Premium
Functional brain changes associated with cognitive trajectories determine specific tDCS‐induced effects among older adults
Author(s) -
VaquéAlcázar Lídia,
AbellanedaPérez Kilian,
SoléPadullés Cristina,
Bargalló Núria,
VallsPedret Cinta,
Ros Emilio,
SalaLlonch Roser,
BartrésFaz David
Publication year - 2021
Publication title -
journal of neuroscience research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.72
H-Index - 160
eISSN - 1097-4547
pISSN - 0360-4012
DOI - 10.1002/jnr.24849
Subject(s) - transcranial direct current stimulation , functional magnetic resonance imaging , cognition , audiology , psychology , hyperactivation , longitudinal study , working memory , physical medicine and rehabilitation , neuroscience , medicine , stimulation , pathology
The combination of transcranial direct current stimulation (tDCS) with functional magnetic resonance imaging (fMRI) can provide original data to investigate age‐related brain changes. We examined neural activity modulations induced by two multifocal tDCS procedures based on two distinct montages fitting two N‐back task‐based fMRI patterns (“compensatory” and “maintenance”) related to high working memory (WM) in a previous publication (Fernández‐Cabello et al. Neurobiol Aging (2016);48:23–33). We included 24 participants classified as stable or decliners according to their 4‐year WM trajectories following a retrospective longitudinal approach. Then, we studied longitudinal fMRI differences between groups (stable and decliners) and across multifocal tDCS montages (“compensatory” and “maintenance”) applied using a single‐blind sham‐controlled cross‐over design. Decliners evidenced over‐activation of non‐related WM areas after 4 years of follow‐up. Focusing on tDCS effects, among the decliner group, the “compensatory”‐tDCS montage reduced the activity over the posterior regions where these subjects showed longitudinal hyperactivation. These results reinforce the notion that tDCS effects are characterized by an activity reduction and might be more noticeable in compromised systems. Importantly, the data provide novel evidence that cognitive trajectories predict tDCS effects in older adults.