
Auditory Motor Reaction Time
Bang! The starting gun sounds, and you're off! How quickly can your brain process the sound and send a command to your muscles makes a difference! Maybe that's what helped Usain Bolt! In this experiment, we explore auditory reaction time—the interval between hearing a stimulus and reacting with movement. A brief tone plays, and your brain races to process the cue. Test your auditory-motor response and see how fast you really are!
What Will You Learn?
- How to measure and calculate your own reaction times using muscle electrical activity.
- How long the nervous system takes to process auditory stimuli.
- Compare the auditory processing response with the brains visual processing
- How to quantify and analyze data for scientific experiments.
Background
Humans need to react to many things quickly... a fast approaching ball to your head (visual)! A spider crawling on your neck (tactile)! Or a loud barking dog (auditory)! Does the brain processes these all the same way? We will find out.
Before doing this experiment, please complete the Visual-Motor Reaction Time Lab.
Using the Human SpikerBox and the Reaction Timer, we will precisely measure reaction times. In this experiment, we focus on auditory reaction time—how quickly your brain responds when you hear a tone. By analyzing the time between the sound cue and your muscle movement, we can gain insight into neural processing speeds and can use this to make comparisons to learn about brain pathways.
Procedure
Setup
Plug the Human SpikerBox into your device via USB then connect the Reaction Timer using the orange cable. Make sure the Audio Output is turned On (verify that the built-in speaker is active or that your headphones are connected) and that the other two switches are set to Off.

Hook an arm up to the Human SpikerBox by attaching the two red clips to the stickers on the user’s forearm and the black clip to the sticker on the back of the user’s hand.

Connect the electrode cable to the SpikerBox and ensure the battery is installed correctly. Open the SpikeRecorder software and turn on your SpikerBox.

Experiment
You are all set up! This task is designed for 2 people, so you’ll need a partner. One person will be the experimenter and the other the subject. You will record a Simple Reaction Time—how fast can you react with no distractions?
Have the subject (the one connected to the Human SpikerBox) focus on the Reaction Timer. Explain that their goal is to flex their muscle as quickly as possible in response to an auditory cue. For this experiment, we will use the green button. When the experimenter presses it, a tone will sound from the built-in speaker. If the ambient noise is too distracting, the subject may wear headphones (there is a headphone port and volume control in the Reaction Timeer.
Start recording on the SpikeRecorder App!
The experimenter will press the button 10 times at random intervals. Be sure to vary the timing and cover your fingers so the subject can only react to the sound. When finished, measure the reaction times in SpikeRecorder and calculate the average. Who in your group reacts the fastest?
Results & Analysis
Compare your results with the class. Compare this average class result of the auditory task with that of the visual reaction time. Which is faster? Why would this be?