Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Proprioception”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,063 records · Page 59Linked to original sources
PubMedDate not supplied

[Effect of vaccinal strain 17D of the yellow fever virus on the nature of proprioceptive information processing in the course of training BALB/c strain mice].

The influence of asymptomatic neuroviral infection produced by the 17D vaccine strain of yellow fever virus on the conditional reflex development of intracerebrally inoculated BALB/c mice was studied. In the virus-infected animals, the development of a conditional reflex in the labyrinth was hampered, on the one hand, by weakening of the inhibition process in the brain due to viral infection which was manifested by regular reproduction of "excess" information and perseverance; on the other hand, the development of the conditional reflex was made difficult because of the disturbance of the mechanisms providing for prolonged permanent level of awakeness. The observed changes were not accompanied by marked pathomorphological lesions in the CNS.

Animals↗
PubMed1995

Proprioceptive sensory neurons of a locust leg receive rhythmic presynpatic inhibition during walking.

Mechanosensory neurons from a proprioceptor (the femoral chordotonal organ) signal the movements and positions of the femorotibial joint of a locust leg. Intracellular recordings from these neurons during walking show that their spikes are superimposed on a depolarizing synaptic input generated near their output terminals in the CNS. The depolarization consists of a rhythmic synaptic input at each step, and a sustained input that begins before walking commences. In different sensory neurons, which signal particular features of the movement, the rhythmic depolarization occurs at distinct times during either the swing or stance phases of the step cycle. The depolarizing input is timed to coincide with the greatest spike response of a sensory neuron. The input is associated with a conductance change, appears to reverse just above resting potential, and thus has similar properties to the presynaptic inhibition in these same neurons during imposed joint movements (Burrows and Laurent, 1993; Burrows and Matheson, 1994). Three sources could contribute to these inputs: (1) interactions between sensory neurons of the same receptor signaling the same movement, (2) signals from different receptors in the same leg and other legs, and (3) outputs of central neurons involved in generating walking. When the leg, whose movements the sensory neurons signal is removed, both the sustained and rhythmic synaptic inputs persist. Sensory neurons in isolated ganglia treated with pilocarpine are also depolarized in phase with a rhythmic pattern expressed in leg motor neurons, indicating that central neurons must contribute. The maintained synaptic input to the terminals means that the overall effectiveness of the sensory spikes in evoking EPSPs in postsynaptic neurons will be reduced during walking, and the rhythmic component means that the spikes from particular sensory neurons will be further reduced at particular phases of the step cycle that they signal best.

Animals↗
PubMed1995

Responses of neurons in the central cervical nucleus of the rat to proprioceptive and vestibular inputs.

Activity of neurons in the central cervical nucleus (CCN) was recorded extracellularly in decerebrate, immobilized rats. Neurons were identified by their antidromic response to electrical stimulation of the contralateral superior cerebellar peduncle. Stimulation of the ipsilateral dorsal neck muscles (m. biventer cervicis and complexus [BCC]; m. splenius [S]) by a single electric pulse evoked a short-latency (approximately 1 ms) excitatory response in the majority of CCN neurons. The response was usually followed by a period of inhibition of the resting discharge (approximately 20 ms). Stimulation of the contralateral BCC or S usually produced only inhibition of the resting discharge (approximately 20 ms). Mechanical stretching of BCC or S resulted in activation (about 100% increased firing rate) of the ipsilateral CCN neurons, lasting for the duration of the stretch. A pronounced dynamic component, i.e. an extra-excitation at the beginning of the stretch and inhibition after termination of the stretch, was also observed. Stroking and pinching of the skin in the neck region affected the tested CCN neurons, while cutaneous stimuli at other sites of the body were inefficient. Stimulation of the vestibular receptors was performed in two ways. (i) Unilateral galvanic stimulation of the labyrinths by constant current pulses through the external acoustic meatus affected all CCN neurons tested. Contralateral stimulation with negative current was found to be most efficient; it produced excitation followed by inhibition. (ii) Natural vestibular stimulation was performed by rotating the animal in the transverse plane (roll, +/- 10 degrees) or the sagittal plane (pitch, +/- 5 degrees). Sinusoidal movements (0.5-1 Hz) or trapezoid movements were applied. Sinusoidal roll tilt evoked responses in all neurons tested, with a peak discharge during contralateral rolling or at the moment of transition from the ipsi- to contralateral position. All tested CCN neurons also responded statically to roll tilt, i.e. their tonic activity increased with up to 65%, of which the majority (80%) responded in the continuously maintained contralateral roll tilt position compared to the ipsilateral. Sinusoidal pitch tilt also affected all tested neurons, although the reaction was smaller than compared to roll. They usually responded by increasing their firing rate when moving towards the nose-down position. A static response (40-60% difference in the firing rate between the extreme pitch positions) was observed in some neurons. No tested neurons showed any clear rhythmic modulation during either spontaneous or induced, real or fictive locomotion.(ABSTRACT TRUNCATED AT 400 WORDS)

Afferent Pathways↗