What made me grab coffee at Starbucks over Java Jones in I.V.? Why did I spend so much money on a top at Abercrombie & Fitch on State Street when exactly the same item was cheaper next door? What exactly is the science behind what drives us to buy?

For decades, advertisers, marketers and consumers have held common assumptions about what drives us to buy. Yet many of these beliefs have been shattered by one of the world’s most respected marketing gurus: Martin Lindstrom. In his latest book, Buyology: Truth and Lies About Why We Buy, Lindstrom delves deep into what he calls our buyology (“the multitude of subconscious forces that motivate us to buy”). Someone once said to me “You’ve got to think outside the box to get in the box.” This guy is in the box.

Lindstrom’s exploration was bound to be an eye-opener. Three years, $7 million and teams of men in white coats were spent making it. He used the very latest in neuroimaging technology (fMRI and SST scans) to peer inside the brains of over 2,000 people worldwide. Lindstrom claims that advertisers today know little more than they did a century ago when department store pioneer John Wanamaker proclaimed, “Half my advertising budget is wasted. Trouble is, I don’t know which half.” We learn that eight out of 10 new products launched in the United States are destined to fail in the first three months and in Japan, product launches fail 9.7 times out of 10.

So what are some of Lindstrom’s mind-boggling, brain-teasing revelations? I learned that I, for one, am an unknowing victim of Abercrombie & Fitch’s calculated neuromarketing ploys: the blown-up posters of half-naked models (and the young, sexy, hip crowd that work there or are hired to hang out by the doors), the nightclub atmosphere inside and the distinctive, cloying A&F fragrance that can be smelled a block away. Apparently, my mirror and dopamine neurons (located in the frontal cortex of the brain) are fired by these mind-games and I find myself spending money on merchandise in a subconscious effort to be equally popular and desirable. The cheaper top next door did not tickle my brain, even though it was exactly the same.

Ritual affects us all more than we think (do you check Facebook and your e-mail before starting work?) and both marketing and advertising companies know it. Rituals help our brains form emotional connections with brands and products, to adopt a sense of security, comfort and belonging in an increasingly stressful and uncertain world. Take the Corona-and-lime-wedge ritual. Did it come from Latino culture to enhance taste? A Mesoamerican custom designed to combat germs? Lindstrom cites the ritual as dating back to 1981 when a Californian bartender made a bet with his buddy that he could start a trend.

Buyology reviews the colossal product-placement industry and highlights billion-dollar mistakes. Coca-cola, Cingular Wireless and Ford Motor Company all disperse a mega $26 million a year to feature their brands in the popular TV show American Idol. Cingular and Coca-Cola both pop up repeatedly throughout: the furniture-design emulates a Coca-cola bottle with its rounded contours, contestants enter and exit a room painted an explicitly Coca-cola red and the judges sip cups of the iconic drink. Ford’s advertising assault is featured only off-stage during the 30-second ad spots, and this is where Lindstrom’s brain scanning reveals the billion-dollar blunder. The SST scans tested on four-hundred volunteers found that brands are far more memorable if they play an integral role in the storyline (like Cingular and Coca-cola) since the commercials (Ford) feature in our brains as “just” an ad, making our brains highly likely to filter the featured product.

All this is not to say marketers and advertisers are dropping old methods and running to the science lab. Quantitative and qualitative research, as well as the traditional marketing of products, is still high on the agenda despite their semi-reliability and mixed success rate. Still, the potential of neuroscience to have the final word on the human mind is clear. You may look at things in a different light as you cycle through I.V. in the future. I’ll see you at Starbucks.