Over the past few months at least half of the world’s population has been affected by some form of lockdown due to COVID-19, and many of us are experiencing the impact of social isolation. Loneliness affects both mental and physical health, but counterintuitively it can also result in a decreased desire for social interaction. To understand the mechanics of this paradox, UCL researchers based at the Wolfson Institute and the Sainsbury Wellcome Centre investigated social behaviour in zebrafish. Their results are published in eLife.
Most zebrafish demonstrate pro-social behaviour, but approximately 10% are ‘loner’ fish who are averse to social cues and demonstrate different brain activity than their pro-social siblings. However, even typically social zebrafish avoid social interaction after a period of isolation. PhD students Hande Tunbak and Mireya Vazquez-Prada, Postdoctoral Research Fellow Thomas Ryan, Dr Adam Kampff and Sir Henry Dale Wellcome Fellow Elena Dreosti set out to test whether the brain activity of isolated zebrafish mimics that of loner fish or whether other forces were at play.
To investigate the effects of isolation, the researchers isolated typically social zebrafish from other fish for a period of two days and then compared their brain activity to zebrafish who demonstrated aversion to social interaction without having been isolated. The isolated fish demonstrated sensitivity to stimuli and had increased activity in brain regions related to stress and anxiety. These effects of isolation were quickly overcome when the fish received a drug that reduces anxiety.
Read more at Sainsbury Wellcome Centre
Photo Credit: Tumisu via Pixabay