Abstract：
:Pioneering studies demonstrated that novel degrees of freedom could be controlled individually by directly encoding the firing rate of single motor cortex neurons, without regard to each neuron's role in controlling movement of the native limb. In contrast, recent brain-computer interface work has emphasized decoding outputs from large ensembles that include substantially more neurons than the number of degrees of freedom being controlled. To bridge the gap between direct encoding by single neurons and decoding output from large ensembles, we studied monkeys controlling one degree of freedom by comodulating up to four arbitrarily selected motor cortex neurons. Performance typically exceeded random quite early in single sessions and then continued to improve to different degrees in different sessions. We therefore examined factors that might affect performance. Performance improved with larger ensembles. In contrast, other factors that might have reflected preexisting synaptic architecture-such as the similarity of preferred directions-had little if any effect on performance. Patterns of comodulation among ensemble neurons became more consistent across trials as performance improved over single sessions. Compared with the ensemble neurons, other simultaneously recorded neurons showed less modulation. Patterns of voluntarily comodulated firing among small numbers of arbitrarily selected primary motor cortex (M1) neurons thus can be found and improved rapidly, with little constraint based on the normal relationships of the individual neurons to native limb movement. This rapid flexibility in relationships among M1 neurons may in part underlie our ability to learn new movements and improve motor skill.
journal_name
J Neurophysioljournal_title
Journal of neurophysiologyauthors
Law AJ,Rivlis G,Schieber MHdoi
10.1152/jn.00373.2013subject
Has Abstractpub_date
2014-09-15 00:00:00pages
1528-48issue
6eissn
0022-3077issn
1522-1598pii
jn.00373.2013journal_volume
112pub_type
杂志文章abstract：:Whole cell and cell-attached patch-clamp techniques characterized the neurosteroid anesthetic alphaxalone's (5alpha-pregnane-3alpha-ol-11,20-dione) effects on GABAA receptors and on Cl- currents in cultured embryonic (5- to 8-wk old) human dorsal root ganglion neurons. Alphaxalone applied by pressure pulses from close...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1999.82.1.10
更新日期：1999-07-01 00:00:00
abstract：:1. Semi-isolated preparations of the nine-celled cardiac ganglion of the crab, Portunus sanguinolentus, were studied electrophysiologically, using simultaneous recording from extracellular and two or three intracellular electrodes. Nine penetrations of small cells were achieved. 2. Three large (80 x 120 micron) cells ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1979.42.4.975
更新日期：1979-07-01 00:00:00
abstract：:CA1 inhibitory interneurons at the stratum lacunosum-moleculare and radiatum junction (LM/RAD-INs) display subthreshold membrane potential oscillations (MPOs) involving voltage-dependent Na(+) and A-type K(+) currents. LM/RAD-INs also express other voltage-gated K(+) currents, although their properties and role in MPO...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00848.2009
更新日期：2010-06-01 00:00:00
abstract：:This study examined the influence of proprioceptive input from hip flexor muscles on the activity in hip flexors during the swing phase of walking in the decerebrate cat. One hindlimb was partially denervated to remove cutaneous input and afferent input from most other hindlimb muscles. Perturbations to hip movement w...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2001.86.3.1321
更新日期：2001-09-01 00:00:00
abstract：:People perceive better in cardinal directions compared with oblique ones. This directional effect, called oblique effect, has been documented in perception studies for a long time. However, typical motor studies do not differentiate learning in different directions. In this study we identify a significant directional ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00787.2017
更新日期：2018-07-01 00:00:00
abstract：:The brain can precisely encode the temporal relationship between tactile inputs. While behavioural studies have demonstrated precise interfinger temporal judgments, the underlying neural mechanism remains unknown. Computationally, two kinds of neural responses can act as the information source. One is the phase-locked...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00790.2015
更新日期：2016-03-01 00:00:00
abstract：:1. Surgically resected tissue from the tip of the human temporal lobe of seven patients undergoing temporal lobectomy was employed to study functional properties of GABAergic inhibition mediated through activation of GABAA receptors, using patch-clamp recording techniques in acutely isolated neurons and in slices of h...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1996.75.4.1458
更新日期：1996-04-01 00:00:00
abstract：:Population spikes vary in size during prolonged epileptic ("ictal") discharges, indicating variations in neuronal synchronization. Here we investigate the role of changes in tissue electrical resistivity in this process. We used the rat hippocampal slice, low-Ca(2+) model of epilepsy and measured changes in pyramidal ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00123.2004
更新日期：2004-07-01 00:00:00
abstract：:Dopamine (DA) neurons and GABA neurons of the substantia nigra (SN) promote distinct functions in the control of movement and have different firing properties and action potential (AP) waveforms. APs recorded from DA and GABA neurons differed in amplitude, maximal rate of rise, and duration. In addition, the threshold...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00513.2009
更新日期：2010-06-01 00:00:00
abstract：:The nucleus accumbens (NAcc) is a brain region involved in functions ranging from motivation and reward to feeding and drug addiction. The NAcc is typically divided into two major subdivisions, the shell and the core. The primary output neurons of both of these areas are medium spiny neurons (MSNs), which are quiescen...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00766.2001
更新日期：2002-07-01 00:00:00
abstract：:An in vitro brain stem-spinal cord preparation from an adult urodele (Pleurodeles waltl) was developed in which two fictive rhythmic motor patterns were evoked by bath application of N-methyl-D-aspartate (NMDA; 2.5-10 microM) with D-serine (10 microM). Both motor patterns displayed left-right alternation. The first pa...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1999.82.2.1074
更新日期：1999-08-01 00:00:00
abstract：:1. Mechanoreceptor neurons in spider (Cupiennlus salei) slit sense organ were examined by intracellular current- and voltageclarry recordings. Steps and pseudorandomly modulated displacement stimuli were delivered to the mechanosensitive cuticular slits. The resulting responses were used to determine the response dyna...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1995.74.6.2513
更新日期：1995-12-01 00:00:00
abstract：:To study the possible role of the cerebellum in the vestibular-ocular reflex, extracellular responses of cerebellar nuclear neurons were recorded in awake monkeys during natural vestibular stimulation; 115 neurons in the fastigial nucleus responded to horizontal sinusoidal accelerations applied to the head by means of...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1975.38.3.627
更新日期：1975-05-01 00:00:00
abstract：:Neuron loss, axon sprouting, and the formation of new synaptic circuits have been hypothesized to contribute to seizures in temporal lobe epilepsy (TLE). Using the kainate-treated rat, we examined how alterations in the density of CA1 pyramidal cells and interneurons, and subsequent sprouting of CA1 pyramidal cell axo...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2001.85.1.1
更新日期：2001-01-01 00:00:00
abstract：:Increasing evidence demonstrates that modulating the cGMP-dependent protein kinase G (PKG) pathway produces an array of behavioral phenotypes in the fruit fly, Drosophila melanogaster. Altering PKG activity, either genetically via the foraging (for) gene or using pharmacology modifies tolerance to acute abiotic stress...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00784.2011
更新日期：2013-02-01 00:00:00
abstract：:1. Effects of deafferentation of the tooth pulps of the posterior mandibular teeth were studied in single neurons recorded in the ipsilateral subnucleus caudalis of the trigeminal (V) spinal tract nucleus of adult cats and kittens. The functional properties of neurons in each anesthetized animal were determined electr...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1989.61.6.1197
更新日期：1989-06-01 00:00:00
abstract：:Recent studies have shown that the initial responses evoked by a stimulus in neurons of primary visual cortex are dominated by low spatial frequency information in the image, whereas finer spatial scales dominate later in the response. Such phenomena could arise from the dynamics of receptive field (RF) size at early ...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00830.2006
更新日期：2007-01-01 00:00:00
abstract：:The responses of sustaining and dimming fibers were characterized by the time varying firing rates elicited by extrinsic current and flashes of light. These data were simulated by an adaptive integrate-and-fire model. A postimpulse shunt conductance simulated spike-frequency adaptation. The correlation between observe...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00035.2004
更新日期：2004-07-01 00:00:00
abstract：:The basal ganglia participate in motor functions and are implicated in the pathophysiology of movement disorders. It has been shown in primates that the activity of many neurons in one of the basal ganglia output nuclei, the internal segment of the globus pallidus, changes with active or passive movements. The involve...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.01180.2002
更新日期：2004-02-01 00:00:00
abstract：:To investigate the specificity of fusimotor (gamma) drive during locomotion, gamma-efferents were recorded from the flexor digitorum longus (FDL) and flexor hallucis longus (FHL) nerves in a decerebrate cat preparation. These nerves innervate hindlimb muscles that differ in some aspects of their mechanical action. For...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00917.2000
更新日期：2002-01-01 00:00:00
abstract：:The anterior branch of N. VIII was sectioned in adult frogs. Two months later the brain was isolated to record in vitro responses in the vestibular nuclei and from the abducens nerves following electric stimulation of the anterior branch of N. VIII or of the posterior canal nerve. Extra- and intracellularly recorded r...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.2000.84.1.581
更新日期：2000-07-01 00:00:00
abstract：:An acute experimental arthritis was induced in the right knee joint of adult cats anesthetized with chloralose, and the activity of single fine afferent units of the medial articular nerve was recorded from filaments of the saphenous nerve. All units included in this study were sensitive to local mechanical probing of...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1985.54.5.1109
更新日期：1985-11-01 00:00:00
abstract：:The scratch reflex is a motor task exhibited by the hindlimb of a turtle after complete transection of the spinal cord just posterior to the forelimb enlargement. The scratch is elicited by applying gentle tactile stimulation to a site innervated by spinal segments caudal to the level of the transection. During the sc...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1985.53.6.1501
更新日期：1985-06-01 00:00:00
abstract：:1. Voltage-dependent Na+ conductances were studied in small (18-25 microns diam) adult rat dorsal root ganglion (DRG) neurons with the use of the whole cell patch-clamp technique. Na+ currents were also recorded from larger (44-50 microns diam) neurons and compared with those of the small neurons. 2. The predominant N...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1994.72.6.2796
更新日期：1994-12-01 00:00:00
abstract：:1. The influence of prior metabotropic glutamate receptor (mGluR) activation on subsequent long-term potentiation (LTP) induction was investigated with the use of the mGluR agonist 1-amino-cyclopentane-1S,3R-dicarboxylic acid (ACPD, 20 microM). Field potential recordings were made in the stratum radiatum of CA1 slices...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1996.76.2.953
更新日期：1996-08-01 00:00:00
abstract：:Field potential recording was used to investigate properties of synaptic transmission and long-term potentiation (LTP) at Schaffer collateral-CA1 synapses in both hippocampal slices of mutant mice in which the alpha-subunit of the olfactory cyclic nucleotide-gated channel (alpha3/OCNC)1 was rendered null and also in s...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.1998.79.6.3295
更新日期：1998-06-01 00:00:00
abstract：:Complex movements are generally thought to consist of a series of simpler elements. If this is so, how does the sensorimotor system assemble the pieces? This study recorded and evaluated sequences of arm movements to various targets placed in three-dimensional (3D) space. Subjects performed sequences consisting of sin...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.01062.2002
更新日期：2003-06-01 00:00:00
abstract：:Contusion-type injuries to the spinal cord are characterized by tissue loss and disruption of spinal pathways. Midcervical spinal cord injuries impair the function of respiratory muscles and may contribute to significant respiratory complications. This study systematically assessed the impact of a 100-kDy unilateral C...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00727.2016
更新日期：2017-02-01 00:00:00
abstract：:The aim of this study was to investigate how maximal intermittent contractions for a hand muscle influence cortical and reflex activity, as well as the ability to voluntarily activate, the homologous muscle in the opposite limb. Twelve healthy subjects (age: 24 ± 3 years, all right hand dominant) performed maximal con...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00367.2016
更新日期：2016-11-01 00:00:00
abstract：:Individuals who have experienced a stroke often demonstrate inappropriate muscle activity phasing in the paretic leg during locomotion. Past research has demonstrated that inappropriate paretic phasing varies between behavioral contexts and is reduced during unilateral pedaling with the nonparetic leg inactive. We inv...
journal_title：Journal of neurophysiology
pub_type： 杂志文章
doi：10.1152/jn.00256.2017
更新日期：2018-06-01 00:00:00
