MEMORY AND AGE

A. Aging, it is now clear, is part of an ongoing maturation process that all our organs go through. “In a sense, aging is keyed to the level of the vigor of the body and the continuous interaction between levels of body activity and levels of mental activity,” reports Arnold B. Scheibel, M.D., whose very academic title reflects how once far-flung domains now converge on the mind and the brain. Scheibel is a professor of anatomy, cell biology, psychiatry, and behavioral sciences at the University of California at Los Angeles, and director of university’s Brain Research Institute. Experimental evidence has backed up popular assumptions that the aging mind undergoes decay analogous to that of the aging body. Younger monkeys, chimps, and lower animals consistently outperform their older colleagues on memory tests. In humans, psychologists concluded, memory and other mental functions deteriorate over time because of inevitable organic changes in the brain as neurons die off. The mental decline after young adulthood appeared inevitable.
B. Equipped with imaging techniques that capture the brain in action, Stanley Rapoport, Ph.D., at the National Institutes of Health, measured the flow of blood in the brains of old and young people as they went through the task of matching photos of faces. Since blood flow reflects neuronal activity, Rapoport could compare with networks of neurons were being used by different subjects. “Even when the reaction times of older and younger subjects were the same, the neural networks they used were significantly different. The older subjects were using different internal strategies to accomplish the same result in the same time,” Rapoport says. Either the task required greater effort on the part of the older subjects or the work of neurons originally involved in tasks of that type had been taken over by other neurons, creating different networks.
C. At the Georgia Institute of Technology, psychologist Timothy Salthouse, Ph.D., compared a group of very fast and accurate typists of college-age with another group in their 60s. since reaction time is faster in younger people and most people’s fingers grow less nimble with age, younger typists might be expected to tap right along while the older one's fumble. But both typed 60 words a minute. The older typists, it turned out, achieved their speed with cunning little strategies that made them far more efficient than their younger counterparts: They made fewer finger movements, saving a fraction of a second here and there. They also read ahead in the text. The neural networks involved in typing appear to have been reshaped to compensate for losses in motor skills or other age changes.
D. “When a rat is kept in isolation without playmates or objects to interact with, the animal’s brain shrinks, but if we put that rat with 11 other rats in a large cage and give them an assortment of wheels, ladders, and other toys, we can show—after four days—significant differences in its brain,” says Diamond, professor of integrative biology. Proliferating dendrites first appear in the visual association areas. After a month in the enriched environment, the whole cerebral cortex has expanded, a has its blood supply. Even in the enriched environment, rats get bored unless the toys are varied. “Animals are just like we are. They need stimulation,” says Diamond.
One of the most profoundly important mental functions is memory-notorious for its failure with age. So important is a memory that the Charles A. Dana foundation recently spent $8.4 million to set up a consortium of leading medical centers to measure memory loss and aging through brain-imaging technology, neurochemical experiment, and cognitive and psychological tests. One thing, however, is already fairly clear—many aspects of memory are not a function of age at all but of education. Memory exists in more than one form. What we call knowledge—facts—is what psychologists such as Harry P. Bahrick, Ph.D., of Ohio Wesleyan University call semantic memory. Events, conversations, and occurrences in time and space, on the other hand, make up episodic or event memory, which is triggered by cues from the context. If you were around in 1963 you don’t need to be reminded of the circumstances surrounding the moment you heard that JFK had been assassinated. That event is etched into your episodic memory.
E. When you forget a less vivid item, like buying a roll of paper towels at the supermarket, you may blame it on your aging memory. It’s true that episodic memory begins to decline when most people are in their 50s, but it’s never perfect at any age. “Every memory begins as an event,” says Bahrick. “Through repetition, certain events leave behind a residue of knowledge or semantic memory. On a specific day in the past, somebody taught you that two and two are four, but you’ve been over that information so often you don’t remember where you learned it. What started as an episodic memory has become a permanent part of your knowledge base.” You remember the content, not the context. Our language knowledge, our knowledge of the world and of people, is largely that permanent or semi-permanent residue.
F. Probing the longevity of knowledge, Bahrick tested 1,000 high school graduates to see how well they recalled their algebra. Some had completed the course as recently as a month before, others as long as 50 years earlier. He also determined how long each person had studied algebra, the grade received, and how much the skill was used over the course of adulthood. Surprisingly, a person’s grasp of algebra at the time of testing did not depend on how long ago he’d taken the course—the determining factor was the duration of instruction. Those who had spent only a few months learning algebra forgot most of it within two or three years.
G. In another study, Bahrick discovered that people who had taken several courses in Spanish, spread out over a couple of years, could recall, decades later, 60 per cent or more of the vocabulary they learned. Those who took just one course retained only a trace after three years. “This long-term residue of knowledge remains stable over the decades, independent of the age of the person and the age of the memory. No serious deficit appears until people get to their 50s and 60s, probably due to the degenerative processes of aging rather than a cognitive loss.”
H. “You could say metamemory is a byproduct of going to school,” says psychologist Robert Kail, Ph.D., of Purdue University, who studies children from birth to 20 years, the time of life when mental development is most rapid. “The question-and-answer process, especially exam-taking, helps children learn—and also teaches them how their memory works. This may be one reason why, according to a broad range of studies in people over 60, the better educated a person is, the more likely they are to perform better in life and on psychological tests. A group of adult novice chess players were compared with a group of child experts at the game. In tests of their ability to remember a random series of numbers, the adults, as expected, outscored the children. But when asked to remember the patterns of chess pieces arranged on a board, the children won. “Because they’d played a lot of chess, their knowledge of chess was better organized than that of the adults, and their existing knowledge of chess served as a framework for new memory,” explains Kail.
I. Specialized knowledge is a mental resource that only improve with time. Crystallized intelligence about one’s occupation apparently does not decline at all until at least age 75, and if there is no disease or dementia, may remain even longer. Special knowledge is often organized by a process called “chunking.” If procedure A and procedure B are always done together, for example, the mind may merge them into a single command. When you apply yourself to a specific interest—say, cooking—you build increasingly elaborate knowledge structures that let you do more and do it better. This ability, which is tied to experience, is the essence of expertise. Vocabulary is one such specialized form of accrued knowledge. Research clearly shows that vocabulary improves with time. Retired professionals, especially teachers and journalists, consistently score higher on tests of vocabulary and general information than college students, who are supposed to be in their mental prime.

FACIAL EXPRESSION 1

A. A facial expression is one or more motions or positions of the muscles in the skin. These movements convey the emotional state of the individual to observers. Facial expressions are a form of nonverbal communication. They are a primary means of conveying social information among aliens, but also occur in most other mammals and some other animal species. Facial expressions and their significance in the perceiver can, to some extent, vary between cultures with evidence from descriptions in the works of Charles Darwin. 

B. Humans can adopt a facial expression to read as a voluntary action. However, because expressions are closely tied to emotion, they are more often involuntary. It can be nearly impossible to avoid expressions for certain emotions, even when it would be strongly desirable to do so; a person who is trying to avoid insulting an individual he or she finds highly unattractive might, nevertheless, show a brief expression of disgust before being able to reassume a neutral expression. Microexpressions are one example of this phenomenon. The close link between emotion and expression can also work in the order direction; it has been observed that voluntarily assuming an expression can actually cause the associated emotion. 

C. Some expressions can be accurately interpreted even between members of different species – anger and extreme contentment being the primary examples. Others, however, are difficult to interpret even in familiar individuals. For instance, disgust and fear can be tough to tell apart. Because faces have only a limited range of movement, expressions rely upon fairly minuscule differences in the proportion and relative position of facial features, and reading them requires considerable sensitivity to the same. Some faces are often falsely read as expressing some emotion, even when they are neutral because their proportions naturally resemble those another face would temporarily assume when emoting. 

D. Also, a person’s eyes reveal much about hos they are feeling, or what they are thinking. Blink rate can reveal how nervous or at ease a person maybe. Research by Boston College professor Joe Tecce suggests that stress levels are revealed by blink rates. He supports his data with statistics on the relation between the blink rates of presidential candidates and their success in their races. Tecce claims that the faster blinker in the presidential debates has lost every election since 1980. Though Tecce’s data is interesting, it is important to recognize that non-verbal communication is multi-channelled, and focusing on only one aspect is reckless. Nervousness can also be measured by examining each candidates’ perspiration, eye contact and stiffness. 

E. As Charles Darwin noted in his book The Expression of the Emotions in Man and Animals: the young and the old of widely different races, both with man and animals, express the same state of mind by the same movements. Still, up to the mid-20th century, most anthropologists believed that facial expressions were entirely learned and could, therefore, differ among cultures. Studies conducted in the 1960s by Paul Ekman eventually supported Darwin’s belief to a large degree. 

F. Ekman’s work on facial expressions had its starting point in the work of psychologist Silvan Tomkins. Ekman showed that contrary to the belief of some anthropologists including Margaret Mead, facial expressions of emotion are not culturally determined, but universal across human cultures. The South Fore people of New Guinea were chosen as subjects for one such survey. The study consisted of 189 adults and 130 children from among a very isolated population, as well as twenty-three members of the culture who lived a less isolated lifestyle as a control group. Participants were told a story that described one particular emotion; they were then shown three pictures (two for children) of facial expressions and asked to match the picture which expressed the story’s emotion. 

G. While the isolated South Fore people could identify emotions with the same accuracy as the non-isolated control group, problems associated with the study include the fact that both fear and surprise were constantly misidentified. The study concluded that certain facial expressions correspond to particular emotions and can not be covered, regardless of cultural background, and regardless of whether or not the culture has been isolated or exposed to the mainstream. 

H. Expressions Ekman found to be universally included those indicating anger, disgust, fear, joy, sadness, and surprise (not that none of these emotions has a definitive social component, such as shame, pride, or schadenfreude). Findings on contempt (which is social) are less clear, though there is at least some preliminary evidence that this emotion and its expression are universally recognized. This may suggest that the facial expressions are largely related to the mind and each part on the face can express specific emotion.