The neuroscience of sadness

Parastoo Hashemi takes the stage at The Royal Institution on Saturday 7 November, from 7.00pm to 8.30pm, for a talk called The neuroscience of sadness. She's an analytical bioengineer, and the whole evening is built around a single, pretty big question: could a simple chemical test one day diagnose mental health problems?

To get there, she traces how we've come to understand depression, starting with three theories from the mid-1900s. There's the monoamine theory, which looks at neurotransmitters like dopamine, serotonin and norepinephrine; the plasticity theory, focused on the loss of neuronal connections; and the inflammation theory, which links immune activation to lowered mood. It's a good way to see how the conversation has shifted over the decades, and where the current research actually sits.

Hashemi's own work is right in the thick of it. She uses ultramicroelectrodes to measure neurotransmitter levels and pioneered fast-scan cyclic voltammetry to get the first real-time measurements of ambient serotonin dynamics. She's a multi-award-winning researcher who earned her PhD at Imperial College London, where she became a Reader in Neural Diagnostics and Therapeutics. Beyond the lab, she's a trustee at Mental Health Research UK, President Elect of the International Society for Monitoring Molecules, and an associate editor for ACS Chemical Neuroscience.

The talk is part of the Ri Autumn 2026 collection at The Royal Institution, founded in 1799 — the place where Michael Faraday worked and ten chemical elements were discovered. It's held in the theatre on the first floor, with step-free access via lift, and Green Park is the nearest station. Tickets are £16 or £10 for a theatre audience, and £7 for Ri Members or Ri Patrons, with the Eventbrite booking fee on top.