Post on 05-Jan-2016
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?