Mod 17 (part 1)

Early Adulthood Overview

• Early adulthood typically occurs in the 20s and 30s.

• Key physical aspects:

  • Muscular strength, reaction time, sensory keenness, and cardiac output peak in mid-20s.

Middle Adulthood

• Range of physical vigor during middle adulthood varies significantly among individuals.

• Physical vigor is more dependent on health and exercise rather than age.

  • Regular exercise can mitigate physical decline.

• Physical changes:

  • Fertility Decline: Led by biological maturation.

    • Women experience menopause.

    • Men face gradual declines in sperm count, testosterone levels, and erectile function.

  • Sexual activity remains satisfying but may occur less frequently.

Late Adulthood

• Life Expectancy Trends:

  • 1950 to 2015: Global life expectancy surged from 50 to 73 years.

  • 13% of the world population is now aged 60 or older.

  • Women generally outlive men by about 4.4 years.

Theories on Aging and Longevity

• Telomere Theory:

  • Telomeres, located at the ends of DNA, shorten with cell division and potential premature aging.

  • Influenced negatively by smoking, obesity, and stress.

• Chronic stressors like anger and depression can raise the risk of premature death.

• Positive health habits can contribute to longevity.

Life Expectancy Data (2019)

• Life expectancy in various countries:

  • China: 76 years

  • US: 79 years

  • UK: 81 years

  • Canada: 82 years

  • Australia: 82 years

• Recent challenges like the opioid crisis and COVID-19 have impeded these gains.

Physical Changes in Late Adulthood

• Sensory declines:

  • Decrease in visual sharpness, distance perception, and adaptation to light.

  • Muscle strength, reaction time, speed, stamina, smell, hearing, and touch deterioration.

• Weakened immune system leads to increased susceptibility to diseases.

• COVID-19 highlighted vulnerability in older populations.

Cognitive Changes

• Aging Brain:

  • Memory-related brain regions may atrophy.

  • Breakdown of the blood-brain barrier starts in the hippocampus.

• Neuroplasticity exists; engaging the brain supports connections and cognitive health.

• Regular exercise benefits overall brain health by:

  • Enhancing blood flow, reducing shrinkage, maintaining telomeres, and encouraging neurogenesis.

Adult Cognitive Abilities

• Aging can affect memory, intelligence, and creativity patterns, with variability across individuals.

• Research methods to study cognitive changes:

  • Cross-sectional studies: Compare different age groups.

  • Longitudinal studies: Same individuals over time.

• Early adulthood is generally the peak for learning and memory retention.

• Prospective memory (e.g., remembering to take pills) is particularly important as we age.

Memory Trends in Older Adults

• Older adults may experience:

  • Decreased name recall but improved retrieval with cues.

  • Challenges with habitual tasks and word retrieval (tip of the tongue phenomenon).

• Study data indicates:

  • Decrease in names recalled is noted in cross-sectional analysis.

  • Number of recalled words tends to decline with age while recognition remains stable.

• Importance of education and mental challenges in maintaining cognitive function in later life.

  • Brain exercises improve specific related tasks but have limited transfer to unrelated areas.

• Terminal decline noted when memory becomes particularly faulty close to the natural death timeframe.

Conclusion

• Overall, aging presents a complex picture with both declines in certain physical and cognitive areas and potential for continued learning and memory retention.