Alzheimer's Disease Archive

Scientists used to think that brain connections developed at a rapid pace in the first few years of life, until you reached your mental peak in your early 20s. Your cognitive abilities would level off at around middle age, and then start to gradually decline. We now know this is not true. Instead, scientists now see the brain as continuously changing and developing across the entire life span. There is no period in life when the brain and its functions just hold steady. Some cognitive functions become weaker with age, while others actually improve.

Some brain areas, including the hippocampus, shrink in size. The myelin sheath that surrounds and protects nerve fibers wears down, which can slow the speed of communication between neurons. Some of the receptors on the surface of neurons that enable them to communicate with one another may not function as well as they once did. These changes can affect your ability to encode new information into your memory and retrieve information that's already in storage.

Many people with hearing loss also have tinnitus, commonly known as ringing in the ear. This phrase is misleading, however, because some people hear ringing while others hear whistles, chirping, or a combination of sounds. Regardless of the particular sound, the distinguishing feature is that it doesn't have an external cause. People with tinnitus hear sounds that people around them don't hear. This isn't to say that tinnitus isn't real—researchers at the National Institute on Deafness and Other Communication Disorders have detected changes in brain activity that occur with tinnitus.

Strategies that can help

Some people with hearing loss and tinnitus find that both problems improve after they get a hearing aid or have a cochlear implant. Others find that their tinnitus symptoms improve somewhat when they cut down on caffeine and alcohol, reduce the amount of fat in their diets, and quit smoking. The following techniques may also help reduce your tinnitus symptoms:

Looking at a screen too long may lead to computer vision syndrome.

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There are many reasons to restrict the amount of time you spend in front of an electronic screen. For example, more hours sitting at a computer or smartphone means fewer hours of being physically active, and looking at a computer screen at night can stimulate the brain and make it difficult to fall asleep.

Here's another reason to curb screen time: a problem called computer vision syndrome — an umbrella term for conditions that result from looking at a computer or smartphone screen. "It's most prevalent with computers, and typically occurs when looking at a screen at arm's length or closer," says Dr. Matthew Gardiner, an ophthalmologist with Harvard-affiliated Massachusetts Eye and Ear Infirmary.

News briefs

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New cases of hepatitis C — a viral infection that attacks the liver — are at a 15-year high, according to surveillance data from the CDC released online May 11, 2017. The CDC estimates that there were about 34,000 new cases in 2015. Young adults (ages 20 to 29) account for most of the new infections, and the CDC attributes this to needle use from opioid addiction. But baby boomers (those born between 1945 and 1965) make up three-quarters of the 3.5 million people living with hepatitis C in the United States. Baby boomers are also the ones dying most often from the virus. New medicines can cure hepatitis C infections in as little as two to three months.

The CDC urges you to get a screening test for the virus if you were born between 1945 and 1965. Anyone who has used illicit intravenous drugs, had more than one sex partner, or who had a blood transfusion before 1992 also should get the test.

Sometimes pain has a purpose — it can alert us that we've sprained an ankle, for example. But for many people, pain can linger for weeks or even months, causing needless suffering and interfering with quality of life.

If your pain has overstayed its welcome, you should know that you have more treatment options today than ever before. Here, we've listed eight techniques to control and reduce your pain that don't require an invasive procedure — or even taking a pill.

It's no secret that alcohol affects our brains. Although excessive drinking is linked to an increased risk of dementia, decades of observational studies have indicated that moderate drinking has few ill effects. However, a recent British study seems to have bad news for moderate drinkers.

On call

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Q. I've noticed recently that I sweat excessively, regardless of the temperature. Should I be concerned?

A. Your genes can determine whether you sweat a lot, but a sudden change in your regular sweating may suggest an underlying condition. Sweating is regulated by your nervous system and can be triggered by a number of causes. The primary signal for perspiration originates in the brain in response to a temperature-related or emotional cue, and then is carried by the autonomic nervous system to the sweat glands in the skin.

A Harvard Medical School doctor answers a common eyesight question

Q: Recently, I started to notice tiny threadlike shapes in my field of vision. My doctor says they are "floaters." Should I be concerned?

A: "Floaters" is a catchall term for what look like dots, threads, or cobwebs drifting across your line of vision.

If you suffer from anxiety, the constant, nagging feelings of worry can be troubling and hard to control. These feelings are usually intense and out of proportion to the actual troubles and dangers in your everyday life. They can make it hard to function at home, at work, or in social situations.

Anxiety can be treated with medication, but several mind-body approaches may also be effective.