A U of T Scarborough student has landed a prestigious international grant to do research in understanding the processes behind certain mental health illnesses like anxiety and depression.
Olivia Rennie (BSc, 2018) received a Psi Chi Undergraduate Research Grant for her research using a light-based method to examine the role of the ventral hippocampus in approach-avoidance behaviour. The award is given by Psi Chi, the international Honour Society in Psychology.
Rennie’s work seeks to examine a region of the brain, and corresponding subfields, whose role in approach-avoidance behaviours has been under-examined.
“The hippocampus is well-established as an important structure for learning and memory, but not as much for approach-avoidance behaviour,” says Rennie. Working in the laboratory of Rutsuko Ito, she is looking at specific parts of the ventral hippocampus and how they contribute to approach-avoidance behaviour, using a method called optogenetics, which uses light to examine activity in living cells.
“The really cool thing about optogenetics is that, in contrast to previous techniques, where you couldn’t simply flip a switch and activate or inactivate parts of the brain, with optogenetics you can turn a laser on and deactivate a part of the brain, then turn it off and it’s relieved from that deactivation,” says Rennie. “So you can see changes in behaviour in real time, which is really incredible and very powerful.”
This research is targeting two specific regions, know as CA1 and CA3, within the ventral hippocampus. When inactivated, the CA3 has shown enhanced approach tendencies, which suggests it is involved in regulating avoidance behaviours. In contrast, previous research has found CA1 inactivation to produce the opposite effect—increased avoidance.
There are many psychiatric disorders where approach-avoidance behaviour amplifies negative tendencies. Addiction can be understood as a disorder of enhanced approach where people will use drugs even when they understand the negative consequences. Anxiety and depression can be seen as heightened avoidance.
Insights from this research, which is currently being done on rodents, may help develop new therapeutic methods aimed at treating these conditions.
Rennie is working with Ito, whose lab has been conducting research on approach-avoidance behaviours in the CA1 and CA3 region using different research paradigms. This is their first optogenetics project.