No significant longitudinal changes in gray matter volume or cortical thickness in the visuomotor VOIs, and no associations between GM metrics and learning progress¶

Claim · All claims
Evidence · 1 study (2 entries) · causal r1 · q3
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? Neither TIMING nor TIMING×GROUP significantly influenced GMV or aCT in any VOI; a significant GROUP effect on PMd GMV likely reflects a pre-existing baseline difference. → Hehl 2026 q3 i? No association was found between baseline or change in GM metrics and BTT training progress. → Hehl 2026 (2)

Evidence¶

Hehl 2026¶

Hehl, M., Toyonaga, T., Carson, R. E., Dupont, P., Van Laere, K., Swinnen, S. P. & Cuypers, K. (2026). No significant changes in synaptic density and gray matter volume following motor learning—a pilot study. npj Science of Learning. https://doi.org/10.1038/s41539-026-00451-5

q3 · i? · causal · r1

Linear mixed models per VOI on FreeSurfer-derived GMV and aCT (PRE, MID, POST) in the 22-participant pilot, with eTIV as covariate. For PMd there was a significant GROUP effect on GMV (p = 0.0412), which the article says "only indicates a group difference in GMV, probably already existent at baseline".

"Neither TIMING, nor the interaction TIMING × GROUP significantly influenced SUVR in any of the VOIs (main effect TIMING: all,p > 0.10/0.08 for GMV/aCT; interaction effect TIMING × GROUP: all,p > 0.28/0.33 for GMV/aCT)"

Hehl 2026 (2)¶

Hehl, M., Toyonaga, T., Carson, R. E., Dupont, P., Van Laere, K., Swinnen, S. P. & Cuypers, K. (2026). No significant changes in synaptic density and gray matter volume following motor learning—a pilot study. npj Science of Learning. https://doi.org/10.1038/s41539-026-00451-5

q3 · i? · causal · r1

Multiple linear regressions of BTT training progress on baseline and change in GMV and aCT, corrected for eTIV, in the same pilot. Null for each group apart (all p > 0.01 with Bonferroni correction) and pooled (all p > 0.06).

"There was no association between GMV PRE and BTT training progress"

Discussion¶

Related Claims¶

• Baseline cortical thickness in (pre)SMA is positively associated with baseline SV2A tracer binding, but no other VOIs show this relationship and changes in GM are not associated with changes in SV2A binding — related
• No significant longitudinal changes in SV2A tracer binding in six visuomotor VOIs after four weeks of motor learning, and no associations between SV2A binding and learning progress — related
• Exploratory whole-brain voxel-wise analysis reveals a decrease in SV2A tracer binding in the left temporal pole from PRE to POST, to be interpreted with caution — related
• Learning progress (linear slope of progress-test scores) differs significantly between simple and complex training groups for complex subtasks but not the 1:1 subtask