Science and technology

For many individuals, the day doesn't truly begin until they've had their morning cup of coffee. Coffee is widely believed to boost alertness, prompting people to rely on it to wake up and enhance their productivity. However, researchers from Portugal have delved into the effects of coffee consumption to determine whether the perceived wakefulness is a result of caffeine or simply the experience of drinking coffee itself.

Prof. Nuno Sousa, the corresponding author of the study published in Frontiers in Behavioral Neuroscience and the Field Chief Editor of the journal, explained, "There is a common expectation that coffee increases alertness and psychomotor functioning. When you gain a better understanding of the mechanisms underlying a biological phenomenon, you open pathways for exploring the factors that may modulate it and even uncover the potential benefits of that mechanism."

A Caffeine Kickstart

To investigate the effects of coffee consumption, the scientists recruited participants who consumed at least one cup of coffee daily. Before the study, the participants were instructed to abstain from consuming any caffeinated beverages or food for a minimum of three hours. Sociodemographic data was collected through interviews, and the participants underwent two brief functional MRI scans: one before and another 30 minutes after either consuming caffeine or drinking a standardized cup of coffee. During the functional MRI scans, the participants were instructed to relax and let their minds wander.

Based on the known neurochemical effects of coffee, the researchers expected that the functional MRI scans would reveal higher connectivity between networks associated with the prefrontal cortex (linked to executive memory) and the default mode network (involved in introspection and self-reflection). Surprisingly, the results showed that the connectivity of the default mode network decreased both after drinking coffee and after consuming caffeine alone. This suggests that the consumption of caffeine or coffee primes individuals to transition from a resting state to engaging in tasks.

Waking Up on the Right Side of the Bed

However, drinking coffee specifically increased connectivity in the higher visual network and the right executive control network, which are parts of the brain associated with working memory, cognitive control, and goal-directed behavior. These effects were not observed when participants consumed caffeine alone. In other words, if you want to feel not only alert but also ready to tackle tasks, caffeine alone may not be sufficient—you need the complete experience of savoring that cup of coffee.

Dr. Maria Pico-Perez, the first author of the study from Jaume I University, explained, "Acute coffee consumption decreased the functional connectivity between brain regions of the default mode network, a network associated with self-referential processes during rest. The connectivity was also decreased between the somatosensory/motor networks and the prefrontal cortex. Meanwhile, connectivity in regions of the higher visual and right executive control network increased after coffee consumption. In simple terms, subjects felt more prepared and alert to external stimuli after having coffee."

Pico-Perez added, "Considering that some of the effects we observed were also reproduced by caffeine, it is plausible to assume that other caffeinated beverages might share some of these effects. However, some effects were specific to coffee consumption, likely driven by factors such as the drink's particular smell and taste or the psychological expectations associated with consuming it."

The authors of the study acknowledged that it is possible for individuals to experience these benefits from the act of drinking coffee alone, without the presence of caffeine. The study did not distinguish between the effects of the experience itself and the experience combined with caffeine. Additionally, there is a hypothesis that the perceived benefits claimed by coffee drinkers could be attributed to the relief of withdrawal symptoms, which was not explored in this study.

Sousa cautioned, "The changes in connectivity were observed during a resting-state sequence. Any associations with psychological and cognitive processes are interpreted based on the common functions attributed to the regions and networks observed, but they were not directly tested. Moreover, individual differences in caffeine metabolism among participants could be interesting to explore in future research."

As researchers continue to unravel the complex relationship between coffee consumption, caffeine, and cognitive processes, it becomes evident that there is more to the morning coffee ritual than just a caffeine boost. Whether it's the sensory experience, the psychological expectation, or a combination of factors, that necessary morning cup of coffee seems to hold a special place in our daily routine, signaling the start of a productive day ahead.