The Mechanism of the Jaw Reflex Modulation during Swallowing

This study examined the acute effects of stretch tensions of kinesiology taping (KT) on the soleus (SOL), medial (MG), and lateral (LG) gastrocnemius Hoffmann-reflex (H-reflex) modulation in physically active healthy adults. A cross-over within-subject design was used in this study. Twelve physically active collegiate students voluntarily participated in the study (age = 21.3 ± 1.2 years; height = 175.6 ± 7.1 cm; body weight = 69.9 ± 7.1 kg). A standard Y-shape of KT technique was applied to the calf muscles. The KT was controlled in three tension intensities in a randomised order: paper-off, 50%, and 100% of maximal stretch tension of the tape. The peak-to-peak amplitude of maximal M-wave (Mmax) and H-reflex (Hmax) responses in the SOL, MG, and LG muscles were assessed before taping (pre-taping), taping, and after taping (post-taping) phases in the lying prone position. The results demonstrated significantly larger LG Hmax responses in the pre-taping condition than those in the post-taping condition during paper-off KT (p = 0.002). Moreover, the ΔHmax/Mmax of pre- and post-taping in the SOL muscle was significantly larger during 50%KT tension than that of paper-off (p = 0.046). In conclusion, the stretch tension of KT contributes minor influence on the spinal motoneuron excitability in the triceps surae during rest.

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No consistent startle modulation by reward

Scientific Reports ◽

10.1038/s41598-021-82902-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Iris Schutte ◽

Johanna M. P. Baas ◽

Ivo Heitland ◽

J. Leon Kenemans

Keyword(s):

Startle Reflex ◽

Task Engagement ◽

Future Experiment ◽

Reflex Modulation ◽

Monetary Rewards ◽

Potential Gain ◽

Subjective Value ◽

Experimental Parameters ◽

Startle Modulation ◽

Aversive Motivation

AbstractPrevious studies have not clearly demonstrated whether motivational tendencies during reward feedback are mainly characterized by appetitive responses to a gain or mainly by aversive consequences of reward omission. In the current study this issue was addressed employing a passive head or tails game and using the startle reflex as an index of the appetitive-aversive continuum. A second aim of the current study was to use startle-reflex modulation as a means to compare the subjective value of monetary rewards of varying magnitude. Startle responses after receiving feedback that a potential reward was won or not won were compared with a baseline condition without a potential gain. Furthermore, startle responses during anticipation of no versus potential gain were compared. Consistent with previous studies, startle-reflex magnitudes were significantly potentiated when participants anticipated a reward compared to no reward, which may reflect anticipatory arousal. Specifically for the largest reward (20-cents) startle magnitudes were potentiated when a reward was at stake but not won, compared to a neutral baseline without potential gain. In contrast, startle was not inhibited relative to baseline when a reward was won. This suggests that startle modulation during feedback is better characterized in terms of potentiation when missing out on reward rather than in terms of inhibition as a result of winning. However, neither of these effects were replicated in a more targeted second experiment. The discrepancy between these experiments may be due to differences in motivation to obtain rewards or differences in task engagement. From these experiments it may be concluded that the nature of the processing of reward feedback and reward cues is very sensitive to experimental parameters and settings. These studies show how apparently modest changes in these parameters and settings may lead to quite different modulations of appetitive/aversive motivation. A future experiment may shed more light on the question whether startle-reflex modulation after feedback is indeed mainly characterized by the aversive consequences of reward omission for relatively large rewards.

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Carotid Chemoreceptor Reflex Modulation by Arginine-Vasopressin Microinjected into the Nucleus Tractus Solitarius in Rats

Archives of Medical Research ◽

10.1016/j.arcmed.2006.03.001 ◽

2006 ◽

Vol 37 (6) ◽

pp. 709-716 ◽

Cited By ~ 1

Author(s):

Sergio Adrián Montero ◽

Alexander Yarkov ◽

Mónica Lemus ◽

Elena Roces de Álvarez-Buylla ◽

Ramón Álvarez-Buylla

Keyword(s):

Arginine Vasopressin ◽

Nucleus Tractus Solitarius ◽

Reflex Modulation

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Reflex Modulation of Heart Rate on Closure and Opening of an A-V Fistula.,

Experimental Biology and Medicine ◽

10.3181/00379727-71-17079 ◽

1949 ◽

Vol 71 (1) ◽

pp. 60-63 ◽

Cited By ~ 2

Author(s):

I. Jahan

Keyword(s):

Heart Rate ◽

Reflex Modulation

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Progressive Adaptation of the Soleus H-Reflex With Daily Training at Walking Backward

Journal of Neurophysiology ◽

10.1152/jn.00403.2002 ◽

2003 ◽

Vol 89 (2) ◽

pp. 648-656 ◽

Cited By ~ 52

Author(s):

Cyril Schneider ◽

Charles Capaday

Keyword(s):

Motor Program ◽

High Amplitude ◽

H Reflex ◽

Adaptive Plasticity ◽

Reflex Activity ◽

Reflex Modulation ◽

Surprising Result ◽

Backward Walking ◽

Rehabilitation Programs ◽

Daily Training

When untrained subjects walk backward on a treadmill the amplitude of the soleus H-reflex in midswing is equal to or exceeds the value in stance. This is a surprising result because during the swing phase of backward walking the soleus is inactive and its antagonist, the tibialis anterior, is active. We suggested that the high amplitude of the soleus H-reflex in late swing reflects task uncertainties, such as estimating the moment of foot contact with the ground and losing balance. In support of this idea we show that when untrained subjects held on to handrails the unexpected high-amplitude H-reflex during midswing was no longer present. We therefore asked whether daily training at this task without grasping the handrails would adaptively modify the H-reflex modulation pattern. In this event, within 10 days of training for 15 min daily, the anticipatory reflex activity at the beginning of training was gradually abated as the subjects reported gaining confidence at the task. However, when adapted subjects were made to walk backward with their eyes shut, the anticipatory reflex activity in midswing returned immediately. The reflex changes as a result of training were not due to changes in the motor activity or kinematics; they are likely part of the motor program controlling backward walking. This adaptive phenomenon may prove to be a useful model for studying the neural mechanisms of motor learning and adaptive plasticity in humans and may be relevant to rehabilitation programs for neurological patients.

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