Related Experiment Video
Updated: Jul 15, 2026
10:19
Studying the Neural Basis of Adaptive Locomotor Behavior in Insects
Published on: April 13, 2011
Spike-timing-dependent plasticity induced in resting lower limb cortex persists during subsequent walking
Gowri Jayaram1, Lynette Santos, James W Stinear
1Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL 60611, USA.
Brain Research
|April 27, 2007
Summary
Paired associative stimulation (PAS) applied to the resting motor cortex enhances lower limb excitability during walking. This transcranial magnetic stimulation (TMS) protocol shows potential for modulating cortical plasticity.
Area of Science:
- Neuroscience
- Motor Control
- Neuroplasticity
Background:
- Paired associative stimulation (PAS) modulates motor cortex excitability via spike-timing-dependent plasticity.
- Previous studies showed PAS during walking bidirectionally modulates cortical excitability.
- The effect of applying PAS to the resting cortex on lower limb motor cortex excitability during walking was unexplored.
Purpose of the Study:
- To investigate if applying PAS to the resting motor cortex increases lower limb motor cortex excitability during walking.
- To compare the effects of PAS applied at rest versus during walking on cortical excitability.
Main Methods:
- Healthy subjects (n=13) underwent three PAS sessions.
- PAS involved 120 pairs of transcranial magnetic stimulation (TMS) and common peroneal nerve electrical stimulation at 0.5 Hz.
- TMS intensity was set relative to the active threshold of the tibialis anterior (TA) during walking.
- Cortical excitability was assessed by measuring TA evoked potentials during walking.
Main Results:
- When PAS was applied to the resting cortex with TMS intensity above the active threshold, TA evoked potentials increased by 124% during walking.
- Applying PAS during the late swing phase of walking with similar parameters increased response amplitude to 114% of baseline.
- PAS applied to the resting cortex at the active threshold intensity did not significantly modulate cortical excitability.
Conclusions:
- Applying paired associative stimulation (PAS) to the resting motor cortex, using TMS intensities above the active threshold, significantly enhances lower limb cortical excitability during walking.
- This resting-state PAS protocol is more effective in increasing cortical excitability during walking than applying PAS during the gait cycle.
- The findings suggest that resting-state PAS can be a potent tool for modulating motor cortex excitability relevant to motor control and rehabilitation.
Related Concept Videos
01:35Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre- and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
01:25Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
Hebbian LTP
LTP can occur when presynaptic neurons...
Hebbian LTP
LTP can occur when presynaptic neurons...
01:23Propagation of Action Potentials
The propagation of an action potential refers to the process by which a nerve impulse, or "action potential," travels along a neuron.
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...
Neurons (nerve cells) have a resting membrane potential, with a slightly negative charge inside compared to outside. This is maintained by ion channels, such as sodium (Na+) and potassium (K+) channels, which control the flow of ions. When a stimulus, like a touch or a signal from another neuron, triggers the neuron, sodium channels open, allowing sodium ions to...