Crosstalk opposing view: Independent fusimotor control of muscle spindles in humans: there is little to gain

This article examines a number of issues relating to discussions of the origin of language and related topics among early Arabic linguists. A number of these discussions treated the topic of the ‘revelationist’ view of language (tawqīf), and the opposing view that language had developed as a result of human convention (iṣṭilāḥ). It has been suggested that religious doctrine hampered the development of the linguistic tradition, as theologically motivated views increasingly governed the way in which linguists were able to articulate their positions on this and related subjects. We contend that the evidence does not altogether support this view, and that there was a subtle interplay between theological views and linguistic theories. Individual linguists, whom tradition identifies as having certain theological tendencies, are found to have followed lines of linguistic thinking at odds with what is assumed to have been the religious doctrine to which they subscribed. An increasingly sophisticated tradition of scholarship refined and reassessed arguments based on the Qur'an and earlier thought, with a concern for the theological implications of issues such as ishtiqāq, tarāduf and addād.

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Essentially Evaluative?

10.1093/oso/9780198803430.003.0007 ◽

2017 ◽

Author(s):

Simon Kirchin

Keyword(s):

Opposing View ◽

Thick Concepts

This chapter continues the account of thick concepts defended in Chapter Six by arguing that such concepts are essentially evaluative. This is opposed to the view that thick concepts are merely nonevaluative concepts that happen, every so often, to convey evaluation through linguistic and other contingent conventions. This opposing view has been best articulated by Pekka Väyrynen. This chapter presents and considers Väyrynen’s arguments for his claim, and the assumptions that lie behind both his own account of thin and thick concepts, and his overall view of evaluation. This chapter ventures that his arguments against nonseparationism do not work and that, in addition, his own position is suspect.

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Analysis of activity of muscle spindles of the jaw-closing muscles during normal movements in the cat.

The Journal of Physiology ◽

10.1113/jphysiol.1975.sp011207 ◽

1975 ◽

Vol 253 (2) ◽

pp. 565-582 ◽

Cited By ~ 71

Author(s):

F W Cody ◽

L M Harrison ◽

A Taylor

Keyword(s):

Muscle Spindles

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The path from trigeminal asymmetry to cognitive impairment: a behavioral and molecular study

Scientific Reports ◽

10.1038/s41598-021-82265-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maria Paola Tramonti Fantozzi ◽

Giulia Lazzarini ◽

Vincenzo De Cicco ◽

Angela Briganti ◽

Serena Argento ◽

...

Keyword(s):

Pupil Size ◽

Muscle Spindles ◽

Molecular Study ◽

Contralateral Side ◽

Acute Effects ◽

Adult Rats ◽

Afferent Inputs ◽

Acute And Chronic Effects ◽

The Brain ◽

Mandibular Branch

AbstractTrigeminal input exerts acute and chronic effects on the brain, modulating cognitive functions. Here, new data from humans and animals suggest that these effects are caused by trigeminal influences on the Locus Coeruleus (LC). In humans subjects clenching with masseter asymmetric activity, occlusal correction improved cognition, alongside with reductions in pupil size and anisocoria, proxies of LC activity and asymmetry, respectively. Notably, reductions in pupil size at rest on the hypertonic side predicted cognitive improvements. In adult rats, a distal unilateral section of the trigeminal mandibular branch reduced, on the contralateral side, the expression of c-Fos (brainstem) and BDNF (brainstem, hippocampus, frontal cortex). This counterintuitive finding can be explained by the following model: teeth contact perception loss on the lesioned side results in an increased occlusal effort, which enhances afferent inputs from muscle spindles and posterior periodontal receptors, spared by the distal lesion. Such effort leads to a reduced engagement of the intact side, with a corresponding reduction in the afferent inputs to the LC and in c-Fos and BDNF gene expression. In conclusion, acute effects of malocclusion on performance seem mediated by the LC, which could also contribute to the chronic trophic dysfunction induced by loss of trigeminal input.

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Computer Simulation of the Responses of Human Motoneurons to Composite 1A EPSPS: Effects of Background Firing Rate

Journal of Neurophysiology ◽

10.1152/jn.1997.77.1.405 ◽

1997 ◽

Vol 77 (1) ◽

pp. 405-420 ◽

Cited By ~ 36

Author(s):

Kelvin E. Jones ◽

Parveen Bawa

Keyword(s):

Computer Simulation ◽

Firing Rate ◽

Time Course ◽

Current Model ◽

Response Probability ◽

Muscle Spindles ◽

Excitatory Postsynaptic Potential ◽

Biophysical Properties ◽

Rhythmic Firing ◽

The Relationship

Jones, Kelvin E. and Parveen Bawa. Computer simulation of the responses of human motoneurons to composite 1A EPSPS: effects of background firing rate. J. Neurophysiol. 77: 405–420, 1997. Two compartmental models of spinal alpha motoneurons were constructed to explore the relationship between background firing rate and response to an excitatory input. The results of these simulations were compared with previous results obtained from human motoneurons and discussed in relation to the current model for repetitively firing human motoneurons. The morphologies and cable parameters of the models were based on two type-identified cat motoneurons previously reported in the literature. Each model included five voltage-dependent channels that were modeled using Hodgkin-Huxley formalism. These included fast Na+ and K+ channels in the initial segment and fast Na+ and K+ channels as well as a slow K+ channel in the soma compartment. The density and rate factors for the slow K+ channel were varied until the models could reproduce single spike AHP parameters for type-identified motoneurons in the cat. Excitatory synaptic conductances were distributed along the equivalent dendrites with the same density described for la synapses from muscle spindles to type-identified cat motoneurons. Simultaneous activation of all synapses on the dendrite resulted in a large compound excitatory postsynaptic potential (EPSP). Brief depolarizing pulses injected into a compartment of the equivalent dendrite resulted in pulse potentials (PPs), which resembled the compound EPSPs. The effects of compound EPSPs and PPs on firing probability of the two motoneuron models were examined during rhythmic firing. Peristimulus time histograms, constructed between the stimulus and the spikes of the model motoneuron, showed excitatory peaks whose integrated time course approximated the time course of the underlying EPSP or PP as has been shown in cat motoneurons. The excitatory peaks were quantified in terms of response probability, and the relationship between background firing rate and response probability was explored. As in real human motoneurons, the models exhibited an inverse relationship between response probability and background firing rate. The biophysical properties responsible for the relationship between response probability and firing rate included the shapes of the membrane voltage trajectories between spikes and nonlinear changes in PP amplitude during the interspike interval at different firing rates. The results from these simulations suggest that the relationship between response probability and background firing rate is an intrinsic feature of motoneurons. The similarity of the results from the models, which were based on the properties of cat motoneurons, and those from human motoneurons suggests that the biophysical properties governing rhythmic firing in human motoneurons are similar to those of the cat.

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