Brain and Nervous System

How does physical exercise improve brain health?

DEAR DOCTOR K: You say that physical exercise helps to improve brain health, but it's not obvious to me how that could be. Do researchers understand exactly how exercise helps the brain?

DEAR READER: I understand why that's puzzling. It's easier to see how regular moderate exercise could protect against heart disease, for example. The heart is a muscle, and exercise makes the heart exercise.

Does the Mediterranean diet improve brain health?

DEAR DOCTOR K: I know that the Mediterranean diet is supposed to improve heart health. Recently I heard it also improves brain health. Is that pretty well established? Of all the organs I want to protect, my brain is "numero uno."

DEAR READER: I agree with your priorities regarding organs: My brain is "numero uno," too. And I do think the evidence is strong that the Mediterranean diet does protect the brain. This diet emphasizes fruits, vegetables, grains, beans, nuts, fish, poultry, olive oil and wine.

How can we prevent brain damage during contact sports?

DEAR DOCTOR K: My kids play contact sports. After all the news about how repeated concussions might cause permanent brain damage, I'm worried. Do doctors understand why the brain damage occurs and how to prevent it?

DEAR READER: People have known for a long time that boxers could develop difficulty with thinking, remembering, balance and mood following the end of their careers. The term "punch-drunk" was often used. After all, they're getting hit in the head constantly and are often knocked unconscious.

Do we need to sleep in order to “flush out” our brain?

DEAR DOCTOR K: A friend told me that the reason we sleep is to "flush out" our brain. What is this all about? Is this the reason we sleep?

DEAR READER: Many readers have written asking why we sleep, and we discussed it in yesterday's column. Today we will talk about the recent study that you are asking about, which suggests that one reason we sleep may be to flush out the brain. For those who didn't read yesterday's column, a quick summary. There is evidence that during sleep, our mind and body benefits in several ways. Perhaps most obvious, our muscles get a rest. The fortunate exception is the special muscle that is our heart. We don't want it to quit pumping -- ever!

What is hydrocephalus and how is it treated?

DEAR DOCTOR K: My father had been showing signs of dementia for a few months. We thought it was Alzheimer's disease, but it turned out to be hydrocephalus. What is this, and how is it treated? Does the condition cause permanent brain damage?

DEAR READER: Hydrocephalus is a condition in which extra cerebrospinal fluid collects inside the brain. (Another name for it is "water on the brain.") Cerebrospinal fluid acts as a cushion for the brain and spinal cord. It also supplies nutrients and removes waste products. (I've put an illustration of a brain affected by hydrodcephalus, below.)

I recently had a seizure for the first time, what are the chances I will have another one?

DEAR DOCTOR K: I'm in my mid-30s, and I recently had a seizure for the first time. My doctor recommended anti-epilepsy drugs. Do I really need them? What are the chances I will have another seizure?

DEAR READER: A seizure is a sudden change in the brain's normal electrical activity. During a seizure, brain cells "fire" uncontrollably. There are different types of seizures. Some cause a person to lose consciousness and fall to the ground, twitching or jerking. Then it stops, and a person slowly returns to normal consciousness.

How can I tell if my daughter has a concussion?

DEAR DOCTOR K: Last week my 14-year-old daughter fell while skateboarding. She hit the back of her head and was dazed and had blurry vision for a few seconds. But she felt fine once she sat down and rested a bit. Now the left side of her head hurts, but otherwise she feels normal. Should she see a doctor?

DEAR READER: Yes, she should. In a child, particularly, it is often hard to know when trauma to the head may have caused a brain injury. That's why you should never ignore a head injury, no matter how small it seems. It may sound like I'm overreacting. After all, children bump their heads all the time. And in most cases, this results in nothing more than minor bumps, bruises or cuts in the scalp.

How does Alzheimer’s wreak so much havoc in the brain?

DEAR DOCTOR K: My grandmother has Alzheimer's disease. Over the past few years I have watched the disease take a toll on her judgment, memory, even her personality. How does Alzheimer's wreak so much havoc in the brain?

DEAR READER: In the past 25 years, medical science has learned a great deal about what causes Alzheimer's disease. Before that, we basically knew just that the brains of people with this disease, viewed with a microscope, had some unusual features. We knew that the disease caused brain cells to die prematurely, but we didn't know why. Today, I think we are closing in on understanding some major causes (if not all of the causes) of brain cell death.

Is chocolate actually good for the brain?

DEAR DOCTOR K: Is chocolate really good for the brain?

DEAR READER: It sounds too good to be true, but research has found that certain compounds in chocolate, called cocoa flavonols, may protect brain function. In one recent study, researchers tested the effects of cocoa flavonols in 90 healthy 61- to 85-year-olds with good memory and thinking skills. Participants drank a special brew containing either a low (48 milligrams, or mg), medium (520 mg) or high (993 mg) amount of cocoa flavonols each day.

I have neuropathy pain in my feet. What can I do to relieve it?

DEAR DOCTOR K: I have neuropathy pain in my feet. What can I do to relieve it?

DEAR READER: Neuropathy, or nerve damage, is a remarkably common problem. I get asked lots of questions about it -- both from readers of this column and from readers of the Harvard Health Letter, which I edit. It isn't considered a "major" health problem by many doctors, because it isn't potentially fatal. But, like many other problems not labeled as major by doctors, it sure can make people miserable and interfere with their lives.