Cash Can Bring Relief From Pain. Literally.

Are you in pain? Forget aspirin - grab some money instead! Money may not buy you love or happiness, but apparently it can bring relief from pain.

In a series of experiments, people who counted money felt less pain when their hands were dipped into scalding water. The soothing power of cash also helped them shrug off the emotional pain of social exclusion.
The findings might offer an easy way to ease life's stings and hurts, from painful medical treatments to social ostracism: Simply flip through a bulging wallet before enduring a painful experience.
"When people are reminded of money in a subtle manner by counting out hard currency, they experience painful situations as being not very painful," said lead author Kathleen Vohs, a consumer psychologist at the University of Minnesota's Carleton School of Management in the Twin Cities.

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This is a concept discussed by Dave Ramsey, cash is emotional, and we have a physical stress reaction when we spend it, and a pleasure reaction when we receive it. That's one of the reasons he recommends using cash (actual paper money) for purchases, because we control spending better when we have that emotional tie.