TABLE 1.

Animal studies of VNS in post-stroke upper limb function.

References	Animal models	Device	Parameters	Stimulation site	Main findings
Porter et al., 2011	Adult female SD rats	Implantable VNS	30 Hz, 0.8 mA, 100 us, 500 ms, biphasic pulse	Left cervical Vagus nerve	Repeatedly VNS paired with a particular movement generate a specific increase in the motor cortex representation of that movement
Khodaparast et al., 2013	Adult female SD rats	Implantable VNS	30 Hz, 0.8 mA, 100 us, 500 ms, biphasic pulse	Left cervical Vagus nerve	VNS paired with rehabilitative training enhance recovery of forelimb force
Khodaparast et al., 2014	Adult female SD rats	Implantable VNS	30 Hz, 0.8 mA, 100 us, 500 ms, biphasic pulse	Left cervical Vagus nerve	Pairing VNS with rehabilitation can make the forelimb function recovered to pre-lesion level, while rehab training alone and delivering the same amount of stimulation after rehab fail to restore forelimb function to pre-lesion level
Hays et al., 2016	Female F344 rats, aged 18 months	Implantable VNS	30 Hz, 0.8 mA, 100 us, 500 ms, biphasic pulse	Left cervical Vagus nerve	VNS combined with rehabilitative training improves motor recovery after ischemic stroke in aged rats
Khodaparast et al., 2016	Female 4-month-old SD rats	Implantable VNS	30 Hz, 0.8 mA, 100 us, 500 ms, biphasic pulse	Left cervical Vagus nerve	VNS paired with rehabilitative training results in the significantly greater recovery of forelimb function in subjects with chronic ischemic stroke and may yield long-lasting benefits