BRAIN HEALTH
Brain health is about how the brain works with the body to keep you healthy. Like the heart, the brain is an organ. And like working for heart health, you can work on your brain health too. Dive into brain basics to learn more about your brain.
And if you’re interested in learning much, much more, you can boost your knowledge with a click.
Discover what influences brain health, both positively and negatively, and how you can better or support your own brain health.
BRAIN BASICS
BRAIN CELLS
Neurons or nerve cells send information from the brain and receive information from different parts of the body. Boost your knowledge here.
The electrical impulse, which can be thought of as a tiny surge of electric current, moves through the part of the nerve cell called the axon. This electrical impulse results in the release of chemical messengers called neurotransmitters into the space between two nerve cells. The neurotransmitters float across the gap and carry the impulse or message on to the next nerve cell.
So now we know what happens between nerve cells in the brain, but how exactly does this happen?
Every cell in the body carries an electrical charge that is different to the electrical charge of the tissue surrounding it. The difference between a nerve cell’s electrical charge to its surrounding tissue is called its resting potential. It’s called the resting potential because this is the electrical state of the cell when no other cells are trying to communicate with it, in other words, when the cell is at rest. The resting potential happens because of something called the sodium-potassium pump. This pump is constantly at work to pump positively charged particles (called sodium ions) out of the cell and into the surrounding tissue, while leaving the negatively charged particles (called potassium ions) inside the cell.
When a nerve cell is not ‘at rest’ it is receiving impulses or messages from neighbouring cells. These impulses control the opening and closing of specialised ion channels that are found in the nerve cell’s membrane. These channels allow some ions in, while keeping others out.
The movement of positively and negatively charged ions in and out of a nerve cell’s membrane through the ion channels creates the electrical impulse that travels through the nerve cell. This impulse causes neurotransmitters (or chemical messengers) to be released into the spaces between nerve cells. Neighbouring nerve cells have something called receptors, which receive the neurotransmitters in the same way as a key (the neurotransmitter) fits into a lock (the receptors). Once a nerve cell has sent its electrical impulse, resulting in the release of a neurotransmitter, it returns to its resting potential and waits for a new message from one of its neighbouring cells.
BRAIN MESSENGERS
Neurotransmitters are chemical messengers that allow brain signals or nerve impulses to travel between nerve cells and other cells in the body, eg from your brain to your bicep. Acetylcholine, for example, is involved in motor control, learning and recall. It also enhances memory. Boost your knowledge here.
Two major classes of neurotransmitters are the amino acids such as GABA and glutamate, and the neurotransmitters that are organised into different ‘systems’.
Cholinergic system (running on the neurotransmitter acetylcholine)
Plays an important role in maintaining overall neuronal or nerve activation in the brain. It therefore plays a role in sustained attention, arousal and vigilance. Also important for selective attention and orientating towards important stimuli. May also be involved in memory.
Dopaminergic system (running on the neurotransmitter dopamine)
Plays a role in many areas of thought and emotional processing. Regulating movement, reward-related behaviour, working memory, planning and preparation and problem solving.
Noradrenergic system (running on the neurotransmitter noradrenaline)
Plays a role in arousal and attention, sleep, working memory and long-term memory, especially memories with an emotional component.
Serotonergic system (running on the neurotransmitter serotonin)
Plays a role in arousal, mood, anxiety, aggression, control of eating, sleeping, dreaming, pain, sexual behaviour and memory.
Communication between neurons can be affected or disrupted in several different ways. The side of the synaptic gap (the space between neurons) that releases the neurotransmitters from one neuron is known as the presynaptic side, while the outside edge of the neighbouring neuron is known as the postsynaptic side. The point of contact between the presynaptic side, synaptic gap and the postsynaptic region is called the synapse. Each neuron can have thousands of synapses that connect it to thousands of other neurons. The neurotransmitters once released into the synaptic gap float across this gap into the vicinity of neighbouring neurons. These neighbouring neurons have a region called receptors, which receive the neurotransmitters in the same way as a key (the neurotransmitter) fits into a lock (the receptors).
Ways to disrupt neurotransmitters:
Affecting presynaptic mechanisms
(a) Affecting the amount of neurotransmitter that is produced
(b) Influencing the release of neurotransmitter into the synaptic gap
(c) Influencing the action of autoreceptors (which decreases the release of specific neurotransmitters, depending on the type of autoreceptor)
Influencing the amount of neurotransmitter in the synaptic gap
(a) By affecting reuptake of the neurotransmitter
(b) Stopping the action of substances that break neurotransmitters down
Affecting postsynaptic mechanisms
(a) Administer drugs that copy the effect of neurotransmitters – an alternative key
(b) Administer drugs that block the receptor site to prevent neurotransmitters from binding to that receptor site – jamming the lock
CHANGEABLE BRAIN
This fact is known as brain plasticity. This plasticity is what makes it possible for us to learn a new skill, form new memories and change how or what we think about something! The most common way through which the brain changes is through changes in the synaptic connections between neurons.
One type of plasticity happens when we lose or partially lose input from a specific area of the body (known as sensory input). When sensory input changes, it causes reorganisation of the area/s of the brain previously responsible for dealing with that type of information, to fulfil other purposes. For example, in people who lose their sight, the area of the brain previously responsible for vision becomes involved in tasks related to touch as well as hearing and speech!
THE HEALTHY BRAIN
When the brain is healthy, we can go about daily life with ease and enjoyment. We can manage stress and can concentrate and sleep well. Because a healthy brain works best in terms of memory, movement, skill, sensations and maintaining the whole body. There is much we can do to positively influence our brain health and wellness. Because everything from sleep and stress to exercise and nutrition influences our brain health and vice versa.
THE STRESSED BRAIN
A stressed brain doesn’t work as well in terms of memory, movement, perception, sensations and maintaining the whole body. Sleep disturbances, difficulty thinking, feelings of hopelessness, poor concentration, brain fog – these are some signs of a stressed brain. And an overly stressed brain can lead to mood disturbances, depression, anxiety and a host of physical problems.
8 BUILDING BLOCKS TO BETTER BRAIN HEALTH
SLEEP WELL
GET ACTIVE
EAT RIGHT
KNOW YOUR BODY
MANAGE STRESS
BE SOCIAL
EXERCISE MIND
DISCOVER BRAIN HEALTH
...
‘Cheer up.’ ‘Just snap out of it.’
Well-meaning advice or a careless remark? The things we say about brain health challenges and how we say it can sometimes reinforce the stigma. This makes it harder for people who experience these challenges to speak out and get help, especially when they are already trying their best.
