What is the control point of the central nervous system?
the brain (the brains principle task is to process and relay information)
What are the three major areas of the brain?
the cerebrum, cerbelllum, and brain stem
How does the brain differ from most other organs in the body?
While most organs function to maintain homeostasis, the brain is constantly changed by its interactions with the environment.
spinal cord
the main communication link between the brain and the rest of the body (central<----->peripheral); 31 pairs of spinal nerves branch out from the spinal cord, connecting the brain to different parts of the body
reflex
a quick, automatic response to a stimulus; processed directly in the spinal cord
cerebrum
largest region of the human brain; responsible for the voluntary, or conscious, activities of the body; site of intelligence, learning, and judgement
corpus callosum
band of tissue that connects the left and right hemispheres of the cerebrum
cerebral cortex
outer layer of the cerebrum; consists of densely packed nerve cell bodies known as gray matter; processes information from the sense organs and controls body movements, thoughts, plans, and learning abilities are processed here; folds and grooves on the o
gray matter
densely packed nerve cell bodies in the cerebral cortex
white matter
inner layer of the cerebrum; whitish color comes from bundles of axons with myelin sheaths; axons connect different areas of the cerebral cortex or the cerebrum to other areas of the brain
limbic system
emotion, behavior, memory; feelings of satisfaction and well-being
thalaumus
recieves messages from sensory receptors troughout the body and then relays the information to the proper region of the cerebrum for further processing
hypothalamus
control center for recognition and analysis of hunger, thirst, fatigue, anger, and body temperature; also helps to coordinate the nervous and endocrine systems
cerebellum
second largest region of the brain; where information about muscle and joint position (and other sensory inputs) are sent; doesnt command muscles to move but coordinates and balances the actions of these muscles (graceful and efficient movements)
brain stem
connects the brain and spinal cord
What are the three regions of the brain stem?
midbrain, pons, medulla ablongata; each of these regions regulate the flow of information between the brain and the rest of the body; does work of keeping the body functioning even when you have lost consciousness (breathing, heart rate, swallowing, blood
frontal lobe
evaluates consequences, makes judgments, and forms plans
temporal lobe
hearing and smell
parietal lobe
reading and speech
occipital lobe
vision
What does the synapse do?
makes the brain work by transferring messages from cell to cell-->does the conscious work of thinking and the less conscious work of producing feelings and emotions
How do drugs affect brain?
The particular group of synapses that the drug effects use the neurotransmitter dopamine and are associated with the brain's pleasure and reward centers
dopamine
released by hypothalamus and the limbic system; dopamine molecules stimulate other neurons across these synapses which produces the sensation of pleasure and a feeling of well-being
methamphetamine
releases flood of dopamine-->instant high
cocaine
keeps dopamine in the synaptic region longer-->intensifies pleasure and suppresses pain
opium poppies (heroin, etc.)
stimulate receptors elsewhere in the brain that lead to dopamine release
nicotine
increases release of dopamine
How does the brain react to excessive dopamine levels?
reduces the number of receptors for the neurotransmitter-->normal activites no longer produce the sensations of pleasure they once did-->addiction; feel depressed and sick without these drugs (need higher amounts of drugs, alcohol, etc. with fewer recepto