Task-related measures of short-interval intracortical inhibition and GABA levels in healthy young and older adults: A multimodal TMS-MRS study
K. Cuypers,
S. Verstraelen,
C. Maes,
L. Hermans,
M. Hehl,
K.-F. Heise,
S. Chalavi,
M. Mikkelsen,
R. Edden,
O. Levin,
S. Sunaert,
R. Meesen,
D. Mantini,
S.P. Swinnen
Affiliations
K. Cuypers
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium; Corresponding author. Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Tervuursevest 101, 3001, Leuven, Belgium.
S. Verstraelen
REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium
C. Maes
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
L. Hermans
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
M. Hehl
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
K.-F. Heise
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
S. Chalavi
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
M. Mikkelsen
Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
R. Edden
Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
O. Levin
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium
S. Sunaert
Department of Imaging and Pathology, University Hospitals Leuven, Leuven, Belgium; Department of Radiology, University Hospitals Leuven, Gasthuisberg, UZ, Leuven, Belgium
R. Meesen
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; REVAL Research Institute, Hasselt University, Agoralaan, Building A, 3590, Diepenbeek, Belgium
D. Mantini
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; Brain Imaging and Neural Dynamics Research Group, IRCCS San Camillo Hospital, Venice, Italy
S.P. Swinnen
Movement Control & Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, 3001, Heverlee, Belgium; KU Leuven, Leuven Brain Institute (LBI), Leuven, Belgium
Establishing the associations between magnetic resonance spectroscopy (MRS)-assessed gamma-aminobutyric acid (GABA) levels and transcranial magnetic stimulation (TMS)-derived ‘task-related’ modulations in GABAA receptor-mediated inhibition and how these associations change with advancing age is a topic of interest in the field of human neuroscience. In this study, we identified the relationship between GABA levels and task-related modulations in GABAA receptor-mediated inhibition in the dominant (left) and non-dominant (right) sensorimotor (SM) cortices. GABA levels were measured using edited MRS and task-related GABAA receptor-mediated inhibition was measured using a short-interval intracortical inhibition (SICI) TMS protocol during the preparation and premotor period of a choice reaction time (CRT) task in 25 young (aged 18–33 years) and 25 older (aged 60–74 years) adults. Our results demonstrated that GABA levels in both SM voxels were lower in older adults as compared to younger adults; and higher SM GABA levels in the dominant as compared to the non-dominant SM voxel pointed to a lateralization effect, irrespective of age group. Furthermore, older adults showed decreased GABAA receptor-mediated inhibition in the preparation phase of the CRT task within the dominant primary motor cortex (M1), as compared to young adults. Finally, results from an exploratory correlation analysis pointed towards positive relationships between MRS-assessed GABA levels and TMS-derived task-related SICI measures. However, after correction for multiple comparisons none of the correlations remained significant.
