Your brain ages just like the rest of your body, and some cognitive abilities naturally decline, but others actually improve. Here are seven ways your brain changes as you get older:
See also: Eight ways to keep your brain sharp
See also: Five medical issues that can be mistaken for dementia
1. Less good at switching focus – but better at details
Our brains take longer to switch from one focus to another as we age. However, research from Germany shows that our brains compensate by paying closer attention to details.
Scientists say that younger people spread their attention wide, gathering lots of information from different sources, whereas older people focus their attention, looking more at detail. This ability to streamline its functions allows the brain to strengthen its abilities.
"To a certain extent, the brain is able to slow down negative effects of aging by increasing its level of attentiveness," explains lead study author Sabrina Schenk, of Germany's Ruhr-Universität Bochum.
2. Older brains shrink
Our brains shrink as we get older, especially the prefrontal cortex at the front of the frontal lobe and the hippocampus - both areas that are important for learning, memory, and other complex mental activities. Scientists suggest that the hippocampus loses 5% of its nerve cells with each passing decade, up to a total loss of 20% by the time you reach your 80s.
While your brain may be smaller and lighter, it can still create new connections between neurones if given the opportunity. Brain scans have shown activity in several regions during some tasks, which researchers suggest is a way of compensating for decline in another area. Mental abilities are "shared" by various parts of the brain so, as some neurones die, their roles are taken up by others.
3. Verbal intelligence improves
While it's true that some cognitive abilities decline with age, overall memory remains strong for most people throughout their 70s. In fact, studies suggest that the average 70-year-old performs as well on many cognitive tests as do many 20-year-olds. Not only that, but older people in their 60s and 70s score significantly higher in verbal intelligence tests than younger people.
4. Never too old to learn
Scientists used to think that the brain was "fixed" after childhood and would begin to decline in midlife. But new research has shown that the brain is capable of "rewiring" itself even in our later years – and what you choose to do with your brain influences its structure.
Activities that require intense mental focus, such as learning a language, create new neural pathways and strengthen existing ones. Which goes to show that you're never too old to learn.
5. It's harder to get the joke
Previous studies have shown that the 'right' frontal lobe plays a pre-eminent role in our ability to appreciate humour, and that people with right frontal damage (from stroke, tumour or head trauma) have difficulty getting punch lines, and prefer slapstick humour.
Prathiba Shammi, a psychologist with Baycrest Center for Geriatric Care, has carried out a study to show the effects of normal ageing on humour comprehension and appreciation. She found that older people have more trouble comprehending complex humour than their younger counterparts. Why?
Humour comprehension requires abstract reasoning, mental flexibility and working memory - all of which are complex, higher mental functions believed to be associated with the frontal lobes. It's believed that the brain's frontal functions may be the first to deteriorate with ageing.
6. More easily distracted
Do you find it harder to block out distracting noise and images as you get older? Natural changes to your brain could be to blame.
As we get older, our ability to ignore distractions gets worse, according to Karen Campbell, a doctoral student in psychology at the University of Toronto.
However, it's not all bad news. Researchers suggest older people might have the unique ability to "hyper-bind" the irrelevant information, tying it to other information appearing at the same time, which could ultimately improve memory.
7. Slower reasoning skills
Our reasoning skills can slow by 3.6% between our mid-40s to late 50s, according to research published in the British Medical Journal.
The middle-age volunteers displayed poorer memory and verbal fluency on tests. On the bright side, different measures of cognition - such as moral decision-making, regulating emotions and reading social situations - actually improve from middle age onwards.
In addition, the study found that from around the age of 40, people tend to remember positive images more than negative ones - a trend that continues until at least age 80.