Dear Doctor: I never have headaches, but I have visual disturbances that I believe are migraine auras. They're not bothersome and clear up within 10 minutes. But are they dangerous in any way? Am I having a migraine?

Dear Reader: When we venture into the area of migraine, we're entering the unknown. It's one of the leading disorders in the world, and yet when it comes to understanding how or even why migraines occur, we are just beginning to find answers.

The word "migraine" calls up the idea of a monster headache, but the disorder is in fact a collection of symptoms. Sufferers can experience nausea, dizziness, depression, exhaustion, sensory hallucinations, severe neck pain and, as you know firsthand, visual disturbances.

Until recently, migraine was thought to have vascular origins. That is, researchers believed it was the result of the constriction and expansion of blood vessels within and around the brain. With the advent of highly sensitive imaging technologies, however, and thanks to volunteers who have allowed the course of their migraine attacks to be visualized in real time, the focus has now shifted to the brain itself.

At UCLA, we're extremely fortunate to have the Headache Research and Treatment Program, headed by Andrew Charles, M.D., a neurologist and a leading migraine specialist. It's through his research that we now know that fluctuations in brain chemicals, as well as abnormal electrical activity in certain regions of the brain, play a significant role in migraine attacks. This includes not only the extreme headache pain associated with migraine, but the other symptoms as well. In fact, the throbbing, pulsating nature of a migraine headache, once considered to reflect the sufferer's heartbeat, is now believed to sync up with brain waves.

All of which brings us to your question. Visual disturbances that are not accompanied by a headache are known as an ocular migraine. These disturbances can include a circle of flickering zigzag lines that suddenly appear and then slowly expand outward until they leave your field of vision. Some people experience temporary blind spots in their vision, see shimmering patterns or stars, or get random flashes of light.

Scans of migraine patients' brains show waves of abnormal activity that spread across the surface of the brain. There is also stimulation of nerve centers deep within the brain stem. Thanks to the new focus on the brain itself as the source of migraine, researchers are now looking into how ocular migraines tie into altered brain activity.

When it comes to ocular migraine, the symptoms can be temporarily disruptive but are not generally considered serious. In light of the scope of nonheadache symptoms that migraine encompasses, it's a good idea to do a self-check and see whether fatigue, depression, light sensitivity or neck pain either precede or follow your ocular migraine attacks.

Since you're experiencing these symptoms regularly, we suggest a visit with your primary care physician for a definitive diagnosis. Pay attention during the next episode, so you can provide accurate details and a precise timeline of the attack. It will help your physician better understand what is going on and potentially rule out conditions with similar symptoms.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: My husband is in kidney failure, has chronic obstructive pulmonary disease, congestive heart failure and Type 2 diabetes. We have been married 48 years. He sleeps most of the day, is so short of breath that a walk to the bathroom is difficult and never leaves the house except to go to the doctor. He is angry and depressed, often taking his temper out on me. What can I do to help him (and us) besides watch his diet?

Dear Reader: My heart goes out to you and your husband. As you're now painfully aware, and as I've learned as a physician, illness affects not just the person stricken, but their loved ones as well. In your long marriage, you and your husband have undoubtedly had your share of ups and downs, persevering and working together. Now you have new challenges, possibly unimaginable when you were younger, focused on your husband's illnesses.

Let's start with the depression. Some people have the mistaken notion that depression is part of the aging process. In fact, healthy independent elderly adults have a lower rate of depression than the general adult population. But each physical malady increases the risk.

With his many troubles, treating your husband's irritability and depression won't be easy. He may not acknowledge that he is suffering from depression, or he may suggest that, because of his physical ailments, he has every right to be depressed and every right not to go out of the house.

So, if the only time he goes out of the house is to see the doctor, go with him to the doctor. Talk to the doctor about your husband's increasing isolation, his feelings of depression, his irritability -- and his nighttime sleep, which can be affected by his conditions. Notice whether he's having trouble breathing while asleep, snores or awakens frequently to urinate. There may be aspects of his medication that the doctor may want to change to help him sleep more at night and less during the day.

Also, ask your doctor about whether his medications may be causing drowsiness or having depressant effects. These include, but are not limited to, opiates, benzodiazepines (Ativan, Klonopin, Valium, Xanax) and gabapentin, which is often used in diabetic patients for painful neuropathy. Further, pain itself can lead to feelings of depression. So take note of your husband's level of pain and share it with the physician if your husband does not.

Regardless of the root of his depression, psychotherapy could help your husband feel more in control of his situation and help him communicate his needs to you. Similarly, although your husband is likely taking a host of medications and would be hesitant to start another medication, anti-depressants can help decrease his irritability and make him more alert.

With therapy and possibly medication, your husband may be more apt to go outside and do some form of exercise, which will additionally help his mood.

Your love and support for your husband may seem to go unnoticed, but be assured it's a stabilizing foundation for him. That said, improving his mood is ultimately up to him. Your doctor can partner with you both, but your husband has to commit to getting better. Whether he does or doesn't, only time will tell. But, regardless, please take care of yourself. That, too, will benefit you both.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Is kefir really the miracle food that it's cracked up to be? I'll confess that fermented milk does not sound very appealing to me. What is it, exactly? And how much should I consume a day?

Dear Reader: If you've paid attention to food trends over the years, you've seen fads and enthusiasms come and go. This year's super-food becomes next year's shrug of the shoulder. Kale, kombucha, green tea, quinoa, acai berries, oatmeal, salmon and even orange juice have each had their heyday in the headlines.

Now it appears that kefir, a fermented drink traditionally made from the milk of cows, goats or sheep, is having its moment. If you've never tried it, kefir is sometimes mildly effervescent, has a silky texture that is slightly thicker than milk, and has the sharp tang of plain yogurt. It's a good source of protein, calcium and B vitamins, and delivers a generous dose of a range of gut-friendly bacteria. In a time of intense interest in probiotics, it's this last quality that has helped propel kefir into the super-food category.

Kefir comes to us from the Caucasus Mountains, and has long been part of the food traditions of Eastern Europe, Russia and Southwest Asia. It's made by inoculating milk with a substance known as kefir grains. These kefir grains are made up of lactic acid bacteria and beneficial yeasts that are held in a matrix of fats, sugars and proteins. They form irregular clusters that can look a bit like cauliflower florets.

The kefir grains break down the sugars in milk to form lactic acid, which imparts a sour flavor. It also renders kefir nearly lactose-free, which means that many people who can't tolerate milk, yogurt or other dairy products will be able to consume kefir without physical consequences. For individuals who don't use milk, non-dairy versions of kefir -- made with coconut milk, coconut water, rice milk and even fruit juices -- are available. However, these don't have the same amount of protein as milk-based kefir and have a somewhat different probiotic profile.

A number of health benefits are being attributed to the combination of probiotics, prebiotics and beneficial yeasts that kefir contains. In addition to supporting a healthy gut, studies have found that kefir, which contains upward of 30 different strains of bacteria and yeasts, has anti-inflammatory and anti-microbial properties. Other studies have suggested that kefir can boost immune response, and may even have anti-carcinogenic effects. It's important to note, however, that these are small studies with numerous caveats attached. Much more research is needed before making the leap from observation to medicinal claims.

If you do decide to work kefir into your diet, be sure to read the nutrition labels. The flavor of plain kefir ranges from tart to mouth-puckering. As a result, many brands add sugar, fruit and other flavorings to make it more palatable. Consider the fat, calories and carbohydrates you'll be adding to your daily total and adjust accordingly. And as with any food, don't go overboard. Add kefir to your diet gradually and see how you feel.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)