It's natural for the brain to shrink as a person ages. For most people, the effects aren't very noticeable. However, problems with language and memory and other key functions can develop for those suffering from a disease that causes a serious loss of brain cells, called brain atrophy.
"Brain atrophy — something that happens over time — really starts in an unnoticeable way in early adulthood," says David Weintraub, MD, a neurosurgeon and director of functional neurosurgery at North Shore University Hospital in Manhasset, New York. In time, he adds, you might notice so-called "senior moments," memory lapses referred to as mild cognitive impairment.
Brain atrophy can occur in small areas of the brain or in both hemispheres, according to the National Institute of Neurological Disorders and Stroke (NINDS). Some illnesses cause excessive brain atrophy, most notably Alzheimer's disease and other forms of dementia. Because the tissue in the affected areas of the brain is destroyed, the neurological deficits are permanent.
It Can Affect Speech and Writing
Brain atrophy can cause aphasia, a neurological disorder that affects language skills. According to NINDS, there are four main forms of aphasia, each with different symptoms:
Receptive, or Wernicke's, aphasia, results from damage to the brain's temporal lobe near the ears. You can hear spoken words and see words printed on a page, but can't grasp their meaning.
Expressive, or Broca's, aphasia, results from damage to the frontal lobe of the brain. You have a hard time expressing yourself when speaking or writing, and what comes out is nonsensical speech.
Global aphasia affects both the frontal and temporal lobes and results in the most severe damage. It's possible to lose all language function, both speech and comprehension.
Amnesia, or anomic aphasia, is the mildest form. Its most obvious symptom is not being able to remember the right name for people and things.
Brain Atrophy Due to Dementia
Dementia is another disease that causes brain atrophy, according to the NINDS. Dementia results in memory, language and personality problems. You can have trouble creating and recollecting new memories, trouble with learning and trouble with judgment.
People with dementia may have difficulty reading and writing and, ultimately, an inability to understand language. By the last stage of dementia, people have problems simply tending to their most basic daily needs.
Read more: How Aerobic Exercise Improves Brain Health
Brain Atrophy in Alzheimer’s Disease
Alzheimer's disease is the most common type of dementia, according to the Alzheimer's Association. It can start decades before symptoms appear, but the disease is always progressive and fatal.
One of the most common signs of early Alzheimer's is forgetting recently learned information. Others include forgetting important dates or events, asking the same questions over and over, increasingly relying on memory aids like reminder notes, and needing family members to do things you used to handle on your own. You may experience difficulty making and following plans, doing simple math and concentrating.
Vision and balance problems may also develop. Trouble judging distance and determining color or contrast can result in difficulties when driving. Having trouble communicating and following conversations often leads people with Alzheimer's to pull back from their social life and even beloved hobbies. Poor judgment is another symptom.
People living with Alzheimer's can also have mood and personality changes. They can become confused, suspicious, depressed, fearful, anxious or upset when out of their comfort zone or even at home or with friends.
Read more: 8 Ways to Keep Your Brain Sharp As You Age
Seizures Can Be a Symptom
Seizures also can be a symptom of brain atrophy. They tend to occur when electrical activity in the brain is disrupted, says the U.S. National Library of Medicine. Some people may taste a metallic flavor just before a seizure starts.
Seizures can cause a change in consciousness, ranging from a staring spell to loss of consciousness, it says. Being unconsciousness can lead to confusion or temporary memory loss. It's also possible to lose muscle control and twitch during a seizure. Changes in emotion, such as sudden panic or joy, can also occur with a seizure.