We’ve all seen it happen: An older friend or family member retires, is diagnosed with a serious illness or loses a spouse. Suddenly, this individual’s world is altered, sometimes seemingly beyond recognition. He has reached a fork in the road; will he get stuck or find a way to regroup and move on?

In a new book, “The End of Old Age,” Dr. Marc Agronin, a geriatric psychiatrist, calls this moment an “age point” — an event that disrupts an older person’s life and challenges the person’s ability to cope while also offering the potential for new growth.

Growth is one of Agronin’s primary preoccupations. As director of mental health services at Miami Jewish Health Systems, he says he frequently sees older adults rise to difficult challenges, demonstrating their adaptability and resourcefulness. Yet the oft-repeated narrative of decline associated with aging — that this stage of life is all about loss and deterioration — doesn’t recognize these positives, he argues.

In a wide-ranging discussion, we talked about aging, resilience and how people can prepare for this stage of life. Our conversation has been edited for length and clarity.

Q: How did you become interested in aging issues?

I grew up in a small town in Wisconsin surrounded by lots of older loved ones. Two sets of grandparents. A set of great-grandparents. Many aunts and uncles. I never looked at aging in a negative way. I look at it in terms of what people gained: wisdom.

Q: A key theme of your new book is that aging brings strengths. What kind of strengths?

As we get older and experience a great variety of things, including adversity and loss, we continue to develop and mature in terms of how we view the world. We tend to be better able to weigh competing points of view and find ways to understand and accept them.

We also tend to be less emotionally reactive as the connections between the brain’s fear center, our amygdala, and our frontal lobe become richer and more developed. We’re better able to reflect upon our experiences. And we tend to use more parts of our brain simultaneously when dealing with problems, so there’s greater synergy.

Put all this together and it adds up to wisdom — a key strength of aging.

Q: What do you mean by wisdom?

We can think of wisdom the same way we think of multiple forms of intelligence. One type is based on expert knowledge — things that we’ve learned to do really well. Another type relates to expert decision-making — being really good at understanding and dealing with problems. For some people, wisdom is all about empathy and caring — connecting with other people. For other people, it’s about creativity or spirituality — a transcendent view of life.

Q: Are these strengths reserved only for people in good health or who have enough money to be comfortable? What about seniors in poor health who are barely squeaking by?

A lot of theories of aging leave this group out. They don’t account for people suffering from dementia, other major losses in life or serious illnesses or disabilities.

Those are the individuals I work with every day. I’ve seen over and over again that we can help these people. Expectations have to be adjusted, obviously, when dementia or serious illness enters the picture. We have to adapt and rethink what our purpose is — what can make life meaningful.

I’ve found that if we try to get these seniors involved in activities, to help and support their families, to make sure they’re on the right medications, to provide empathy and care, we can make their lives better.

Q: You highlight the importance of resilience in your book. What makes resilience possible?