Coffee consumption decreases the connectivity of the posterior Default Mode Network (DMN) at rest

 Well, the whole reason for drinking the vast amounts of coffee I do is to prevent Parkinsons and dementia.This will not change my mind.

I'm doing a 12 cup pot of coffee a day to lessen my chance of dementia and Parkinsons. Tell me EXACTLY how much coffee to drink for that and I'll change.

How coffee protects against Parkinson’s Aug. 2014  

Coffee May Lower Your Risk of Dementia Feb. 2013 

And this: Coffee's Phenylindanes Fight Alzheimer's Plaque December 2018

How Coffee May Protect Brain Health: A New Study Suggests The Benefits Aren't Just From Caffeine December 2018

Caffeine causes widespread brain entropy (and that's a good thing)

April 2018

This Many Coffees(6) Is Bad For Your Heart Health August 2020(I'm ignoring this one)

Study: The More Coffee You Drink, the Longer You Live July 2018 

The latest here:

Coffee consumption decreases the connectivity of the posterior Default Mode Network (DMN) at rest

Maria Picó-Pérez^1,2,3,4†, Ricardo Magalhães^1,2†, Madalena Esteves^1,2, Rita Vieira^1,2,3, Teresa C. Castanho^1,2,3,5, Liliana Amorim^1,2,3,5, Mafalda Sousa^1,2,3, Ana Coelho^1,2, Pedro S. Moreira^1,2,6, Rodrigo A. Cunha⁷ and Nuno Sousa^1,2,3,5*

• ¹Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, Braga, Portugal
• ²ICVS/3B's - PT Government Associate Laboratory, Braga/Guimaraes, Portugal
• ³Clinical Academic Center – Braga, Braga, Portugal
• ⁴Departamento de Psicología Básica, Clínica y Psicobiología, Universitat Jaume I, Castellón de la Plana, Spain
• ⁵P5 Medical Center, Braga, Portugal
• ⁶Psychological Neuroscience Lab, CIPsi, School of Psychology, University of Minho, Braga, Portugal
• ⁷CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal

Habitual coffee consumers justify their life choices by arguing that they become more alert and increase motor and cognitive performance and efficiency; however, these subjective impressions still do not have a neurobiological correlation. Using functional connectivity approaches to study resting-state fMRI data in a group of habitual coffee drinkers, we herein show that coffee consumption decreased connectivity of the posterior default mode network (DMN) and between the somatosensory/motor networks and the prefrontal cortex, while the connectivity in nodes of the higher visual and the right executive control network (RECN) is increased after drinking coffee; data also show that caffeine intake only replicated the impact of coffee on the posterior DMN, thus disentangling the neurochemical effects of caffeine from the experience of having a coffee.

1. Introduction

There is a common expectation, namely among habitual coffee drinkers, that coffee increases alertness and psychomotor functioning. For these reasons, many individuals keep drinking coffee to counteract fatigue, stay alert, increase cognitive performance, and increase work efficiency (Smith, 2002). Coffee beverages are constituted of numerous compounds known to affect human behavior, among which are caffeine and chlorogenic acids (Sadiq Butt et al., 2011). From the neurobiological perspective, both caffeine and chlorogenic acids have well-documented psychoactive actions, whereas caffeine is mostly an antagonist of the main adenosine receptors in the brain—A₁ and A_2A receptors, leading to the disinhibition of excitatory neurotransmitter release and enhancement of dopamine transmission via D2 receptors (Fredholm et al., 2005) to sharpen brain metabolism and bolster memory performance (Paiva et al., 2022); chlorogenic acids can directly impact neuronal performance through mechanisms that still need to be understood (Lorist and Tops, 2003; Fernandes et al., 2021).

While the neurochemical action of these compounds seems to be reasonably understood, the psychological effect of coffee/caffeine, although largely genuine, remains a matter of debate and should be considered in the context of its use. In fact, some studies show that caffeine has effects on cognitive performance and mood if taken by non-habitual coffee drinkers, but that these effects may decline due to the development of tolerance (James and Rogers, 2005). While some studies seem to point to an effect of caffeine in decreasing lethargy/fatigue and increasing vigor (Judelson et al., 2013), others suggest that the cognitive and emotional effects only occur after 8 h of abstinence (Heatherley et al., 2005), and others even point to the fact that a significant component of the psychological effect of coffee/caffeine should be attributable to the reversal of adverse withdrawal effects associated with short periods of abstinence from the intake (James and Rogers, 2005) or even to the suggestion of having had coffee beverages (Liguori and Hughes, 1997; Dawkins et al., 2011).

Only limited information is available about the impact of coffee intake on the whole-brain network activity, for which the use of novel imaging techniques has proven to be of relevance. Functional magnetic resonance imaging (fMRI) allows us to study, in a non-invasive way, the function of the human brain during the execution of specific tasks or at rest (Soares et al., 2016). In the context of coffee consumption, some previous studies show that there is the activation of different cortical and subcortical areas during a visuomotor task (Park et al., 2014), or upon the hedonic evaluation of caffeine and saccharin (Gramling et al., 2019), or of the frontopolar and cingulate cortex during a two-back verbal working memory task (Koppelstaetter et al., 2008; Haller et al., 2017), or in a modified Sternberg task (Klaassen et al., 2013). Moreover, recent studies suggest an impact of coffee on brain functional connectivity at rest prompting a functional reorganization toward more efficient network properties with implications in emotionality, alertness, and action readiness (Kim et al., 2021; Magalhães et al., 2021).

Despite these results, there is still an open question on what drives habitual coffee drinkers to keep drinking coffee. Herein, we aim to explore the resting-state fMRI data in a group of habitual coffee drinkers before and after acute coffee consumption, using network functional connectivity approaches. We hypothesize that coffee consumption will lead to higher integration of networks linked to the prefrontal cortex associated with executive memory and with brain health throughout the lifespan, such as the posterior default mode network (DMN) (Buckner et al., 2009; Leech et al., 2011).