Abstract:
:Few studies have analyzed activity-induced changes in EMG activity in individual human motor units. We studied the changes in human thenar motor unit EMG that accompany the potentiation of twitch force and fatigue of tetanic force. Single motor unit EMG and force were recorded in healthy subjects in response to selective stimulation of their motor axons within the median nerve just above the elbow. Twitches were recorded before and after a series of pulse trains delivered at frequencies that varied between 5 and 100 Hz. This stimulation induced significant increases in EMG amplitude, duration, and area. However, in relative terms, all of these EMG changes were substantially smaller than the potentiation of twitch force. Another 2 min of stimulation (13 pulses at 40 Hz each second) induced additional potentiation of EMG amplitude, duration, and area, but the tetanic force from every unit declined. Thus activity-induced changes in human thenar motor unit EMG do not indicate the alterations in force or vice versa. These data suggest that different processes underlie the changes in EMG and force that occur during human thenar motor unit activity.
journal_name
J Neurophysioljournal_title
Journal of neurophysiologyauthors
Thomas CK,Johansson RS,Bigland-Ritchie Bdoi
10.1152/jn.00924.2005subject
Has Abstractpub_date
2006-03-01 00:00:00pages
1518-26issue
3eissn
0022-3077issn
1522-1598pii
00924.2005journal_volume
95pub_type
临床试验,杂志文章abstract::We examined the influence of focal cerebellar lesions on working memory (n-back task), gait, and the interaction between working memory and different gait tasks in a dual-task paradigm. The analysis included 17 young patients with chronic focal lesions after cerebellar tumor resection and 17 age-matched controls. Pati...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00062.2013
更新日期:2013-11-01 00:00:00
abstract::In free viewing, the eyes return to previously visited locations rather frequently, even though the attentional and memory-related processes controlling eye-movement show a strong antirefixation bias. To overcome this bias, a special refixation triggering mechanism may have to be recruited. We probed the neural eviden...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00121.2018
更新日期:2018-11-01 00:00:00
abstract::Early visual motion signals are local and one-dimensional (1-D). For specification of global two-dimensional (2-D) motion vectors, the visual system should appropriately integrate these signals across orientation and space. Previous neurophysiological studies have suggested that this integration process consists of tw...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00821.2011
更新日期:2012-06-01 00:00:00
abstract::The contributions of the hyperpolarization-activated current, I(h), to generation of rhythmic activities are well described for various central neurons, particularly in thalamocortical circuits. In the present study, we investigated effects of a general anesthetic, propofol, on native I(h) in neurons of thalamus and c...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00389.2005
更新日期:2005-12-01 00:00:00
abstract::1. We studied the effect of electrical stimulation of the peribrachial region (PBR) in the brain stem on the visual response of single cells in the dorsal lateral geniculate nucleus (dLGN) to a light slit presented in a series of positions across the receptive field. The response was plotted against slit position, giv...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1993.70.4.1644
更新日期:1993-10-01 00:00:00
abstract::Studies on the expression and cellular function of sigma receptors in autonomic neurons were conducted in neonatal rat intracardiac and superior cervical (SCG) ganglia. Individual neurons from SCG and intracardiac ganglia were shown to express transcripts encoding the sigma-1 receptor using single-cell RT-PCR techniqu...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.2002.87.6.2867
更新日期:2002-06-01 00:00:00
abstract::Long-term depression (LTD) was induced in neocortical layer 5 pyramidal connections by pairing presynaptic firing with subthreshold postsynaptic depolarization (dLTD) or via a spike-timing protocol (tLTD). Like tLTD, dLTD reduced short-term depression and increased the coefficient of variation consistent with a presyn...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00376.2004
更新日期:2004-12-01 00:00:00
abstract::Mechanosensory neurons exhibit a wide range of dynamic changes in response, including rapid and slow adaptation. In addition to mechanical factors, electrical processes may also contribute to sensory adaptation. We have investigated adaptation of afferent neurons in the stick insect femoral chordotonal organ (fCO). Th...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00339.2002
更新日期:2002-11-01 00:00:00
abstract::The ability to adjust the amplitude of gaze shifts in response to persistent visual errors ("gaze adaptation") has been investigated primarily by introducing visual errors at the end of saccades produced by head-restrained primates. Very little is known about the behavior and neural mechanisms underlying gaze adaptati...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.90735.2008
更新日期:2009-01-01 00:00:00
abstract::The location of the human nociceptive area(s) near the Sylvian fissure is still controversial in spite of evidence from imaging and evoked potential studies that noxious heat stimuli activate somatosensory areas in that region. Some studies have suggested the secondary somatosensory cortex (SII) on the upper bank of t...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00772.2002
更新日期:2003-06-01 00:00:00
abstract::The spatial arrangement of preferred directions (PDs) in the primary motor cortex has revealed evidence for columnar organization and short-range order. We investigated the large-scale properties of this arrangement. We recorded neural activity at sites on a grid covering a large region of the arm area of the motor co...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00488.2006
更新日期:2006-12-01 00:00:00
abstract::1. We studied the blocking properties of a spider (Nephila clavata) toxin (JSTX) purified from venom on the spiny lobster neuromuscular junction. 2. When a small amount of JSTX was applied to the neuromuscular junction, the excitatory postsynaptic potential (EPSP) was partially suppressed. The amplitude of EPSPs remai...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1987.58.2.319
更新日期:1987-08-01 00:00:00
abstract::Synaptic drugs were superfused into turtle eyecup preparation while recording extracellularly from directionally sensitive (DS) retinal ganglion cells. As in previous experiments in intact rabbit retina, both picrotoxin (a GABA antagonist) and physostigmine [an acetylcholine (ACh) potentiator] reduced or eliminated th...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1985.54.5.1123
更新日期:1985-11-01 00:00:00
abstract::There is evidence that postural instability associated with Parkinson's disease (PD) is not adequately improved by levodopa, implying involvement of nondopaminergic pathways. However, the mechanisms contributing to postural instability have yet to be fully identified and tested for their levodopa responsiveness. In th...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00996.2015
更新日期:2016-08-01 00:00:00
abstract::A major goal of neuroscience is to understand the functions of networks of neurons in cognition and behavior. Recent work has focused on implanting arrays of ∼100 immovable electrodes or smaller numbers of individually adjustable electrodes, designed to target a few cortical areas. We have developed a recording system...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00625.2011
更新日期:2012-04-01 00:00:00
abstract::Single-unit activity of the motor cortex (area 4gamma) was studied in cats performing reaching with the contra- versus ipsilateral forelimb. Reaching was initiated by a tone burst (Go cue), different limbs were used in separate blocks of trials. During reaching performed with the contralateral limb, three types of neu...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00720.2003
更新日期:2005-05-01 00:00:00
abstract::Electrical stimulation of the median nerve at the wrist may elicit a blink reflex [hand blink reflex (HBR)] mediated by a neural circuit at brain stem level. As, in a Sherringtonian sense, the blink reflex is a defensive response, in a series of experiments we tested, in healthy volunteers, whether and how the HBR is ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00731.2011
更新日期:2012-02-01 00:00:00
abstract::The octopus cells of the posteroventral cochlear nucleus receive inputs from auditory-nerve fibers and form one of the major ascending auditory pathways. They respond to acoustic and electrical stimulation transiently and are believed to carry temporal information in the precise timing of their action potentials. The ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1997.78.2.872
更新日期:1997-08-01 00:00:00
abstract::1. We study the propagation and dynamics of spindle waves in thalamic slices by developing and analyzing a model of reciprocally coupled populations of excitatory thalamocortical (TC) neurons and inhibitory thalamic reticular (RE) neurons. 2. Each TC neuron has three intrinsic ionic currents: a low-threshold T-type Ca...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1996.75.2.750
更新日期:1996-02-01 00:00:00
abstract::To investigate the nature of the visuomotor transformation, previous studies have used pointing tasks and examined how adaptation to a spatially localized mismatch between vision and proprioception generalizes across the workspace. Whereas some studies found extensive spatial generalization of single-point remapping, ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00507.2007
更新日期:2008-01-01 00:00:00
abstract::1. The inhibitory response of exogenously applied glycine was investigated in freshly dissociated rat nucleus tractus solitarii neurons under whole cell configuration using new perforated patch-clamp technique termed "gramicidin perforated patch technique," which maintains intact intracellular Cl- concentrations. 2. U...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1994.72.3.1103
更新日期:1994-09-01 00:00:00
abstract::Intrathecally applied nicotine reduces bradykinin-induced plasma extravasation (BK-induced PE) in the rat knee joint. This depression is mediated by the hypothalamo-pituitary-adrenal (HPA) axis and is enhanced by interruption of impulse traffic in afferents of the abdominal vagus nerve. Like intrathecal nicotine, elec...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1997.78.3.1285
更新日期:1997-09-01 00:00:00
abstract::The phasing of neuronal activity in a rhythmic motor network is determined by a neuron's intrinsic firing properties and synaptic inputs; these could vary in their relative importance under different modulatory conditions. In the lobster pyloric network, the firing of eight follower pyloric (PY) neurons is shaped by t...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00440.2005
更新日期:2005-11-01 00:00:00
abstract::1. The responses of onset units in the cochlear nucleus of the anesthetized guinea pig have been measured to single tones, two-tone complexes, and broadband noise (BBN; 20-kHz bandwidth). The onset units were subdivided into three groups, onset-I (OnI), onset-L (OnL), and onset-C (OnC), on the basis of a decision tree...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1995.73.1.141
更新日期:1995-01-01 00:00:00
abstract::During early development neuronal networks express slow oscillating synchronized activity. The activity can be driven by several, not necessarily mutually exclusive, mechanisms. Each mechanism might have distinctive consequences for the phenomenology, formation, or sustainment of the early activity pattern. Here we st...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00889.2010
更新日期:2011-09-01 00:00:00
abstract::The role of metabotropic glutamate receptors (mGluRs) and adenosine receptors in hypoxia-induced suppression of excitatory synaptic input to interneurons residing at the granule cell-hilus border in the dentate gyrus was investigated with the use of whole cell electrophysiological recording techniques in thin (250 mic...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1997.77.1.393
更新日期:1997-01-01 00:00:00
abstract::It is an essential feature for the visual system to keep track of self-motion to maintain space constancy. Therefore the saccadic system uses extraretinal information about previous saccades to update the internal representation of memorized targets, an ability that has been identified in behavioral and electrophysiol...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00543.2004
更新日期:2005-03-01 00:00:00
abstract::Ablation and single-unit studies in primates have shown that inferior temporal (IT) cortex is important for pattern discrimination. The first paper in this series suggested that single units in IT cortex of alert monkeys respond to a set of two-dimensional patterns with complex temporal modulation of their spike train...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1987.57.1.162
更新日期:1987-01-01 00:00:00
abstract::1. Pressure on the skin of the tail base and perineum of female rats in the range of 40--440 millibars, following bilateral contact with the flanks, was adequate to elicit the lordosis reflex. Hair deflection alone or noxious stimulation was neither sufficient nor necessary for lordosis behavior to occur. 2. For a giv...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1979.42.1.195
更新日期:1979-01-01 00:00:00
abstract::The purpose of these studies was to determine the role of gracile nucleus and the effects of l-arginine-derived nitric oxide (NO) synthesis in the nucleus on the cardiovascular responses to electroacupuncture (EA) stimulation of "Zusanli" (ST36). Arterial blood pressure and heart rate were monitored during EA stimulat...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00170.2003
更新日期:2003-08-01 00:00:00