Effects of stimulation of sensorimotor cortex on primate spinothalamic neurons

Central neural influences on the human retina during selective attention

“…The above findings for the auditory system, in conjunction with the well-established fact that centrifugal fibers project to and modulate afferent activity at very early synaptic relays of the proprioceptive (Matthews, 1964), olfactory (Cragg, 1962;Gervais, 1979;Kerr & Hagbarth, 1955;Shepherd, 1970), and somatic (Coulter et al, 1974;Livingston, 1978;Oleson, Ashe, & Weinberger, 1975;Schmidt, 1973) sensory systems lend credibility to the results obtained in the present study for the visual system.…”

“…Evidence obtained from animals indicates that centrifugal activity may alter the flow of incoming information as far peripherally as the spinal cord for the somatic sensory system (Coulter, Maunz, & Willis, 1974) and the olivocochlear bundle for the auditory system (Rasmussen, 1960(Rasmussen, , 1964Oatman, 1976;Oatman & Anderson, 1977, 1980. Recently, Lukas (1980Lukas ( , 1981 reported data which strongly suggest that irrelevant auditory information may be filtered at the level of the olivocochlear bundle in humans, although other attempts to demonstrate such filtering have proved unsuccessful Picton, Hillyard, Galambos, & Schiff, 1971;Picton, Stapells, & Campbell, 1981).…”

Poststroke pain control by chronic motor cortex stimulation: neurological characteristics predicting a favorable response

“…There are somatotopically organized, highly specific MC efferents that project to the somatosensory cortex. 26 The MC and corticospinal tract neurons exert control over sensory transmissions, including signals mediated by spinothalamic pathways, 12 at different levels of the CNS 4,10,35,62 with a strict somatotopic organization. 1,5 Consistent with these findings in experimental animals, Peyron, et al, 51 and Garcia-Larrea and colleagues 17 recently demonstrated in patients suffering from pain that the nociceptive reflex can be inhibited by MC stimulation.…”

Cortical modulation of pain

“…The rationale that guided surgeons to attempt cortical stimulation was based on the results of decades of experimentation showing that electrical stimulation of the cortex changes the transmission of information from both the spinal cord and the trigeminal system supplying sensation to the face [82][83][84]. The analgesic effect is, in part, mediated by presynaptic modulation of somatic afferents [85,[86][87][88], including nociceptive afferents [89,90], that results in changes to the neural activity of ascending spino-and trigeminothalamic tracts [91,92]. Interestingly, stimulation of the cerebral cortex can be either inhibitory, excitatory or both on spinothalamic neurons [91][92][93][94], and so it is not yet clear what neural mechanisms are involved in reducing pain.…”

“…The analgesic effect is, in part, mediated by presynaptic modulation of somatic afferents [85,[86][87][88], including nociceptive afferents [89,90], that results in changes to the neural activity of ascending spino-and trigeminothalamic tracts [91,92]. Interestingly, stimulation of the cerebral cortex can be either inhibitory, excitatory or both on spinothalamic neurons [91][92][93][94], and so it is not yet clear what neural mechanisms are involved in reducing pain. It is important to note that the most effective region for stimulation is the motor, rather than somatosensory, cortex and that stimulation does not appear to affect the sensory threshold or the discriminative component of pain.…”