One of the most intriguing scientific events has occurred recently. Due to optogenetic technology we're learning more about how friutflies behave and how their brains operate now more than ever. The fruitfly like many domesticated primates (humans) has the ability to learn and remember. It is known that the brain of a fruitfly contains about 250,000 cells, and the neural circuitry that controls memories of the past has now been dissected in these insects. Also in a recent study published in the journal Cell, shows that aversive memories are dependent on a tiny cluster of neurons, and also displays that these memories can be imprinted in the fruitfly's brain by using light to manipulate the cells activity.

In recent studies scientists have proven that fruitflies appear to be drawn to some chemicals and repelled by others. These hard-wired preferences may be influenced by experience and learning. Also they've discovered that these insects can easily be trained to become aversive to a specified odor. For example: when an odor is redundantly paired with an electric shock, these flies will learn the association between the two and actually avoid that odor when it next encounters it. Meanwhile if it is exposed to an odor in the absence of the shock, the aversive memory will be extinguished.

The encoding of these olfactory memories is thought to require the actions of the neurotransmitter dopamine on neurons called kenyon cells, which are located in a brain structure called the mushroom body. The kenyon cells also receive olfactory information from the antennae. The fruitfly's brain contains 200-300 dopamine-producing cells, although the direct source of the dopamine signal during aversive reinforcement has yet to be identified.