ライフサイエンスコーパス: H-reflex

1 ove M-response threshold elicited the SOL(R) H-reflex.

2 l hip oscillations on the ipsilateral soleus H-reflex.

3 ost-alpha motoneuronal control of the soleus H-reflex.

4 electrophysiologically by the presence of an H-reflex.

5 included cortical electrical stimulation and H-reflexes.

6 ous procedures elicited the QD(R) and SOL(L) H-reflexes.

7 ensory CV, determined via Hoffmann's reflex (H-reflex) (A-fiber), was decreased in diabetic compared

8 ain is the slope of the relationship between H-reflex amplitude and EMG amplitude.

9 Agonist H reflex amplitudes were linearly related to, and increa

10 H-reflex amplitudes were higher than running H-reflex amplitudes by a constant amount.

11 At all levels of EMG, walking H-reflex amplitudes were higher than running H-reflex am

12 th the transition from silence to firing, so H reflex and other tests of 'excitability' must then be

13 ound between the amplitude of the antagonist H reflexes and the preceding antagonist IEMG.

14 The plasticity that changes the QD(R) H-reflex and locomotor kinematics may be inevitable (i.e

15 Electrophysiological recordings of the H-reflex and nonnociceptive flexion reflex were obtained

16 In addition, Hoffman reflex (H-reflex) and motor evoked potentials (MEPs) were record

17 ned increase or decrease in the right soleus H-reflex-and examined an old behavior-locomotion.

18 ributions to reciprocal inhibition of soleus H-reflexes are not static but rather are task-specific a

19 neal nerve, was assessed from changes in the H reflex at long conditioning intervals, in six normal s

20 ed by a paired-pulse TMS, and forearm flexor H reflexes before and after 750 pulses of 5 Hz rTMS over

21 dy asked whether operant conditioning of the H-reflex can modify locomotion in spinal cord-injured ra

22 normally prevents the plasticity underlying H-reflex change from impairing locomotion.

23 The final H-reflex change was the sum of within-session (i.e., tas

24 ans the development of operantly conditioned H-reflex change, a simple motor skill that develops grad

25 rrelated in direction and magnitude with the H-reflex change.

26 ributions to reciprocal inhibition of soleus H-reflexes changed with increasing levels of TA contract

27 An H reflex conditioning technique was used to monitor the

28 pinal dorsal ascending tract transection nor H-reflex conditioning alone impaired locomotion.

29 Using two separate methods (H-reflex conditioning and directional effects of TMS), w

30 Although H-reflex conditioning and locomotion did not interfere w

31 Thus, the acquisition of H-reflex conditioning consists of two phenomena, task-de

32 ocomotion did not interfere with each other, H-reflex conditioning did affect how locomotion was prod

33 Soleus H-reflex conditioning did not affect the duration, lengt

34 H-reflex conditioning is a model for studying the plasti

35 They also suggest that H-reflex conditioning might be used to improve the abnor

36 ation with other recent data, they show that H-reflex conditioning produces a complex pattern of spin

37 pinal dorsal ascending tract transection and H-reflex conditioning were combined, the rats developed

38 l rats the interactions of this new skill of H-reflex conditioning with the old well established skil

39 Over the 30 sessions, the soleus H-reflex decreased in two-thirds of the DC subjects (a s

40 Further, the soleus H-reflex depression did not vary with the contralateral

41 The lack of an H reflex despite normal motor nerve function in the hind

42 The SOL(L) H-reflex did not change.

43 The H-reflex did not decrease in the other DC subjects or in

44 n was assessed, subjects completed either 30 H-reflex down-conditioning sessions (DC subjects) or 30

45 antagonistic group I afferents on the soleus H-reflex during imposed sinusoidal hip movements.

46 The degree of depression of the second H-reflex during standing ( > 78%) was similar in magnitu

47 muli which had no effect on the amplitude of H reflexes elicited in active ADM muscle.

48 phase of walking as observed for the soleus H-reflex elicited by tibial nerve stimulation.

49 In rats in which the soleus H-reflex elicited in the conditioning protocol (i.e., th

50 had been decreased by down-conditioning, the H-reflexes elicited during the stance and swing phases o

51 After transection, the H-reflex exhibited decreased depression at high stimulat

52 To examine soleus H-reflex gain across a range of EMG levels during human

53 us system adjusts H-reflex threshold but not H-reflex gain between walking and running.

54 stretch reflex responses.A common measure of H-reflex gain is the slope of the relationship between H

55 We hypothesised that H-reflex gain would be independent of gravity level.We r

56 Similarly, in rats in which the conditioning H-reflex had been increased by up-conditioning, the loco

57 onditioning protocol (i.e., the conditioning H-reflex) had been decreased by down-conditioning, the H

58 There was no effect on H reflexes in the flexor carpi radialis muscle, even tho

59 peripheral nerves it is difficult to elicit H-reflex in leg muscles other than the soleus, especiall

60 rons from animals in which the triceps surae H-reflex in one leg had been increased (HRup mode) or de

61 d the impact of down-conditioning the soleus H-reflex in people with impaired locomotion caused by ch

62 Combined with the larger H-reflexes in TU rats, this anatomical finding supports

63 s as we observed an enhanced Hoffman reflex (H-reflex), indicating a hyperexcitable spinal cord.

64 The Hoffmann (H-) reflex is an electrical analogue of the monosynaptic

65 Studying H-reflex modulation provides insight into how the nervou

66 Results showed that the flexor, but not H-reflex, of Chronic Spinal rats was significantly large

67 d the effect of up-conditioning soleus (SOL) H-reflex on SOL and tibialis anterior (TA) function afte

68 A condition-test (C-T) H-reflex paradigm (conditioned stimulus applied to the c

69 ise be disturbed by the change in the SOL(R) H-reflex pathway.

70 stretch reflex or its electrical analog, the H-reflex, produces spinal cord plasticity and can thereb

71 The percent depression of the second H-reflex relative to the first was used as a measure of

72 al and pre-synaptic inhibition of the soleus H-reflex, respectively.

73 Over the 24 conditioning sessions, H-reflex size gradually increased in six of eight HRup s

74 After a baseline period in which soleus H-reflex size was measured and locomotion was assessed,

75 When the subject was asked to change H-reflex size, immediate visual feedback indicated wheth

76 ion in frequency-dependent depression of the H-reflex, suggesting hyperreflexia.

77 inhibition acting on the ipsilateral soleus H-reflex, supporting cross-leg reflex and heteronymous m

78 for 50 d to a protocol that rewarded SOL(R) H-reflexes that were above (HRup rats) or below (HRdown

79 nt conditioning of the primate triceps surae H-reflex, the electrical analog of the spinal stretch re

80 and monkeys gradually change the size of the H-reflex, the electrical analog of the spinal stretch re

81 The frequency-related depression of the Sol H reflex, thought to reflect HD, was tested at rest, bef

82 We conclude that the nervous system adjusts H-reflex threshold but not H-reflex gain between walking

83 9 +/- 2% (p < 0.001) and increased the QD(R) H-reflex to 121 +/- 7% (p = 0.02).

84 HRup conditioning increased the SOL(R) H-reflex to 214 +/- 37% (mean +/- SEM) of control (p = 0

85 HRdown conditioning decreased the SOL(R) H-reflex to 69 +/- 2% (p < 0.001) and increased the QD(R

86 f control (p = 0.02) and decreased the QD(R) H-reflex to 71 +/- 26% (p = 0.06).

87 normalised the stimulus M-wave and resulting H-reflex to the maximal M-wave amplitude (Mmax) elicited

88 ued control data collection (TC rats) or SOL H-reflex up-conditioning (TU rats).

89 H-reflex up-conditioning increased the right soleus burs

90 These results suggest that H-reflex up-conditioning may improve functional recovery

91 ere then either exposed or not exposed to an H-reflex up-conditioning protocol that greatly increased

92 cal finding supports the hypothesis that SOL H-reflex up-conditioning strengthened primary afferent r

93 ised, slopes of linear regressions fitted to H-reflex versus EMG data were independent of gravity for

94 The soleus H-reflex was also conditioned by medial gastrocnemius (M

95 The soleus H-reflex was conditioned by stimulating the common peron

96 hip was higher than the left; when the right H-reflex was decreased by conditioning, the opposite occ

97 The soleus H-reflex was evoked every 4 s during bilateral synchrono

98 When the right H-reflex was increased by conditioning, the right step l

99 In each conditioning session, the soleus H-reflex was measured while the subject was or was not a

100 owever, the conditioned change in the stance H-reflex was positively correlated with change in the am

101 The ipsilateral soleus H-reflex was profoundly depressed in all conditions.

102 than in TC rats, and the final recovered SOL H-reflex was significantly larger in TU than in TC rats.

103 ns (DC subjects) or 30 sessions in which the H-reflex was simply measured [unconditioned (UC) subject

104 In a separate set of experiments H reflexes were elicited in the wrist flexors instead of

105 Ipsilateral SA H reflexes were evoked at a latency of 9.9 +/- 0.8 ms (p

106 H reflexes were induced in the human quadriceps muscle b

107 Similar suppression of MEP and H-reflex were also seen.

108 increased by up-conditioning, the locomotor H-reflexes were also larger.

109 H-reflexes were also suppressed on these trials, indicat

110 At rest, the second H-reflexes were depressed an average of 73% relative to

111 Notably, left hand H-reflexes were not modulated on these trials, consisten

112 In the second experiment, paired H-reflexes were obtained from the S and medial (MG) and

113 During a terminal experiment, H-reflexes were recorded from interosseus muscles after

114 transcranial magnetic stimulation (TMS) and H-reflexes were recorded from left hand muscles during c

115 ng phases of locomotion (i.e., the locomotor H-reflexes) were also smaller.

116 s inferred from modifications in the size of H reflex, which are often more prominent after skilled m

117 Operant conditioning of the vertebrate H-reflex, which appears to be closely related to learnin

118 cles was measured by conditioning the soleus H-reflex with stimulation of the common peroneal nerve.