Neuroaging through the Lens of the Resting State Networks

Abstract

Resting state functional magnetic resonance imaging (rs-fMRI) allows studying spontaneous brain activity in absence of task, recording changes of Blood Oxygenation Level Dependent (BOLD) signal. rs-fMRI enables identification of brain networks also called Resting State Networks (RSNs) including the most studied Default Mode Network (DMN). The simplicity and speed of execution make rs-fMRI applicable in a variety of normal and pathological conditions. Since it does not require any task, rs-fMRI is particularly useful for protocols on patients, children, and elders, increasing participant's compliance and reducing intersubjective variability due to the task performance. rs-fMRI has shown high sensitivity in identification of RSNs modifications in several diseases also in absence of structural modifications. In this narrative review, we provide the state of the art of rs-fMRI studies about physiological and pathological aging processes. First, we introduce the background of resting state; then we review clinical findings provided by rs-fMRI in physiological aging, Mild Cognitive Impairment (MCI), Alzheimer Dementia (AD), and Late Life Depression (LLD). Finally, we suggest future directions in this field of research and its potential clinical applications.

GABA and glutamate moderate beta-amyloid related functional connectivity in cognitively unimpaired old-aged adults

“…The posterior cingulate and precuneus (PCP) region is a major ‘hub’ in various intrinsic brain networks, and pathological change pertaining to the PCP is a robust finding in preclinical AD (Esposito et al, 2013; Lustig et al, 2003; Sheline et al, 2010; Teipel et al, 2016a). Moreover, as the PCP plays a central role for episodic memory processing, this is consistent with episodic memory typically being first affected when cognitive impairment manifests in the course of AD (Albert et al, 2011; Cieri and Esposito, 2018).…”

Psychoanalysis and Neuroscience: The Bridge Between Mind and Brain

“…During this state of consciousness, the individual is engaged in recording all the information-bodily sensations (somesthesic and vegetative), experiencing free association of stimuli such as thoughts, memories, past experience, inner dialogue, mental images, emotions, day dreaming, planning future events, and other activities. In this state the mind jumps from one thought to another with fluidity and usually with readiness (Cieri and Esposito, 2018). This state of mind, nowadays called Random Episodic Silent Thinking (REST; Andreasen et al, 1995), emphasizes the free and errant nature of this way of thinking, partly in contrast with the engagement of mind during cognitive tasks.…”

Functional Brain Network Connectivity Patterns Associated With Normal Cognition at Old-Age, Local β-amyloid, Tau, and APOE4

“…Moreover, although the PCP is considered to play a central role in various cognitive processes associated with the DMN (Choo et al, 2010;Teipel et al, 2015;Quevenco et al, 2017;Cieri and Esposito, 2018), PCP seed map-related effects observed in this study may nevertheless primarily reflect PCP specific pathology than general alterations of the DMN. Follow-up studies using whole-brain connectivity approaches both at rest and during cognitive tasks may thus expand findings of the current study to investigate the DMN and also other brain networks in the context of AD-risk.…”

“…The posterior cingulate and precuneus (PCP) represents a central node of the DMN needed for memory processing (Sperling et al, 2009;Cieri and Esposito, 2018). β-amyloid load affects the functionality of the PCP in old aged adults with, and without cognitive impairment (Unschuld et al, 2012;Schreiner et al, 2016;Grothe et al, 2017;Quevenco et al, 2017Quevenco et al, , 2019.…”