Fruit Flies, Personal Space Under The Microscope

Fruit flies with too little dopamine keep their distance from each other. Photo courtesy of

Fruit flies are helping researchers at Western University to better understand the human need for personal space, and could have bigger implications for those with autism or schizophrenia.

Using the tiny insect, researchers led by Western biology professor Anne Simon found social space could be regulated using a neurotransmitter called dopamine. According to the study, different levels of dopamine, a chemical that helps control the brain’s reward and pleasure centers, changed how much space fruit flies need from each other.

Fruit flies are often used by researchers to gain a better understanding of behavior, neurobiology, and diseases because they share much of the same genetic information as humans.

Prof. Anne F. Simon of Western University's Biology Department. Photo courtesy of

Prof. Anne Simon of Western University’s Biology Department. Photo courtesy of

Male fruit flies given too little dopamine needed to get away from each other, while those given too much moved closer to one another. The social distance between female fruit flies increased both with too much or too little dopamine.

“Each animal has a preferred social bubble, a preferred personal space,” said Simon, in a news release issued Wednesday. “If we can connect the dots with other animals including humans — because we all have similar neurotransmitters — we may gain new ways of understanding what’s happening in some disorders where personal space can sometimes be an issue.”

The research team, which includes collaborators from the University of Alabama, will focus their next round of research on how dopamine release is affected by social cues and what happens downstream of the dopaminergic neurons, to identify the circuitry that leads to the decision-making process.

“Ultimately, this research could lead us to understand a little better why some people are averse to social contact,” said Simon. “It might also help us understand why some people who clearly want to interact don’t interpret some social cues the same way others might.”

The paper examining personal space with fruit flies was published Wednesday in the Royal Society journal Biology Letters.