This game is about detecting a signal and responding to it by a controlled movement. Of course, this does not happen by itself. Movements are controlled by the central nervous system – the brain, spinal column and the nerves – which gets information from the outside world through your senses: sight, sound, touch, taste and smell.

What happens when you play Speed Test?

1. A button glows on the screen
2. When the light enters your eye, it comes in contact with a chemical called rhodopsin, which is present in the membranes of the cells in the retina (called rods and cones)
3. The light causes a chemical reaction, which creates an electrical current along the cells
4. The electric impulse then reaches the optic nerve and travels to the central nervous system.
5. The goal is the back of your brain, where  the optical lobe is located. This is where your brain interprets what your eyes detect
6. A signal is then sent from the central nervous system through motor neurons to the muscles
7. The signal eventually causes the muscles to contract – your finger clicks the mouse button!

Although it takes some time for the signal to travel along each nerve, the major delay in your reaction time occurs at the junction points in between the different nerve cells that are involved, and between the nerves and the muscles. The junctions between nerve cells are called synapses. To transfer the signal from one neuron to another across the synapse, molecules called neurotransmitters are released from the end of one cell and then move through random motion until they reach the beginning of the next cell.

Ways to improve your results

One way of improving your results could be to shorten the transfer time between nerve cells. As mentioned above, the molecules that are responsible for communication between a neuron and its neighboring neurons are called neurotransmitters. There are neurotransmitters that will help to generate an electric signal at the receiving neuron, and there are others that will inhibit the neuron.

Caffeine and adenosine (please wait for 3D molecules to load... Left-click to rotate, use mouse wheel to zoom, right-click for options)

Caffeine, a molecule that you’ll find in coffee, mimics the neurotransmitter adenosine and can therefore compete with adenosine at its binding sites in the synapse. Since adenosine inhibits the signal, but caffeine doesn’t, the binding of caffeine will improve the transfer time in the synapse.

Does it work? You can test this yourself! Ask someone who drinks coffee to play Speed Test before and after a cup of coffee (or two)  and see if he/she gets a better score after having coffee. Write about your experiences under the Discussion tab to the left.

Another way to improve you results has to do with temperature. Increasing the temperature makes molecules move faster! Since molecules are involved in the transmission of signals in the neurons, the signals should be faster if body temperature is raised.

Perform some experiments to see if it works! Play Speed Test in the morning, when your body temperature is at its lowest. Then do a warm up to raise your body temperature and play again. Did it improve your results?

Let us know by writing about your results under the Discussion tab to the left.