Your Brain
Franklin Institute, Philadelphia. Ongoing (general admission: children ages three to 11, $14.50; adults, $18.50)

Lights flash as you scramble through a two-story maze of netting. The netting, which represents our neural pathways, lets you experience your brain on a microscopic level: from the perspective of a neurotransmitter passing from a neuron's axon to its dendrite. With each flash, you know that the neuron in which you are clambering has fired.

As you scale this jungle gym—the Franklin Institute's Neural Climb—you are becoming acquainted with the way information travels through the brain. This interactive structure is a highlight of the institute's new permanent exhibit, Your Brain, which opened last June.

Neural Climb is one of a series of displays on how the brain works. Hands-on activities allow visitors to move a model of a brain scanner to view MRI images of the brain and to launch Ping-Pong balls in a demonstration of neurotransmitters rushing from a neuron when it fires. Galleries early on explore the basic elements of the brain—neurons, neural pathways, brain regions and their functions—and later rooms build on this knowledge, focusing on our five senses. In these subsequent galleries, visitors encounter optical illusions; learn how the brain fills in the gaps when, say, a train conductor's announcement gets garbled; and come to understand how something they cannot see can be found—for example, locating a fly by tracking the changing volume of its buzz.

Each interactive experience generally lasts less than five minutes, in keeping with a child's limited attention span. The blurbs on the walls are also short, aiming more to spark curiosity and conversation than to instruct visitors in complex biological phenomena. Yet for those willing to fight the impulse to run from one display to the next, the exhibit can provide a solid foundation of how the brain works.

The final gallery attempts to situate this knowledge in a broader context by exploring neurological enigmas, including the nature of consciousness, and ethical issues, such as those that arise around the science of altering memories. If the exhibit has a flaw, it might be that it conveys the impression of a solved science. In reality, the brain remains one of the greatest mysteries known to humankind—one that will require the brightest minds of the next generation to crack.