While genetic factors play a part, the actions, learning, and lifestyle choices a person makes all have a role in plasticity – you can regrow brain connections to improve memory and brain function.
Neuroplasticity occurs in the brain at the beginning of life when the immature brain organises itself. Reorganisation of the brain can also occur after brain injury. Throughout adulthood, whenever something new is learnt or memorised, the brain changes to accommodate it.
Extraordinarily, the brain grows by 250,000 neurons per minute prior to birth. The first three years after birth are also a period of incredible growth – a newborn's brain is only about 25% of its adult brain weight, but by the age of three it has grown dramatically by producing billions of cells and hundreds of billions of connections between these cells.
One of the surprising consequences of neuroplasticity is that brain activity associated with a particular function can move to a different brain location. One example is of a surgeon in his 50s suffering a stroke. His left arm became paralysed. During his rehabilitation, therapists immobilised his good arm and hand and then gave him the task of cleaning tables. At first the task was impossible, but gradually the 'bad' arm remembered how to move. He learned to write again, play tennis again and so on. The functions of the brain areas destroyed by the stroke had transferred themselves to healthy areas of his brain. The brain compensates for damage by reorganising and forming new connections between intaact neurons. The key is that in order to reconnect, the neurons need to be stimulated through activity.
For a long time it was believed that as we aged the connections in the brain were fixed – no new neurons, no ability to grow new connections. The wonderful new brain imaging techniques have shown a completely different story. Now we know that the brain never stops changing through learning. Plasticity of the brain is the capacity of the brain to change with learning, as well as growing new neurons. New connections can form and this means new synapses – the name of the tiny structures where neurons join onto one another. Did you know we each have about one quadrillion of these connections?
Incidentally, when you become an expert in a specific domain, the areas in your brain dealing with this type of skill will grow. I remember meeting a very elderly gentleman who was having difficulties with his memory, but he still remembered (and could identify) all the Latin names of any plant he came across. He had been a nurseryman all his working life and this specialist knowledge had developed the associated parts of his brain to the extent the knowledge remained resilient even though he was finding difficulty remembering other things.
Another study showed that learning grows the brain very quickly – it doesn't need months and years of learning to gain the benefit. In a study in Germany, medical students had their brains imaged three months before their final exams and again immediately following the exam. Their images were compared to the brains of students who were not studying for exams at the time. Amazingly, in just those three short months the exam students' brains showed growth in the hippocampus and other brain areas known to be involved in memory retrieval and learning.
So, what can you do right now to activate your brain's ability to grow?
• Keep your brain active with a wide variety of interesting mental activities: puzzles, reading (try reading with your book upside down to give your brain a real workout), memorise your shopping list, put aside the calculator and restore the skill of mental arithmetic.
• Learn a new skill or language. Perhaps an art class (I had a wonderful time observing the extraordinary art of Chan Wan Yiu), ferreting out your family genealogy, or join a book club.
• Discover all you can about your brain and memory. Learn how to take care of it.
• Engage with as many other people as you can. Research shows that social engagement is an important contributor to brain and memory health.
• Exercise – studies over the past ten years have clearly shown that walking most days greatly reduces memory and cognitive decline. That's worth doing!
• Try the memory training videos produced by the Brain and Memory Foundation
• Visit the Brain Fit for Life website and there may be a course near you: http://brainfit.co.nz/
• Be determined to ensure those brain connections are growing!
Dr. Allison Lamont is the founder and clinician at the Auckland Memory Clinic. Read more from Dr Allison Lamont here.