Silent periods are brief pauses in electromyographic (EMG) activity following an event such as a peripheral or central stimulus. Cortical, peripheral nerve, and cutaneous silent periods are described below.

Cortical silent periods (CSP)

Contralateral (cCSP)

During voluntary contraction of a muscle, TMS over the contralateral motor cortex can induce a 'silent period' in the EMG signal - a period of lower EMG activity.

Ipsilateral (iCSP)

Silent periods can also be induced by TMS over the ipsilateral motor cortex.

Peripheral nerve silent periods (PSP?)

During voluntary contraction, electrical stimulation of peripheral nerves can induce a silent period.

Cutaneous silent periods (CuSP)

During voluntary contraction, electrical stimulation of the skin and/or digital nerves can induce a silent period.

Measurement

Many different approaches [needs work!]...

Daskalakis et al 2003

Kimberley et al 2009

Hupfeld et al 2020 - "a review of methods and call for consistency"!