Shoppers to be probed by PS3m brain scanners.
The project will ask selected shoppers to simulate an PS80 grocery shop in a supermarket, while going through a PS3m 20-ton MRI scanner.
A full range of supermarket products are displayed on a screen in front of them and they are asked to make choices from a shopping list while faced with a wide range or promotions and special offers.
The research, to be carried out jointly by retail researchers SBXL and the School of Psychology at Bangor University, will identify which part of the brain is involved in making choices by measuring blood flow and brain activity.
Early findings suggest around 23 minutes into their shop people begin making choices with the emotional part of their brain.
Unlike the cognitive part of the brain, which is capable of computation and logical decision-making, this can only guess at value for money.
Results also show that after 40 minutes - the time taken for a typical weekly shop - the brain gets tired and effectively shuts down, ceasing to form rational thoughts.
The state-of-the-art MRI scanner is based at Bangor University. The equipment was originally developed for identifying brain tumours, defects and dysfunctional activity. But now it is increasingly being used for commercial research.
Senior psychology lecturer at Bangor Dr Paul Mullins said: "Our MRI system allows us to investigate the neural basis of decision making. Using advanced brain imaging techniques we hope to get a better understanding of how shoppers respond to special offers.
"This also gives us the chance to bring our research on decision making into a real-world context, and we hope will tell us a lot about how we respond to different types of competing information in the world around us. In particular we are interested in how factors we may be unconsciously aware of can override what might be considered the optimal choice based on conscious judgements."
Phillip Adcock, managing director of SBXL, said the scanners were an excellent way of building physical evidence which could back up other research findings.
"We know from previous SBXL research that the brain behaves illogically when faced with the sort of information overload that shoppers are faced with in a typical supermarket.
"Previous research has shown us that nearly 20% of shoppers are likely to put special offers in their basket even if they are more expensive than the normal product, and we know that nearly half of shoppers ignore buy-one-get-one-free items and only choose one.
"Now we have a reliable and scientific way of validating this research and understanding exactly what is happening in the brain during the weekly shop," he said.
It's estimated around a quarter of all products on supermarket shelves are on some kind of offer or promotion.
In this context millions are at stake in lost margins for supermarkets if they get it wrong by selling items at reduced cost when customers are happy to pay the full price. SBXL estimates that where unnecessary special offers are made on products that would sell anyway supermarket profits are hit by up to 23% on these mis-promoted items.
SBXL uses techniques such as instore filming to analyse shoppers' behaviour in supermarkets. The firm's research also examines facial expressions and non-verbal communication to identify shoppers' subconscious decision-making.
Further in its quest to profile shoppers the company uses eye-tracking to determine what we see when making our choices.
The research is being paid for by leading grocery and health care firms.