RESEARCH STRATEGIES

NEURAL & HORMONAL SYSTEMS

TOOLS OF DISCOVERY/BRAIN STRUCTURES

THE CEREBRAL CORTEX & OUR DIVIDED BRAIN

Modules 3-6

Research Strategies

Scientific Method *operational (objective) definitions *replicate the study *valid (tests what it is supposed to) *reliable (consistent results)

Correlation vs. Causation

Descriptive Correlational Experimental

Case Study (Collect data on 2 or more variables – no manipulation)

Laboratory Study

Naturalistic Observation

(Just observe and record – look for

(manipulate one or more factors)

Survey natural relationships.)

WORDING – IMPORTANT!RANDOM SAMPLE

POPULATION SIZE & MAKE-UP

CORRELATION COEFFICIENT(STRONG VS. WEAK)

(POSITIVE VS. NEGATIVE)

SCATTERPLOT (REVEALING)

More about research …

Experimentation

Control Group & Experimental GroupDependent Variable (depends on what you do to

the other one!)Independent Variable (manipulated by

researcher)Confounding Variables (other factors that can

impact results)Blind Study – participants don’t know if they get

the “treatment”Double Blind Study – participant and researcher

don’t know if participant gets “treatment”

STATISTICS (YEAH!! ! )

MEASURES OF CENTRAL TENDENCY (MEAN/MEDIAN/MODE)

MEASURES OF VARIATION(RANGE/STANDARD DEVIATION)NORMAL CURVE (BELL CURVE)

PAY SPECIAL ATTENTION TO PAGE 41

REMEMBER – DIFFERENCES MAY BE SIGNIFICANT BUT STILL NOT IMPORTANT.

*great summary on page 37.

I highly recommend!

REPRESENTATIVE SAMPLES ARE BETTER THAN BIASED SAMPLES

LESS-VARIABLE OBSERVATIONS ARE MORE RELIABLE THAN THOSE THAT

ARE MORE VARIABLE

MORE CASES ARE BETTER THAN FEWER

Just a bit more about statistics…

Module 4 – Biology…

Phrenology & Dr. GallNeurons – cell body, dendrite fibers (receive

information), axon fibers (send messages)“Dendrites Listen & Axons Speak”Myelin Sheath = insulator

No insulator = multiple sclerosis – degenerative loss of muscle control

~ Action potential – electrical impulse (2-180 mph)~ Threshold – if this is exceeded, the party’s on! All or nothing response, though. One neural impulse doesn’t get stronger - more neurons fire

Previous slide taken from:

http://www.kizoomlabs.com/products/the-adventures-of-ned-the-neuron/

Other images from: Google Images

Neurotransmitters

Synapse=meeting point between neurons

Neurotransmitters – chemical messengers. Enable the connections between neurons. When fired, neurotransmitters are released and connect (like lock & key) to another neuron. This excites (or inhibits) the continued firing of the message.

Reuptake is when the sending neuron reabsorbs the excess chemical.

Neurotransmitters, continued

Please look at the table on page 52 Endorphins – neurotransmitter similar to morphineDrugs/other chemicals affect brain chemistry by

exciting or inhibiting the firing of neurons. Agonist molecules – mimic neurotransmitters Antagonist molecules – inhibit/block transmitter functions

Read about Botulin (Botox) on page 53.

Nervous System

Previous slide taken from: http://www.rhsmpsychology.com/

I would recommend visiting this site. This instructor uses the same textbook and has some relevant handouts and study materials that may help you. ~I will let you know if I find helpful resources for you to use – if you find any, I would appreciate it it you would please share them with me.

Central Nervous System

Reflexes – a warm headless body can do it.

What about paralysis and sex?

Direct stimulation (reflex) vs. images/feelings…(mental)

Endocrine System and Hormones

Hormones – chemical messengers that travel in the bloodstream.

Sex/Food/AggressionSlower than neurotransmitters but some are

similar. If it takes time to effect you, also may take longer to dissipate. “Simmer Down”

In times of stress/danger – Autonomic Nervous System (ANS) tells adrenal glands to release epinephrine and norepinephrine (adrenalin/noradrenaline) ~ Raises BP, HR and blood sugar

GROWTH HORMONES

OXYTOCIN – AIDS BIRTH AND …

MASTER GLAND – IMPACTS OTHER GLANDS.

Pituitary Gland

EEG – ELECTROENCEPHALOGRAM

SHOWER-CAP-LIKE HAT FILLED WITH ELECTRODES & CONDUCTIVE GEL

NO DIRECT ACCESS TO BRAINSTIMULUS – SEE CHANGES DUE TO

STIMULUS

“LISTEN TO THE HUM”

Brain Scans

PET – POSITRON EMISSION TOMOGRAPHY

SHOWS BRAIN’S CONSUMPTION OF GLUCOSE – ACTIVE NEURONS EAT IT UP!

RADIOACTIVE GLUCOSE TRACKED BY MACHINE – SHOWS “HOT SPOTS” WHERE

BRAIN IS MOST ACTIVE

Brain Scans

MRI – MAGNETIC RESONANCE IMAGING

PERSON’S HEAD IS PUT IN A STRONG MAGNETIC FIELD THEN RADIO-WAVE

PULSE DISRUPTS ALIGNED ATOMS AND WHEN THE ATOMS RETURN TO A NORMAL SPIN, THEY PROVIDE A PICTURE OF THE SOFT TISSUES

Brain Scans

Brain Scans

fMRI – functional MRI

Where the brain is especially active, blood goes. Repeated MRI scans can show where the blood is

going as a patient performs different functions

Mind Reading?

Structures of the Brain

Brain StemCerebellum – base of skull – “little brain”

Nonverbal learning & memory Time / emotions Balance / walking / shaky hands

Limbic SystemAmygdala – aggression / fear

Hypothalamus –

hunger / thirst / body temp / sexual behavior

Module 6

Cerebrum=85% of brain’s weightCerebral Cortex – like the bark on a tree. “Thinking Crown”

Size of a large pizza Ultimate Control Center 20-23 billion nerve cells

300 trillion synaptic connections

4 lobes of the brain

FrontalParietalOccipitalTemporal

• ALL THESE INTERPLAY

Cortex

Motor Cortex – mapping brain activity – every thought is a neural event

Sensory Cortex – occipital lobe – sensory area – bash=blindness – stimulation=flashes of light (see stars)

Auditory Cortex – Schizophreniaauditory hallucinations seen via MRI

Association areas: stimulation doesn’t result in any observable response – more difficult to map

Phineas Gage – page 74

Plasticity – ability of brain to repair itself following injury.

NeurogenesisSplit Brains

We don’t know much about the brain!

Brain Damage

Sometimes brain can re-route pathways. Plasticity Neurogenesis Stem Cells May change personality

Everything psychological is also biological.