24.2 Information Processing After Age 65

Given the complexity, variation, and diversity of late-life cognition, we need to examine specifics to combat general stereotypes. For this purpose, the information-processing approach is useful, with details of input (sensing), memory (storage), control processes (programming), and output.

Input

The first step in information processing is input, in which the brain receives information from the senses, but, as Chapters 20 and 23 explain, no sense is as sharp at age 65 as at age 15. Glasses and hearing aids mitigate severe sensory losses, but more subtle deficits impair cognition as well. In order to be perceived, information must cross the sensory threshold—the divide between what is sensed and what is not. [Lifespan Link: Sensory memory is explained in Chapter 12.]

A person may not recognize sensory losses because the brain automatically fills in missed sights and sounds. People of all ages believe they look at the eyes of their conversation partner, yet a study that examined the ability to follow a gaze found that older adults were less adept at knowing where someone was looking (Slessor et al., 2008). That creates a disadvantage in social interactions. Another study found that already by age 50, adults were less adept at reading emotions by looking at the eyes (Pardini & Nichelli, 2009).

Acute hearing is another way to detect emotional nuances. Older adults are less able to decipher the emotional content in speech, even when they hear the words correctly (Dupuis & Pichora-Fuller, 2010). Particularly for them, understanding speech is impaired when vision is impaired (Tye-Murray et al., 2011), probably because watching lips and facial expressions aids understanding. Thus, small sensory losses—not noticed by the person or family but inevitable with age—impair cognition.

I know a father—not elderly but already with fading eyesight—who was scolding his 6-year-old daughter. Without his glasses, he could not see that her lip had started to quiver. He was surprised when she cried; he did not realize how harsh his words seemed to her.

The cognition of almost 2,000 intellectually normal older adults, average age 77, was repeatedly tested 5, 8, 10, and 11 years after the initial intake (Lin et al., 2013). At the 5-year retesting, an audiologist assessed their hearing. Between the start of the study and 11 years later, the average cognitive scores of the adults with hearing loss (who were often unaware of it) were down 7 percent, while those with normal hearing lost 5 percent.

That 2 percent difference seems small, but statistically it was highly significant (.004). Furthermore, greater hearing losses correlated with greater cognitive declines (Lin et al., 2013). Many other researchers likewise find that small input losses have a notable effect on output.

Memory

After input, the second step is processing whatever input has come from the senses. Stereotype threat impedes this processing. [Lifespan Link: Stereotype threat was discussed in Chapter 18.] If older people suspect memory loss, anxiety itself impairs their memory (Ossher et al., 2013). Worse than that, simply knowing that they are taking a memory test makes them feel years older (Hughes et al., 2013). As you learned in Chapter 23, feeling old itself impairs health.

The more psychologists study memory, the more they realize that memory is not one function but many, each with a specific pattern of loss. Some losses of the elderly are quite normal and others pathological (Markowitsch & Staniloiu, 2012). The inability to recall a word or a name is a normal loss of one aspect of memory, and does not indicate that memory, overall, is fading.

Generally, explicit memory (recall of learned material) shows more loss than implicit memory (recognition and habits). That means that names are harder to remember than actions. Grandpa can still swim, ride a bike, and drive a car, even if he cannot name both U.S. senators from his state.

One memory deficit is source amnesia—forgetting the origin of a fact, idea, or snippet of conversation. Source amnesia is particularly problematic in the twenty-first century, as video, audio, and print information bombard the mind.

In practical terms, source amnesia means that elders might believe a rumor or political advertisement because they forget the source. Compensation requires deliberate attention to the reason behind a message before accepting a con artist’s promises or the politics of a TV ad. However, elders are less likely than younger adults to analyze, or even notice, information surrounding the material they remember (Boywitt et al., 2012).

Another crucial type of memory is called prospective memory—remembering to do something in the future (to take a pill, to meet someone for lunch, to buy milk). Prospective memory also fades notably with age (Kliegel et al., 2008). This loss becomes dangerous if, for instance, a person cooking dinner forgets to turn off the stove, or if someone is driving on the thruway in the far lane when the exit appears.

The crucial aspect of prospective memory seems to be the ability to shift the mind quickly from one task to another: Older adults get immersed in one thought and have trouble changing gears (Schnitzspahn et al., 2013). For that reason, many elders follow routine sequences (brush teeth, take medicine, get the paper) and set an alarm to remind them to leave for a doctor’s appointment. That is compensation.

Working memory (remembering information for a moment before evaluating, calculating, and inferring its significance) also declines with age. Speed is critical: Some older individuals take longer to perceive and process sensations, which reduces working memory because some items fade before they can be considered (Stawski et al., 2013).

For example, a common test of working memory is to have someone repeat backwards a string of digits just heard, but if the digits are said quickly, a slow-thinking person may be unable to process each number and then hold them all in memory. Speed of processing would explain why memory for vocabulary (especially recognition memory, not recall) is often unaffected by age. For instance, speed is irrelevant in knowing that chartreuse is a color, not an animal.

Some research finds that when older people have adequate time, working memory does not fade. Speed is crucial when comparing working memory between one older adult and another, but paying attention becomes the critical factor when a person is tested repeatedly over several days (Stawski et al., 2013).

Thus adequate time and careful attention are both crucial. This explains interesting results from a study of reading ability. In that research, older people reread phrases more often than younger people did, but when both groups had ample time to pay attention, comprehension was not impaired by age (Stine-Morrow et al., 2010).

Control Processes

The next step in information processing involves control processes (discussed in Chapter 12). Many scholars believe that the underlying impairment of cognition in late adulthood is in this step, as information from all parts of the brain is analyzed by the prefrontal cortex. Control processes include selective attention, strategic judgment, and then appropriate action—the so-called executive function of the brain.

Instead of using analysis and forethought, the elderly tend to rely on prior knowledge, general principles, familiarity, and rules of thumb as they make decisions (Peters et al., 2011), basing actions on past experiences and current emotions.

For example, casinos have noticed that elderly gamblers gravitate to slot machines rather than to games where analysis is helpful. The reason, according to a study of brain scans of young and old slot players, is that the activated parts of older brains are less often the regions in which analysis occurs (McCarrey et al., 2012). When gamblers are able to analyze the odds, as younger players do, they spend less time with slots.

One particular control process is development of strategies for retrieval. Some developmentalists believe that impaired retrieval is an underlying cause of intellectual lapses in old age because elders have many thoughts and memories that they cannot access. Since deep thinking requires recognizing and comparing the similarities and differences in various experiences, if a person cannot retrieve memories of the past, new thinking is more shallow than it might otherwise be.

Inadequate control processes may explain why many older adults have extensive vocabularies (measured by written tests) but limited fluency (when they write or talk), why they are much better at recognition than recall, why tip-of-the-tongue forgetfulness is common, and why spelling is poorer than pronunciation.

Many gerontologists think elders would benefit by learning better control strategies. Unfortunately, even though “a high sense of control is associated with being happy, healthy, and wise,” many older adults resist suggested strategies because they believe that declines are “inevitable or irreversible” and that no strategy can help (Lachman et al., 2009, p. 144). Efforts to improve their use of control strategies are often discouraging (McDaniel & Bugg, 2012).

Output

The final step in information processing is output. In daily life, output is usually verbal. If the timbre and speed of a person’s speech sounds old, ageism might cause listeners to dismiss the content without realizing that the substance may be profound. Then, if elders realize that what they say is ignored, they talk less. Output is diminished. This provides guidance for anyone who wants to respect and learn from someone else: We all talk more if we think someone is listening appreciatively.

Scientists usually measure output through use of standardized tests of mental ability. As already noted, if older adults think their memory is being tested, that alone impairs them (Hughes et al., 2013). Even without stereotype threat, output on cognitive tests may not reflect ability, as you will now see.

In the Seattle Longitudinal Study (described in Chapter 21), the measured output of all five primary mental abilities—verbal meaning, spatial orientation, inductive reasoning, number ability, and word fluency—declined, beginning at about age 60. This decline was particularly notable in spatial perception and processing speed (Schaie, 2013).

Similar results are found in many tests of cognition: Thus, the usual path of cognition in late adulthood as measured by psychological tests is gradual decline, at least in output (Salthouse, 2010). However, such tests are normed and validated via the output of younger adults. To avoid cultural bias, many questions are quite abstract and timed, since speed of thinking correlates with intelligence for younger adults. A smart person is said to be a “quick” thinker, the opposite of someone who is “slow.”

But abstract thinking and processing speed are the aspects of cognition that fade most with age. Is there a better way to measure output in late adulthood?

Perhaps ability should be measured in everyday tasks and circumstances, not as laboratory tests assess it. To do measurements in everyday settings is to seek ecological validity, which may be particularly important when measuring cognition in the elderly (Marsiske & Margrett, 2006).

For example, because of changes in their circadian rhythm, older adults are at their best in the early morning, when adolescents are half asleep. If a study were to compare 85-year-olds and 15-year-olds, both tested either at 8 A.M. or at 4 P.M., comparisons would reflect time of day, not just mental ability. Ecological validity might require different testing times for each age group.

Similarly, if intellectual ability were to be assessed via a timed test, then faster thinkers (usually young) would score higher than slower thinkers (usually old), even if the slower ones would be more accurate with a few more seconds to think. Furthermore, contextual effects might cause anxiety, for instance, if the test occurred in a college laboratory.

Indeed, age differences in prospective memory are readily apparent in laboratory tests but disappear in some naturalistic settings, a phenomenon called the “prospective memory-paradox” (Schnitzspahn et al., 2011). Motivation seems crucial; elders are less likely to forget whatever they believe is important—phoning a child on their birthday, for instance.

Similarly, as already noted, older adults are not as accurate as younger adults when tested on the ability to read emotions by looking at someone’s face or listening to someone’s voice. But seeing and hearing are less acute with age, so they may not be the best way to measure empathy in older adults. Accordingly, a team decided to measure empathy when visual contact was impossible.

Their study included a hundred couples who had been together for years, and each of the participants was repeatedly asked to indicate their own emotions (how happy, enthusiastic, balanced, content, angry, downcast, disappointed, nervous they were) and to guess the emotions of their partner at that moment. Technology helped with this: The participants were beeped at various times, and indicated their answers on a smart phone they kept with them. Sometimes they happened to be with their partner, sometimes not.

When the partner was present, accuracy was higher for the younger couples, presumably because they could see and hear their mate. But when the partner was absent, the older participants were as good as the younger ones (see Figure 24.3). Could you

The fundamental ecological issue for developmentalists is what should be assessed—pure, abstract thinking or practical, contextual thought, depersonalized abilities, or everyday actions? Traditional tests of cognition emphasize fluid abilities, but problem solving and emotional sensitivity may be more crucial. Those practical abilities are not measured by traditional cognitive tests.

Awareness of the need for ecological validity has helped scientists restructure research on memory. Restructured studies find fewer deficits than originally thought. However, any test may overestimate or underestimate ability. For instance, what is an accurate test of long-term memory? Many older people recount, in vivid detail, events that occurred decades ago. That is impressive … if the memories are accurate.

Unfortunately, “there is no objective way to evaluate the degree of ecological validity … because ecological validity is a subjective concept” (Salthouse, 2010, p. 77). It is impossible to be totally objective in assessing memory; memory is always subjective.

We know that stereotypes are insidious, that global assessments are over-simplified, that emotions affect output. We know that individuals vary, and that some but not all kinds of memory show notable age-related loss.

The final ecological question is, “What is memory for? “Older adults usually think they remember well enough. Fear of memory loss is more typical at age 60 than at age 80. Unless they develop a brain condition such as Alzheimer disease (soon described), elders are correct: They remember how to live their daily lives. Is that enough?