Drinking coffee regularly seems to increase concentration and improve motor control and alertness, causing functional and connectivity changes in the brain, a new imaging study suggests.
Using magnetic resonance imaging, the researchers found that connectivity in the somatosensory and limbic rest states was reduced in regular coffee (CD) consumers compared to non-coffee (MNT) consumers, suggesting an association between coffee consumption and better engine control and monitoring. In addition, dynamic activity in various cerebellar and subcortical areas of the brain increased among CDs, consequently with an improvement in the ability to focus.
Similar structural and connectivity changes were observed in the brains of NCDs after consuming a cup of coffee.
“The message to take home for practicing physicians is that regular coffee intake, by reducing the connectivity of specific brain networks at risk, may be relevant to care / surveillance, with possible implications for learning and memory, and also for motor control, ”he told Nuno Sousa, lead author, doctor of medicine, professor at the Faculty of Medicine, University of Minho, Braga, Portugal Medscape Medical News.
“For the general public, the message to take away is that we now know better how regular coffee intake prepares the brain for action and quick response,” he said.
The study was published online April 20 a Molecular psychiatry.
The authors write that coffee has a “special interest in human health, given its short-term effects on attention, sleep and memory, and its long-term impact on the emergence of different diseases and on a healthy period of aging “. However, despite its “widespread use,” little research has focused on the “effects of its chronic consumption on the intrinsic functional networks of the brain.”
The study “did not aim to measure the beneficial effect against the harmful one caffeine in the brain, where there are several contradictory results, “Sousa said.
Rather, he noted, the researchers ’motivation was to investigate the impact of regular coffee intake on brain connectivity, sometimes described as the“ signature ”of regular coffee consumption.
The researchers compared 31 CDs with 24 MNTs. The groups did not differ in age (range, 19 – 57 years) or in number of years of formal education. However, there were slightly more men than women in the CD group (41.95% vs 33.33%).
In addition to demographic information, the researchers assessed the caffeine consumption habits and habits of the participants. depression, anxiety and stress (determined based on the scales of depression, anxiety and stress).
CDs are defined as those who consumed ≥1 cup of coffee per day; ENTs were defined as those who drank <1 cup per week.
After an ingestion interview, participants were subjected to MRI at rest. For NTMs, the first scanning session was followed by coffee injection and MRI was performed ~ 30 minutes later.
The caffeinated brain
Prior to coffee consumption, among the coffee group, there was a “trend” toward lower functional connectivity (HR) patterns in the components of most brain networks, but only significant differences were found between groups in the networks. somatosensory and limbic, including the right precune and right insula.
The authors note that these effects were linearly associated with the frequency of consumption of caffeinated products.
“It’s important to note that the group differences described narrowed after NCD drank coffee, [which] points to a potential causal link between coffee consumption and the changes described above in lower connectivity, ”they write.
|Pre-vs post-NCD: t value = 1.86, Pg = 0.075||Pre-vs post-NCD: t value = 3.88, Pg <.001,|
|Post-NCD vs CD: t value = −2.89, Pg = .006||Post-NCD vs CD: t value = -1.46, Pg = 0.15|
In a connectomics analysis, performed using a network-based statistical approach, the strongest network connections were found within the thalamus, cerebellum, right postcentral turn, middle left temporal turn, left precentral turn, bilateral caudate and the putamen. After consuming caffeine, individuals in the NCD group had a “profile similar” to that of the CD group.
Mean HR was negatively associated with the frequency of caffeine consumption (Pg <.001).
Dynamic analysis found that a functional subsystem lasted significantly longer on CDs than on NCDs (17.95 ± 18.32 vs 8.95 ± 6.13 sec). An independent dynamic analysis found that lifetime results were positively correlated with the frequency of caffeine consumption (Pg = .012).
“After drinking coffee, both the shelf life and the probability of this state in NCD approached the values observed in CD, with the probability of not being significantly different from CD … while it was significantly higher than that of pre-coffee NCD, ”the report authors said.
There were no significant differences between groups in depression levels. However, among the CD group, stress levels were higher (especially in terms of difficulty in relaxation and nervous arousal), compared with the MNT group (mean, 6.0 vs. 4, 0).
Increased frequency of caffeine use was associated with increased anxiety in men (Pg = .023).
The authors note that the data “represent a contribution to the knowledge of the ‘brain with caffeine’ and how these changes are the basis of the behavioral effects caused by coffee intake, with implications for physiological and pathological conditions.”
Commenting on the study for Medscape Medical News, Astrid Nehlig, PhD, director emeritus of research at the French Institute for Medical Research (INSERM), who did not participate in the study, said that decreased functional connectivity in somatosensory and CD-related networks volunteers “probably represent a more efficient and beneficial pattern of connections, in terms of engine control and alertness.”
They also comment on the study for Medscape Medical News, JW Langer, MD, professor of medical pharmacology, University of Copenhagen, Copenhagen, Denmark, who did not participate in the study, noted that “it also shows a possible link between regular coffee consumption and higher levels of stress and anxiety “.
Although “it’s just an association and not a causal finding, it reminds us that coffee can be a double-edged sword and that some people may react negatively to regular coffee consumption.”
The study was funded by the Institute for Scientific Information on Coffee. Although it did not influence experimental design or data analysis / interpretation. The authors received funding from various sources, as described in the original article. Nehlig and Langer have not revealed any relevant financial relationship.
Psychiatry Mol. Published online April 20, 2021. Full text