Brain & Behavior

Psychology OneFall 2002 - OLDHinsdale South H.S.

ANNOUNCEMENTS

- Keep reading Unit III on Brain pg 94-110- The entire outline through 121- Outline Due MONDAY

- TEST MAKEUPS BY MONDAY!

WHY STUDY THE BRAIN IN PSYCHOLOGY? WHAT HAPPENS TO CUTLER’S BRAIN WHEN HE IS

SACKED?

Fact:

Men’s brains are not fully developed until age 22 while girls develop sooner. Why?

See packet (Men’s vs. Women’s Brains)

Figure 2.7 The functional divisions of the human nervous systemMyers: Psychology, Eighth EditionCopyright © 2007 by Worth Publishers

Single Neuron (see packet for diagram)

1.Dendrites2.Cell Body (Soma)3.Nucleus4.Axon5.Glial Cells6.Nodes of Ranvier7.Covering = Myelin Sheath8.Terminal (Axon) Buttons 9.Terminal Branch

The Neuron

What is it? Cells of nerve tissues where messages travel to and from

the brainWhere are they found? Everywhere in your body! You have millions of them!What type of communication happens here? Electrical Action Potential Chemical

Parts of the Neuron

Cell Body Nucleus AxonTerminals

or Terminal Buttons

Synapse

Myelin Sheath

AxonNodes of Ranvier

Dendrites

Terminal Branch

Neuron PartsNucleus - Brain (converts chemical messages to electrical

messages)Cell Body - Houses the nucleus, vesicles that carry

neurotransmitters to the axon terminal are produced here.

Myelin Sheath - Fatty, insulation, which protects the axon and

speeds impulses (Glial Cells help repair)Nodes of Ranvier – Breaks in the meylin sheath where depolarization

occurs;

Neuron Parts Axon – Fibers that carries electrical impulses Away from the cell body. Electrical impulses travel down the axon as depolarization

happens at each Nodes of Ranvier. Depolarization happens multiple times along the axon.

As the action potential moves, vesicles are carried closer to the axon terminal.

Dendrites – Fibers that receive neurotransmitters (chemical

communicators) from other neurons At the cell body, the chemical message is downloaded and is

translated into an electrical impulse which then travels down the axon.

Receive messages like a Post Office

Neuron Hand Model

Fingers = Dendrites Palm = Cell Body Dot = Nucleus Arm = Axon Skin = Myelin Sheath Elbow = Terminal Button

ALONG THE AXON:

Action Potential – A brief electrical charge that travels down the axon like a domino effect, one triggers the next. Happens very quickly.

Resting Potential – When the axon is waiting to be fired. Sodium on outside and Potassium on the inside. (SALTY BANANA)

ALONG THE AXON

Depolarization-As the AP moves down the axon, this is the

process of the positively charged sodium particles to move inside the axon and the negatively

charged potassium particles move outside the axon. This occurs at the nodes of ranvier.

Refractory Period- After depolarization or the firing of an action

potential, the sodium returns to the outside of the axon and the potassium returns to the inside.

Depolarization

Figure 2.3 Action potentialMyers: Psychology, Eighth EditionCopyright © 2007 by Worth Publishers

The SynapseDefinition: The space between the

axon terminal and the next dendrite.

Sends chemical messages called, neurotransmitters, to the next neuron.

Vesicles are balloon like structures that carry neurotransmitters to the synaptic gap.

Axon Terminal

Synapse

Dendrite

Vesicles

ActionPotential

Neurotransmitter

DockingSite

Things to Remember About a Neuron Firing!

1. All or none response – a neuron either fires or does not. There is no partial firing.

2. Threshold – to get a neuron to fire, there is a threshold of neurotransmitters that must be met in

order for a neuron to fire.

3. Lock and Key – There are certain receptor sites for specific neurotransmitters.

Figure 2.4 How neurons communicateMyers: Psychology, Eighth EditionCopyright © 2007 by Worth Publishers

Chemical messengers called neurotransmitters enter receptor sites on the dendrites and cell body. This causes the cell membrane to open up and sodium ions to flow in. When there is enough of a positive charge, the neuron reaches threshold, and the first section of the axon opens up and sodium ions flow in. This exchange of sodium ions happens down the length of the axon. When the signal reaches the terminal branches at the end of the axon, neurotransmitters flow out into the empty space called the synapse.

A. Axon B. Dendrites C. Neurotransmitters D. Sodium ions B. E. Terminal branches

Why do we not have one big neuron running through out our body?

Can we slow and speed up our impulses? Give an example.

Will your leg or arm itch first and why?

Basic Reflex - SIM

1. Touch something hot

2. Skin receptors pick it up, sends it to sensory neuron that carries it to the spinal cord

3. The interneuron in the spinal cord translates it into an action.

4. Motor neuron carries message to finger to move it away from the flame.

5. DOES NOT GO TO BRAIN FIRST!!

Figure 2.9 A simple reflexMyers: Psychology, Eighth EditionCopyright © 2007 by Worth Publishers

FACTORS that effect Neurotransmitters

AGONISTS – mimics a neurotransmitter or stops reuptake

ANTAGONISTS – speeds up reuptake or stops production of neurotransmitter.

Excitatory – (speeds up or continues communication) agonist

Inhibitory – (slows down or stops, antagonist

Table 2.1Myers: Psychology, Eighth EditionCopyright © 2007 by Worth Publishers

Announcements / Review

Review! What is the difference between agonist and antagonist? Neurotransmitters associated with Schizophrenia,

Alzheimers, Depression? REUPTAKE, Depolarization, Neuron Parts Thalamus, Sensory Cortex, Left hemisphere Phineas Gage? Huntington’s Disease? Broca’s and Wernicke’s Areas General Region of Parts QUIZ THURS ON NEURON AND BRAIN EC? BRAIN DAMAGE GAME THURS!

The Brain

What is the outer most part of the brain called? There are three names for it!

Lobes of the BrainOccipital Lobe – (visual cortex

located within)

VisionParietal Lobe – Body SensationsFrontal Lobe – Working memory,

PersonalityTemporal Lobe – (auditory

cortex located within)

Hearing Temporal Frontal

Occipital

Parietal

Primary SomatosensoryCortex

Primary MotorCortex

The lobes are specific areas contained with in what part?

Sensory and Motor Corex

Sensory Cortex – is located in the Parietal Lobe, controls body sensations such as temperature, pressure and pain.

Motor Cortex – is located in the Frontal Lobe, Top controls your toes, bottom controls your head. Facial movement control takes up a lot of motor cortex.

Parts of the BrainCerebellum- Posture & Balance &

Coordination of Thinking

Cerebral Cortex – Contains 4 lobes, aka

forebrain & cerebrum

Corpus Callosum – Divides 2 hemispheres

Pituitary Gland Master gland of endocrine

system

Corpus Callosum

CerebralCortexForebrain

Hindbrain Midbrain

Spinal Cord

PituitaryGland

Cerebellum

Hypothalamus

Thalamus

What part of the brain would this rat’s car be hooked up to?

While this contraption looks similar to a doggy wheelchair or a pair of prosthetic legs for your favorite pet, it’s actually much more sophisticated. This rat is hooked up to a prototype of a thought-guided robot wheelchair.

http://blogs.discovermagazine.com/discoblog/2010/10/05/its-a-rat-its-a-toy-car-its-ratcar/

Hemispheres of the BrainLeft Verbal: speaking, understanding

language, reading, writing Mathematical Analytical: analyzing separate

pieces that make up a wholeRight Nonverbal: simple sentences &

words Spatial: art, geometry, facial

recognition Holistic: combining parts that

make up a whole

Other Areas Within LOBES Angular Gyrus – In the parietal lobe,

involved in a number of processes related to language, mathematics and cognition.

Gyrus – Ridges in the brain, more surface area for memory storage.

Broca’s Area– Left, Frontal Lobe, Production of Speech

Wernicke’s Area – Left, Temporal Lobe, Comprehension of Speech

The Endocrine System - Hormones Pituitary Gland – Master

Gland, HGH Thyroid – Metabolism Adrenal gland –

Adrenaline / Noradrenaline (epinephrine and norepinephrine)

Pancreas – Insulin Testes – Testosterone Ovaries – Progesterone

and Estrogen

LIMBIC SYSTEM

– controls emotions, contains four parts (midbrain), connected to frontal lobe! (PHINEAS GAGE)

Thalamus - The brain’s sensory switchboard, located on top of the brainstem or midbrain

Hypothalamus- Controls maintenance activities like drinking, eating, sexual arousal. (midbrain)

Amygdala = anger and fear (mid brain)Hippocampus = memory creation (mid brain)

HINDBRAIN / BRAIN STEMOld brain, most animals have this portion

Medulla – helps circulate spinal fluid, regulates autonomic functions.

Pons – respiratory functions.

Reticular formation – arousal.

Cerebellum – posture, movement and coordination of thinking.

Disorders of the Brain:Prosapagnosia = facial blindness

Aphasia = interference with speech, what 2 parts?

Blind Sight = failure to consciously see change but can subconsciously notice visual change.

Huntington’s Disease = decay of brain, late onset

Synestheisa = Crossing of Senses – See Colors for Sounds you hear. Taste Words.

THINGS THAT HELP OUR BRAIN: Plasticity – Rewiring the brain after an injury

Neural Networks – More synaptic connections = Better Memory

Long Term Potentiation – Memory = Quicker and more efficient neural firing.

WAYS TO STUDY THE BRAIN

Lesions – tiny areas of destruction

EEG – measures electrical signals / waves

CT – takes slice images of object

MRI – helps look at soft and hard surfaces like X-ray

PET – radioactive injection, brain glows with active parts (red active, blue not active)

LOBOTOMY

Which gives the best view of the brain?

Who is Phineas Gage?

Rail Road Worker Accident Survived! Showed us the

amazing capabilities of the brain!

See AP Edition Review Brain PPTFor practice questions

Practice Questions…. You are a pathologist in a large Northwestern city. You are conducting an autopsy on an

83-year-old male who was found dead in his home with no obvious cause of death. During the autopsy you discover the individual suffered two

strokes. Based on the functional information below provided by the next-of-kin, where were the two areas that suffered from the cerebral vascular

accidents? failure to do certain specific movements massive overeating disrupted circadian rhythms increased susceptibility to stress poor muscle tone discontinued secretion of gluccocorticoids inability to adjust heart rate unrestricted water loss in kidneys loss of control to react to body temperature changes failure of the respiratory system inability to do locomotion

Practice Questions….. At 1:30 am you (a trauma surgeon) are called for emergency surgery on a 17 year old

Caucasian female that was shot in the head during a drive-by shooting. After a tedious surgery, the patient remarkably remains alive and doing reasonably

well. The bullet traveled completely through the skull leaving a path of destroyed tissue behind it. You have decided to speak with the parents

about what noticeable changes will occur in their daughter due to the destruction of neural tissue. Based on the information below, determine the

approximate path the bullet traveled (i.e., what structures were damaged – keep in mind that it is possible for fragmenting and ricocheting of the bullet

resulting in somewhat unlikely combinations of areas effected). limb apraxia inability to control the muscular movements of the left shoulder, arm, forearm, and hand slow, laborious, nonfluent speech inability to sound out words and write them phonetically pure alexia difficulty finding appropriate words when speaking inability to use or recall nouns in speech and communication inability for sensory input to be recognized verbally poor word repetition decreased sex drive

Practice Questions……. Mr. Livingston is a 39 year-old African-American male who has been brought into your

neurology clinic by his wife. She has become increasingly alarmed regarding her husband’s health over the past four months. Upon completion of a

CT scan, it is determined that Mr. Livingston’s condition is the result of the presence of two tumors that have developed within his brain. Using the

patient history information listed below and the information from class and your textbook, determine where these two tumors are

probably located. muscle weakness vastly increased appetite (gained 25 lbs in the last three months) inappropriate body temperature fluctuations jerky movements decreased sexual desire poor balance when walking and standing increased frequency of urination inability to throw objects inappropriate sleep patterns (seems to fall asleep randomly during day and night) uncontrolled aggressiveness (rather violent, “short fuse”) exaggerated efforts to coordinate movements in a task

Practice Questions Answers Exercise 1: The two tumors are located in the hypothalamus and

the cerebellum.

Exercise 2: The damaged structures include: the right (primary motor cortex), the corpus callosum, Broca’s Area (left frontal lobe), and the left temporal gyrus.

Exercise 3: The stroke regions were the hypothalamus and the reticular formation.

Portable Brain Model

Limbic System – Emotions, personality Fight or Flight Response

Cerebellum – Body movement

Spinal Cord – Receives & sends messages

Cerebral Cortex – Left & Right Hemispheres

Neuron DemonstrationsBe sure to take notes on these to better your understanding!

Hershey Kiss Student Axon Neurotransmitters are

represented by kisses. Dark Kisses = Inhibitory

Signal = Slow Down Red Kisses = Excitatory

Signal = Speed Up Spray of water = release of

neurotransmitters from vessicles.