Proprioceptive afferents differentially contribute to effortful perception of object heaviness and length

The position of the coxal segment of the locust hind leg relative to the thorax is monitored by a variety of proprioceptors, including three chordotonal organs and a myochordotonal organ. The sensory neurons of two of these proprioceptors, the posterior joint chordotonal organ (pjCO) and the myochordotonal organ (MCO), have axons in the purely sensory metathoracic nerve 2C (N2C). The connections made by these afferents with metathoracic motor neurons innervating thoraco-coxal and wing muscles were investigated by electrical stimulation of N2C and by matching postsynaptic potentials in motor neurons with afferent spikes in N2C. Stretch applied to the anterior rotator muscle of the coxa (M121), with which the MCO is associated, evoked sensory spikes in N2C. Some of the MCO afferent neurons make direct excitatory chemical synaptic connections with motor neurons innervating the thoraco-coxal muscles M121, M126 and M125. Parallel polysynaptic pathways via unidentified interneurons also exist between MCO afferents and these motor neurons. Connections with the common inhibitor 1 neuron and motor neurons innervating the thoraco-coxal muscles M123/4 and wing muscles M113 and M127 are polysynaptic. Afferents of the pjCO also make polysynaptic connections with motor neurons innervating thoraco-coxal and wing muscles, but no evidence for monosynaptic pathways was found.

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Central distribution of masticatory and lingual proprioceptive afferents relative to jaw and tongue movements. Part I. Masticatory proprioceptive afferents of the mouse.

THE JOURNAL OF THE STOMATOLOGICAL SOCIETY JAPAN ◽

10.5357/koubyou.54.365 ◽

1987 ◽

Vol 54 (2) ◽

pp. 365-386

Author(s):

Noriyuki Narita

Keyword(s):

Tongue Movements ◽

Proprioceptive Afferents

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Effect of upper airway negative pressure on proprioceptive afferents from the tongue

Journal of Applied Physiology ◽

10.1152/jappl.1999.86.4.1396 ◽

1999 ◽

Vol 86 (4) ◽

pp. 1396-1401 ◽

Cited By ~ 7

Author(s):

A. Brancatisano ◽

P. Davis ◽

T. van der Touw ◽

J. R. Wheatley

Keyword(s):

Hypoglossal Nerve ◽

Upper Airway ◽

Rapid Onset ◽

Firing Frequency ◽

Tongue Muscle ◽

Airway Mucosa ◽

Afferent Fibers ◽

Before And After ◽

Proprioceptive Afferents ◽

Passive Stretch

We examined whether receptors in the tongue muscle respond to negative upper airway pressure (NUAP). In six cats, one hypoglossal nerve was cut and its distal end was prepared for single-fiber recording. Twelve afferent fibers were selected for study on the basis of their sensitivity to passive stretch (PS) of the tongue. Fiber discharge frequency was measured during PS of the tongue and after the rapid onset of constant NUAP. During PS of 1–3 cm, firing frequency increased from 17 ± 7 to 40 ± 11 (SE) Hz ( P < 0.01). In addition, 8 of the 12 fibers responded to NUAP (−10 to −30 cmH2O), with firing frequency increasing from 23 ± 9 to 41 ± 9 Hz ( P < 0.001). In two fibers tested, the increase in firing frequency in response to NUAP was not altered by topical anesthesia (10% lignocaine) applied liberally to the entire upper airway mucosa. Our results demonstrate that afferent discharges from the hypoglossal nerve are elicited by 1) stretching of the tongue and 2) NUAP before and after upper airway anesthesia. We speculate that activation of proprioceptive mechanoreceptors in the cat’s tongue provides an additional pathway for the reflex activation of upper airway dilator muscles in response to NUAP, independent of superficially located mucosal mechanoreceptors.

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Synaptic potentials in the central terminals of locust proprioceptive afferents generated by other afferents from the same sense organ

Journal of Neuroscience ◽

10.1523/jneurosci.13-02-00808.1993 ◽

1993 ◽

Vol 13 (2) ◽

pp. 808-819 ◽

Cited By ~ 45

Author(s):

M Burrows ◽

G Laurent

Keyword(s):

Sense Organ ◽

Synaptic Potentials ◽

Proprioceptive Afferents

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Expiratory threshold load under extracorporeal circulation: effects of vagal afferents

Journal of Applied Physiology ◽

10.1152/jappl.1983.55.2.307 ◽

1983 ◽

Vol 55 (2) ◽

pp. 307-315 ◽

Cited By ~ 4

Author(s):

Y. Jammes ◽

P. T. Bye ◽

R. L. Pardy ◽

C. Katsardis ◽

S. Esau ◽

...

Keyword(s):

Mechanical Vibration ◽

Muscle Spindles ◽

Vagal Afferents ◽

Abdominal Muscles ◽

Vagus Nerves ◽

Linea Alba ◽

Arterial Blood Gas ◽

Arterial Blood ◽

Anesthetized Dogs ◽

Proprioceptive Afferents

Nine anesthetized dogs breathed against an expiratory threshold load (ETL) applied by switching the expiratory circuit into a column of H2O to a depth of 20-30 cm. Arterial blood gas tensions were maintained in the normal range by placing the dogs under arteriovenous bypass to avoid any uncontrolled chemostimulation. There was an increase in integrated electromyogram activity of the diaphragm with the ETL. This was rarely observed after cold block of the vagus nerves which also reduced the evoked expiratory activity. The ventilatory response to hypercapnia was greatly depressed under loaded breathing whether vagal afferents were intact or blocked by cold. Both inspiratory drive and ventilatory timing were affected, suggesting that the central integration of chemosensitive afferents was altered. Proof of supraspinal projections of proprioceptive inputs from abdominal muscles was provided by the demonstration of changes in ventilatory timing during selective activation of muscle spindles in abdominal muscles by high-frequency mechanical vibration applied to the linea alba. Thus these observations suggest that during ETL breathing, a possible interaction exists between chemoreflex drive and proprioceptive afferents.

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Basal and evoked levels of bioassayable growth hormone are altered by hindlimb unloading

Journal of Applied Physiology ◽

10.1152/japplphysiol.00615.2005 ◽

2006 ◽

Vol 100 (3) ◽

pp. 1037-1042 ◽

Cited By ~ 10

Author(s):

A. J. Bigbee ◽

R. E. Grindeland ◽

R. R. Roy ◽

H. Zhong ◽

K. L. Gosselink ◽

...

Keyword(s):

Growth Hormone ◽

Fiber Type ◽

Plasma Corticosterone ◽

Hindlimb Unloading ◽

Male Rats ◽

Afferent Fibers ◽

Basal Plasma ◽

Proprioceptive Afferents ◽

Acute Changes

Bioassayable growth hormone (BGH) in rats is released in large quantities from the pituitary in response to the activation of large, proprioceptive afferent fibers from fast and mixed fiber-type hindlimb musculature. We hypothesized that hindlimb unloading (HU) of adult male rats would 1) reduce the basal levels of plasma BGH, and 2) abolish stimulus-induced BGH release. Rats were exposed to HU for 1, 4, or 8 wk. Plasma and pituitaries were collected under isoflurane anesthesia for hormone analyses. Additionally, at 4 and 8 wk, a subset of rats underwent an in situ electrical stimulation (Stim) of tibial nerve proprioceptive afferents. Basal plasma BGH levels were significantly reduced (−51 and −23%) after 1 and 8 wk of HU compared with ambulatory controls (Amb). Although Amb-Stim rats exhibited increased plasma BGH levels (88 and 143%) and decreased pituitary BGH levels (−27 and −22%) at 4 and 8 wk, respectively, stimulation in HU rats had the opposite effect, reducing plasma BGH (−25 and −33%) and increasing pituitary BGH levels (47 and 10%) relative to HU alone at 4 and 8 wk. The 22-kDa form of GH measured by immunoassay and the plasma corticosterone, T3, T4, and testosterone levels were unchanged by HU or Stim at all time points. These data suggest that BGH synthesis and release from the pituitary are sensitive both to chronically reduced neuromuscular loading and to acute changes in neuromuscular activation, independent of changes in other circulating hormones. Thus BGH may play a role in muscle, bone, and metabolic adaptations that occur in response to chronically unloaded states.

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A New System to Objectively Measure Ankle Proprioception

2020 Design of Medical Devices Conference ◽

10.1115/dmd2020-9094 ◽

2020 ◽

Author(s):

Arash Mahnan ◽

Jessica Holst-Wolf ◽

Jürgen Konczak

Keyword(s):

Ankle Joint ◽

Healthy Adult ◽

Psychometric Testing ◽

Just Noticeable Difference ◽

Testing Protocol ◽

Adult Participants ◽

Human Ankle ◽

Proprioceptive Afferents ◽

Ankle Proprioception ◽

New System

Abstract Proprioceptive afferents from the ankle joint are essential feedback for maintaining balance. However, there is no widely accepted test or measurement system available for determining the proprioceptive accuracy of the human ankle joint. Here, we present a system with a novel hardware design that applies an established psychometric testing protocol that generates a Just-Noticeable-Difference (JND) threshold as a measure of ankle proprioceptive acuity at the end of testing. To establish the system validity, twelve healthy adult participants completed the assessment. Testing required 25 trials and took approximately 10 minutes to complete. We show exemplar data of the ankle JND threshold and the summary results for all twelve participants. This assessment has the potential to become a tool for clinicians to identify proprioceptive impairment at the ankle and to assess the efficacy of sensorimotor interventions for improving balance in clinical populations.

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