Psychologist and neuroscientist Dr. Sabina Brennan is like a personal trainer for the brain. She's on a mission to help us maximise our brain health by making adjustments to three areas: attitude, activity and lifestyle, as she told Séan O’Rourke today. She’s put her ideas down in her latest book, 100 Days to a Younger Brain.

Dr. Brennan says that dementia is on the increase in Ireland. She says one of the factors affecting the rising numbers is an aging population: "Age is the biggest risk factor."

With this in mind, Sabina says there’s plenty we can do to slow the deterioration of our brains by the way we live. This claim is backed by research, which compared the brains of two groups of deceased people, those with a diagnosis of dementia and a control group with no diagnosis of the disease.

Amazingly, the research found many people whose brains were "sick", but they showed no symptoms:

"Amongst his control group were 10 individuals with sufficient pathology, enough Alzheimer’s disease in their brain, but had no diagnosis, and weren’t manifesting any obvious symptoms."

Dr. Brennan explained that subsequent research found that these individuals probably cheated the disease by making lifestyle choices which held back the symptoms.

One of the ways we can maintain good brain health is in our understanding of stress, according to Dr. Brennan: "Stress is not a bad thing. We need stress. Challenge is brilliant for your brain, novelty is brilliant for your brain and you need the stress response to rise to those challenges. So stress in and of itself is good."

So if we actually need stress to thrive, what constitutes an unhealthy level of stress? Dr. Brennan says that long-term stress can actually make parts of your brain smaller:

"Poorly managed chronic stress actually impairs the growth of new neurons and connections in a part of your brain called the hippocampus, which is affected in Alzheimer’s disease and which is critical to learning and memory. So actually it causes a shrinkage there in that part of your brain."

Because of this, Sabina says stress management is crucial, at least where possible. Dr. Brennan acknowledges that bereavement or financial difficulties inevitably cause us worry, but we can still work on our responses:

"If somebody dies, it’s a stressful issue, but you have a certain amount of control over how you respond to that."

She has some bad news for the box-set bingers among us. Too many duvet days may be harmful to your brain health, according to Dr. Brennan: "We hear a lot about too much stress; too little stress is not good for you."

Thankfully, she says the news is actually quite good on the aging front: "Even though our processing speed slows as we age, we’re still just as accurate as the young ones."

If you want to find out more on the signs that don’t indicate dementia and the signs that do need checking with a GP, why new experiences are good for the brain and how loneliness can be bad for brain health, listen back to Dr. Sabina Brennan’s full interview with Seán O'Rourke here.

Dr. Brennan is giving a talk entitled 100 Days to a Younger Brain on Wednesday, February 26, 2020, at 7:30 PM in the Hampton Hotel, Dublin 4.

Dr. Sabina Brennan’s 100 Days to a Younger Brain is published by Da Capo Press.