If you've ever wondered why the supermarket toilet paper aisle features more puppies and kittens than a pet shop, it's because of people like Simon Preece and the ancient, reptilian part of your brain.
You know that the puppies and kittens are supposed to make you buy the products - and you think you're not falling for it.
Simon knows how to make sure you do.
Preece is a brand consultant - his title is "head of effectiveness stuff" at multi-award winning UK brand design consultancy Elmwood.
His job is to design product packages that make people want to buy them.
To do this, Preece and his team use pioneering tools that employ how the human brain works at its most basic emotional level.
The tools are called biomotive triggers, and they are the latest development in the field of sensory marketing.
Biomotive triggers use understanding of the brain's primal responses - like fight-or-flight and the nurturing instinct - to create a product that makes consumers respond, whether they know it or not.
Those puppy eyes gazing out from the eight-pack of toilet paper aren't just a cute picture: everything from the size of the eyes to the angle of the dog's head and how it sits, a little mournfully, in the bottom corner of the pack is calculated to send a message of "take me home".
"As long as you are a human being you will respond to certain stimulus in a given way," Preece says.
"They are subconscious and they generate emotion and action without the conscious side of the brain clicking in - so what we basically appeal to is the reptilian part of the brain."
Biomotive triggers were developed from the work of an Australian musician and scientist, Manfred Clynes, who created a theory of "sentic triggers" in the 1970s.
The triggers are expressed in pairs, such as cusps and curves, slender and chunky, agitation and calm.
Cusps - curved points - signal fear and danger, Preece says - think claws and shark's teeth, while curves represent safety and softness.
Cusps grab attention, curves encourage interaction. Each has a purpose for a story a brand wants to tell.
"When we come into this world we're delivered onto our mothers' stomachs, we nuzzle in for our first breastfeed and we're surrounded by curved shapes," Preece says.
"Heavy metal bands write their names in cusps - it says `we're aggressive, we're dangerous'."
Olive oil is an example of slender-chunky: regular oil is in a thick, chunky bottle, while pricey extra virgin is in a tall, slim bottle that says " premium product - pay more".
Enormous amounts of money and creativity are expended on the appearance of products but Preece says a lot of marketing misses something.
"We analyse the consumer like a laboratory rat but we actually forget that at one level we are just human beings," he says.
"We get information overload, so the consumer now is world-class at screening out marketing communication.
"If you are going to cut through you have to be amazing."
Elmwood's biomotive approach has delivered results: in the UK, six years of declining sales for Andrex toilet paper were turned around by rethought packaging that felt and looked classier and used a redesigned puppy photo.
Sales of an own-brand baby moisturising cream jumped 70 per cent after a nondescript bottle was reshaped with curves and a cute cleft to suggest a bub's bottom.
In Australia a packaging redesign for Carman's muesli and bars delivered a big boost in supermarket sales.
Elmwood counts some of the world's biggest brands among its clients, including Nestle, Walmart and Procter and Gamble, while supermarket giant Coles is among the Australian clients.
Sensory design and marketing might sound like elaborate trickery but Preece says that is not the case because if a product is no good, no amount of emotion will help.
"What you can't do is force people to do something against their will," Preece says.
"People will have an emotional relationship with brands - we do it all the time - but what we're working on is help build and design in the feelings that the brands want to communicate.
"At the end of the day consumer has all the power. All you can do is try to engage them."