Related Experiment Video
Updated: May 17, 2026
Automated Multimodal Stimulation and Simultaneous Neuronal Recording from Multiple Small Organisms
Published on: March 3, 2023
Interaction between simultaneously applied neuromodulatory interventions in humans
Siobhan M Schabrun1, Lucinda S Chipchase, Natasha Zipf
1The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, School of Health and Rehabilitation Science, St Lucia, Brisbane, Queensland 4072, Australia. s.schabrun@uq.edu.au
Combining neuromodulatory techniques like transcranial direct current stimulation (tDCS) and neuromuscular electrical stimulation (NMES) does not always enhance effects. Homeostatic mechanisms can block or alter outcomes, requiring careful clinical testing.
Area of Science:
- Neuroscience
- Rehabilitation Medicine
Background:
- Transcranial direct current stimulation (tDCS) and neuromuscular electrical stimulation (NMES) are neuromodulatory techniques with therapeutic potential.
- Concurrent application of tDCS and NMES may activate homeostatic mechanisms that interfere with desired effects on corticomotor excitability.
- The interaction between tDCS and NMES in the primary motor cortex (M1) and its impact on corticomotor excitability remain unclear.
Purpose of the Study:
- To investigate corticomotor excitability following concurrent application of NMES with anodal tDCS (excitatory) or cathodal tDCS (inhibitory).
- To determine if combining tDCS and NMES leads to summative or competitive effects on M1 excitability.
Main Methods:
- Utilized transcranial magnetic stimulation (TMS) to assess corticomotor excitability.
- Compared concurrent NMES with anodal tDCS or cathodal tDCS against control conditions: NMES alone, tDCS alone (anodal/cathodal), and sham stimulation.
Main Results:
- Concurrent NMES and anodal tDCS did not produce summative enhancement of corticomotor excitability, aligning with homeostatic plasticity predictions.
- Combined cathodal tDCS and NMES suppressed NMES-induced excitation, potentially explained by calcium-dependent anti-gating models.
Conclusions:
- The combination of neuromodulatory techniques involves complex interactions.
- Careful evaluation of combined interventions is crucial before clinical implementation to understand their net effects.
