Hands-on Activity: Pupillary Response & Test Your Reaction Time
Educational Standards :
Pre-Req Knowledge (Return to Contents)
Although not required, we suggest students complete the previous unit in the series, Humans Are Like Robots and the previous lessons and activities of this unit, prior to starting this activity.
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
Each group needs:
To share with the entire class:
Introduction/Motivation (Return to Contents)
A reflex is an involuntary and nearly instantaneous movement made by the body in response to a stimulus. In some instances, the body reacts to a stimulus without having to send a signal to the brain. Local nerves process the information from the stimulus and react to it automatically. Reflexes are an automatic defense mechanism from the body.
Can you think of instances in which it would be important for the body to react swiftly in order to protect the body so that it makes sense that it reacts without sending a message to the brain first? (See what scenarios students suggest. Possible answers: Pulling back your hands or limbs quickly from touching something hot, sharp or unknown, to protect the body; changing pupil size as you move from daylight into a tunnel or shady area and back into full sunshine, all the while generating continual vision, making the pupil smaller and/or blinking when objects like balls, branches, dust or other people come too close to the eyes, to protect the eyes.)
What are some human reflexes that you know about or have heard about? (Possible answers, many of them mentioned in the associated lesson: knee jerk reflex [patellar reflex], blinking [corneal reflex], blushing, hands touching hot objects, acoustic reflex, rooting reflex, shivering, vestibule-ocular reflex, sneezing, ankle jerk, biceps reflex, coughing, gag reflex, accommodation reflex [coordinated eye lens shape and pupil size adjustments when looking at a distant object after a near object], and pupillary light reflex.)
Let's do some experimenting to test our own reflexes and reactions.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
Before the Activity
With information provided on the eight presentation slides, oversee students as they conduct two short exercises (10 minutes + 25 minutes) on the pupillary light reflex response and hand reaction times. Have students work in pairs, using the worksheet to guide their testing and data collection.
With the Students
Attachments (Return to Contents)
Assessment (Return to Contents)
Pupillary Response: After the pupillary response exercise, have students discuss their findings in groups, particularly if any differences were observed.
Test Reaction Times: After testing their reaction times, have students share and discuss as a class their findings. Then either have students answer the six Response & Reaction Worksheet results and analysis questions in writing to be turned in for grading or lead a class discussion using the questions as prompts. Consider student answers and/or discussion contributions to gauge their comprehension.
Wrap-Up Quiz: Wrap up the lesson/activity set by administering the three-question post-lesson quiz, provided on slide 8 and as the Human & Robot Reflexes Post-Lesson Quiz attachment to the associated lesson. Answers are provided in the slide 8 notes, and as an attachment in the associated lesson.
Activity Scaling (Return to Contents)
References (Return to Contents)
Dowshen, Steven. What Are Reflexes? Last updated September 2010. Kids Health from Nemours. Accessed April 16, 2013. http://kidshealth.org/kid/talk/qa/reflexes.html
List of reflexes (alphabetical). Last updated November 3, 2012. In Wikipedia, The Free Encyclopedia. Accessed April 16, 2013. http://en.wikipedia.org/w/index.php?title=List_of_reflexes_(alphabetical)&oldid=521175984
Mental chronometry. Last updated March 2, 2013. In Wikipedia, The Free Encyclopedia. Accessed April 16, 2013. http://en.wikipedia.org/w/index.php?title=Mental_chronometry&oldid=541675578
Your Sense of Touch. The Senses, Oracle ThinkQuest. Accessed April 16, 2013. http://library.thinkquest.org/3750/touch/touch.html
ContributorsMarianne Catanho, Sachin Nair, Charlie Franklin, Satish Nair
Copyright© 2013 by Regents of the University of Colorado; original © 2012 Curators of the University of Missouri
Supporting Program (Return to Contents)GK-12 Program, Computational Neurobiology Center, College of Engineering, University of Missouri
Acknowledgements (Return to Contents)
This curriculum was developed under National Science Foundation GK-12 grant no. DGE 0440524. However, these contents do not necessarily represent the policies of the National Science Foundation, and you should not assume endorsement by the federal government.