Our minds can change the structure of our brains and influence the way we feel.

At any given time, what we feel is the result of the brain and mind interacting with each other.

But what exactly distinguishes the brain from the mind?

Our minds are our mental processes – our thoughts, wishes and feelings. In contrast, the brain is a highly complex bundle of synapses. So, while the mind is intangible, the brain is physical.

For instance, the brain contains chemicals called neurotransmitters that cause us to feel certain emotions, such as happiness.

However, our conscious experience is the result of a close interaction between brain and mind. In other words, they form an integrated system.

For example, the neurotransmitter dopamine can make us feel excited and energized – sometimes uncomfortably so.

Let's say that you get a promotion at work, and that your brain responds by releasing lots of dopamine. Whether this will cause you to feel happy or anxious depends on your mind, whose job it is to interpret this flood of dopamine.

But the mind's power doesn't end there: it can also alter the brain's physical structure.

Whenever you experience or feel something, this causes neurons to interact – or “fire” – with each other. Over time, these neurons physically change as enduring physical connections are created between them.

This is known as Hebb's Rule, which is neatly expressed in the phrase: “neurons that fire together, wire together.”

An example of this process is the simple act of laughing with friends. Doing this will establish new links in the brain between the neurons responsible for your memory of that moment and those triggering feelings of joy – proof that our mental processes can alter the structure of our brains.

Here's another example. London cab drivers need to memorize complex street maps and routes. Because of this, they develop a larger than average hippocampus – the key area of the brain activated when memorizing and then recalling how to reach a certain location. In other words, their experiences alter their brains.