You just bought peanut butter. You chose the jar because, well, you've always eaten the crunchy variety. In reality, however, something else may have influenced your choice—the product you picked was centrally located on the store shelves.
Researchers tracked eye movements of 67 subjects scanned a 3 by 3 matrix of fictitious brands. The tracking found that consumers tend to focus on the objects in the middle—specifically, five seconds before they make their choice. And they do this for all kinds of products, from vitamins to online movies. The study will be published in December 2012 in the Journal of Consumer Research.
Also, subjects continued to go for the centrally-located brand even if the product was not in the middle of their specific visual field. So it's not in reference to one's view, it is literally about the product being central within the entire shelf layout.
Past studies have shown that people tend to make a lot of choices based on central locations, like choosing the middle bathroom stall in a public washroom, a middle seat at a table, or even the middle items in a series of arbitrary objects.
The test consumers had no conscious awareness that they had chosen centrally located brands. Makes you wonder what you've taken home without realizing why.