The Nervous System Unit II: Biology and Behavior -What is it? -How does it affect our behavior?

The Nervous System Will Explain Why We FEEL… Pain Strong Nervous

The Nervous System is … A big communication system between the brain and the body. Helps us to  gain information that is going on inside and around our body  respond accordingly

The Nervous System is … Made up of nerves – bundles of long thin cells called neurons. Nerves send messages between the brain and the body.

The Nervous System is …  Neurons – fundamental unit of the nervous system nerve cell (5 parts) have the ability to communicate with one another

Neuron Structure

5 Major parts to a neuron 1.Dendrites 2.Cell Body 3.Axon- 1.can be thousandths of an inch or up to three feet! 4.Myelin Sheath- aids transmission 1.Degeneration can result in Multiple Sclerosis 5.Axon Terminals 1.Synaptic Gap- fluid filled and 5 millionth of an inch wide. Takes 10 millionth of a second to cross.

Synaptic Gap

The Nervous System is … Two Parts  1. Central Nervous System (CNS) brain and spinal cord – encased in bone

The Nervous System is…  2. Peripheral Nervous System (PNS) Nerves cells/ Neurons Connects the CNS to the body Carries information to and from the brain & spine. “Outer Edge”

2 Parts of the Peripheral Nervous System Somatic nervous system  Controls voluntary muscles and transmits sensory information to the CNS Autonomic nervous system  Controls involuntary body functions Heartbeat, Blood pressure, Breathing, Digestion…  Has two parts Sympathetic Parasympathetic

A “blueprint” of the Nervous System

How the Autonomic System affects our behaviors… Sympathetic Nervous System “Fight or Flight” Response Prepares our body to confront the situation or RUN! Remember that sympathetic, stress, and sympathy begin with “S”.

How the Autonomic System affects our behaviors… Parasympathetic Nervous System Restores the body’s energy reserves after an event has occurred. Remember that parasympathetic and peaceful both begin with “P”.

How it affects our behaviors…Sympathetic VS. Parasympathetic

How the Nervous Systems affects our behaviors …  Neurotransmitters – chemicals released by neurons which help them pass messages to the next neuron.  Three important neurotransmitters (over 100 are known) have a big influence on our feelings and behavior. Serotonin Dopamine Endorphins

Serotonin Function deals with mood control and sleep Abnormal levels of serotonin have been linked to depression and obsessive-compulsive disorder (OCD).

Dopamine Deals with motor movement and alertness. Deficiency of dopamine is associated with Parkinson’s disease. Excess is associated with schizophrenia. Antipsychotic drugs block dopamine receptors. Cocaine, nicotine, & amphetamines increase dopamine activity.

Endorphins Regulates pain control/pain perception during stress or trauma. Can give a euphoric feeling We can become addicted to endorphin causing feelings.  Similar to opiate addiction (morphine, heroin, & codeine).  Acupuncture

Another important neurotransmitter Acetylcholine-”uh-seet-ul-KO- leen”  Muscle control Low amounts linked to Alzheimer's Nerve gas & black widow venom cause too much acetylcholine to be released resulting in convulsions and suffocation. Nicotine mimics acetylcholine.