Think Positively

T h Positively i n k

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Photo by Marcelo Mokrejs

T

he image of the “grumpy old man” may be more myth than reality. Recent research by Dr. Laura Carstensen, a Stanford professor in the Department of Psychology and director of the Life-span Development Laboratory, suggests that emotional experience and satisfaction actually improve with age. Carstensen’s group has found that old people are happier, more pleased with their relationships, less depressed and better able to manage their emotional lives than younger people. Data from Carstensen’s studies indicate a developmental pattern in which a preference for negative material in youth shifts to a disproportionate preference for positive material in later life – what she refers to as the “positivity effect”. This effect can be seen as an increase in the ratio of positive

Older adults are less likely to retain negative information than their younger counterparts. to negative material remembered as an individual ages. Carstensen argues that this effect is driven by increased memory for and attention to negative information in youth, as well as increased memory for and attention to positive information in old age. Her theory posits that this shift is due to changing motivational goals throughout life, rather than any type of cognitive decline. This line of research prompts the development of methods for improving the lives of both older and younger adults.

Aging and the “Positivity Effect” Psychology professors Susan Charles and Mara Mather at the University of California, Irvine and University

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A look at how and why aging may benefit emotional By Rachel Nass experience

of California, Santa Cruz, respectively, teamed up with Carstensen to conduct a study in 2003 that had young, middle-aged and older adults watch a slide show consisting of negative, neutral and positive pictures. Following the slide show, the adults were asked to recall as many pictures as possible. The researchers found that while younger adults remember more pictures overall, the ratio of negative to positive images remembered decreases with age. In other words, a bias for remembering negative pictures in youth disappears in old age, meaning that older adults are less likely to retain negative information than their younger counterparts. These effects were observed in men and women, African- and European-Americans, and people of high and low socioeconomic status. The “positivity effect” also reveals itself outside of the laboratory setting. Carstensen has found that older adults are more likely than younger adults to recall their past experiences optimistically. Older adults are also more likely to emphasize the positive features of their choices and are more satisfied with their decisions than are younger adults. For instance, when asked to choose between two different models of cars, older adults spend a larger proportion of their time reviewing positive features of the cars, whereas younger adults are likely to focus equally on both positive and negative features.

Explaining the Preference for the Positive: The Role of Motivation and Emotion Regulation Because physical and cognitive decline is inevitable, the idea that subjective well-being can be enhanced in old age is hard to fathom. Carstensen refers to this apparent contradiction as the “paradox of aging”. To explain this counter intuitive finding, the “positivity effect” may be another result of declining cognitive ability.

Because positive information could be simpler and easier to process than negative information, one theory suggests that the effect is just an unintentional byproduct of general decline. Carstensen rejects such an explanation. According to her, “with age, people stop worrying so much about things such as status and power, and that’s what makes them happy. They can see clearly what’s really important.” Specifically, Carstensen argues that whereas younger people view time as open-ended, older people see it as more constrained. The result is that a desire for power and status in youth yields

‘It’s not just an age-related message.’ to a motivation to pursue emotional satisfaction in old age. Thus, older adults are more likely to allocate attention, memory and other cognitive resources towards acquiring information that will improve their moods. Carstensen’s explanation is supported by experimental evidence that one can make younger people think like older people and vice versa by artificially altering their time horizons. When time is viewed as open-ended (usually by youths), goals are most likely to be preparatory - for example, gathering information, experiences, and knowledge. When constraints on time are perceived (usually when one is older), goals focus more on objectives that can be realized - such as those emphasizing feelings, and especially those regulating emotional states to optimize well-being. For example, when emotional goals are made obvious to young adults by asking them how they feel about the choices they have made, young adults respond more positively and in a way that resembles the “positivity bias” observed in the older adults.

The “Positivity Effect” and the Brain Neuroanatomical imaging studies also support Carstensen’s findings. These studies investigate activation within the amygdala, a key center for emotion processing in the brain, and suggest that the amygdala responds differently to positive and negative information with age. Both older Perceptions of Images Recalled over Time Positive Negative

Neutral

Young

Middle

Old

Charles, S. T., Mather, M., & Carstensen, L. L. (2003). Aging and emotional memory: The forgettable nature of negative images for older adults. Journal of Experimental Psychology: General, 132, 313.

This graph illustrates the average number of positive, negative, and neutral images recalled by young, middle, and old adults in the 2003 study by Charles, Mather, and Carstensen. Results indicate that the ratio of negative to positive images remembered decreases with age.

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and younger adults show similar amygdala activation when viewing positive pictures, but older adults show less activation compared to their younger peers when viewing negative images. This result supports the view that older adults use cognitive resources to diminish their responses to negative information. In fact, studies show that when viewing faces with negative expressions, older adults simultaneously display diminished activation in the amygdala and increased activation in the anterior “Grumpy” older people may be just a myth cingulate, medial prefrontal cortex and orbital/ventromedial frontal cortex. Whereas the amygdala’s response to emotional information is involuntary, these latter areas of the brain are subject to cognitive control, meaning that a response is influenced by an individual’s goals and choices to attend to or ignore such information. Thus, increased activation in these latter areas, coupled with decreased activation in the amygdala, suggests that older adults actively reduce their response to negative information.

Implications and Directions for the Future: Improving Well-Being in Old Age and Across the Life Span Carstensen hopes that her findings will be used to improve the lives of older adults. If older people remember positive information better than negative information, it would be wise to restructure health messages in a more positive light, for example. Subtle changes such as emphasizing the benefits of exercise and healthy diet rather than the consequences of failure to engage in these activities could be powerful. Carstensen also points out that her research is broadly applicable because it highlights the ways in which aging “can inform general knowledge about human nature.” Her theory suggests that older people are happier primarily because they are less concerned with status and power, and more concerned with deepening existing relationships and savoring life. This finding could have important implications for improving happiness among people of all ages. “It’s not just an age-related message,” says Carstensen. With this in mind, it may be wise to rethink our stereotypes and assumptions about the elderly, as well as the notion that aging is simply a trend of overall decline. Instead of fearing the inevitable, we may look forward to getting old. S Rachel Nass is a senior majoring in Psychology, and will be attending law school next year. In her free time, she enjoys tennis, golf, running, and the beach. To Learn More: Laura Carstensen’s Life-Span Development http://www-psych.stanford.edu/%7Elifespan/

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