Download neuron and nervous system

Neuron and Nervous System
Biological Psychology: concerned with the links between biology
and behavior (also called neuropsychology)
Neuron: a nerve cell; the basic building block of
the nervous system
Action Potential: a neural impulse; a brief
electrical charge that travels down an axon
**Neurons that are stimulated cause a brief
electrical charge; if strong enough, the nerve fires
**ALL OR NOTHING
Threshold: level of stimulation required to trigger a neural impulse;
excitatory signals minus inhibitory signals must equal a minimum intensity
Neural Communication
Neurotransmitters: chemical messengers that
traverse the synaptic gaps between neurons
Agonist – mimic neurotransmitters
Example: Morphine mimics endorphins
Antagonist – block neurotransmitters
Example: Poison blocks muscle movement
Acetylcholine (Ach) – Enables muscle action, learning, and memory
**Brains of those suffering from Alzheimer’s have deteriorating Achproducing neurons
Endorphins – natural neurotransmitters linked to pain control and pleasure
**”Runner’s High” is an example of endorphin release
The Nervous System
Nervous System – body’s speedy, electrochemical communication network
consisting of nerve cells
Central Nervous System (CNS) – brain and spinal cord
**Neural networks – interconnected neural cells; more connections made as
experience gained
Peripheral Nervous System (PNS) – sensory and motor neurons that
connect the CNS to the rest of the body
Sensory Neurons –
sends incoming information from sense receptors to CNS
Interneurons
– CNS internal communication neurons; intervene b/w sensory & motor
Motor Neurons – sends outgoing information from CNS to muscles
and glands
CNS CNS CNS
FEW MILLION BILLIONS FEW MILLION
Reflex – automatic response to sensory stimulus; motor neuron reacts to
sensory neuron w/o going to brain