We’ve all made that mistake. A quick trip to the supermarket on an empty stomach ends with a trolley full of fatty, sugary treats that seemed impossible to resist at the time.
It speaks to that old adage about hunger making our eyes bigger than our bellies. But our newly published research finds food cravings can also alter our “mind’s eye” – that mental imagery that enables us to visualise, or even taste, that first bite.
This reflects the fact that, to the human brain, food has always provided a multisensory experience. It can begin with the sight of a crisp pastry or the enticing smell of dinner cooking and roll on with the lingering flavour and texture of the meal we’ve eaten.
Because eating experiences leave imprints in our brains, we can later recreate them with mental imagery that involves every sense. We might imagine the tangy sourness of a lemon on our tongues, or the rich aroma of freshly brewed coffee through our noses.
Intriguingly, we have also discovered that not of all of us can do this in the same way: some can relive sensory experiences in rich detail, while others can only form faint impressions.
Moreover, these abilities don’t appear to be fixed: just how easily we can draw on this mental imagery can change depending on our internal state and motivations.
How food cravings become more vivid
In a series of laboratory experiments run over two sessions at the University of Otago in Dunedin, we observed 60 people who had fasted the night before. One session was run while participants remained hungry and other after were given a full breakfast.
While looking at pictures of different foods, they were asked to imagine either their flavour or texture. They then rated how easy the imagery was to create, how quickly it came to mind and how vivid it felt.
Hunger had a clear effect on flavour imagery. When they were hungry, they found it easier to imagine the taste of food than when they were full. They were also better able to picture themselves eating it and described enjoying it more.
This tells us that, more than just increasing our desire for food, it can enhance how the mind simulates the entire eating experience. It also might explain why food cravings can be so overwhelming, bringing our senses their own banquet of smell, taste and anticipated pleasure.
For those of us who have tried restrictive diets, these findings also shed more light on why willpower alone is sometimes not enough. As hunger increases, thoughts of those foods we crave the most can become more vivid, immediate and rewarding.
In what was perhaps our study’s most surprising finding, our participants were generally able to imagine the texture of foods more easily than their flavours. And interestingly, this imagined sensory experience did not appear to be driven by hunger.
Just why is that distinction important? Imagery related to smell and taste is considered more difficult for us to manifest than visual, auditory or tactile imagery.
Yet the difference we found shows taste and smell imagery indeed has an important role to play – and especially when it comes to food.
Can imagining food change its appeal?
Delving deeper, we decided to find out whether food-related mental imagery might work in another way. Specifically: whether repeatedly imagining eating a certain food could make it more appealing.
Neuroscientists have suggested that the influence this imagery has on our desires and behaviours involves activation of the sensory regions in the brain: a top-down process that mimics the actions of perception itself.
To test this, we carried out a follow-up study in which participants were asked to imagine either the flavour or the texture of a food. We then measured how pleasant they found the food to be – both in the way they’d imagined it before eating and how they felt after eating.
We found that repeatedly imagining a food gradually made the imagined version seem less appealing. However, when participants actually ate the food, they did not enjoy it any less.
This highlights both the power and limits of mental imagery. Repeated imagination can alter our internal representation of a food, but it cannot fully replicate the experience of eating the real thing.
Together, these studies offer new insight into how the body and brain interact during everyday eating. More than simply increasing our desire for food, it can alter how vividly we imagine it. At the same time, mental imagery can influence how appealing those imagined experiences feel.
We live in an environment saturated with food cues, from supermarket displays and product packaging to advertising and social media. As well as affecting what we see, they can also influence what we imagine.
Understanding how hunger and mental imagery work together may help us better recognise the forces influencing our food choices. In doing so, it may offer new ways to navigate a world where temptation is rarely more than a glance, smell or thought away.
