Just seeing reminders of coffee can stimulate us

Simply looking at something that reminds us of coffee can cause our minds to become more alert and attentive, scientists say.

The study, published in the journal Consciousness and Cognition, looks at an effect called priming, through which exposure to even subtle cues can influence our thoughts and behaviour.

"Coffee is one of the most popular beverages and a lot is known about its physical effects," said Sam Maglio, an associate professor at University of Toronto in Canada.

"Much less is known about its psychological meaning -- in other words, how even seeing reminders of it can influence how we think," said Maglio.

"People often encounter coffee-related cues, or think about coffee, without actually ingesting it," he said.

"We wanted to see if there was an association between coffee and arousal such that if we simply exposed people to coffee-related cues, their physiological arousal would increase, as it would if they had actually drank coffee," he added.

Arousal in psychology refers to how specific areas of the brain get activated into a state of being alert, awake and attentive. It can be triggered by a number of things, including our emotions, neurotransmitters in the brain, or the caffeinated beverages we consume.

In this case the researchers wanted to explore how simply being exposed to things that remind us of coffee may have an effect on arousal.

Across four separate studies and using a mix of participants from western and eastern cultures, they compared coffee- and tea-related cues. They found that participants exposed to coffee-related cues perceived time as shorter and thought in more concrete, precise terms.

"People who experience physiological arousal -- again, in this case as the result of priming and not drinking coffee itself -- see the world in more specific, detailed terms," said Maglio.

"This has a number of implications for how people process information and make judgments and decisions," he said.

However, the effect was not as strong among participants who grew up in eastern cultures. Maglio speculates that the association between coffee and arousal is not as strong in less coffee-dominated cultures.

Next steps for the research will look at associations people have for different foods and beverages, researchers said. Just thinking about energy drinks or red wine, for example, could have very different effects on arousal.