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collecting sneakers going places rock climbing skiing	playing basketball movies shopping for cool clothing arts and crafts

Links for 7th grade science project (JK and AL):

1. Brain Plasticity and Learning - a Visual learning activity
2. "Rewiring" the Brain - Original experiment, 18 pgs - PDF (1093 KB)
3. Student Worksheet
4. Advanced extra hypotheses
5. When a person views an object through a prism the object appears to shift its position in space. This is because the rays of light that bring the object into the visual field are bent as they pass through the prism. The result is that the object appears to be in a different spot than it actually is. The object doesn't really move, it only appears to move. This experiment demonstrates one of the fundamentals of the visual process. What we see is sensed by the eye, processed by the brain, and projected into space. The accuracy of our visual perception, the extent to which it matches reality, is dependant not only upon the acuity of our vision, but also on the efficiency of the brain processes that created the images we see. It is important to understand that vision is a brain process of which the eyes are only one component.

6. http://www.sfn.org/cnl/hons.html

We usually throw play-doh (or clay) balls at a small chalk circle on a blackboard. One person throws; another marks where the ball hits, others pickup the balls. If the class is well mannered or more advanced the marker can place numbers for each hit; otherwise, any simple mark will do. A different type of mark should be used for each part of the experiment. The proctor places the balls in the thrower's hand, one at a time. It is important that the thrower not look at his arm (especially during and after the prism goggles have been put on - some online correction can occur if the arm is seen). It is also important that the subject throw approximately the same way every throw (i.e., overhand and about the same speed) since the adaptation appears to be specific to the muscle synergy involved (this can be examined in more detail if the students are interested, see below).

The experiment is done in three stages:

1. The subject throws 10-15 normal throws. I ask a few of the students to watch and assess the throws. After the throws I ask for a summary of what happened. This is an excellent opportunity to stress the importance of observation in science. "Pretty good" is not an acceptable answer, but leads to the question "How can we get an objective summary of the results?" After discussing opinions we usually summarize the throws by drawing a circle around the marks (a measure of variation) and sometimes putting an 'x' at the apparent center of the marks (a measure of the mean).
2. Place the prisms on the subject. It should be emphasized to the subject to throw where they see the target. After they start throwing remind them to keep aiming at the target and not consciously correct their throws. The same method and questions are put to the students as in (1). When the throws go way off, the children may need to be reminded to watch what happens to the subsequent throws. It may take up to 50 throws but eventually the student will come close to hitting the target. (The student's can be asked if the subject is back to normal - after one close ball many will say "yes"; this is where I commonly introduce in a simple way the concept of sampling with reference to the variance circle placed on the board during the normal throws).
3. Take the prisms off the subject and have him throw at the target. There should be a robust adaptation effect with the ball going off to the other side (away from the direction of the error with the prisms on). This is the dramatic and (for the children) unexpected result. After several throws the subject adapts back to normal.

Throughout the experiment I emphasize observation. After reviewing what happened (as seen by the students) hypotheses can be introduced by asking "So can anybody explain what happened?". The emphasis not on reviewing the data but on adding explanation.

There are three main points:

1. We need to have some controls in order to have a baseline to compare the novel state to.
2. When we put the prisms on we make errors, but with practice the body adapts.
3. The adaptation is enduring. After the prisms are removed the change in synergy remains.

Additional ideas for the more interested and/or advanced students:

1. How long will the adaptation persists? If time permits and subjects are abundant, after showing the effect on one subject, have a second subject complete steps 1 and 2 of the experiment. After completing step 2 (throwing with prisms on), take the prisms off and have them sit off to the side with their adapted hand behind their back and watch the other students. After completing with the last student, have this student now complete step 3. An aftereffect should still be seen (We have waited up to 1´ hours and still seen an effect).
2. What is being adapted? For example, after adapting one arm, take the prisms off and see if the other arm shows the aftereffect. How about if the child throws underhand? In neither case should an adaptation be revealed. The adaptation seems to be specific to the muscle synergy adapted, not the gaze alone (W.T. Thach et al., 1992).
3. If numbers were used to mark the throws, then the x-offset for each throw can be plotted. This can reveal the change in behavior to older students who can interpret graphs.

MATERIALS:

Fresnel lens distributors:

• Fresnel Prism and Lenses 1-715-349-2628
• Signet Armorlite 1-800-431-6905

Here are some photos of my favorite team, the Chicago Bulls:

If you want to reach me, you can send an E-mail message to me at jesse@kestenbaum.com