Prenatal growth and early postnatal influences on adult motor cortical excitability.

Objective: Suboptimal prenatal growth may adversely influence motor neurophysiologic development and predispose the individual to greater risk of neurodegenerative disorders in later life. We investigated the influences of prenatal growth and the postnatal environment on motor cortical function in young adults.

Methods: Transcranial magnetic stimulation was used to construct corticospinal stimulus-response curves for 35 young adults (mean age: 28 +/- 0.

Facilitation of cortically evoked potentials with motor imagery during post-exercise depression of corticospinal excitability.

This study examined whether muscle fatigue alters the facilitatory effect of motor imagery on corticospinal excitability. We aimed to determine if post-exercise depression of potentials evoked magnetically from the motor cortex is associated with alterations in internally generated movement plans. In experiment 1, motor-evoked potentials (MEPs) were recorded from two right hand and two right forearm muscles, at rest and during motor imagery of a maximal handgrip contraction, in eight neurologically normal subjects, before and after a 2-min maximal voluntary handgrip contraction.