Lecture 1: Introduction to cognitive aging

Question 1

When it comes to general aging, there is a decline in acuity of senses; what are the senses affected?

Answer 1

Vison
Audition
Somatosensory
Gustatory
Olfactory
Vestibular

Question 2

What are the reasons why visual acuity declines?

Answer 2

changes in our visual system which occur with normal aging
there are also a number of disorders that increase this in prevalence with age

Question 3

What is the sclera?

Answer 3

the white part of his eye

Question 4

What is the cornea?

Answer 4

surface of the eyeball

Question 5

What is an anterior chamber?

Answer 5

space between cornea and lens (filled with aqueous humour)

Question 6

What is the iris?

Answer 6

changes to the pupil size

Question 7

What are lens?

Answer 7

changes shape to focus light rays on retina

Question 8

What is vitreous humor?

Answer 8

maintains shape of eyeball

Question 9

What is within the retina?

Answer 9

Rods: night visions
Cones: day & colour vision

Question 10

What are some examples of age-related changes in vision?

Answer 10

cornea becomes thicker and less curved
anterior chamber become smaller; aqueous humorous may drain inadequately, causing increased intraocular pressure and glaucoma
iris colour fades and pupil diameter decreases
the lens: continues to grow, becomes less elastic, denser, and yellower this causes changes in colour vision (likelihood of presbyopia increases
vitreous humour becomes more liquid. loose cells may cause shadows; retina: vessels & capillaries narrow, loss & change in chemical sensitivity of rods & cones

Question 11

What is Arcus senilis?

Answer 11

gray ring that forms around the edge of the cornea.
Arcus senilis is caused by fat lipid deposits deep in the edge of the cornea. It does not
affect vision, nor does it require treatment

Question 12

What do age related changes mean for decreased visual acuity?

Answer 12

changes in refraction by cornea & lens
* decreased accommodation ability
* less light admitted due to smaller pupils
* reduced number of rods & cones
* Decreased light/dark adaptation.
* Higher visual threshold (minimum light required
to stimulate receptors).

Question 13

What is aging?

Answer 13

begins from birth

Question 14

What is senescence?

Answer 14

the final stage(s) of the normal lifespan

Question 15

What are the ages within older adulthood?

Answer 15

young old (65-74)
old-old (75-84)
oldest old (over 85)

Question 16

What are the three ways we define “old age”

Answer 16

Chronological, biological and psychological

Question 17

What are the 5 subfields of cognition?

Answer 17

Memory, executive function, language, numerical cognition and categorization & knowledge representation

Question 18

What are the three ways we can study cognition?

Answer 18

Standardized test, on-line studies (chronometric) and neuroimaging

Question 19

What is a standardized test and name example?

Answer 19

how we assess cognitive function: MMSE

Question 20

What is MMSE?

Answer 20

Mini Mental State Examination; a screen for dementia in multiple cognitive domains

Question 21

What are on-line studies and name examples?

Answer 21

use to measure the time to react to stimulus as well as response accuracy in tasks requiring cognitive processing: digit span, troop test, Boston naming test

Question 22

What is a digit span?

Answer 22

when you repeat numbers; forward test is for short term memory and backward test is for working memory

Question 23

What is a stroop test?

Answer 23

assessing inhibitory function

Question 24

what is a Boston naming test?

Answer 24

test of language function

Question 25

What is neuroimaging and provide example

Answer 25

medical images of the brain: fMRI & PET

Question 26

What is fMRI?

Answer 26

Functional Magnetic Resonance Imaging measures the hemodynamic response in the brain; the underlying assumption that oxygenated blood goes to areas where neural activity is occurring

Question 27

What is a PET?

Answer 27

Positron Emission Tomography detects the gamma rays emitted when the positron emitted from the radioactive substance collides with an electron in the tissue

Question 28

What are three research methods?

Answer 28

Human research, animal research, in vitro research

Question 29

Name advantages of human research

Answer 29

since the topic of interest is humans and we are using humans its the best
we can study systems that are difficult to study in animals/in vitro models
don’t need to worry about if findings will transfer to a human model

Question 30

List disadvantages of human research

Answer 30

the aging is very heterogenous across individuals; people can be the same age but look completely different, act completely
the gang is ver heterogeneous within individuals; some systems in the body age faster than others like your hearts in good shape but not your bones

Question 31

What are challenges in human research?

Answer 31

it is difficult to follow an individual from brith to death due to cost and attrition of subjects due to unwillingness to participate, illness, or death

there are ethical considerations that are grater with humans than in vitro or animal research such as experimental approaches that are unethical for humans but good In other cases
some approaches also need to be tested first in animals/in vitro before humans (gene therapy)

Question 32

Why do we use animals for studies?

Answer 32

the aging process is much faster and we can build models and perform studies we can’t do in humans

Question 33

How do we choose a species and what are some examples we can choose from?

Answer 33

have to factor in your research question, select species that have a particular feature of interest, often in an exaggerated form; genetics in mice, opossum for fast aging rate, canine models for AD

Question 34

What are some considerations in animal research?

Answer 34

specificity: the model must exhibit trait of interest, generalizability/transferability: the results observed in the chosen model must be applicable to other species, feasibility: the availability, cost, convenience of the model must be reasonable

Question 34

Why do we use in vitro cells/tissue?

Answer 34

can examine cell properties at different ages
cultured cells can serve as model for identifying specific cell functions or mimicking aging pathologies

Question 35

Why use birds, bats and naked mole rats?

Answer 35

live longer than humans in terms of the amount of oxygen processed
ties into major theory of aging, free radical theory
great species for assessing interventions based on free radical theory

Question 35

What is the hayflick limit?

Answer 35

hay flick observed that cells dividing in cell culture divided about 50 times before dying; the number of times our cells can divide before experiencing the senescence phase; as cells approach the limit they show more signs of old age

Question 35

What are the advantages and disadvantages of in vitro?

Answer 35

easy to control confounding variables
however, we don’t know how well the results in vivo; just because in works in cells doesn’t mean it will work the same in animals/humans