M1 recruitment during interleaved practice is important for encoding, not just consolidation, of skill memory

Taewon Kim; Hakjoo Kim; Benjamin A Philip; David L Wright

doi:10.1038/s41539-024-00290-2

M1 recruitment during interleaved practice is important for encoding, not just consolidation, of skill memory

NPJ Sci Learn. 2024 Dec 18;9(1):77. doi: 10.1038/s41539-024-00290-2.

Authors

Taewon Kim^{1

2

3}, Hakjoo Kim^{4

5}, Benjamin A Philip⁶, David L Wright⁷

Affiliations

¹ Department of Physical Medicine and Rehabilitation, Penn State College of Medicine, Hershey, PA, USA. [email protected].
² Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania, PA, USA. [email protected].
³ Program in Occupational Therapy, Washington University School of Medicine in St. Louis, St. Louis, MO, USA. [email protected].
⁴ Division of Depression and Anxiety Disorders, McLean Hospital, Belmont, MA, USA.
⁵ Department of Psychiatry, Harvard Medical School, Boston, MA, USA.
⁶ Program in Occupational Therapy, Washington University School of Medicine in St. Louis, St. Louis, MO, USA.
⁷ Division of Kinesiology, Texas A&M University, College Station, TX, USA.

Abstract

The primary motor cortex (M1) is crucial for motor skill learning. We examined its role in interleaved practice, which enhances retention (vs. repetitive practice) through M1-dependent consolidation. We hypothesized that cathodal transcranial direct current stimulation (ctDCS) to M1 would disrupt retention. We found that ctDCS reduced retention due to weakened encoding during acquisition, not disrupted consolidation. These results highlight M1's broad role in encoding and retention of novel motor skills.