![]() ![]() When comparing hands, students will usually find that their dominant hand is faster. How fast it actually happens is called the reaction time. The finger muscle contracts to catch the ruler.The spinal cord sends a message to the hand/finger muscle.The motor cortex sends a message to the spinal cord.The visual cortex sends a message to the motor cortex in the brain.The eye sends a message to the visual cortex in the brain.Explain that in order to catch the ruler a lot of messages have to be passed along different nerves:.Swap positions so that student number 1 can test their reaction time.Ĭonversion Table (modified from Neuroscience for Kids): Distance. ![]() Repeat and get student number 2 to switch hands. Test student number 2 3-5 times (varying the time of dropping the ruler within the 5 second “drop-zone” so they cannot guess when the ruler will fall). Record the level (inches or centimeters) at which they catch the ruler (see table below for conversion into reaction time).Student number 1 will drop the ruler sometime within the next 5 seconds and student number 2 must try to catch the ruler as fast as they can after it is dropped.Student number 2 should put their hand at the bottom of the ruler and be ready to grab the ruler (however, they should not be touching the ruler). Instruct student number 1 to hold the ruler near the end (highest number) and let it hang down.Have students form partners for the activity.Each pair should decide who is number 1 and who is 2.Glue or tape it to a piece of stiff cardboard or ruler (unless printed onto card).Photocopy and cut out the reaction timer (double-check the size is accurate).Why was the ruler caught in the middle (after a lag period) rather than at the end (instantaneously)? What causes this hesitation? What had to happen in your body for you to catch the ruler?ĭoes your reaction time improve with practice? This is a recommended pre-visit activity to Science World.ĭescribe how the nervous system responds to a stimulus.Ĭopy of reaction timer template printed onto stiff card or attached to a ruler with tape The distance the reaction timer travels before you catch it has been converted to time using the equation d=1/2 at² where a is the acceleration due to gravity. But these signals are “involuntary” which means that no matter how hard you try, you cannot control how quickly they occur. (Pain signals for example, move very slowly, often less than one metre per second). Signals for muscle control generally move faster than other ones. Moving at about 100 metres per second, a signal telling a finger to move has to travel from your brain down your spinal cord and into your arm. Much of the time it takes you to react to the ruler dropping is the time it takes electrical signals to travel along your nerves. You can take the time it takes to decide things out of the equation. Practice does make perfect because you can create a “muscle memory” that means you do not have to think so much to catch the ruler. All of these processes involve individual neurons that transmit electrochemical messages to other neurons.Ī person’s reaction time depends on a couple of things that can be improved and a couple that cannot. The final process is the contraction of the muscles as the hand grasps the ruler. The motor cortex sends a message to the spinal cord, which then sends a message to the muscle in the hand/fingers. The visual cortex sends a message to the motor cortex to initiate catching the ruler. After the ruler is dropped, the eye sends a message to the visual cortex, which perceives that the ruler has fallen. Rather, this activity is designed to measure the response time to something that you see.Ĭatching a dropped ruler begins with the eye watching the ruler in anticipation of it falling. The neural pathway involved in a reaction time experiment involves a series of neural processes. This experiment does not test a simple reflex. The whole process takes between 150 and 220 milliseconds. Your finger muscles move to catch the timer. A nerve signal travels from your eye to your brain then to your finger muscles. When your friend drops the timer in the experiment, you see it start to move. In this activity, the students participate in a simple ruler drop experiment and learn about the body’s response behind it. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |