Psychology of Aging: Personality, Cognition, and Technology

Stage and Trait Theories of Adult Personality Development

Child developmentalists traditionally categorized adult personality development into stage theories (Kagan, 2001). Sigmund Freud advocated the psychosexual stage theory, which held that personality is shaped early in life and generally resists change. Carl Jung proposed the opposite — that personality continues to develop in adulthood. Other theories emerged in the 1930s and 1940s in Europe and the United States, such as Charlotte Bühler's framework, which called for empirical evaluations of theoretical predictions, and Erik Erikson's psychoanalytic stage theory, which asserts that a person develops through stages defined by fundamental human needs. Eventually, these early stage theories failed empirical tests. Critics argued that personality does not evolve systematically in adulthood. The Trait Theory then emerged in the 1980s, suggesting that personality changes only slightly once a person reaches age 30 (Kagan, 2001).

The Trait Theory proposes that there is very little change in personality from adulthood through old age (Kagan, 2001). Its critics hold that it is unable to predict behavior or adjust focus to particular strategies. Life-span theories subsequently developed from social cognitive theory. They suggest that individuals shape their own environments and that the process of personality development moves toward adaptation. Two key principles guide this framework. The first states that time and space influence adaptation, which occurs more in infancy and early childhood than in later years. The second involves specialized adaptation within a given environment, which sustains an individual's self-views. As a person ages, he tends to reduce his social circles and form stable social structures that persist throughout life. The framework also maintains that adaptation is never complete, in that flexibility to certain circumstances may not be as strong as flexibility to others (Kagan, 2001).

Life-span development is motivational in that an individual is driven by the basic human needs for competence, relatedness, and autonomy throughout his entire lifetime (Kagan, 2001). A second perspective on personality focuses on emotions during challenging times and how those emotions are regulated. A third perspective holds that, as a person ages and encounters more challenges, his outlook and values undergo change (Kagan, 2001).

Comparing these alternative theories and findings on adult personality development suggests that continuity and personality change together best characterize adulthood. People have been observed to remain broadly consistent across adulthood, yet goals tend to shift as a person ages, emotions become better regulated, and new qualities emerge with advancing years (Kagan, 2001).

Several sensory modalities are affected by aging, including tactile sensitivity, vibration perception at 40 and 250 Hz, the ability to detect increases and decreases in temperature, and sensitivity to noxious heat (Wickremaratch & Llewelyn, 2006). Tactile thresholds in older people are substantially higher than in younger people. This may be attributed to reduced density and distribution of Pacinian and Meissner's corpuscles and Merkel's discs in the skin, resulting in reduced spatial sharpness. Thermal and transcutaneous electrical nerve stimulation pain thresholds are also elevated in older individuals. Age-related changes in the perception of pain and temperature appear largely due to slower-conducting C fibers.

Factors Contributing to Accelerated Sensory Decline

The sense of vibration is also diminished in older adults relative to younger persons, as demonstrated by 12 performance-based tests measuring muscle strength, balance, gait, somatosensory discrimination, and reaction time — all of which declined with age. The sense of vibration reaches its peak decline around age 65. Tests of tactile acuity showed that sensitivity diminishes progressively with age, with an average loss of approximately 80% in the foot and fingers among persons aged 65 or older. Additional studies suggested that skin changes contribute significantly to the alteration in touch sensation in older persons. Studies also found that the threshold for perception of electrical stimuli is higher in older volunteers compared with younger ones (Wickremaratch & Llewelyn, 2006).

Two principal cognitive domains are affected by aging: attention and working memory (Gilsky, 2007). Deterioration of attention in aging individuals imposes wide-ranging and long-term effects on their effective daily functioning. The types of attention that have been investigated include selective attention, divided attention, attention switching, and sustained attention. Research findings are not unanimous, but older people generally appear to be slower at managing targets than younger people, while distractions affect both groups similarly. The observed differences may be due more to reduced information processing speed in older adults than to selective attention deficits per se.

Studies have shown that older adults experience greater difficulty when their attention must be divided while performing demanding tasks, compared with young adults. This difficulty is explained by diminishing processing resources in normal aging. The reduction is even more pronounced when attention must be split among two or more objects simultaneously. Performance is likewise diminished when attention must shift from one task to another. Despite this, older adults are generally able to manage vigilance tasks through sustained attention, which requires prolonged concentration (Gilsky, 2007).

Cognitive Functioning and Creative Performance in Aging

Older adults exhibit only slight or no reduction in basic short-term memory — they can typically hold seven digits in mind as long as those digits have been rehearsed (Gilsky, 2007). However, the ability to repeat digits in reverse order deteriorates with age, as this requires active restructuring and control of information held in short-term memory. While it is commonly believed that working memory is impaired in older adults, experts do not agree on the underlying mechanisms, and further research is needed (Gilsky, 2007).

Healthcare professionals, teachers, supervisors, and researchers must always consider the effects of cultural background, age, and other individual differences when working with clients and their families (ASHA, 2015). Regardless of a client's personal culture, age, setting, or demographics, these professionals should strive to deliver culturally and individually appropriate services. This approach affects all aspects of professional practice, including assessment procedures, diagnostic criteria, treatment plans, discharge decisions, and research design. Providers should endeavor to understand, protect, and respect the client, and to enter into a close professional relationship with sensitive awareness of the client's specific status, characteristics, strengths, limitations, and preferences. Providers must take proper care to avoid misdiagnosis and inappropriate treatment, particularly for the aging client (ASHA, 2015).

Nurses are guided by five provisions set forth in the ANA Code of Ethics addressing cultural barriers, education, end-of-life wishes, and lifestyle choices in their dealings with elderly patients (Ludwick & Cipriano Silva, 2015).