Week 2

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which theory suggests that ageing follows a biological timetable regulated by genetic processes?

Stochastic factors

Cellular theories

Programmed factors (correct)

Metabolic theories

What does the Hayflick limit refer to in relation to cellular theories of ageing?

The rate of metabolic damage accumulation

The maximum lifespan of an organism

The number of times a cell can divide (correct)

The ability of telomerase to replicate DNA

According to the metabolic rate of living theories, what is a primary factor that affects lifespan?

Metabolic speed (correct)

Social interactions

Genetic diversity

Increased physical activity

Which of the following best describes the role of telomeres in the ageing process?

They protect chromosomes from damage Signup and view all the answers

What is a major implication of telomerase activity in somatic cells?

It is typically not present, affecting cell longevity Signup and view all the answers

Which mechanism contributes to the stiffer tissues observed with aging?

Cross-linking Signup and view all the answers

How can programmed cell death be beneficial for other cells?

It provides building materials from cellular fragments Signup and view all the answers

What is the term used to define the expected duration of life under optimal conditions?

Longevity Signup and view all the answers

Which of the following genetic disorders is known for causing accelerated aging?

Werner's Syndrome Signup and view all the answers

Which of the following changes is typically associated with aging?

Decreased mobility Signup and view all the answers

What role does heritability play in the context of longevity?

It affects the likelihood of living a longer life Signup and view all the answers

The physiological changes in aging typically result in what kind of decline?

Functional decline Signup and view all the answers

Which of the following statements accurately describes the effect of aging on neurons?

Tangles develop in axon fibers. Signup and view all the answers

What is a significant consequence of free radicals in the context of aging?

They lead to cellular damage Signup and view all the answers

What is the primary function of white matter in the brain?

To transmit information between different parts of the brain. Signup and view all the answers

Which of the following is NOT a change in the brain associated with aging?

Increase in the number and size of dendrites. Signup and view all the answers

What is a potential consequence of white matter hyperintensities (WMH)?

Increased likelihood of stroke. Signup and view all the answers

What structural change occurs in the axon fibers as a result of aging?

Tangles develop in the axon fibers. Signup and view all the answers

Which neurotransmitter change is typically observed with aging?

Overall decrease in neurotransmitters. Signup and view all the answers

Which component of the brain is characterized by lesions appearing as bright spots on MRI scans?

White matter. Signup and view all the answers

Study Notes

Theories of Ageing

Non-stochastic (Programmed) factors indicate that ageing follows a biological timetable regulated by genetics.
Stochastic (Damage-related) factors suggest that ageing results from accumulated cellular damage due to metabolic by-products.
Metabolic theories propose that a faster metabolism correlates with a shorter lifespan, influenced by energy limits and hormonal adaptations.
Cellular theories include concepts such as the Hayflick limit, where cells can only divide a finite number of times; telomeres shorten with each division leading to instability in chromosomes.
Genetic programming theories suggest that ageing processes are coded into our genetics, resulting in pre-programmed cell death through apoptosis.

Genetics and Ageing

Genetic mutations can significantly impact longevity; a single mutation in worms can nearly double lifespan.
Heritability of longevity is notable, especially in offspring of long-lived individuals who tend to be less prone to age-related diseases.
Certain rare genetic disorders (e.g., Werner’s syndrome, Cockayne syndrome) can cause accelerated ageing, functioning at eight times the normal rate.

Definitions of Ageing

Ageing involves an exponential increase in mortality, physiological functional decline, and heightened vulnerability to diseases.
Life expectancy refers to average lifespan expectancy, while longevity represents life duration under ideal conditions. Lifespan denotes the typical duration for life events.

Physical Changes with Age

Appearance changes include alterations in skin, hair, voice, body build, and overall mobility.
Sensory system changes affect vision, hearing, balance, taste, and smell, impacting daily activities and quality of life.

Vital Systems

Ageing influences vital functions across various systems:
- Cardiovascular health declines.
- Respiratory diseases become more prevalent.
- The reproductive system undergoes notable changes.
- The autonomic nervous system is affected by age-related alterations.

Brain Changes with Age

Neuronal decline occurs, including reduced number and size of dendrites, formation of tangles in axon fibers, and increased protein deposits.
White matter hyperintensities (WMH) are lesions that increase with age, linked to dementia and strokes.
Neurotransmitter levels decrease, particularly dopamine, serotonin, and acetylcholine, leading to cognitive and emotional changes.
Brain structure shrinks notably in regions such as the prefrontal cortex and hippocampus, impacting memory and executive function.

Impacts of Brain Changes

Ageing impairs executive functioning and memory due to structural brain changes.
Emotional processing improves with age, leading to better emotional regulation.
The Parieto-Frontal Integration Theory (P-FIT) posits that intelligence arises from an interconnected network in the brain's parietal and frontal areas.

CRUNCH (compensation-related utilization of neural circuits hypothesis) suggests older adults use additional brain networks to maintain cognitive functions.
STAC-r (scaffolding theory of cognitive age revised) proposes that older adults develop strategies to compensate for cognitive decline through enhanced neural flexibility.

Summary of Learning Outcomes

Three theories of ageing encompass programmed, stochastic, and metabolic perspectives.
Key aspects of primary ageing include changes in appearance, sensory systems, and vital functions.
Psychological implications of ageing offer insights into cognition, emotion, and social interactions.
Primary ageing of the brain involves understanding neuronal changes, neurotransmitter decline, and structural impacts on cognitive abilities.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the key theories of ageing as discussed in Week 2 of the 3012PS course. This quiz covers the primary ageing factors impacting both the body and brain, including appearance, mobility, sensory changes, and vital systems. Engage in the psychological implications of these ageing processes.