Nov 27, 2025 13:00:00

Scientists explain how Black Friday manipulates the human brain to make people shop

The Friday following Thanksgiving in the United States (the fourth Thursday of November) is known as

Black Friday , and retailers and online shopping sites hold huge sales around that time. Black Friday sales have become common in Japan in recent years, but Thiel Grotzwergers, a senior lecturer in cognitive neuroscience at the University of Western Sydney, and his colleagues explain the 'scientific strategy to get people to shop' behind this.

Here's what Black Friday sales shopping does to your brain
https://theconversation.com/heres-what-black-friday-sales-shopping-does-to-your-brain-269591

Typically, when making a choice, like 'Should I buy a new TV?' or 'Should I buy a living room table?', the human brain gathers and weighs a lot of evidence for and against a choice. Important factors include price, features, user reviews, budget, and warranty details, and people make a decision once they feel they have enough information. This process takes time, but the more important the decision, the more evidence people want to gather.

However, under pressure, the brain lowers its threshold for the amount of information needed before making a decision. In other words, time pressure encourages us to make decisions faster, with less evidence.

This isn't necessarily a bad thing. In situations like 'I have a potentially poisonous bug on my arm' or 'The fire alarm goes off but I can't see the source of the fire,' it's important to make a decision quickly, because you don't have time to carefully weigh the pros and cons before acting. But during Black Friday sales, this same process can lead to impulse buying.

Black Friday is over in a flash, and people are under time pressure. The brain looks for shortcuts to evaluate options, relying on easy-to-understand numbers like the number of people looking at a product, the number of people who have purchased, and the discount percentage. However, these numbers may be less useful than details like the product's quality, necessity in life, reviews from previous buyers, price, and long-term value.

In addition, Grotzwagers et al. point out that 'Black Friday sales appeal not only to' urgency 'but also to' scarcity '. Not only do Black Friday sales end in a short period of time, but because many people shop at the same time, there is a strong competitive spirit that 'I have to buy it before someone else buys it.'

For example, if you're looking for a TV on an online shopping site and you see information like '8 units left in stock' or '12 people have this item in their cart,' it feels like competition, making you more likely to add the item to your cart before it's too late, even if you didn't intend to buy it right away.

Scarcity also affects how the brain processes information. When something is in short supply, people attribute higher value to that product, regardless of its actual specifications or necessity. They are more likely to assume, 'It must be a good product because everyone else has it in their cart.'

During Black Friday, retailers create an artificial sense of urgency. For example, timers displaying 'hours and minutes until sale ends,' 'low stock' alerts, and 'today only' banners are all designed to create a sense of urgency and scarcity, driving people's brains to make quick decisions. Grotzwergers and his colleagues point out that this increased sense of urgency puts rational thinking on the back burner, and people stop asking themselves, 'Do I really need this?' and start thinking about the risks of missing out.

Grotzwagers and his colleagues offer four tips for maintaining self-control during Black Friday sales:

1. Plan before the pressure comes
By researching what you really need and arming yourself with more information before the sale starts, you'll be able to make informed decisions even when you're under time pressure.

◆2: Set a budget and make it visible
Setting a limit on how much you can spend on each purchase and keeping that budget in mind while you're shopping on Black Friday will help remind your brain that you have a budget limit.

◆3: Take a break before you buy
There's a lot of pressure during Black Friday, so taking a break before you actually make a purchase can help your excited brain calm down.

◆4: Ask yourself: 'Would I still buy this product at full price?'
With all the products and discounts available during Black Friday, it's easy to feel like you have to buy something or you're missing out. Asking yourself, 'Would I want to buy this item at full price?' helps you focus on the product's true value.