TY  - JOUR
AU  - Fromm, Anna Elisabeth
AU  - Trujillo-Llano, Catalina
AU  - Grittner, Ulrike
AU  - Meinzer, Marcus
AU  - Flöel, Agnes
AU  - Antonenko, Daria
TI  - Increased variability in response to transcranial direct current stimulation in healthy older compared to young adults: A systematic review and meta-analysis.
JO  - Brain stimulation
VL  - 18
IS  - 4
SN  - 1935-861X
CY  - New York, NY [u.a.]
PB  - Elsevier
M1  - DZNE-2025-00872
SP  - 1257 - 1265
PY  - 2025
AB  - Healthy aging is associated with a decline in cognitive and motor functions, affecting daily activities and quality of life. Combining transcranial direct current stimulation (tDCS) with behavioral training may be a promising intervention against this decline. However, individual response variability may obscure group-level effects and mislead conclusions about tDCS efficacy. Quantifying this variability is crucial for accurately assessing stimulation effects and understanding individual response factors, like age. Yet, no study has quantitatively compared tDCS variability across age groups. This systematic review and meta-analysis examine age-related variability in cognitive and motor responses to tDCS.Following PRISMA guidelines, we searched PubMed and Cochrane for studies directly comparing young and healthy older adults under similar experimental conditions. Across 19 studies comprising 390 older adults (mean ± SD age: 67 ± 5 years) and 384 young adults (mean ± SD age: 24 ± 3 years) receiving transcranial direct current (tDCS), we quantified behavioral variability using the log-transformed coefficient of variation ratio (lnCVR).Results revealed substantially higher response variability in healthy older compared to young adults during active tES (21 
KW  - Aging (Other)
KW  - Meta-analysis (Other)
KW  - Stimulation effect (Other)
KW  - Transcranial direct current stimulation (tDCS) (Other)
KW  - Transcranial electrical stimulation (tES) (Other)
KW  - Variability (Other)
LB  - PUB:(DE-HGF)16
C6  - pmid:40633904
DO  - DOI:10.1016/j.brs.2025.06.005
UR  - https://pub.dzne.de/record/280028
ER  -