Neuroplasticity In Aging Brains

Introduction

Your brain and nervous system work together to help you navigate life. They're not fixed but can adapt, a quality known as neuroplasticity. Think of it like your brain's ability to change and learn.

Good neuroplasticity is when your brain learns and becomes more efficient, like driving without needing GPS or remembering how to ride a bike easily. But sometimes, this adaptability can work against us, leading to persistent pain where the brain becomes overly sensitive.

On the bright side, neuroplasticity also helps the brain recover from injuries and maintain cognitive function as we age.

Definition of neuroplasticity

Neuroplasticity is like the brain's flexibility – its knack for changing and adapting based on experiences. It's a term that covers how the brain can rearrange or grow its neural networks. This could mean functional adjustments after brain damage or structural changes from learning.

Think of it as the brain's ability to be flexible, not that it's made of plastic. "Neuro" refers to nerve cells, the brain's building blocks, so neuroplasticity is about these cells changing or adapting over time¹. 

Importance of studying neuroplasticity in aging brains

Scientists have known for a while that our brains are pretty tough, thanks to something called neuroplasticity. This means the brain can change and rewire itself. Before, it was thought this ability faded in childhood, but new research shows it continues as we grow older.

This discovery has led to tools to boost neuroplasticity for better brain health as we age. For individuals, it means there are steps we can take to keep our brains fit and maintain good cognitive function.

As we age, our cognitive function can decline, partly because of changes in neuroplasticity and how our cells work. Although normal ageing has subtle effects on the brain, it's nothing compared to the big changes seen in diseases like Alzheimer's and Parkinson's.²

The fact that our brains keep changing even in adulthood is pretty cool. It means they can reorganize and make new connections. Sometimes, they even create new neurons. This isn't just interesting; it's also crucial for recovering from things like strokes or injuries, improving our learning abilities, and strengthening parts of the brain that might be affected by age-related decline.

Impact of aging on neuroplasticity

We all know that as we get older, our thinking skills can take a hit. For many, this decline reaches a point where they can't live independently anymore, usually due to some form of dementia or other brain-related issues.

The fear of losing the ability to live on our own is a big concern as we age. Scientists have been studying ways to help, often by training our brains through practices that focus on specific cognitive skills. They measure improvement, usually in behaviour, but some studies even look at changing how our brains work.

Considering how much people worry about cognitive decline as they age, the question of whether we can fight against it has become an important one.

By aging, our brain's ability to adapt and reorganise, known as neuroplasticity, is significantly impacted. This isn't just about losing neurons; it involves changes in how our brain circuits function and biochemical shifts.

The ageing brain shows signs of struggling with adaptive neuroplasticity, increased vulnerability to neurodegenerative diseases like Alzheimer's and Parkinson's, and various issues like inflammation and altered calcium balance.² 

Despite these challenges, the brain does retain some plasticity in old age. Engaging in activities that stimulate the brain, like cognitive exercises and aerobic training, can help maintain skills and reduce the risk of dementia. There's even a limited ability for new neuron generation in certain parts of the brain, although it happens at a slower pace.

Unfortunately, the aging process also introduces some not-so-great changes in the brain, especially in the hippocampus. This includes increased stress, inflammation, altered gene expression, and reduced ability for neurogenesis (the production of new nerve cells) and synaptic plasticity. All these changes are believed to be linked to the decline in cognitive function as we age.^2,3

Factors influencing neuroplasticity in aging

Aging and how our brains adapt involve various factors:

• Genetic Factors:

Your family history and genes can play a big role. Certain genes linked to Alzheimer's disease might influence how your brain is connected and changes over time.

Some genes also affect brain structure in areas related to language and thinking, impacting intelligence. Genetic factors even influence how quickly your brain morphs over time.³

• Lifestyle Factors:

What you do in your daily life matters. Regular exercise, especially aerobic workouts, is super beneficial for your brain. It boosts factors like BDNF, IGF-1, and VEGF, which are good signs for brain health.

Eating habits matter, too. Caloric restriction, basically watching what you eat, can help protect your brain from the ageing process.

Your social life and how you manage stress also play a part. Being social and handling stress well can lead to positive changes in your brain, promoting well-being.⁴

In simple terms, your genes and how you live your life, from exercise to diet to social connections, all have a say in how your brain adapts and ages.

Helpful therapeutic strategies

To keep our brains in top shape as we age, there are some helpful strategies:

1. Exercise Regularly:

Doing aerobic exercises, like walking or jogging, is a fantastic way to boost blood flow to the brain. This helps your brain adapt and can potentially make you sharper and happier.

2. Train Your Brain:

Keeping your mind active with activities and learning, combined with aerobic training, can really shake things up in your brain. It's like giving your brain a good workout, helping you stay sharp, and reducing the chances of memory problems.

3. Explore Medications: Researchers are also looking into medicines. Some drugs that have been tested on stroke patients, for example, show promise in enhancing brain adaptability. This might be something for healthy older folks too.

4. Encourage Growth of New Neurons:

The idea of growing new neurons in a part of the brain called the hippocampus has also been proposed. Things like learning new things, staying in stimulating environments, exercising, and even certain antidepressants might help with this.

5. Develop Brain-Boosting Drugs:

Scientists are looking into creating small drugs that can reach the brain and encourage the growth of new neurons. This could be a game-changer for treating brain-related issues as we age.^5,6

These strategies aim to fight the negative effects of ageing on our brains and might be useful in protecting against age-related brain problems. It's like giving your brain a toolkit for staying healthy and strong.

Possible side effects and contraindications

While the strategies to boost brain health in ageing have their perks, they also come with some possible downsides:

• Exercise Caution with Exercise: Regular aerobic exercise is great, but especially for older adults, there's a risk of physical injuries. Overdoing it might lead to heart issues, especially if someone has existing heart problems.⁷
• Watch Out for Medications: Using drugs to help the brain sounds promising, but different medications can bring different issues. From mild things like feeling queasy to more serious problems like heart or mental health issues, there's a balance to consider. We need to carefully weigh the risks and benefits.⁸
• Be Cautious with Growing New Neurons: Trying to boost the growth of new brain cells is still pretty new in research. There's a chance it could cause cells to grow out of control or mess with how the brain works, affecting thinking or behaviour.⁹

In all cases, it is crucial to think about the person's overall health, thinking abilities, and physical condition before deciding on the best way to boost their brain health. It's like customising a plan that fits them best.

Summary

• Aging impacts neuroplasticity, influencing both cognitive decline and neurodegenerative diseases.
• Genetics and lifestyle factors (exercise, diet, social connections) play roles in how the brain adapts and ages.
• Strategies include exercise, cognitive training, medications, promoting new neurons, and developing brain-boosting drugs.
• Exercise carries injury risks, medications may have side effects, and promoting new neurons could have unpredictable consequences.
• Designing brain health plans should consider individual health, cognitive abilities, and physical condition, consulting healthcare providers for tailored strategies.