Brain, Body, & Behavior NERVOUS SYTEM NEURONS BRAIN NEUROTRANSMITTERS ENDOCRINE SYSTEM IMMUNE SYSTEM
Some cells in your nervous system are more than 3 feet long? • Our bodies produce natural painkillers similar to some narcotic drugs? • 95% of fetuses suck their right thumbs? • Raising the body temp. of a finger may relieve the pain of a migraine headache? • Men’s & women’s bodies produce both male & female sex hormones? DID YOU KNOW THAT…
ALL behaviors & mental processes are influenced by or based on biology • study the brain in detail • Behaviors & mental processes can’t be fully understood through bio alone!!! • Oversimplify = not credible Intro
AVOID THE “BIOLOGY IS DESTINY” PITFALL • WE ARE THE PRODUCT OF AN INTRICATE INTERACTION OF BIO. & ENVIRONMENTAL FACTORS
Brain, spinal cord, nerves • processes info. from: • 1) inside the body • 2) external environ. • NEURONS • cells in the nervous system (brain cells & nerve cells • Specialized to respond to signals & send signals of their own NERVOUS SYSTEM
INPUT: receiving info. about what is going on inside & outside (senses) your body • PROCESSING: combining info. with past experiences (if any) & decide how to react/behave • OUTPUT: brain activates muscles to act on what to do about it (the info. received) 3 Main Functions
Q: How can the nervous system do this? • A: Neurons! must COMMUNICATE • Neurotransmitters • Electrical signals • 100 billion neurons that are separate but still able to alternate signals from one circuit to another INPUT PROCESSING OUTPUT
1) CENTRAL NERVOUS SYSTEM • brain & spinal cord • Info is sent here from PNS to be shot up the spinal cord to the brain to be processed . • The ‘CEO’ of the nervous system DIVISIONS
2) PERIPHERAL NERVOUS SYTEM • all nerves not in the brain & spinal cord. • PNScollects info. to be sent to the CNS.
2 subdivisions of PNS • Somatic: • sensory nerves & motor nerves • Autonomic: • Automatic processes • Signals must make a ‘full circuit’ in order for you to process sensory & motor info • Peripheral nerves spinal cord brain spinal cord original peripheral nerves
Nerve cell • more advanced than your typical cell • involved w/ receiving, moving, & processing info. • PARTS • Cell Body Receptor Axon terminals • Dendrites Axon • Synapse Vesicles • Neurotransmitters Myelin NEURONS
Cell Body: contains a nucleus that caries DNA info; determines how the cell functions • Dendrites: fibers of the neuron that receive signals/info from the axons of other neurons. Dendrites Detect signals from other neurons • Carries the signals to the cell body to be interpreted PARTS OF THE NEURON
Axon: fibers that carry signals away from the cell body to where communication occurs with other neurons. Axons carry signals Away from the cell body to axon terminals • Axon Terminal: areas @ the end of an axon where neurotransmitters are released • Synapse: gap between neurons. Where neurotransmitters “jump” from one neuron to another.
Neurotransmitters: chemicals that transfer information from one neuron to another by “jumping” across the synapse. • can only “fit” into its own receptors • Vesicles: Little “bubbles” where neurotransmitters are stored at the end of an axon. • Receptor: where neurotransmitters fit into the receiving dendrite of the next neuron. • Myelin sheath: insulating protein layer that surrounds the axon in order to speed up communication & contain the electric pulses.
Dendrites accept neurotransmitters from other neurons and transfer that info to the cell body. • That info is shot down the axon in the form of electrical signals. • When these electrical signals reach the end of the axon, it releases the neurotransmitters (chemical signals) from the vesicles. HOW DO NEURONS COMMUNICATE?
The neurotransmitters “jump” across the gap between neurons, known as the synapse. • The neurotransmitters then bind to their proper receptors on the dendrites of the receiving neuron (like a puzzle). • Dendrites get excited when they detect neurotransmitters in their receptors & send info. to the cell body. • THE WHOLE PROCESS STARTS OVER
1) NEURONS EITHER FIRE OR DON’T FIRE. IT’S “ALL OR NOTHING” • rate of firing can differ • 2) Can only communicate w/ other neurons that are close to them. • 3) MUST MAKE FULL CIRCUIT! • Nerves spinal cord brain spinal cord same nerves Rules of Neural Communication
When you are ‘killing brain cells’, you are killing NEURONS & CONNECTIONS!
Wasting away of motor neurons in brain & spinal cord • Progressive, disabling, & fatal • Symptoms • inability to control mvmt, loss of muscle control • Neurons waste away = muscles waste away too LOU GEHRIG’S DISEASE
Brain dev. disorder – abnormalities & deficits in: • Social interaction • Restricted interests & repetitive behavior • Deficit in mirror neurons (?) • Probs empathizing w/ & imitate others AUTISM
Immune system slowly destroys Myelin sheaths • Slows communication • Progressive & fatal • 350,000 Americans • onset = 20 – 40 yrs old • Symptoms: loss of the ability to speak, walk, write, eventually breath & heartbeat MULTIPLE SCLEROSIS (MS)
Sits in a fluid • There are psych. changes when the brain experiences trauma or chemical changes . • DIVIDED INTO 3 MAIN PARTS • a.k.a ‘the 3 brains’ • each contains specialized structures THAT MAGNIFICENT BRAIN OF YOURS!
most primitive part; vitals • Incoming signals reach here 1st • Medulla: vital bodily functions (breathing, swallowing, circulation) • Reticular Formation: “net”work of fibers (neurons); arousal & attn • Cerebellum: basic motor activities; coordination (sequencing/ timing); posture, balance, normal speech patterns HINDBRAIN
Integrates mvmt w. sensory info, & relays it up to the rest of the brain • Ex. Loud noise turn in head in direction of the sound MIDBRAIN
most complex aspects • Thalamus: relay station for sending messages to & from parts of the brain • Hypothalamus: ‘pleasure center’; regulates hunger, thirst & sex drive; controls rage • Hippocampus: regulateemotion & form LT memories FOREBRAIN
Cerebrum: high level thinking process • Emotions, memories, personality, logic, decision making, planning, etc. • Largest part • Div. into 2 hemispheres (halves) & 8 lobes
Corpus Callosum –band of fibers in the mid of the brain – connects the 2 hem.
Cerebrum / 4 lobes • Each is specialized • all work together in order to collect, analyze, store, & respond to information • All 4 lobes are found in both hemispheres (mirror image) • Deep groves in the brain mark where the difft lobes are LOBES of CEREBRUM
PARIETAL • body & skin sensations • Touch, pressure, temp., pain, movement • TEMPORAL • sound sensations • auditory info; involved in hearing, memory, speaking
OCCIPITAL • visual info (vision center) • Optic nerves directly connected to here • FRONTAL • Arranges incoming info into meaningful perceptions • Most advanced cog. processes • Language, organizing, planning, problem solving, decision making, personality, learning, dreaming, emotions, memories, creativity, & thinking • Control of the body
major changes in behavior • Able to see the connection btw damaged parts of the brain & behavior • Why did he survive? POOR PHINEAS!
Before • friendly; good judgment, cooperative, enjoyable • After • short-temper; swore; urinated & undressed in public; said inappropriate things; aggressive; violent; • Damage to what lobe? FRONTAL! • Severe changes in personality, judgment, & rational thought • prevented censoring of thoughts, ideas, & social functioning
Lateralized • 2 hemispheres are specialized for processing certain kinds of info. • Each hem. controls the opposite ½ of the body • Right 1/2 controls left side of body • Left 1/2 controls right side of body LATERALIZATION OF THE CEREBRUM
We constantly use both • compliment each other • Work in harmony to jointly control human functions • 2 hems. connected by the corpus callosum. (communication) • processed in one half, then sent to the other to be processed… then both ‘analysis’ are integrated to produce one flow of thought & behavior
FUNCTIONS/ CHARACTERISTICS • LEFT HEMISPHERE • LANGUAGE (verbal): speaking, understanding language, reading, writing • Sequences & order; time • Math: algebra, calculus, physics • Detail-oriented • ‘Safe & logical’ • Process info. logical & sequential
Right Hemisphere • Nonverbal: body language; emotions; visual symbols & images • Spatial: patterns; objects in ‘space’; art & music • Math: geometry • ‘Big picture’ oriented • ‘Impulsive’ • Process info. intuitively, simultaneously, & randomly