Alzheimer Brain

Alzheimer’s Inside The Brain

For Cynthia Guzman, a 71-year-old living in Northern California, profound confusion at a stop sign while driving one day about eight years ago was a clear signal that something was wrong. Now retired, the former nurse says, “I didn’t know where I was going. It was like I woke up at the stop sign,” which was a frightening moment. “I was scared and confused.”

She was eventually diagnosed with dementia, and a few years later with Lewy body dementia, a severe form of dementia that can also cause Parkinson’s-like symptoms and hallucinations. She now does a lot of advocacy work for the Alzheimer’s Association (AA), sharing her story so that others might have a better outcome when dealing with dementia.

In all forms of dementia, whether it’s Alzheimer’s disease – which accounts for about 60% to 80% of all cases of dementia – Lewy body dementia or another type of neurodegenerative cognitive illness, the brain undergoes a series of structural and chemical changes. These changes result in the symptoms we identify as dementia, including:

  • Impaired memory.
  • Impaired language and communication skills.
  • A loss of ability to pay attention and focus.
  • A loss of good reasoning and judgment skills.
  • An increase in feeling confused or disoriented.
  • Increased irritability.
  • A reduction in visual perception.
  • A reduction in the ability to care for oneself and attend to the activities of daily living, such as preparing meals, traveling and keeping appointments.

“Alzheimer’s is a decline in cognitive and executive function that’s commonly seen in the older population,” says Dr. Vibhor Krishna, a neurosurgeon at the Ohio State University Wexner Medical Center. Though it may be more commonly seen in people in their 70s and 80s, “it affects many people earlier” and may be called early-onset Alzheimer’s or early-onset dementia when it’s identified in younger adults.

What Happens in the Alzheimer’s Brain?

The National Institute on Aging reports that “the healthy human brain contains tens of billions of neurons – specialized cells that process and transmit information via electrical and chemical signals.” These signals allow you to move and think and do all the normal things you do every day. But in a person with Alzheimer’s disease, this signaling process begins to break down.

The exact cause of that damage – and why it happens to some people and not others – is still under investigation, but a few specific changes to the brain have been observed in people with Alzheimer’s, including:

Understanding Plaques and Tangles

Amyloid protein is “a sticky protein,” Krishna says. It’s produced by the bone marrow and normally aids in fighting infection in the body by surrounding infections, making them easier for the body to fight or remove. But, “there is a mutated form of amyloid in patients with Alzheimer’s, and this amyloid has a tendency to accumulate. And because it’s sticky, it forms these clots,” Krishna explains.

Can Plaques and Tangles Be Cleared?

One theory in the treatment of Alzheimer’s is that if you can slow the accumulation of these structures, you might be able to slow the development of Alzheimer’s disease. Alternatively, if there were a way to break up the plaques and remove the tau protein tangles, you might be able to restore brain function in people who already have a diagnosis. But doing so is anything but easy.

The study is in Phase 1 right now, and Krishna says the team is looking at whether “you can open the blood-brain barrier safely without side effects,” such as brain swelling or micro-bleeding from the tiny vessels in the barrier.