Short-term habituation of equine limb kinematics to tactile stimulation of the coronet

2008 ◽  
Vol 21 (03) ◽  
pp. 211-214 ◽  
Author(s):  
A. White ◽  
L. Kaiser ◽  
S. Nauwelaerts ◽  
M. Lavagnino ◽  
N. C. Stubbs ◽  
...  

SummaryA lightweight bracelet that provides tactile stimulation to the horse’s pastern and coronet induces a higher flight arc of the hoof. This study addresses the pattern of habituation to these devices. Objective: To evaluate short-term habituation to tactile stimulation of the pastern and coronet in trotting horses. Methods: Tactile stimulation was provided by a lightweight (55 g) device consisting of a strap with seven chains that was attached loosely around the pastern. Reflective markers were fixed to the dorsal hoof wall, the forehead and over the tenth thoracic vertebra of eight sound horses. The horses trotted in hand 10 times at a consistent velocity along a 30 m runway under three conditions applied in random order at two-hour intervals: no stimulators, stimulators on both front hooves or stimulators on both hind hooves. One stride per trial was analyzed to determine peak hoof heights in the swing phase. Sequential trials with stimulators were compared with unstimulated trials using a nested ANCOVA and Bonferronni’s post hoc test (P<0.005). Results: Peak hind hoof height increased significantly for all 10 trials when wearing hind stimulators, whereas peak fore hoof height increased during the first six trials only when wearing fore stimulators. The first trial with stimulators showed the greatest elevation, followed by a rapid decrease over the next three trials and then a more gradual decrease. Conclusions: If the goal is to facilitate a generalized muscular response, a short burst of tactile stimulation is likely to be most effective, whereas longer periods of stimulation will be more effective for strength training.

1993 ◽  
Vol 69 (2) ◽  
pp. 522-532 ◽  
Author(s):  
Y. I. Arshavsky ◽  
T. G. Deliagina ◽  
G. N. Gamkrelidze ◽  
G. N. Orlovsky ◽  
Y. V. Panchin ◽  
...  

1. A contact of the pteropod mollusk Clione limacina with its prey (small pteropod mollusk Limacina helicina) evokes a complex pattern of hunting and feeding behavior: protraction of tentacles to seize the prey, activation of buccal apparatus to swallow the prey, activation of locomotor system (speeding up of wing beating), reversal of reaction to tactile stimulation of the head, loss of normal (vertical) orientation in space, and swimming in circles. After injection of physostigmine (PhS), the acetylcholinesterase inhibitor, into the hemocoel of intact Clione, all these manifestations of the hunting and feeding behavior could be evoked by tactile stimulation of the head, or they arose spontaneously. 2. In the preparation of the isolated CNS, the effect of PhS on the neural networks controlling different aspects of the hunting and feeding behavior was studied by recording from neurons monitoring activity of different networks (< or = 4 neurons simultaneously). Tactile stimulation of the head was mimicked by a short-term electrical stimulation of the corresponding nerve. Before PhS application, the nerve stimulation evoked elements of the defense reaction, i.e., long-lasting inhibition of all main motor control systems: the locomotor network in the pedal ganglia, the tentacle control network in the cerebral ganglia, and the network controlling radula and hook movements in the buccal ganglia. However, after PhS application, the same stimulus evoked a long-lasting bout of excitation in all the three networks accompanied by activation of the heart-exciting neuron as well as by a modification of the activity of statocyst receptor cells controlling Clione's spatial orientation (the "fictive hunting bout"). Similar hunting bouts could arise spontaneously. 3. Injection of acetylcholine (ACh) into the hemocoel of intact Clione was less effective than injection of PhS. After ACh injection, reversal of reaction to head stimulation was observed in < or = 20% of the experiments (the percentage of positive results was higher if ACh was injected into the head just over the CNS). Bath application of ACh to the isolated CNS did not produce the hunting bouts. However, a short-term local application of ACh to the cerebral ganglia in the isolated CNS resulted in activation of the main motor systems controlling locomotion, protraction of tentacles, and movements of buccal mass. 4. During spontaneous PhS-induced bouts, excitation of different networks involved in hunting behavior was sometimes not quite synchronous. Different networks could be excited in variable order over a period of up to several seconds.(ABSTRACT TRUNCATED AT 400 WORDS)


2019 ◽  
Vol 28 (3) ◽  
pp. 1039-1052
Author(s):  
Reva M. Zimmerman ◽  
JoAnn P. Silkes ◽  
Diane L. Kendall ◽  
Irene Minkina

Purpose A significant relationship between verbal short-term memory (STM) and language performance in people with aphasia has been found across studies. However, very few studies have examined the predictive value of verbal STM in treatment outcomes. This study aims to determine if verbal STM can be used as a predictor of treatment success. Method Retrospective data from 25 people with aphasia in a larger randomized controlled trial of phonomotor treatment were analyzed. Digit and word spans from immediately pretreatment were run in multiple linear regression models to determine whether they predict magnitude of change from pre- to posttreatment and follow-up naming accuracy. Pretreatment, immediately posttreatment, and 3 months posttreatment digit and word span scores were compared to determine if they changed following a novel treatment approach. Results Verbal STM, as measured by digit and word spans, did not predict magnitude of change in naming accuracy from pre- to posttreatment nor from pretreatment to 3 months posttreatment. Furthermore, digit and word spans did not change from pre- to posttreatment or from pretreatment to 3 months posttreatment in the overall analysis. A post hoc analysis revealed that only the less impaired group showed significant changes in word span scores from pretreatment to 3 months posttreatment. Discussion The results suggest that digit and word spans do not predict treatment gains. In a less severe subsample of participants, digit and word span scores can change following phonomotor treatment; however, the overall results suggest that span scores may not change significantly. The implications of these findings are discussed within the broader purview of theoretical and empirical associations between aphasic language and verbal STM processing.


2020 ◽  
pp. 121-134
Author(s):  
S. A. Andryushin

In 2019, a textbook “Macroeconomics” was published in London, on the pages of which the authors presented a new monetary doctrine — Modern Monetary Theory, MMT, — an unorthodox concept based on the postulates of Post-Keynesianism, New Institutionalism, and the theory of Marxism. The attitude to this scientific concept in the scientific community is ambiguous. A smaller part of scientists actively support this doctrine, which is directly related to state monetary and fiscal stimulation of full employment, public debt servicing and economic growth. Others, the majority of economists, on the contrary, strongly criticize MMT, arguing that the new theory hides simple left-wing populism, designed for a temporary and short-term effect. This article considers the origins and the main provisions of MMT, its discussions with the mainstream, criticism of the basic tenets of MMT, and also assesses possible prospects for the development of MMT in the medium term.


1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.


2021 ◽  
pp. 1-10
Author(s):  
Michihiro Osumi ◽  
Daisuke Shimizu ◽  
Yuki Nishi ◽  
Shu Morioka

Background: Patients with brachial plexus avulsion (BPA) usually experience phantom sensations and phantom limb pain (PLP) in the deafferented limb. It has been suggested that evoking the sensation of touch in the deafferented limb by stimulating referred sensation areas (RSAs) on the cheek or shoulder might alleviate PLP. However, feasible rehabilitation techniques using this approach have not been reported. Objective: The present study sought to examine the analgesic effects of simple electrical stimulation of RSAs in BPA patients with PLP. Methods: Study 1: Electrical stimulation of RSAs for 60 minutes was conducted for six BPA patients suffering from PLP to examine short-term analgesic effects. Study 2: A single case design experiment was conducted with two BPA patients to investigate whether electrical stimulation of RSAs was more effective for alleviating PLP than control electrical stimulation (electrical stimulation of sites on side opposite to the RSAs), and to elucidate the long-term effects of electrical stimulation of RSAs. Results: Study 1: Electrical stimulation of RSAs evoked phantom touch sensations in the deafferented limb, and significantly alleviated PLP (p <  0.05). Study 2: PLP was alleviated more after electrical stimulation on RSAs compared with control electrical stimulation (p <  0.05). However, the analgesic effects of electrical stimulation on RSAs were observed only in the short term, not in the long term (p >  0.05). Conclusions: Electrical stimulation of RSAs not only evoked phantom touch sensation but also alleviated PLP in the short term. The results indicate that electrical stimulation of RSAs may provide a useful practical rehabilitation technique for PLP. Future studies will be required to clarify the mechanisms underlying immediate PLP alleviation via electrical stimulation of RSAs.


1982 ◽  
Vol 47 (5) ◽  
pp. 885-908 ◽  
Author(s):  
R. Gillette ◽  
M. P. Kovac ◽  
W. J. Davis

1. A population of interneurons that control feeding behavior in the mollusk Pleurobranchaea has been analyzed by dye injection and intracellular stimulation/recording in whole animals and reduced preparations. The population consists of 12-16 somata distributed in two bilaterally symmetrical groups on the anterior edge of the cerebropleural ganglion (brain). On the basis of their position adjacent to the cerebral lobes, these cells have been named paracerebral neurons (PCNs). This study concerns pme subset pf [MCs. the large, phasic ones, which have the strongest effect on the feeding rhythm (21). 2. Each PCN sends a descending axon via the ipsilateral cerebrobuccal connective to the buccal ganglion. Axon branches have not been detected in other brain or buccal nerves and hence the PCNs appear to be interneurons. 3. In whole-animal preparations, tonic intracellular depolarization of the PNCs causes them to discharge cyclic bursts of action potentials interrupted by a characteristic hyperpolarization. In all specimens that exhibit feeding behavior, the interburst hyperpolarization is invariably accompanied by radula closure and the beginning of proboscis retraction (the "bite"). No other behavorial effect of PCN stimulation has been observed. 4. In whole-animal preparations, the PCNs are excited by food and tactile stimulation of the oral veil, rhinophores, and tentacles. When such stimuli induce feeding the PCNs discharge in the same bursting pattern seen during tonic PCN depolarization, with the cyclic interburst hyperpolarization phase locked to the bit. When specimens egest an unpalatable object by cyclic buccal movements, however, the PCNs are silent. The PCNs therefore exhibit properties expected of behaviorally specific "command" neurons for feeding. 5. Silencing one or two PCNs by hyperpolarization may weaken but does not prevent feeding induced by natural food stimuli. Single PCNs therefore can be sufficient but are not necessary to induction of feeding behavior. Instead the PCNs presumably operate as a population to control feeding. 6. In isolated nervous system preparations tonic extracellular stimulation of the stomatogastric nerve of the buccal ganglion elicits a cyclic motor rhythm that is similar in general features to the PNC-induced motor rhythm. Bursts of PCN action potentials intercalated at the normal phase position in this cycle intensify the buccal rhythm. Bursts of PCN impulses intercalated at abnormal phase positions reset the buccal rhythm. The PCNs, therefore, also exhibit properties expected of pattern-generator elements and/or coordinating neurons for the buccal rhythm. 7. The PCNs are recruited into activity when the buccal motor rhythm is elicited by stomatogastric nerve stimulation or stimulation of the reidentifiable ventral white cell. The functional synergy between the PCNs and the buccal rhythm is therefore reciprocal. 8...


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