Many of us will have nipped to the supermarket to grab a few basics like milk or toothpaste and ended up heading home with a basket, or even a trolley full of items we didn't necessarily need.
You might have convinced yourself the purchases were helpful and will save you from going back again to the shop later that week, or you might have just cursed your impulsive spending habits and moved on.
But an expert has claimed that it's more likely than not that you were being influenced by your surroundings and the supermarket had used subtle psychological tricks to try and get you to shop for longer and thus spend more money.
