JoVE Encyclopedia of Experiments
Neuroscience
0 views • 4:31 min • August 29th, 2025
Begin with a seated participant wearing an electroencephalography cap to record brain activity.
Electromyographic electrodes are placed over the abductor pollicis brevis muscle in the hand.
Position the transcranial magnetic stimulation coil over the primary motor cortex.
Apply low-intensity pulses to depolarize cortical pyramidal neurons.
These neurons transmit signals to spinal motor neurons, triggering muscle contractions, recorded as motor evoked potentials
Identify the cortical site generating the strongest MEPs.
Adjust the TMS intensity to determine the motor threshold--the minimum intensity required to elicit MEPs.
Optimize the intensity to evoke consistent MEPs.
Move the coil to the dorsolateral prefrontal cortex and stimulate using the optimized intensity.
A single pulse depolarizes cortical pyramidal neurons, inducing cortical excitability.
Next, apply a paired-pulse to activate interneurons, triggering inhibitory neurotransmitter release and suppressing pyramidal neuron activity.
The EEG captures this TMS-induced cortical excitation-inhibition balance.
Instruct the participant to rest and remain comfortable with a relaxed back, hands, and legs. Then to find the hotspot, begin by tar
View the full transcript and gain access to thousands of scientific videos