unit 2: the body and behavior the importance of the brain and biological influence!

Unit 2: The Body and Unit 2: The Body and BehaviorBehavior

The importance of the brain and biological influence!

The influence of the Body on The influence of the Body on BehaviorBehavior

The Phinneus P. Gage StoryThe Phinneus P. Gage Story- Back in the 1800’s, there was a man named Back in the 1800’s, there was a man named

Phinneus P. Gage who was working on a Phinneus P. Gage who was working on a railroad. His job was to use explosives to blow railroad. His job was to use explosives to blow away ground so that they could lay track. He away ground so that they could lay track. He was generally considered a kind and gentle man. was generally considered a kind and gentle man. One day an accident happened and the tamping One day an accident happened and the tamping rod was blown clean through his head. rod was blown clean through his head. Surprisingly he did not die, but he did show a Surprisingly he did not die, but he did show a complete personality change. He became a complete personality change. He became a drunk, was violent, and completely irresponsible. drunk, was violent, and completely irresponsible. This led to an interest in how the brain controls This led to an interest in how the brain controls behavior and personality.behavior and personality.

Physiological PsychologyPhysiological Psychology This field of study has This field of study has

been called been called physiological physiological psychology but is now psychology but is now more frequently called more frequently called Psychobiology, Psychobiology, biopsychology, or biopsychology, or neuroscience. The neuroscience. The focus of study is focus of study is generally how the brain generally how the brain controls all aspects of controls all aspects of our behavior.our behavior.

How the Nervous System How the Nervous System WorksWorks

The Nervous System is never at rest…It is The Nervous System is never at rest…It is always regulating your body functions.always regulating your body functions.

There are 2 primary parts to the structure of There are 2 primary parts to the structure of the Nervous System:the Nervous System:

1.) Central Nervous System (CNS): The Brain 1.) Central Nervous System (CNS): The Brain and Spinal Cord. and Spinal Cord. Note: The Note: The spinal cordspinal cord is is comprised of nerves that run up and down the comprised of nerves that run up and down the length of the back and transmit most length of the back and transmit most messages between the body and the brain.messages between the body and the brain.

2.) Peripheral Nervous System (PNS): 2.) Peripheral Nervous System (PNS): Nerves branching out from the spinal cord.Nerves branching out from the spinal cord.

Why is it important to protect the Spinal Why is it important to protect the Spinal Cord?Cord?

The Central and Peripheral The Central and Peripheral Nervous SystemNervous System


Messages to and from the brain travel Messages to and from the brain travel along the nerves, which are long, thin along the nerves, which are long, thin cells called cells called neuronsneurons..

Neurons:Neurons: The long, thin cells of The long, thin cells of nerve tissue along which messages nerve tissue along which messages travel to and from the brain.travel to and from the brain.

The Neurons consist of 3 basic parts:The Neurons consist of 3 basic parts:- - 1.) The Cell Body:1.) The Cell Body: is the main, or is the main, or center part of the neuron. It contains center part of the neuron. It contains the nucleus and produces the energy the nucleus and produces the energy needed to fuel neuron activity.needed to fuel neuron activity.


- 2.) The Axon:- 2.) The Axon: a tail like structure a tail like structure that carries information away from the that carries information away from the cell body.cell body.

- 3.) The Dendrites:- 3.) The Dendrites: are usually are usually small, short thin fibers that stick out small, short thin fibers that stick out from the cell body. They receive from the cell body. They receive impulses, or messages, from other impulses, or messages, from other neurons and send them to the cell body.neurons and send them to the cell body.

How do We Protect the How do We Protect the Neurons?Neurons?

Myelin Sheath: Myelin Sheath: Many axons, especially the longer Many axons, especially the longer ones are covered by a white fatty substance called ones are covered by a white fatty substance called myelin. myelin.

This “cover” not only helps to protect portions of the This “cover” not only helps to protect portions of the neuron, but it also helps to speed the transmission of neuron, but it also helps to speed the transmission of impulses.impulses.

In order for the nervous system to properly function, In order for the nervous system to properly function, there must be a space between each neuron. This there must be a space between each neuron. This space is called a space is called a synapse.synapse.

Synapse:Synapse: The gap that exists between individual The gap that exists between individual nerve cells.nerve cells.

What can happen if the Myelin Sheath is What can happen if the Myelin Sheath is destroyed? destroyed? Multiple Sclerosis (erratic and Multiple Sclerosis (erratic and uncontrolled behavior.)uncontrolled behavior.)

Diagram of a NeuronDiagram of a Neuron

How do the Neurons How do the Neurons Transmit Information?Transmit Information?

Action Action Potential:Potential: Neurons transmit Neurons transmit messages in the messages in the form of form of electrochemical electrochemical impulses called impulses called an action an action potential.potential.

Information is transmitted in the form of electrical impulses.

Continued…Continued…

These messages are transmitted by These messages are transmitted by the releasing of chemicals called the releasing of chemicals called “neurotransmitters.”“neurotransmitters.”

Neurotransmitters:Neurotransmitters: The chemicals The chemicals released by neurons, which released by neurons, which determine the rate at which other determine the rate at which other neurons fire. neurons fire.

And Now for a quick And Now for a quick break…break…

What just happened here?

An in depth look at the An in depth look at the Nervous SystemNervous System

Definition: The Nervous System Definition: The Nervous System connects our entire body and allows connects our entire body and allows communication that controls our communication that controls our behavior and bodily functions. behavior and bodily functions. There There are 2 major parts:are 2 major parts:

1.) The Central Nervous System (CNS)1.) The Central Nervous System (CNS) 2.) The Peripheral Nervous System (PNS)2.) The Peripheral Nervous System (PNS)

- We have already discussed much of the - We have already discussed much of the CNS, so lets break down the Peripheral CNS, so lets break down the Peripheral Nervous System…Nervous System…

Peripheral Nervous System Peripheral Nervous System (PNS)(PNS)

The Peripheral Nervous System is divided The Peripheral Nervous System is divided into 2 major parts:into 2 major parts:- 1.) The Somatic Nervous System - 1.) The Somatic Nervous System (SNS):(SNS): This is the part of the Peripheral This is the part of the Peripheral Nervous System that controls voluntary Nervous System that controls voluntary movement of the skeletal muscles…In other movement of the skeletal muscles…In other words, how you move.words, how you move.- 2.) The Autonomic Nervous System - 2.) The Autonomic Nervous System (ANS):(ANS): This is the part of the Peripheral This is the part of the Peripheral Nervous System that controls internal Nervous System that controls internal biological functions…In other words, your biological functions…In other words, your heartbeat, stomach activity, bowels, etc…heartbeat, stomach activity, bowels, etc…

Diagram of the Nervous Diagram of the Nervous SystemSystem

The Structure of the The Structure of the BrainBrain


The Human Brain is VERY Complex. It is still widely considered to be the most complex structure ever discovered or created by man.

There are approximately 10 billion nerve cells in the brain and each one has the potential to contact every other one.

There is however, NO relationship between brain size and intelligence.

What does relate to intelligence are the fissures, wrinkles, and folds of the brain. No animal has as many of these folds (convolutions) as a human except the porpoise.


Oxygen Consumption:Oxygen Consumption: The brain The brain needs oxygen to survive. The brain needs oxygen to survive. The brain contributes about 1/50contributes about 1/50thth of your body of your body weight yet consumes 25% of your weight yet consumes 25% of your oxygen.oxygen.

Deprivation of oxygen to the brain Deprivation of oxygen to the brain will lead to you passing out in 15 will lead to you passing out in 15 seconds and brain damage within 4 seconds and brain damage within 4 minutes.minutes.


Important:Important: There are NO pain There are NO pain receptors in the brain. If you have a receptors in the brain. If you have a headache it is usually due to dilation headache it is usually due to dilation of the blood vessels that surround of the blood vessels that surround the brain.the brain.

In other words, your brain cannot In other words, your brain cannot feel pain, but the blood vessels and feel pain, but the blood vessels and nerve system that surround it can.nerve system that surround it can.


The Brain Stem:The Brain Stem: Our basic body Our basic body processes are processes are mediated in the mediated in the brain stem, the brain stem, the portion of the portion of the brain just above brain just above the spinal cord.the spinal cord.

The “3” BrainsThe “3” Brains

The brain is comprised of three The brain is comprised of three major parts; the hindbrain, major parts; the hindbrain, midbrain, and forebrain.midbrain, and forebrain.

Hindbrain:Hindbrain: A part of the brain A part of the brain located at the rear base of the skull located at the rear base of the skull that is involved in the basic that is involved in the basic processes of life.processes of life.

The Hindbrain includes the The Hindbrain includes the Cerebellum, Medulla, and Pons.Cerebellum, Medulla, and Pons.

The “3” BrainsThe “3” Brains The CerebellumThe Cerebellum, which is located behind the , which is located behind the

spinal cord, helps control posture, balance and spinal cord, helps control posture, balance and voluntary movements.voluntary movements.

TheThe MedullaMedulla regulates vital body functions regulates vital body functions such as breathing , heartbeat, and a variety of such as breathing , heartbeat, and a variety of reflexes. This is why people that are called reflexes. This is why people that are called “brain dead” can still survive“brain dead” can still survive

Medulla? Where have I heard this word before? Oh Medulla? Where have I heard this word before? Oh Yeah!Yeah!

The PonsThe Pons, deals with the sensory and motor , deals with the sensory and motor information and regulates sleep and arousal. information and regulates sleep and arousal. It also functions as a bridge between the It also functions as a bridge between the Spinal Cord and the brain.Spinal Cord and the brain.


Midbrain:Midbrain: is a is a small part of the small part of the brain above the brain above the Pons. The midbrain Pons. The midbrain contains primitive contains primitive centers for vision centers for vision and hearing and and hearing and plays a role in the plays a role in the regulation of visual regulation of visual effects.effects.


Forebrain:Forebrain: A part of the brain that A part of the brain that covers the brains central core.covers the brains central core. Hypothalamus:Hypothalamus: Controls functions such Controls functions such

as hunger, thirst and sexual behavior.as hunger, thirst and sexual behavior. Cerebral Cortex:Cerebral Cortex: This is the center for This is the center for

higher mental process. It is what sets higher mental process. It is what sets humans apart from other animals. humans apart from other animals. The Cerebral Cortex gives you the The Cerebral Cortex gives you the

ability to learn and store complex and ability to learn and store complex and abstract information, and to project abstract information, and to project your thinking into the future.your thinking into the future.

Your Cerebral Cortex allows you to see, Your Cerebral Cortex allows you to see, read, and understand this sentence.read, and understand this sentence.

What Parts of the brain are What Parts of the brain are being used here?being used here?

The Lobes of the BrainThe Lobes of the Brain

The brain is divided into 2 The brain is divided into 2 hemispheres (right and left). The 2 hemispheres (right and left). The 2 hemispheres are divided by a band of hemispheres are divided by a band of fibers called the “corpus callosum.”fibers called the “corpus callosum.”

The brain also has 4 areas, or lobes. The brain also has 4 areas, or lobes. LobesLobes are the different regions that are the different regions that the brain is divided into.the brain is divided into.

1.) The Occipital Lobe:1.) The Occipital Lobe: This is where This is where the visual signals are processed. It is the visual signals are processed. It is located in the back of your brain.located in the back of your brain.

2.) The Parietal Lobe:2.) The Parietal Lobe: This is where This is where information from sensors all over the information from sensors all over the body is processed. (Supposedly located body is processed. (Supposedly located on the left side of the brain.)on the left side of the brain.)

3.) The Temporal Lobe:3.) The Temporal Lobe: This is where This is where your hearing, memory, emotion, and your hearing, memory, emotion, and speaking functions are processed. speaking functions are processed. (Supposedly located on the right side of (Supposedly located on the right side of the brain.)the brain.)

4.) The Frontal Lobe:4.) The Frontal Lobe: Is concerned with Is concerned with organization, planning, and creative organization, planning, and creative thinking. (I wonder where it is located.)thinking. (I wonder where it is located.)

Left and Right Left and Right HemispheresHemispheres

There are many myths about the There are many myths about the differences between the left and right differences between the left and right hemispheres of the brain. You may have hemispheres of the brain. You may have heard of people being “right or left heard of people being “right or left brained” before…This is simply not true.brained” before…This is simply not true.

In reality, the left and right side merely In reality, the left and right side merely compliment one another.compliment one another.

Right = Left….Left = Right…Right = Left….Left = Right…whaaaaaaaa?whaaaaaaaa?

The The Electroencephalograph…Electroencephalograph…

Wow that’s a long word…How about EEG Wow that’s a long word…How about EEG machine.machine.

What is it?What is it? It is a machine used to record the It is a machine used to record the

electrical activity of large portions of the electrical activity of large portions of the brain.brain.

Wires are connected to various areas of Wires are connected to various areas of your scalp, allowing the rhythms, or brain your scalp, allowing the rhythms, or brain waves caused by the neurons to be read.waves caused by the neurons to be read.

The Endocrine SystemThe Endocrine System Why do people run with Why do people run with

bulls in Spain? Why bulls in Spain? Why skydive? Heck, why do skydive? Heck, why do we ride roller coasters?we ride roller coasters?

Many do it for the Many do it for the “rush.”“rush.”

This “rush” comes from This “rush” comes from a hormone secreted by a hormone secreted by the endocrine system the endocrine system called called adrenalineadrenaline or or epinephrine.epinephrine.

It’s basically sending It’s basically sending your body into a state of your body into a state of emergency!emergency!

3 Cheers for Adrenaline!3 Cheers for Adrenaline!

The Endocrine SystemThe Endocrine System

Our body and Our body and behavior are behavior are controlled not only controlled not only through neural through neural impulses from the impulses from the brain but also brain but also through a slower through a slower chemical system chemical system called the called the endocrine system!endocrine system!

Isn’t that sweet Isn’t that sweet

The Endocrine SystemThe Endocrine System Endocrine System:Endocrine System: A chemical A chemical

communication system, using hormones, communication system, using hormones, by which messages are sent through the by which messages are sent through the bloodstream.bloodstream.

Hormones:Hormones: Chemical substances that carry Chemical substances that carry messages through the body in blood.messages through the body in blood.

Hormones can have various effects on your bodies Hormones can have various effects on your bodies behavior. They effect the growth of bodily behavior. They effect the growth of bodily structures such as muscles and bones, so they can structures such as muscles and bones, so they can effect what you can do physically. They also effect effect what you can do physically. They also effect how much energy you have to perform certain how much energy you have to perform certain actions, attractions you may have, and the actions, attractions you may have, and the different “moods” you may be in.different “moods” you may be in.

In fact, all of the physical differences between In fact, all of the physical differences between boys and girls are caused by hormones! boys and girls are caused by hormones! (testosterone)(testosterone) Jamie Lee Curtis example.Jamie Lee Curtis example.


The Importance of “glands.”The Importance of “glands.” The The Pituitary gland:Pituitary gland: is the center of is the center of

control of the endocrine system that control of the endocrine system that secretes a large number of hormones. secretes a large number of hormones.

This gland is located near the This gland is located near the “midbrain” and the “midbrain” and the HypothalamusHypothalamus, , which monitors the amount of which monitors the amount of hormones in the blood and sends hormones in the blood and sends messages to correct the imbalances.messages to correct the imbalances.


So what do these So what do these “hormones”“hormones” do? do? Well, to start off with…Hormones regulate:Well, to start off with…Hormones regulate:

- Emotional responses (awwww)- Emotional responses (awwww)

- Motivation (get off your lazy butt)- Motivation (get off your lazy butt)

- Physical Growth (Could you point - Physical Growth (Could you point me in the me in the direction of the gun show?)direction of the gun show?)

- Metabolism (ahhh, the fat burner!)- Metabolism (ahhh, the fat burner!)

- Oh yeah, almost forgot…Sexual - Oh yeah, almost forgot…Sexual arousal (Hey arousal (Hey there…)there…)

Have you bought your Have you bought your tickets to the gun show?tickets to the gun show?

Ron Burgandy says, “pay attention in psychology class…and learn how to get guns like these!”

The Endocrine SystemThe Endocrine System Other glands you should know!Other glands you should know! The Adrenal Gland: The Adrenal Gland: Only becomes active Only becomes active

when a person is angry of frightened! The when a person is angry of frightened! The release of adrenaline causes the heartbeat release of adrenaline causes the heartbeat and breathing to increase. This helps a and breathing to increase. This helps a person to generate extra energy!person to generate extra energy!

The Sex Glands:The Sex Glands: 1.) Testes:1.) Testes: Produce the Produce the male hormone “testosterone.” (low levels male hormone “testosterone.” (low levels are also found in women) are also found in women) 2.) Ovaries:2.) Ovaries: Produce the female hormones “estrogen” Produce the female hormones “estrogen” and “progesterone.” (low levels are also and “progesterone.” (low levels are also found in men)found in men)


Testosterone:Testosterone: is important in the physical is important in the physical development of males. Testosterone helps to development of males. Testosterone helps to decide the sex of a fetus. It is also important decide the sex of a fetus. It is also important for the growth of muscles and male sex for the growth of muscles and male sex characteristics.characteristics.

Estrogen and Progesterone:Estrogen and Progesterone: Are important in Are important in the growth of female sex characteristics. They the growth of female sex characteristics. They regulate the reproductive cycles of females. regulate the reproductive cycles of females. The levels of these hormones can vary, causing The levels of these hormones can vary, causing premenstrual syndrome (PMS) which could premenstrual syndrome (PMS) which could cause fatigue, irritability, and depression. (see cause fatigue, irritability, and depression. (see text pg. 172 if needed)text pg. 172 if needed)

Heredity and Heredity and EnvironmentEnvironment

How much do genetic How much do genetic factors contribute to factors contribute to our behavior?our behavior?

How much do How much do environmental factors environmental factors contribute to our contribute to our behavior?behavior?

Is it possible that a Is it possible that a combination of both combination of both genetic and social genetic and social factors have helped us factors have helped us to become what we to become what we are today?are today?


What is heredity?What is heredity? Heredity:Heredity: Is the genetic transmission of Is the genetic transmission of

characteristics from parents to their characteristics from parents to their offspring.offspring.

For example, do people become good athletes For example, do people become good athletes or are they born that way? Do people learn or are they born that way? Do people learn to do well in school, or are they simply born to do well in school, or are they simply born good at it?good at it?

Why do you think the concept of heredity has Why do you think the concept of heredity has caused so much controversy?caused so much controversy?

Change things.Change things.


The argument over The argument over the nature vs. the nature vs. nurture question nurture question has been going on has been going on for centuries!for centuries!

So what exactly are So what exactly are these “nature” and these “nature” and “nurture” terms “nurture” terms that we have been that we have been talking about?talking about?

Nature, mad at Nurture, haha I’m so

funny!


Nature:Nature: Refers to the characteristics Refers to the characteristics that a person inherits – in other words, that a person inherits – in other words, his or her biological “makeup.”his or her biological “makeup.”

Nurture:Nurture: Refers to environmental Refers to environmental factors, such as family, culture, factors, such as family, culture, education, and individual experiences.education, and individual experiences.

Sir Francis Galton vs. John Sir Francis Galton vs. John WatsonWatson

NatureNature NurtureNurture


Genes and Behavior!Genes and Behavior! GenesGenes are the basic units of heredity! They are the basic units of heredity! They

are reproduced and passed along from parent are reproduced and passed along from parent to child. to child.

All of the effects that genes have on behavior All of the effects that genes have on behavior occur through their role in building and occur through their role in building and modifying the physical structures of the body.modifying the physical structures of the body.

These structures must interact with their These structures must interact with their environment to produce behavior.environment to produce behavior.

Musicians example!Musicians example!


Twin StudiesTwin Studies One of the best ways to find out whether or One of the best ways to find out whether or

not a trait is inherited is to study twins.not a trait is inherited is to study twins. Identical Twins:Identical Twins: Twins who come from one Twins who come from one

fertilized egg; in other words, twins having fertilized egg; in other words, twins having the same heredity.the same heredity.

Fraternal Twins:Fraternal Twins: Twins who come from 2 Twins who come from 2 different eggs fertilized by 2 different sperm.different eggs fertilized by 2 different sperm.

How can studying twins help us to How can studying twins help us to understand Nature vs. Nurture?understand Nature vs. Nurture?

Can Studying Twins help to Can Studying Twins help to Explain Nature vs. Nurture?Explain Nature vs. Nurture?

Is this behavior a result of heredity or of societal pressures?


Twins that grow up in the same Twins that grow up in the same house share the same general house share the same general environment, but identical twins environment, but identical twins share the same genes.share the same genes.

Sooooo…if identical twins who grow Sooooo…if identical twins who grow up together prove to be more alike up together prove to be more alike on a specific trait than fraternal on a specific trait than fraternal twins do, it probably means that twins do, it probably means that genes are important for that trait!genes are important for that trait!

Nature vs. Nurture - Nature vs. Nurture - TwinsTwins

unit 2: the body and behavior the importance of the brain and biological influence!

Documents

nervous system worksmessages

cell body

peripheral nervous system

central nervous system

brain travel

body functions

peripheral nervous systemhow

brain controls behavior