By Jesse Schneider

People 65 and older now outnumber children under 5. With this demographic shift, the ways in which we understand the aging population has also changed.

In a presentation to National Press Foundation fellows, Darlene Howard, a professor emerita in Georgetown University’s Department of Psychology, differentiated between the “old view” and “new view” of aging and outlined four areas in which old norms on aging and have been replaced by a more current understanding.

For starters, older research that indicated all cognitive ability declines with age isn’t entirely true. In fact, cognitive decline is selective. Howard pointed to memory as an illustration of this phenomenon. Older people may struggle with word retrieval – that feeling of having a word on “the tip of my tongue” but they are much less likely to forget word definitions or universally-known facts.

Rather than deteriorating with age, as the old view held, the aging brain simply functions differently. An example: When young people do a working memory test, one side of their brain is activated; the process is known as unilateral recruitment. In contrast, when older people perform this same test, bilateral recruitment occurs, meaning both hemispheres of the brain are activated.

Researchers once believed that age-related decline was impossible to slow down. But recent studies have shown the opposite. Socialization, lifelong bilingualism and exercise all slow aging and the decline of neurons in the brain. Howard said there is strong evidence on the impact of exercise.

“Beyond any doubt, physical exercise matters,” she said.

Finally, Howard noted that, contrary to previous beliefs, people can do a lot to delay symptoms of Alzheimer’s disease. The bad news: A drug that can effectively do this does not yet exist. The good news: Lifestyle choices may at least delay the symptoms of Alzheimer’s and instances of dementia have been steadily declining.