Altered functional connectivity of the default mode network by glucose loading in young, healthy participants.
Kenji Ishibashi, Keita Sakurai, Keigo Shimoji, Aya M Tokumaru, Kenji Ishii
BMC Neuroscience May 31, 2018 DOI: 10.1186/s12868-018-0433-0 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental crossover study (within-subject fasting vs glucose loading) Peer reviewed |
|---|---|
| Sample size | 12 |
| Population | Young, healthy adults without type 2 diabetes mellitus or insulin resistance |
| Intervention | Glucose loading |
| Topics | Default mode network |
| Keywords | Neural pathways Humans Glucose Magnetic resonance imaging Brain mapping Adult Female Healthy volunteers Cognitive dysfunction Precuneus Posterior cingulate Resting-State Functional MRI |
| Key findings | DMN functional connectivity in the precuneus/posterior cingulate cortex was significantly lower after glucose loading than during fasting (P = 0.014). The authors suggest this decreased DMN connectivity may account for reduced PC/PCC neuronal activity when plasma glucose is elevated, possibly linking glucose increases to cognitive dysfunction. |
Abstract
Background: The functional connectivity of the default mode network (DMN) decreases in patients with Alzheimer's disease (AD) as well as in patients with type 2 diabetes mellitus (T2DM). Altered functional connectivity of the DMN is associated with cognitive impairment. T2DM is a known cause of cognitive dysfunction and dementia in the elderly, and studies have established that T2DM is a risk factor for AD. In addition, recent studies with positron emission tomography demonstrated that increased plasma glucose levels decrease neuronal activity, especially in the precuneus/posterior cingulate cortex (PC/PCC), which is the functional core of the DMN. These findings prompt the question of how increased plasma glucose levels decrease neuronal activity in the PC/PCC. Given the association among DMN, AD, and T2DM, we hypothesized that increased plasma glucose levels decrease the DMN functional connectivity, thus possibly reducing PC/PCC neuronal activity. We conducted this study to test this hypothesis.
Results: Twelve young, healthy participants without T2DM and insulin resistance were enrolled in this study. Each participant underwent resting-state functional magnetic resonance imaging in both fasting and glucose loading conditions to evaluate the DMN functional connectivity. The results showed that the DMN functional connectivity in the PC/PCC was significantly lower in the glucose loading condition than in the fasting condition (P = 0.014).
Conclusions: Together with previous findings, the present results suggest that decreased functional connectivity of the DMN is possibly responsible for reduced PC/PCC neuronal activity in healthy individuals with increased plasma glucose levels.
Comparable studies
Other randomized controlled trials on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin Healthy volunteers | 2012 | Within-subjects, placebo-controlled, task-free fMRI study | n = 30 |
| The effects of psilocybin and MDMA on between-network resting state functional connectivity in healthy volunteers | 2014 | Placebo-controlled study | |
| Ketamine Decreases Resting State Functional Network Connectivity in Healthy Subjects: Implications for Antidepressant Drug Action Healthy subjects | 2012 | Randomized, placebo-controlled, double-blind, crossover rsfMRI challenge | |
| Antidepressants Normalize the Default Mode Network in Patients With Dysthymia Subjects with dysthymic disorder and healthy control participants aged 18 to 53 years | 2013 | Randomized controlled trial | n = 41 |
| Functional Connectivity Measures After Psilocybin Inform a Novel Hypothesis of Early Psychosis Healthy volunteers | 2012 | Within-subject, placebo-controlled experimental study | n = 15 |
Citations in the library
Cites 3
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- The Brain's Default Mode Network Annual Review of Neuroscience May 4, 2015
- The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial correlation network analysis Neuroimage June 13, 2008