Could something other than aging or dementia be to blame for my fuzzy thinking?

DEAR DOCTOR K: Lately my mind and memory have not been as sharp as usual. Could something other than aging or dementia be to blame?

DEAR READER: I'm glad you asked, because memory or thinking problems often lead people to worry that they are developing dementia. Most causes of dementia don't yet have cures. However, there are several underlying conditions that often affect memory and thinking -- conditions that can be cured. And they are often overlooked.

What is astigmatism?

DEAR DOCTOR K: At my last visit, my eye doctor told me I have astigmatism. He told me what that means, but I still don't really understand what it is. Please explain it to me.

DEAR READER: Astigmatism means that the eye's cornea has an irregular shape, which causes vision problems. Astigmatism is very common; I am among the several billion people who have it. Fortunately, it's easy to correct.

Is frozen produce less nutritious than fresh?

DEAR DOCTOR K: I'm trying to eat more fruits and vegetables, but I don't have time to go to the grocery store every week. So I stock up on frozen produce. Am I missing out on any nutritional benefits by eating frozen instead of fresh?

DEAR READER: For taste, variety and quality of nutrients, recently picked local produce is the way to go. But if fresh produce is inconvenient or beyond your budget, frozen fruits and vegetables provide plenty of nutrition.

Could antidepressants help improve my thinking skills along with my mood?

DEAR DOCTOR K: I suffer from depression. My doctor told me that depression can cause cognitive impairment. Antidepressants improve my mood -- can they help improve my thinking skills as well?

DEAR READER: Depression is more than long bouts of intense sadness. People who suffer from depression often also experience a loss of energy and interest in things they once enjoyed.

What, besides diabetes, can cause peripheral neuropathy?

DEAR DOCTOR K: I have peripheral neuropathy. I know that people with diabetes often get neuropathy, but I'm not diabetic. What else can cause this condition? And what can I do about it?

DEAR READER: Neuropathy is a medical term that means nerve damage. The type of nerve damage that people with diabetes get involves specific nerve fibers in all nerves, particularly the nerves that travel to the legs and feet. (There are other conditions in which a single nerve leading to the legs and feet is pinched, causing pain. An example is what is often called a "slipped disk" or "herniated disk" in the lower part of the spine.)

Do financial incentives really help people change their health behaviors?

DEAR DOCTOR K: My employer has started offering employees financial rewards for weight loss. I'm skeptical. Does this kind of financial incentive really work?

DEAR READER: Offering financial incentives to employees for making healthy lifestyle changes is increasingly common. These days, nearly 80 percent of large employers do it. There are many ways to offer incentives, and doctors and economists are still learning what works best.

Will reducing stress reduce my risk of heart disease?

DEAR DOCTOR K: I'm under a lot of stress in my life. Of course, I don't like that, but what really worries me is that it will affect my heart. Heart disease runs in my family. If stress can lead to heart disease, does reducing stress reduce heart disease risk?

DEAR READER: We often think of the heart and brain as separate from each other, yet these organs are intimately connected. And when your emotions adversely affect your brain, your heart is affected as well.

Can you tell me about the Epley maneuver that helps relieve vertigo?

DEAR DOCTOR K: I suffer from benign paroxysmal positional vertigo. I've heard that something called the Epley maneuver may help. Could you explain what this is?

DEAR READER: Vertigo is the sensation that either your body or your environment is moving, usually spinning. Vertigo can be a symptom of many different illnesses and disorders. The type of vertigo you have -- benign paroxysmal positional vertigo (BPPV) -- is the most common form. As you've probably experienced, simply changing the position of your head can cause a sudden spinning sensation.

What can a caregiver do to take care of themselves?

DEAR DOCTOR K: I'm the primary caregiver for my ill, elderly father. I'm exhausted and upset all the time. What can I do to lighten my load without costing us much? Neither of us is well off.

DEAR READER: You're not alone. Approximately one in five American adults helps an elderly or disabled family member with the daily tasks of life. This caregiving runs the gamut from grocery shopping, cooking and cleaning house, to helping with baths and personal hygiene or providing hands-on medical care. That's often in addition to caring for other family members and holding down a paid job.

Could dancing have more health benefits than standard exercise?

DEAR DOCTOR K: My gym offers several dance-themed exercise classes like Zumba. The brochure claims that dance may have more health benefits than standard exercise. Is that true?

DEAR READER: We dance to express joy, celebrate life events and as a form of exercise. It turns out that the combination of music and dance may have benefits beyond those of exercise alone.