Video Analysis of Motion &
Psychobiology Motion Activities
 
Steve Hammack
Los Gatos High School
Los Gatos, California
 

1. Use of Video Analysis Software to Study Motion.
2. Rewiring the Brain.
3. The McGurk Effect.
 
 
Use of Video Analysis Software to Study Motion

Purpose
To expose biology teachers, and therefore their students, to a powerful tool that can be used in the study of motion.

Materials

Procedure
1. Vidoetape a moving organism.
a. Keep camera in a stationary position.
b. Videotape the organism moving in a straight line perpendicular to the camera.
c. You must know or be able to reasonably estimate the size of the organism.
2. Use the video capture ability of your computer to transfer the image from the videotape into your computer.
3. Use VideoPoint to measure any aspect of the organism's motion: speed, acceleration, center of mass, etc.

Conclusion
The goal of this activity is simply to expose teachers, and therefore their students, to this software tool. It is up to individual teachers to decide how they might use the software, in order to measure the speed of organisms from the tiny ameba to the giant allosaurus.

Other Software
There are several other sources of software that do similar things as VideoPoint. There is a web site that features them all! Click here to check it out.

To top.

Rewiring the Brain

A wonderful activity has been created by Bob Melton of Edmond Memorial High School. It is entitled "Rewiring the Brain" and can be downloaded from the National Association of Biology Teachers web site which has the  Neuroscience Laboratory and Classroom Activities book online.

In the activity a student wears goggles that deviate their vision 15 degrees. The student tosses bean bags (or crumbled papers) at a target until they have "learned" how to hit it despite their deviated vision. They then remove the goggles and try to hit the target and the first few tosses miss the target. It demonstrates that  movement  is controlled by our brains and the neural pathways that control this throwing motion can be temporarily "rewired" . The effect is surprising for the student- they can't believe they will miss the target after they remove the goggles.

The activity can be done simply or in a more sophisticated way. Bob discusses everything you will need to know in his write-up.

Materials

 
 To Top.

The McGurk Effect

The McGurk effect is an auditory illusion in which a listener "hears" a sound that is not acutally produced. The effect is created by videotaping moving lips making a sound and overdubbing a different sound onto the tape. Upon viewing the tape instead of hearing the actual sound or the "sound" that the lips are making, a third sound is heard. The classic version of the effect is to have lip movement indicate "ga" and the actual sound to be "ba". What is heard is something in between the two, "da" or "tha".  It shows that when we hear our brain uses both visual and auditory cues and that these two cues work together to create a particular auditory perception.

Dom Massaro, of UC Santa Cruz,  has published an excellent article  in the American Scientist, May/June 1998, describing the McGurk Effect.  There are a number of excellent internet links at the end of the article.

If you would like to go to a site with a downloadable talking face demonstrating the McGurk Effect then click here.

To Top.