Biological Myths of Aging

•Memory declines drastically with age for all people.

•IQ declines drastically with age in all people.

•Learning becomes more difficult as we get older.

•There is nothing you can do counter these aging deficits.

Physical Decline with Aging

Nervous System

Decline with Age

•Decrease in brain size/weight•steady, slow, and mild

•Decrease in Brain blood flow

•Decrease in the use of Glucose

•Decrease in Sensory Systems

Brain Weight and Aging

Senses Decline with Aging

Memory Decline with Aging

Age-Related Deficits:•long-term memory•physical-motor tasks•free recall learning

•requiring conscious recollection and effort

No Age-Related Deficits:•short-term memory•non physical-motor tasks •recognition learning

•easily organized task structures or cues

Recall and Recognition in Adulthood

•Recognition •stable

•Recall•declines

Intelligence and Aging

Reducing Cognitive Decline1. Live in Favorable Environmental Circumstances

above-average educationhigh complexity occupationsabove-average incomemaintaining intact families

2. Be involved in activities typical of complex and intellectually stimulating environments

extensive readingtravelattending cultural eventscontinuing education activitiesparticipation in clubs and professional associations

3. Be married to a spouse with high cognitive status

Conclusion•Only certain types of memory show declines with aging.

•IQ does not show a drastic decline with age.

•The ability to learn does not deviate much as we get older.

•There is plenty you can do counter aging deficits.

•Stop smoking•Exercise regularly•Eat properly•Engage in learning activities•Stay in touch with friends, families, communities

Dementia

•Cognitive disorder that involves a gradual deterioration of brain functioning that affects judgement, memory, language, and other cognitive processes

• Caused my several different medical conditions (Alzheimer's, Parkinson's, Huntington’s, syphilis, stroke, HIV, head trauma) and by abuse of alcohol and drugs

Alzheimer's Disease: Symptoms

• memory impairment–starts slow and gradual–forget events, lose objects

• agnosia - can’t recognize objects

• aphasia - language problems

• apraxia - motor problems

• emotional changes–aggressive, agitated, public displays, wandering

• average survival is 8-10 years

Alzheimer's Prevalence

by Age

Alzheimer's: Biology

• chromosomes 1, 14, 19, and 21

• general brain atrophy

• neuronal degeneration

• decreased cerebral metabolism

• general decay of acetylcholine system– especially in the basal forebrain

• neurofibrillary tangles

• beta-amyloid plaques

General Brain Atrophy

Neuronal Degeneration

Normal Alzheimer’s

Decreased Cerebral Metabolism

Alzheimer's Normal

Decay of Acetylcholine System

*

Neurofibrillary Tangles

Microtubules:•Provide structural support•Are pathways for:

•Nutrients•Waste products•Neurotransmitters

Made of Tubulin

In Alzheimer’s Disease:Excess Tau protein binds builds upTau binds with Tubulin and tangles the microtubules preventing them from properly functioning

Beta-Amyloid Plaque Formation

Key enzymes:•Alpha-secretase•Beta-secretase•Gamma-secretase

Beta-Amyloid Precursor Protein (APP)is cut or cleaved by these enzymesthree different protein fragments form

Protein fragments:

p3 alpha and gammaharmless

40 amino acid stringbeta and gammaharmless

42 amino acid stringbeta and gammaTOXIC

Beta-Amyloid Plaques

Tau Filaments

Beta-Amyloid Plaques

Pathology:

•Interferes with Ca2+ regulation

•Increases free radicals

•Stimulates mircroglia aggregation

•Increases inflammation

Alzheimer's: Treatment• nothing can correct the damage

• possible agents that slow the deterioration:– education– tacrine hydrochloride– estrogen replacement therapy– vitamin E– aspirin

• helping patients adjust to memory loss– memory wallet, key baskets, tags

Alzheimer's: Memory Tricks

Alzheimer's Cure?

• Vaccine?– using the beta-amyloid peptide fragments

• Gamma-Secretase Inhibitors?– to block the inappropriate cleavage of the

beta-amyloid precursor protein