Valentine's Day, by tradition, is an opportunity for declarations of love and lust. But will 2009 be different?
Given the economic downturn, is passion too in recession? Or will couples fling themselves into each other's arms to compensate for their inability to spend, spend, spend?
Professor Helen Fisher, of Rutgers University, holds this latter theory.
The sheer stress of money worries in general, and fear of redundancy in particular will, she argues, elevate levels of the chemical dopamine in the brain - and dopamine is associated with romantic love.
"Times of stress can trigger feelings of attraction - quite simply, you're more susceptible," she said.
Professor Fisher's theories are based on a classic 1974 study by Dutton and Aron - in which male subjects walking across a dangerous- seeming bridge were found to be more likely to fall for an attractive woman researcher.
They are currently being reinforced by a flurry of less academic reports.
