Why we buy things we don't need

The bright lights of Rotorua Central Mall. Photo / Ben Fraser

If you spent the weekend spending up you're certainly not alone.

And there's a good reason why you probably grabbed that 50 per cent off bargain even though you don't really need it.

But it's not just a case of retailers making us think we've got a bargain. Rather it's all down to how our brains work and what happens when we shop.

According to expert Dr Jenny Brockis one of the reasons we buy things we don't need is because we have a fear of missing out.

Speaking to news.com.au, Dr Brockis, who specialises in brain health said retailers were cashing in on our buying habits.

The Future Brain author said most people got excited buying things with many feeling a great sense of control when they handed their wallet over.

"Our brain reacts to buying things," she said.

"We either feel a sense of satisfaction we have something we want or reward if we're buying for other people."

Dr Brockis also said sales were an effective tool for retailers because shoppers were far more likely to buy something they didn't need.

"That thinking we got such a bargain is what retailers have really honed in on," she said.

"If something is significantly discounted shoppers are far more likely to buy it whereas if it's small discount they're not as drawn to it. Big discounts pique our curiosity."

She said discounts made buying irresistible for some.

Dr Jenny Brockis said our brains loved novelty which partly explains why some people love shopping. Photo / Zahrina Robertson

"The problem is our shopping bias to pay less for a given item can blind us to the fact we actually don't need the item at all or it doesn't suit us or might be the wrong size," she said.

"When it's too expensive the part of the brain called the insula is activated helping us choose not to buy. But when that item is then discounted, the medial prefrontal cortex engages in a tug of war."

According to Dr Brockis, retail therapy is pleasurable because the brain loves novelty and clever displays with colours and textures are deliberately designed to entice us.

"Buying makes us feel good through the release of dopamine, the brain's reward hormone," she said.

"It also makes us want that feeling again and want more.

"We also buy partly because of social status and our brain loves that reward which makes us happy, and this is why retailers will draw us back."

Dr Brockis said it was no secret that the brain loves novelty and reward, and bright colourful displays.

Dr Brockis said this was also why companies like Ikea did so well.

"Ikea have got it down pat," she said.

"There's a reason why you walk 15km to get to what you need only to buy other stuff you don't."

But while shopping makes us happy that feel-good sensation we get from a new purchase doesn't last, which partly explains our constant need to update.

"There's something about feeling rewarded by buying something and it's just stuff but that's why people develop collections and buy things piece by piece," she said.

However Dr Brockis points out that we just don't shop because it makes us happy, and sometimes we buy to please others.

"Taking time to carefully, select a particular present for a special person increase our happiness," she said.

"That's because the pleasure centre in our brain, the nucleus acccumbens is activated more by the giving of a gift than we receive a gift."

Dr Brockis also said some people also felt defined by shopping.

"Where we go to shop and what we shop for reflects who we are and our personality," she said.

Dr Brockis said some consumers could happily spend hours in a book store because that was their passion was and reflected their interests.