35 Neuron firing like a Toilet Like a Neuron, a toilet has an action potential. When you flush, an “impulse” is sent down the sewer pipe
36 Neuron firing like a Toilet 2. Like a neuron, a toilet has a refractory period. There is a short delay after flushing when the toilet cannot be flushed again because the tank is being refilled
37 Neuron firing like a Toilet Like a Neuron, a toilet has a resting potential. The toilet is “charged” when there is water in the tank and it is capable of being flushed againLike a Neuron, a toilet operates on the all-or-none principle – it always flushes with the same intensity, no matter how much force you apply to the handle
38 All-or-None Principle The principle that if a neuron fires it will always fire at the same intensityAll action potentials are of the same strength.A neuron does NOT fire at 30%, 45% or 90% but at 100% each time it fires.
39 Communication Between Neurons Module 7: Neural and Hormonal Systems
40 SynapseThe space between the terminal buttons on one neuron and dendrites of the next neuron
52 Acetylcholine (ACh)Enables muscle action, REM sleep, and memoryUndersupply, as ACh-producing neurons deteriorate, marks Alzheimer’s disease
53 Dopamine Reward and Motivation, Motor Control over Voluntary Movements Excessive dopamine receptor activity is linked to schizophrenia; a lack of dopamine produces the tremors and lack of mobility of Parkinson’s disease
54 Serotonin Affects mood, hunger, sleep, and arousal Undersupply is linked to depression; Prozac and other anti-depressants raise serotonin levels
55 Helps to control alertness and arousal NorepinephrineHelps to control alertness and arousalUndersupply can depress mood
56 GABAMuscular movement; inhibition of brain activityUndersupply linked to seizures, tremors, and insomniaAnxiety disorders
57 Glutamate Involved in memory Oversupply can overstimulate the brain, producing migraines or seizures
58 EndorphinsNatural opiates that are released in response to pain and vigorous exercise
59 Adrenaline Burst of Energy (small amounts in brain) EpinephrineAdrenaline Burst of Energy (small amounts in brain)
60 Drugs and Chemical Interactions with Neural Transmission
62 Neural Communication: The Neural Chain Module 7: Neural and Hormonal Systems
63 Receptor CellsSpecialized cells in the sensory systems of the body that can turn other kinds of energy into action potentials that the nervous system can processReceptor cells in the eye turn light into a neural impulse the brain understands.
64 Sensory NervesNerves that carry information to the central nervous systemConnect the sense organs to the brain and spinal cord
65 InterneuronsNerve cells in the brain and spinal cord responsible for processing information related to sensory input and motor output
66 Motor NervesNerves that carry information from the central nervous systemCarries messages from the brain and spinal cord to other parts of your body
72 Most information travels from the body, up the spinal cord, is processed by the brain, sent back down the spinal cord, and then back to the body with behavior instructions. The exception to this general pathway is reflexes.
73 Reflexes are controlled by the spinal cord without any conscious effort on behalf of the brain. Reflexes serve as primitive responses that protect our bodies from danger and help us adjust to our surroundings.
74 ReflexWe cough, for example, when an irritant enters our windpipe and we need to expel it through our mouth. We sneeze when we need to clear our nasal air passages of irritants and allergens. We blink when danger threatens the sensitive tissues of the eye and when we need to moisten and clean the cornea. (This reflex occurs 900 times an hour!) We yawn when nerves in the brain stem find there's too much carbon dioxide in the blood.