Consciousness in a Cockroach

Consciousness in a Cockroach

This article was written by Douglas Fox and was taken from the December 2006 issue of the Discover Magazine. This article is about a how a neurobiologist at the University of Arizona at Tucson, by the name of Nicholas Strausfeld, has probed the brains structures of cockroaches, water bugs, worms, and shrimp using microscopes, tweezers, and other hand built electronics. Strausfeld and his graduate students conclude that the insects possess "the most sophisticated brains on this planet." Bruno van Swinderen, a researcher at the Neurosciences Institute in San Diego agrees with Stausfeld and finds that insects have higher cognitive functions which are sometimes considered "the remote roots of consciousness."

There are some scientists that seem to disagree with Stausfeld and Swinderen's findings. Gilles Laurent, a neuroscientist at Caltech says, "The evidence that I've seen so far has not convinced me." Another neuroscientist at Caltech argues that we have no idea of what level of brain complexity consciousness stops.

Insect brains can seem primitive because a cockroach has nearly 1,000,000 brain cells compared to the 100,000,000,000 brain cells that humans have. A fruit fly has only 250,000 brain cells. Insects also have impressive information management. They pack neurons into their brains 10 times more densely than mammals do. They also use each brain cell more flexibly than mammals (Fox 1). One example that was given was how a honey bee that possess less than 1 million neurons can travel six miles from its hive, find food, and make a beeline directly home. Few humans would be able to conquer this task even if they were equipped with a compass and a map.

Some more astounding news is that cockroaches could have possibly evolved only once in the history of life. There is a theory that cockroaches and humans could be distant cousins because they both may have inherited the basic blueprint from a common ancestor, Urbilateria. Urbilateria is a bilaterally symmetrical animal that was guessed to have lived 600 million years ago.

To the naked eye, the brain of an insect and a mammal look nothing alike. So one of Strausfeld's Ph.D. students, Christopher Theall, developed his own experiment setup for tapping into a portion of the cockroach's brain known as the mushroom body (Fox 2). The mushroom-shaped brain structure is thought to be analogous to the mammalian hippocampus, a brain component involved in forming memories of places (Fox