My family is of British heritage so having a cup of tea in my house growing up was customary. Unfortunately, I am not sure if I tasked my mum with conducting this tradition today, she would remember all the steps required to complete it.
That is because a seemingly menial task, like making a cup of tea, is actual a complicated series of activities undertaken by the brain to turn a simple idea into a completed action. Different parts of the brain have to work together to control thinking, learning and remembering.
The brain has 100 billion nerve cells (neurons). Each nerve cell connects with many others to form communication networks. The networks are responsible for the way the brain's messages are relayed and form the basis of memories, thoughts and feelings.
For someone suffering from dementia, amyloid plaques and neurofibrillary tangles deprive the neurons of oxygen, rendering them unable to communicate, and eventually leading to the death of the nerve cell. As the nerves cells die, the brain shrink resulting in simple tasks in daily life like brushing one's teeth becoming too convoluted.
A simple example from daily life that shows how functions controlled by different parts of the brain work together is the task of making a cup of tea.
First you have a thought, I feel like having a cup of tea. Now a whole series of activities have to happen in different parts of the brain before you can enjoy that cup of tea.
The brain has to:
- switch on your motor to make you get up and go to the kitchen;
- remember where the tea bags are stored;
- recognize what container looks like and understand that the label has a connection to the contents;
- recall and understand entire sequence of actions for making tea
(i.e., grab a cup, locate a teaspoon, put the tea bag in the cup);
- connect the visual image of the tap with the activity of running water;
- know the right amount of water has to be measured;
- know how to turn on the kettle;
- exercise patience while the kettle to boils;
- recognize when the procedure has finished;
- know that the boiling water has to be poured over the tea bag and left to steep.
- know to remove tea bag from the cup;
- remind you to put in milk and sugar if that is your preference;
- tell you to raise the cup up to your mouth in order to drink; and
- tell the part that controls the reflex action of swallowing to function correctly.
And now you have your cup of tea to enjoy! Not as menial of a task after all.
Alzheimer's Disease affects not only the individual's ability to initiate and follow a process like this, but also the ability to recognize that a process like this if required.
So next time you go to make your morning pick-me-up, remember how lucky you are to have the mental capacity to be able to complete
To learn more about how dementia affects the brain, take a tour.