Module 4 handouts

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Module 4

NEUROSCIENCE AND NEUROSCIENCE AND BEHAVIOR / BEHAVIOR /

BIOLOGICAL BASES OF BIOLOGICAL BASES OF BEHAVIORBEHAVIOR

*Biological Psychology*Biological Psychology-- concerned with the links concerned with the links between biology and behaviorbetween biology and behavior

Warm UpWarm UpGet into 4 groups. Make a Y. Everyone except the Get into 4 groups. Make a Y. Everyone except the front and back persons are blind.front and back persons are blind.–– Create a system of communication that does not involve Create a system of communication that does not involve

verbal or visual communication among “survivors.” verbal or visual communication among “survivors.” Touching is allowed.Touching is allowed.

Create a system of communication that does not Create a system of communication that does not i l dit i l i ti b t i l dit i l i ti b t involve auditory or visual communication between involve auditory or visual communication between “islands.” Seeing people are mute and cannot “islands.” Seeing people are mute and cannot touch other seeing people. You cannot cross the touch other seeing people. You cannot cross the gap. gap. –– One catch: only one person from each island can send One catch: only one person from each island can send

messages among islands and one person from each island messages among islands and one person from each island can receive the message. can receive the message.

The goal: Send the final message to the rest of the The goal: Send the final message to the rest of the group.group.

AgendaAgenda

Module 4: Neural and Hormonal Module 4: Neural and Hormonal SystemsSystems––NeuronsNeurons

Action potentialsAction potentials––Action potentialsAction potentials––Synaptic communicationSynaptic communicationExit ticketExit ticket

Fact or FalsehoodFact or Falsehood

1.1. A small amount of brain tissue from A small amount of brain tissue from a person cannot be distinguished a person cannot be distinguished from that of a monkey.from that of a monkey.

22 The human brain produces its own The human brain produces its own 2.2. The human brain produces its own The human brain produces its own natural opiates that elevate mood natural opiates that elevate mood and ease pain.and ease pain.

3.3. The brain accounts for a larger The brain accounts for a larger percentage of body weight in percentage of body weight in humans than in any other species.humans than in any other species.


1.1. Electrically stimulating a cat’s brain Electrically stimulating a cat’s brain at a certain point can cause the at a certain point can cause the animal to cower in terror in the animal to cower in terror in the presence of a small mousepresence of a small mousepresence of a small mouse.presence of a small mouse.

2.2. Both animals and humans seem to Both animals and humans seem to have reward centers located in the have reward centers located in the brain.brain.

3.3. We ordinarily use only 10 percent of We ordinarily use only 10 percent of our brains.our brains.

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1.1. Some people can write but are Some people can write but are unable to read.unable to read.

2.2. If a blind person uses one finger to If a blind person uses one finger to read Braille the brain area read Braille the brain area read Braille, the brain area read Braille, the brain area dedicated to that finger expands.dedicated to that finger expands.

3.3. Adult humans cannot generate new Adult humans cannot generate new brain cells.brain cells.

4.4. Some people have had the Some people have had the hemispheres of their brains split hemispheres of their brains split with no apparent ill effect.with no apparent ill effect.

Phrenology Phrenology

Franz GallFranz GallGermanyGermanyEarly Early 1800’s1800’s1800 s1800 sbumps = bumps = mental mental abilitiesabilities37 traits37 traits

HOW DOES THIS…HOW DOES THIS… LEAD TO THIS?LEAD TO THIS?

We are…We are…

Systems: A group of interacting, Systems: A group of interacting, interrelated, or interdependent interrelated, or interdependent elements forming a complex whole.elements forming a complex whole.

Biological, Psychological, SocialBiological, Psychological, Social

What is the smallest level of What is the smallest level of analysis?analysis?

We are…We are…

What is the smallest level of What is the smallest level of analysis?analysis?

Bi l i lBi l i lBiological.Biological.

We will examine how at this level We will examine how at this level “we” take in information: organize, “we” take in information: organize, interpret, and store it; and use it.interpret, and store it; and use it.

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Neuron = Nerve CellNeuron = Nerve Cell--processes and transmits informationprocesses and transmits information

Efferent Neuron = Motor NeuronEfferent Neuron = Motor Neuron(innervates muscles or other organs)(innervates muscles or other organs)

Afferent Neuron = Sensory NeuronAfferent Neuron = Sensory Neuron(receives information from sense organs)(receives information from sense organs)

Interneuron = Interneuron = (sends and receives information between neurons)(sends and receives information between neurons)

How do these nerve cells How do these nerve cells exchange information?exchange information?

Electrochemically.Electrochemically.––Between neurons, a signal travels Between neurons, a signal travels

chemically.chemically.––Within the neuron a signal travels Within the neuron a signal travels Within the neuron, a signal travels Within the neuron, a signal travels

“electrically” via the movement of ions.“electrically” via the movement of ions.

How to neurons communicate How to neurons communicate with each other?with each other?

––Neurons are not physically joined Neurons are not physically joined together.together.

––Therefore how do they pass a signal Therefore how do they pass a signal across a physical space known as a across a physical space known as a p y pp y psynapse.synapse.

The word "synapse" comes from Greek: "The word "synapse" comes from Greek: "synsyn" " meaning "together" and "meaning "together" and "hapteinhaptein" meaning "to " meaning "to clasp."clasp."

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“You are your “You are your synapses.”synapses.”y py p

--Joseph Le Joseph Le DouxDoux

How Neurons CommunicateHow Neurons CommunicateNeurotransmittersNeurotransmitters (NT)(NT)–– Released from the axon terminal buds.Released from the axon terminal buds.–– Cross synapse.Cross synapse.–– Connect to correct receptorConnect to correct receptor--channels on channels on

dendritesdendritesdendritesdendrites–– Unlock Unlock channels at the receiving site allowing channels at the receiving site allowing

Na+ ions Na+ ions into the receiving neuroninto the receiving neuron..

How Neurons CommunicateHow Neurons CommunicateTwo Categories of Neurotransmitters (NT)Two Categories of Neurotransmitters (NT)

–– Excitatory: allow positive Na+ Excitatory: allow positive Na+ ions allowed in ions allowed in causes firingcauses firing

–– Inhibitory: allow negative Inhibitory: allow negative ions allowed in ions allowed in Inhibitory: allow negative Inhibitory: allow negative ions allowed in ions allowed in prevents firing prevents firing

Examples:Examples:–– ACh ACh (acetylcholine): excitatory NT(acetylcholine): excitatory NT–– GABA: GABA: inhibitory NT inhibitory NT –– keeps brain calmed keeps brain calmed

down and not firing out of controldown and not firing out of control

DRUGSDRUGS

Every drug Every drug that that affects affects behavior behavior works at the synapseworks at the synapse––Agonist: Agonist: excite the receiving neuron. excite the receiving neuron.

They are similar enough the NT that it They are similar enough the NT that it They are similar enough the NT that it They are similar enough the NT that it mimics its effects.mimics its effects.They block the reuptake of the NT in the They block the reuptake of the NT in the synapsesynapse

––Antagonist: Antagonist: inhibit the receiving neuron.inhibit the receiving neuron.They can block receptor site, block release They can block receptor site, block release of NT from sending neuron.of NT from sending neuron.

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ExamplesExamples

Curare:Curare:––Stops Stops AChACh from fitting into receptor from fitting into receptor

sites (used by natives on poison dartssites (used by natives on poison darts))Botox aka Botox aka BotulinBotulinBotox aka Botox aka BotulinBotulin––Blocks the release of Ach from the Blocks the release of Ach from the

sending neurons (paralysis)sending neurons (paralysis)Black Widow venom:Black Widow venom:–– Is similar to Ach Is similar to Ach and activates receptor and activates receptor

sites (seizures sites (seizures and convulsionsand convulsions))

DRUGS cont.DRUGS cont.

Dopamine (NT): excessive levels in Dopamine (NT): excessive levels in the brain associated with the brain associated with schizophrenia and low levels schizophrenia and low levels associated with Parkinson’s diseaseassociated with Parkinson’s diseaseassociated with Parkinson s diseaseassociated with Parkinson s disease––ThorazineThorazine

used used for schizophrenia patients b/c it blocks for schizophrenia patients b/c it blocks dopamine (antagonist)dopamine (antagonist)

–– LL--DopaDopa used for used for ParkinsonsParkinsons (agonist)(agonist)Patients develop tolerancePatients develop tolerance

DRUGS cont.DRUGS cont.

Endorphins: natural pain killing NTEndorphins: natural pain killing NT––Toughens the membrane of Toughens the membrane of

neurotransmitter sacs preventing them neurotransmitter sacs preventing them from breakingfrom breakingo b ea go b ea g

Pain signal is stoppedPain signal is stopped

––Morphine and other opiates: Morphine and other opiates: mimics mimics endorphins (agonist)endorphins (agonist)

Seratonin (NT)Seratonin (NT)

––Low levels associated with depressionLow levels associated with depression––Administer prozac Administer prozac –– prevents reuptake prevents reuptake

(agonist)(agonist)––M.A.O.’s breakdown seratoninM.A.O.’s breakdown seratoninM.A.O. s breakdown seratoninM.A.O. s breakdown seratonin––S.S.R.I. (selective seratonin reuptake S.S.R.I. (selective seratonin reuptake

inhibator) inhibator) M.A.O. inhibitors help seratonin (agonist)M.A.O. inhibitors help seratonin (agonist)

QuestionsQuestions

With so many NTs, are some found With so many NTs, are some found only in certain places?only in certain places?

H d th ff t d i H d th ff t d i How do they affect mood, memories, How do they affect mood, memories, and mental abilities?and mental abilities?

Can we boost or diminish these effects Can we boost or diminish these effects through drugs or diet?through drugs or diet?

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PathwaysPathways

Certain pathway uses 1 or 2 NT’s and Certain pathway uses 1 or 2 NT’s and that NT has a particular effect on a that NT has a particular effect on a behavior and emotion.behavior and emotion.


Electrochemically.Electrochemically.––Between neurons, a signal travels Between neurons, a signal travels

chemically.chemically.––Within the neuron a signal travels Within the neuron a signal travels Within the neuron, a signal travels Within the neuron, a signal travels

“electrically.”“electrically.”We are going to go backwards to see We are going to go backwards to see the process.the process.Question: What makes the NTs Question: What makes the NTs release from the axon terminals?release from the axon terminals?


Question 2: Where does this electric Question 2: Where does this electric message come from?message come from?It’s the movement of ions (charged It’s the movement of ions (charged particles) across the cell membrane particles) across the cell membrane particles) across the cell membrane particles) across the cell membrane of the axon.of the axon.This movement is called an This movement is called an

action potential.action potential.

Neural Impulse or Action PotentialNeural Impulse or Action Potential

Worth Archive VideoWorth Archive Video

Video Animation of an Action PotentialVideo Animation of an Action Potential

Another more detailed lessonAnother more detailed lessonAnother more detailed lesson.Another more detailed lesson.

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Resting potentialResting potential::–– Ratio of Ratio of

2 Positively 2 Positively charged charged K+ K+ atoms insideatoms inside3 Positively 3 Positively charged charged Na+ Na+ atoms atoms outsideoutside

––Therefore outside the neuron it is Therefore outside the neuron it is Therefore, outside the neuron, it is Therefore, outside the neuron, it is positively charged and positively charged and

–– inside the neuron, it is negatively inside the neuron, it is negatively charged (charged (--70 mV)70 mV)

In other words, the neuron is In other words, the neuron is polarized.polarized.


Action Action potential:potential:–– Positive Na atoms rush in and trigger a domino Positive Na atoms rush in and trigger a domino

effect down the effect down the axon. The region inside axon. The region inside becomes slightly positively charged.becomes slightly positively charged.

In other words the cell becomes In other words the cell becomes In other words, the cell becomes In other words, the cell becomes depolarized.depolarized.And guess what? It’s like dominoes. And guess what? It’s like dominoes. Once it starts, it can’t be stopped.Once it starts, it can’t be stopped.––This is called the allThis is called the all--oror--none principle.none principle.


Refractory period:Refractory period:–– A period of time when the neuron must A period of time when the neuron must

become polarized againbecome polarized again–– In other words…In other words…

Positive Na atoms go back outPositive Na atoms go back out–– Positive Na atoms go back outPositive Na atoms go back out

*Can happen 1000 times per second*Can happen 1000 times per second

Question…Question…

Question: What starts the action Question: What starts the action potential down the axon?potential down the axon?Demonstration perhaps?Demonstration perhaps?

This is our answer.This is our answer. Question…Question…

Question: What starts the action Question: What starts the action potential down the axon?potential down the axon?Demonstration perhaps?Demonstration perhaps?A Th ll b d d A Th ll b d d Answer: The cell body and axon Answer: The cell body and axon hillock are like a water gun, clown’s hillock are like a water gun, clown’s mouth, and a balloon.mouth, and a balloon.In other words, it’s an adding In other words, it’s an adding machine.machine.

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A Little (New) OrderA Little (New) Order

1.1. Get into groups of 3 or 4Get into groups of 3 or 42.2. I will give you an envelope.I will give you an envelope.3.3. It contains events and ideas It contains events and ideas

i l i l i tii l i l i tiinvolving neural communication.involving neural communication.4.4. Put them in the correct Put them in the correct

chronological order.chronological order.5.5. Some terms may or may not fit.Some terms may or may not fit.

Keep these in mind…Keep these in mind…

DepolarizationDepolarizationAllAll--oror--none principlenone principleDirection of impulseDirection of impulseRefractory periodRefractory periodThresholdThresholdResting potentialResting potentialAction potentialAction potential

Level of AnalysisLevel of Analysis

From the molecular and cellular level From the molecular and cellular level

TissueTissueOOOrgansOrgansOrgan SystemsOrgan Systems

Neural Chain (radio)Neural Chain (radio)1.1. Receptor Cells (antennae):Receptor Cells (antennae):

-- Skin on fingersSkin on fingers2.2. Sensory cells (wires connected to radio)Sensory cells (wires connected to radio)

-- Send impulse to brainSend impulse to brain3.3. Interneuron cells (radio)Interneuron cells (radio)

-- brainbrain4.4. Motor cells (wires to speaker)Motor cells (wires to speaker)

-- Back down arm to handBack down arm to hand5.5. Effector cells (speaker)Effector cells (speaker)

-- Control muscles that retract fingersControl muscles that retract fingers

Reflexes caused by inter-neurons in the spinal cord (demos)

Central Nervous SystemCentral Nervous System

Neural Neural Networks form from learning and Networks form from learning and practicepractice–– Increases the speed messages are Increases the speed messages are sentsent

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http://www.youtube.com/watch?http://www.youtube.com/watch?v=DF04XPBj5ucv=DF04XPBj5uc You versus a computerYou versus a computer

40 billion neurons 40 billion neurons X X

10,000 connections/neuron 10,000 connections/neuron = =

400 trillion synaptic connections!!!400 trillion synaptic connections!!!

Level of AnalysisLevel of Analysis

From the molecular and cellular level From the molecular and cellular level

TissueTissueOOOrgansOrgansOrgan SystemsOrgan Systems

Lou GehrigLou Gehrig

http://www.youtube.com/watch?v=ahttp://www.youtube.com/watch?v=a4msaZTJrTA4msaZTJrTA

Amyotrophic Lateral SclerosisAmyotrophic Lateral Sclerosis

6 out of 100,000 people usually 6 out of 100,000 people usually between ages 60 to 75between ages 60 to 75Death within 5 yearsDeath within 5 yearsR D th f t R D th f t Reason: Death of motor neurons.Reason: Death of motor neurons.Possible causes:Possible causes:––Death of microtubules in those axonsDeath of microtubules in those axons––Buildup of toxic chemicals within Buildup of toxic chemicals within

neuronsneurons––Toxic chemicals from other neuronsToxic chemicals from other neurons

DIVISIONS OF THE NERVOUS DIVISIONS OF THE NERVOUS SYSTEMSYSTEM

Central Nervous SystemCentral Nervous System–– brain and spinal brain and spinal cord cord ––billions of neuronsbillions of neuronsP i h l N S tP i h l N S tPeripheral Nervous SystemPeripheral Nervous System––Sensory and motor neurons that Sensory and motor neurons that

connect the brain to the rest of the connect the brain to the rest of the bodybody––A few millions for each.A few millions for each.

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DIVISIONS OF THE NERVOUS DIVISIONS OF THE NERVOUS SYSTEMSYSTEM

NERVOUS SYSTEMNERVOUS SYSTEM

PERIPHERAL PERIPHERAL CENTRALCENTRALPERIPHERAL PERIPHERAL CENTRALCENTRAL

AUTONOMIC SOMATICAUTONOMIC SOMATIC

SYMPATHETIC PARASYMPATHETICSYMPATHETIC PARASYMPATHETIC

Peripheral Nervous System Peripheral Nervous System (2 components)(2 components)

Somatic Nervous System:Somatic Nervous System:–– voluntary control of skeletal musclesvoluntary control of skeletal musclesAutonomic Nervous System:Autonomic Nervous System:

t l th l d d l f t l th l d d l f –– controls the glands and muscles of controls the glands and muscles of internal organsinternal organs

Sympathetic nervous system Sympathetic nervous system arouses (3 F’s)arouses (3 F’s)Parasympathetic nervous system Parasympathetic nervous system calmscalms

Tell me what’s happening within Tell me what’s happening within your nervous system.your nervous system.

Tell me what’s happening within Tell me what’s happening within your nervous system.your nervous system.

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Neural Chain (radio)Neural Chain (radio)1.1. Receptor Cells (antennae):Receptor Cells (antennae):

-- Skin on fingersSkin on fingers2.2. Sensory cells (wires connected to radio)Sensory cells (wires connected to radio)

-- Send impulse to brainSend impulse to brain3.3. Interneuron cells (radio)Interneuron cells (radio)

-- brainbrain4.4. Motor cells (wires to speaker)Motor cells (wires to speaker)

-- Back down arm to handBack down arm to hand5.5. Effector cells (speaker)Effector cells (speaker)

-- Control Control muscles that retract muscles that retract fingersfingers

ReflexesReflexes

ReflexesReflexes

http://www.youtube.com/watch?v=Qhttp://www.youtube.com/watch?v=QmNQdLkkJHM&NR=1mNQdLkkJHM&NR=1

Central Nervous SystemCentral Nervous System

Neural Neural Networks form from learning and Networks form from learning and practicepractice–– Increases the speed messages are Increases the speed messages are sentsent

Class exampleClass exampleClass exampleClass example

You versus a computerYou versus a computer

40 billion neurons 40 billion neurons X X

10 000 ti / 10 000 ti / 10,000 connections/neuron 10,000 connections/neuron = =

400 trillion synaptic 400 trillion synaptic connections!!!connections!!!

You are complexYou are complex

Neurons Neurons Reflex arcsReflex arcsNetworks Networks Networks Networks

Pathways Pathways Specialized regions Specialized regions

Brain Systems Brain Systems The BrainThe Brain

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ExitExit

On a strip of paper, On a strip of paper, ––write down one question write down one question you have from today’s you have from today’s you have from today s you have from today s lecture and lecture and

––drop it off in the black tray drop it off in the black tray by the door.by the door.

QuestionQuestion

What do you think has more lasting What do you think has more lasting effects?effects?

A text that reads “143” OR A text that reads “143” OR The Endocrine SystemThe Endocrine System•• Glands Glands that that

produce produce hormones that hormones that travel through travel through the body to the body to yyaffect certain affect certain tissuestissues

•• Pituitary Pituitary gland gland (master gland(master gland))

The Endocrine SystemThe Endocrine SystemNT’s and hormones NT’s and hormones

are chemically are chemically similar if not the similar if not the same.same.

Feedback System:Feedback System:Brain Brain (Hypothalamus) (Hypothalamus) pituitary pituitary other other glands glands hormones hormones

brain brain behaviorbehaviorE.g.: pubertyE.g.: puberty

Education

Module 4 handouts