Outline BB rain Anatomy SS tructures and functions DD isorders caused by lesions CC omparative...

Outline

Brain Anatomy Structures and functions Disorders caused by lesions Comparative Anatomy

Brain Function Cells in the brain How brain cells communicate

Drugs on the Brain Mechanisms of action Drug addiction

Or Lateral Sulcus

Structural Anatomy

Functional Anatomy

Executive Function

Functional Areas of the Brain

Language

WERNICKES AREA:LANGUAGE

COMPREHENSIONBROCA’S AREA:LANGUAGE

PRODUCTION

Wernicke’s Aphasia

Broca’s Aphasia

Two Interconnected Hemispheres

Split-Brain Phenomenon

Internal Structures of the Brain

Internal Structures of the Brain

VENTRICULAR SYSTEM

Comparative Anatomy:Structure = Function

Brain structure tells us a lot about how smart an organism is, how it

interacts with the world, etc.

RAT BRAIN

CAT BRAIN

PIG BRAIN

MONKEY BRAIN

Neurons: Cellular Communicators

DENDRITES

NUCLEUS

CELL BODY

AXON

MYELIN SHEATH

AXON TERMINALS

Electrical Signal Action Potential

Chemical Signal Neurotransmitter

Release Receptor Binding

Neurons: Cellular Communicators

Neurons Form Networks

Action Potential

Cellular Communication:

Sensory Acuity

Sensory Cortex

Sensory Units

To Sensory Cortex

Receptive Fields

Two-Point Discrimination

• Pick a partner• Have them close their eyes• Use paperclip (unfolded) to activate two

sensory receptive fields• Decrease distance between points until only

once sensory receptive field is activated– Arm– Hand– Back

• Record the distance between the points to get a rough estimate of regional sensitivity

Two-Point Discrimination

• Which area was most sensitive?• Which are was least sensitive?• What does this tell you about the sensory

receptive field size of each area tested?

Drugs of Abuse

How do drugs like nicotine and alcohol affect the brain? Why do these drugs produce a

“high” while other drugs that act on the brain (such as asprin) don’t have this effect?

Drugs Hijack Brain Pathways(endogenous vs exogenous ligands)

Example: Dopamine Reward Pathway

Cocaine Increases “Reward” Signal

Mechanisms (Simplified)

• http://learn.genetics.utah.edu/content/addiction/drugs/mouse.html

What is tolerance?

Tolerance occurs when you are abusing a substance/drug and over time your sensitivity to that substance decreases.

Higher quantities of the substance/drug must be consumed in order to achieve the same effects as before.

For example, a person has to drink more alcohol to reach a “buzz” than when he/she started drinking for the first time.

What is physical dependence?

Dependent upon a substance/drug to have normal function.

Develop negative withdrawal symptoms when the substance/drug is no longer on board.

Withdrawal symptoms are basically the opposite of the drug effects Withdrawal from stimulants: depression, lethargy Withdrawal from depressants: anxiety, sleeplessness

What is a standard drink?

What is Moderate Drinking?

Women Men

Moderate Drinking (“Low Risk”) Per Day

3 or less 4 or less

Moderate Drinking (“Low Risk”) Per Week

No more than 7 drinks

No more than 14 drinks

Heavy drinking would be considered consuming more than the daily amount or weekly amount listed in the table.

Alcohol Effects: Chronic Use

Normal “Happy” Brain

Your brain wants to compensate

Alcohol on the Brain

Your brain wants to compensate

Alcohol Withdrawal

What is considered a binge?

Binge drinking is consuming so much alcohol that your blood alcohol concentration (BAC) reaches 0.08g/dl or higher within 2 hours.

For women: 4 drinks or more within 2 hours

For men: 5 drinks or more within 2 hours

Withdrawal symptoms increase in severity after multiple relapses

Alcoholism can cause loss of brain matter over time

Impaired Brain Activity in Alcohol Dependence

Questions?