways
Drugs can be…..
• Agonists- make neuron fire
• Antagonists- stop neural firing
• Reuptake Inhibitors- block
reuptake
Some Drugs work on receptors
• Some drugs are shaped like
neurotransmitters
• Antagonists : fit the receptor but poorly and
block the NT
– e.g. beta blockers (Beta blockers block the action of epinephrine
(adrenaline) and norepinephrine (noradrenaline) part of the
sympathetic nervous system which mediates the "fight or flight"
response.)
• Agonists : fit receptor well and act like the
NT
– e.g. nicotine
Neural Communication
Neurotransmitter
molecule
Receptor site on
receiving neuron
Receiving cell
membrane
Agonist mimics
neurotransmitter
Antagonist
blocks
neurotransmitter
Neural
Communication:
The Neural Chain
Neurons and Synapses
Types of Neurons
Sensory
Motor
Interneurons
Motor Neurons
• Nerves that carry outgoing information from
the central nervous system
• Carries messages from the brain and spinal
cord to other parts of your body
Sensory
Neuron
Brain
Spinal
Cord
Motor
Neuron
Sensory Neurons
• Nerves that carry incoming
information to the central nervous
system
Sensory
• Connect the
Neuron
sense organs
to the brain
and spinal cord
Brain
Spinal
Cord
Interneurons
• Connect the other 2 neurons. Only
found in the brain and spinal cord.
Sensory
Neuron
Brain
Spinal
Cord
Motor
Neuron
A Neural Chain
The Structure of the
Nervous System
A Simplified Neural Network
Neurons that learn to work together as a team.
The Nervous System
Nervous System
the body’s speedy, electrochemical communication
system
consists of all the nerve cells of the peripheral and
central nervous systems
Nerves
neural “cables” containing many axons
part of the peripheral nervous system
connect the central nervous system with muscles,
glands, and sense organs
The Nervous System
Central Nervous System (CNS)
the brain and spinal cord
Peripheral Nervous System (PNS)
All nerves that are not encased in bone
Everything but the brain and spinal cord
the sensory and motor neurons that connect the
central nervous system (CNS) to muscles and
organs (Peripheral = outer region)
Divided into two parts
Somatic
Autonomic
The Nervous System
Subparts of the nervous system
Somatic Nervous System
• Controls voluntary muscle movement
• Uses motor neurons
Autonomic Nervous System
• Controls the glands and muscles of the
internal organs
• Monitors the autonomic functions
• Controls breathing, blood pressure, and
digestive processes
• Divided into the sympathetic and
parasympathetic nervous systems
Sympathetic Nervous System
• The part of the autonomic nervous system
that arouses the body to deal with perceived
threats
– Automatically accelerates heart rate, breathing,
dilates pupils, slows down digestion
• Fight or flight response
Parasympathetic Nervous System
• Automatically slows the body down
after a stressful event
– Calms the body – Heart rate and breathing
slow down, pupils constrict and digestion
speeds up
Reflexes
• Normally, sensory
(afferent) neurons
take info up through
spine to the brain.
• Some reactions
occur when sensory
neurons reach just
the spinal cord.
• Survival adaptation.
The Sympathetic and Parasympathetic Divisions of the
Autonomic Nervous System
The Endocrine
System
Endocrine System
A second type of communication
system in the body made up of a
network of glands that produce
hormones-- chemical
messengers that circulate in the
blood
• Examples of hormones:
–
–
–
–
Estrogen/testosterone
Thyroid
growth hormone
follicle-stimulating hormone
Hormone
• Chemical messengers produced by the endocrine glands and
circulated in the blood
• Similar to neurotransmitters in that they are also messengers
• Slower communication system, but with longer lasting
effects
Hormones
Neurotransmitters
Endocrine System/ Endocrine Glands