People’s body development has different peculiarities for each period of adult life. Organ reserve ensures quick recovery after a stressful situation, works most effectively in emerging adulthood, and reduces each year (Berger, 2018a). Homeostasis also worsens with time; it maintains a balance between various physical functions in the short term (Berger, 2018a). Allostasis entails a durable adjustment which slowly influences overall physiology (Berger, 2018a). Therefore, an individual’s way of life and harmful habits in early adulthood may lead to adverse conditions later. Such a process, when negative effects accumulate and certain organ reserve is taken to preserve health, is called allostatic load (Berger, 2018a). For instance, if a person constantly suffers from insufficient sleep, their body adapts to such a regimen by decreasing energy, which eventually results in poor health outcomes over the years (Berger, 2018a). The same can be applied to nutrition: occasional overeating or undereating brings homeostatic reactions, but if such habits become persistent, the allostatic load increases and causes problems in middle and late adulthood (Berger, 2018a). Consequently, one should cultivate a healthy way of life since youth.
As a person becomes older, their body changes on all biological levels. Senescence deprives people of the ability to support homeostasis and makes them more susceptible to diseases (SciShow, 2012). While growing older, an individual needs more oxygen (Berger, 2018a). Its distribution into the lungs declines approximately four percent per decade upon turning twenty (Berger, 2018b). Quitting harmful habits and doing regular exercises is necessary to maintain the breathing function (Berger, 2018a). The brain also works slower with age, demonstrating lengthened reaction time because of decreased neurons and reduced myelination (Berger, 2018b). Nonetheless, growing dendrites reflect one’s experience, and a person performs certain repeated actions increasingly better (Berger, 2018a). Furthermore, people’s senses gradually subside over time (Berger, 2018b). For example, peripheral vision worsens before frontal, and hearing at high frequencies diminishes earlier than the one at low frequencies (Berger, 2018b). Growing older requires one to adjust to changes in their body and use the experience to mitigate unwanted effects.
To understand the causes of senescence, scientists have developed several theories of aging. One of them supports the principle of wear and tear: exposure to rigorous weather, environmental pollution, junk food, or radiation damages the human body (Berger, 2018d). However, it does not explain why older people can restore their health through physical activity. According to genetic theory, the speed of aging, the maximum life span, and partly diseases are determined by genes (Berger, 2018a). Nonetheless, overreliance on genetic predisposition may divert one’s attention from other reasons of health deterioration. Cellular aging focuses on the influence of stress and toxins on cells and molecules with the accumulation of errors in their reproduction (Berger, 2018a). The damage is easily fixed in emerging adulthood but becomes increasingly difficult for the immune system later in life when reaching the Hayflick limit and critical shortening of the telomeres in chromosomes (Berger, 2018a). Further research is needed to justify the theories of aging and take corresponding action.
Cognitive development in adulthood is characterized by advanced related processes. Following Piaget’s four stages, scientists describe the fifth – postformal thought, according to which individuals gain flexibility and become more practical (Berger, 2018a). People can combine formal analysis and quick reactions to solve problems proactively instead of avoiding them (Berger, 2018c). The special noted feature of emerging adulthood includes neurological advances. The boosted cognition depends on the socioeconomic status and culture, but most importantly, on peers (Berger, 2018a). Some parts of the brain in this period demonstrate improved mentalizing, which involves understanding the intentions and emotions of others (Berger, 2018a). It is believed that neurological maturation continues in early adulthood, which is seen in the increased myelination of the prefrontal and parietal lobes, allowing for better control of one’s impulses (Berger, 2018a). Thus, adult cognitive development helps individuals interact with each other in a mature way, considering possible consequences.
One’s intelligence in adulthood can be viewed from various perspectives. According to Spearman’s theory of general intelligence, it is a common factor encompassing all cognitive abilities, which vary for each person (Berger, 2018b). Another idea proposes different components of the concept – fluid and crystallized. The former category is quick and flexible, which allows adjusting to unfamiliar situations and includes working memory, speed of reasoning, and abstract thought (Berger, 2018b). The latter involves the accumulated learning, which can improve with age. For example, when two groups of different generations were given the same brain-teasing task, the older individuals were more successful in completing it because of gained knowledge and experience (Professor Ross, 2017). Sternberg accentuates analytical, creative, and practical types of intelligence. The first component focuses on abstract planning, strategic choice, logic, and information processing, which is particularly useful in emerging adulthood (Berger, 2018a). The second category embodies flexibility and innovation, while the third one outlines the skills for solving everyday problems (Berger, 2018b). The issue of intelligence is complex, and there is no common way to measure it.
Information processing abilities tend to change, particularly in late adulthood. In the first step, input, sensory memory sometimes cannot detect external stimuli, and the brain automatically compensates for the loss (Berger, 2018d). The second step, memory, is threatened by a certain stereotype: the fear of losing it leads to its damage (Berger, 2018d). Source amnesia frequently occurs in late adulthood, and the prospective and working memory also fade, affecting one’s ability to multitask (Berger, 2018a). The third phase involves control processes, such as memory and retrieval strategies, selective attention, and problem-solving capabilities, which still deteriorate with time (Berger, 2018d). The elderly rely on experiences and emotions, and it is the key to managing their control processes: for instance, familiar music can help people with dementia remember their special moments (Awet Wedi Teklu, 2020). The final stage, output, is not accurately measured by cognitive tests but reflected in daily most realistic circumstances, according to the principle of ecological validity (Berger, 2018a). The abovementioned phases should be studied further to improve the well-being of individuals in late adulthood.
Awet Wedi Teklu. (2020). Prima ballerina Marta.C. Gonzalez Valencia listens to Swan Lake, and it all comes back to her. YouTube. Web.
Berger, K. S. (2018a). Invitation to the life span (4th ed.). Worth Publishers.
Berger, K. S. (2018b). Adulthood: Body and mind [PowerPoint slides]. Worth Publishers.
Berger, K. S. (2018c). Adulthood: Emerging adulthood [PowerPoint slides]. Worth Publishers.
Berger, K. S. (2018d). Late adulthood: Body and mind [PowerPoint slides]. Worth Publishers.
Professor Ross. (2017). Brain games – Fluid and crystallized intelligence as we age. YouTube.
SciShow. (2012). Why we age – And how we can stop it. YouTube. Web.