Competition on supermarket shelves is intense and manufacturers and retailers consistently grapple with how to make their brands stand out. Packaging, advertising, placement and consumers' own goals all come into play. A new study sifts through these factors to offer pointers on which matter most.

Ralf van der Lans, Rik Pieters and Michel Wedel tracked the eye movements of 109 consumers in The Netherlands who were asked to search for brands of laundry detergent on a computer-simulated supermarket shelf. Their attention was also directed to certain formats of the detergent (the stock-keeping units - SKUs), such as tablets and gels, and they had a maximum 10 seconds to find the product.

The authors focused on where the participants' gaze lingered, their accuracy, and how this interacted with the visual characteristics, or "bottom-up effects" of the products including color, luminance and edges. They were also interested in consumer goals, or "top-down effects". These were discerned by the different emphasis people gave to certain features such as color for certain brands, so if a consumer focused more on blue when searching for one brand than another, that was said to reflect his or her goals.

These goals are affected by out-of-store marketing, such as advertising, and the authors were able to use the data to illuminate on the impact of different strategies for making brands salient to consumers.

"We show that about one-third of salience on the shelf is due to out-of-store marketing and two-thirds due to in-store marketing. This underlines that the integration of advertising with packaging strategies should be a key concern. The relatively small top-down influences on salience that we found for some brands may well be attributable to a lack of integration of packaging and advertising strategies for those brands," they said.

The participants had been asked to search for five brands, with a sixth, Ariel, being the market leader and the baseline. But one of the brands, Persil, bore a physical resemblance to Ariel and suffered from a lack of differentiation. Although all five brands became more salient when they were the target of the search, "Persil had a relatively smaller lift of its salience. In fact, when Persil was the target, the SKUs of Ariel became more salient as well and even more so than Persil."

" Consumers did not appear to have a strong memory for the visual image of Persil. Advertising should strengthen the association between Persil and its green color to make it easier to find when it's on consumers' shopping lists."

Another issue was the SKUs. In some cases the tablet and gel forms of the product were difficult to distinguish and the authors suggested that manufacturers should also take care in differentiating their SKUs.

There is a cautionary note. Products cannot differ too much from the "visual codes" of their category (such as red for ketchup) or else consumers may have difficulty locating them.

"The salience of brands has a pervasive effect on search performance, but it appears consumers use only one or two basic features simultaneously when trying to find a brand rapidly and accurately. This has important implications for packaging design and for advertising that aims to increase brand salience on the shelf. Such advertising would need to establish strong association in the memory with a limited number of unique features," the authors said.