“Just because people prefer something doesn’t necessarily make it effective for commercial purposes,” Mr. Spangenberg adds. Cinnamon, for example, may smell like holiday time and family togetherness, even to those of us who have never cared for cinnamon. Deploying the same olfactory reasoning, the British toy-store chain Hamleys filled its aisles with the aroma of piña coladas a few summers ago, evidently on the theory that piña colada says “vacation” — if not to children, then to the parents who pay for their toys.

Customer inconvenience can also work to retailers’ advantage. It’s well known that staples like bread and milk are often found at opposite ends of the supermarket, because this forces shoppers to travel the length of the store, past shelves of tempting nonessentials. In a department store, the same logic may guide designers to create store layouts that make it impossible for customers to move far without stopping — to let others pass, for example — thereby increasing the chances that their eyes will come to rest on products they can’t resist. Products that seem conveniently placed, including low-cost items in bins near the entrance, are probably there to coax you through the initial “deliberation phase” of shopping.

According to the theory of “shopping momentum,” as explained by researchers from Stanford, Yale and Duke Universities, we fret far more about whether to buy the first item we purchase during a trip than we do subsequent ones.

PERHAPS the subtlest technique in the salesclerk’s repertory, and a reliable way to turn negative emotions into sales, is known as “disrupt-then-reframe.” The idea is to confuse a potential customer, so as to evoke uncertainty, then rush in and offer a reassuring path through the resulting confusion. In a vivid demonstration of the effect in 1999, the psychologists Barbara Price Davis and Eric W. Knowles sent researchers door to door, selling holiday cards for charity. When they described the price as $3 for one package of cards, 35 percent of people decided to buy. But when they described the same offer in terms of “300 pennies,” and then added a clarifying coda — “It’s a bargain!” — their success rate shot up to 65 percent.

We hunger for what psychologists call “cognitive closure,” and if spending is the solution, so be it.

To stretch the idea slightly, might we think of most holiday shopping ploys as a large-scale exercise in “disrupt-then-reframe”? The music’s too loud, the lights are too bright, the streets, subways and buses are sardine tins. The relentless sensory overload — from the cinnamon smells to the Salvation Army bells — fuels agitation and an impulse to escape. How convenient, then, that there appears to be one obvious route through the chaos: buy that Nintendo Wii or that iPad or that designer perfume — whatever you’ve been wavering over — and be done with it.

We might, and probably should, rail against such techniques. We could choose to shop online, as millions do. But we might also turn our attention within, to ask why it is we’re so bothered by the lights and the crowds, so disturbed by anxiety that we’ll shop in order to make it go away. An alternative might be to cultivate what Buddhists call “nonattachment” — and if the earliest Buddhists tended to practice this in beautiful natural settings, perhaps that’s only because they lacked shopping malls. Stand on a busy downtown street at dusk on a pre-Christmas Saturday with this in mind, and decline to be swayed by the exhortations to spend, and it suddenly becomes a purely exhilarating spectacle, as breathtaking, in its own way, as any waterfall or mountain panorama.

A final truth about holiday shopping and happiness: even those of us who don’t enjoy the experience might be forced to admit that we enjoy disliking it. After all, nobody is forced to wait till December to buy gifts, yet every year we do so in droves, plunging with abandon into the precisely choreographed awfulness the retailers work so hard to perfect. I’m not quite ready to go as far as the poet and historian Jennifer Michael Hecht, who writes that holiday shopping fulfills “an ancient need to gather and tithe, and serves as a modern-day ritual of renewal.” I won’t claim that “The Little Drummer Boy” actually improves my holiday season. But things would feel very strange without him.