Abstract:
:The dorsal premotor area (PMd) of monkeys has been implicated in processes relating to movement preparation and movement selection. In the present study, we sought to determine whether PMd neurons that are activated during a delayed reaching task have directional responses that reflect either the target (i.e., the goal) of an intended movement or the physical properties of the movement itself. Two macaque monkeys were trained to perform a visually instructed, delayed reaching task with indirect visual feedback. The subjects and methods were identical to those described in the preceding paper. In the behavioral task, each subject moved a two-dimensional joystick with the right forelimb to align a cursor with targets presented on a video display. The paradigm dissociated the direction of forelimb movement from the spatial location of the target. This was accomplished by varying the spatial mappings between joystick and cursor. A variable delay separated the visual stimulus that instructed the target location (IS) from the visual stimulus that triggered the instructed movement (TS). Task-related activity was recorded from a total of 181 PMd neurons. The focus of this study was on directionally tuned neuronal responses that included 1) stimulus-related activity (phasic, following IS); 2) set-related activity (phasic, following IS and TS); and 3) movement-related activity (phasic, following TS). Of the entire sample of PMd neurons with directionally tuned activity, 114 were tested with two joystick/cursor mappings, permitting dissociation of directional responses that depended on limb trajectory from those that depended on target location. Task-related neuronal activity was classified as target-dependent if it covaried exclusively with target location across both conditions, and as limb-dependent if it covaried exclusively with limb trajectory. Directional activity that changed significantly across rotation conditions was classified as complex. Approximately one half of the sample of PMd neurons showed stimulus-related activity that was directionally tuned (56%, 64 of 114). Nearly all of the directionally classifiable stimulus-related activity was target dependent (94%, 44 of 47 responses), and none was limb dependent. A small proportion was classified as complex (6%, 3 of 47 responses). More than two thirds of the PMd neurons showed set-related activity that was directionally tuned (69%, 79 of 114). Among cells with set-related activity that was directionally classifiable, there were approximately 9 times as many target-dependent responses (76%, 48 of 63) as there were limb-dependent responses (8%, 5 of 63), with the remainder being complex (16%, 10 of 63). Approximately three quarters of the sample of PMd neurons showed early movement-related activity (before movement onset) that was directionally tuned (78%, 89 of 114). Among those cells whose early movement-related activity was directionally classifiable, there were > 3 times as many target-dependent responses ((51%, 34 of 66) as limb-dependent responses (14%, 9 of 66), with the remainder being complex (35%, 23 of 66). Approximately two thirds of the sample showed late movement-related responses (after movement onset) that were directionally tuned (68%, 78 of 114). Among those cells whose late movement-related activity was directionally classifiable, there were comparable numbers of target-dependent (25%, 15 of 61) and limb-dependent responses (28%, 17 of 61), with the remainder being complex (47%, 29 of 61). These results indicate a preferential representation of target location rather than limb trajectory among PMd neurons. Over the extended interval from IS to motor response, there was a gradual decline in the frequency of target-dependent activity and corresponding increases in the frequencies of both limb-dependent and complex activity. These findings suggest that PMd neurons may participate in mediating the sensory-to-motor transformation required by the delayed reaching
journal_name
J Neurophysioljournal_title
Journal of neurophysiologyauthors
Shen L,Alexander GEdoi
10.1152/jn.1997.77.3.1195subject
Has Abstractpub_date
1997-03-01 00:00:00pages
1195-212issue
3eissn
0022-3077issn
1522-1598journal_volume
77pub_type
杂志文章abstract::Octopus arms, as well as other muscular hydrostats, are characterized by a very large number of degrees of freedom and a rich motion repertoire. Over the years, several attempts have been made to elucidate the interplay between the biomechanics of these organs and their control systems. Recent developments in electrop...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00739.2006
更新日期:2007-09-01 00:00:00
abstract::Visual search is a ubiquitous visual behavior, and efficient search is essential for survival. Different cognitive models have explained the speed and accuracy of search based either on the dynamics of attention or on similarity of item representations. Here, we examined the extent to which performance on a visual sea...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00569.2016
更新日期:2017-01-01 00:00:00
abstract::1. In order to investigate the effects of an imbalance in stimulation to the eyes without the confounding influence of continuous deprivation of one eye, we reared cats with unequal alternating monocular exposure (AME) and, for comparison, cats with equal AME. We recorded extracellularly from single cells in area 17 o...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1983.49.3.804
更新日期:1983-03-01 00:00:00
abstract::A spherical approximation technique is presented that affords a mathematical characterization of a virtual space receptive field (VSRF) based on first-spike latency in the auditory cortex of cat. Parameterizing directional sensitivity in this fashion is much akin to the use of difference-of-Gaussian (DOG) functions fo...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1998.80.5.2645
更新日期:1998-11-01 00:00:00
abstract::It is well recognized that the brain uses sensory information to accurately produce motor commands. Indeed, most research into the relationship between sensory and motor systems has focused on how sensory information modulates motor function. In contrast, recent studies have begun to investigate the reverse: how senso...
journal_title:Journal of neurophysiology
pub_type: 杂志文章,随机对照试验
doi:10.1152/jn.00949.2010
更新日期:2011-05-01 00:00:00
abstract::Experiments have been carried out on the soleus muscle and its tendon in the anesthetized cat. Measurements of isometric tension and muscle stiffness were made during contraction of whole or part of the muscle in response to stimulation of ventral root filaments. In an attempt to determine the distribution of tension ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1984.52.3.459
更新日期:1984-09-01 00:00:00
abstract::Current and voltage-clamp recordings were made at room temperature from cultured mouse spinal neurons using conventional two-electrode voltage-clamp techniques and electrodes filled with either 3 M KCl, 3 M CsCl, or 3 M Cs2SO4. In the presence of tetraethylammonium and tetrodotoxin, "fast" (rapidly rising and falling)...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1986.55.6.1115
更新日期:1986-06-01 00:00:00
abstract::A mathematical model is developed for simulation of action potential propagation through a single branch point of a myelinated nerve fiber with a parent branch bifurcating into two identical daughter branches. This model is based on a previously published multi-layer compartmental model for single unbranched myelinate...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.2001.85.1.197
更新日期:2001-01-01 00:00:00
abstract::Rewards in the natural environment are rarely predicted with complete certainty. Uncertainty relating to future rewards has typically been defined as the variance of the potential outcomes. However, the asymmetry of predicted reward distributions, known as skewness, constitutes a distinct but neuroscientifically under...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00471.2011
更新日期:2011-11-01 00:00:00
abstract::The locus coeruleus (LC) noradrenergic (NE) neuromodulatory system is critically involved in regulation of neural excitability via its diffuse ascending projections. Tonic NE release in the forebrain is essential for maintenance of vigilant states and increases the signal-to-noise ratio of cortical sensory responses. ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00552.2017
更新日期:2018-03-01 00:00:00
abstract::The neuromodulator acetylcholine (ACh) shapes neocortical function during sensory perception, motor control, arousal, attention, learning, and memory. Here we investigate the mechanisms by which ACh affects neocortical pyramidal neurons in adult mice. Stimulation of cholinergic axons activated muscarinic and nicotinic...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00716.2014
更新日期:2015-04-01 00:00:00
abstract::We studied the effects of fatigue of the index finger on indices of force variability in discrete and rhythmic accurate force production tasks performed by the index finger and by all four fingers pressing in parallel. An increase in the variance of the force produced by the fatigued index finger was expected. We hypo...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00077.2010
更新日期:2010-06-01 00:00:00
abstract::Although G-protein-coupled (metabotropic) receptors are known to modulate the production of motor patterns, evidence from the escape swim central pattern generator (CPG) of the nudibranch mollusk, Tritonia diomedea, suggests that they might also participate in the generation of the motor pattern itself. The dorsal swi...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.2001.85.1.476
更新日期:2001-01-01 00:00:00
abstract::During auditory stimulation with several frequency components, distortion products (DPs) are generated as byproduct of nonlinear cochlear amplification. After generated, DP energy is reemitted into the ear channel where it can be measured as DP otoacoustic emission (DPOAE), and it also induces an excitatory response a...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.90805.2008
更新日期:2009-03-01 00:00:00
abstract::Membrane-permeable arachidonic acid (AA) is liberated in a Ca2+-dependent way inside cells. By using whole cell patch clamp we show that intracellular AA (1 pM) selectively reduces IA in rat hippocampal neurons, whereas extracellular application requires a 10(6)-fold concentration. The nonmetabolized AA analogue ETYA ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1999.82.1.508
更新日期:1999-07-01 00:00:00
abstract::Behavioral, ethological, and electrophysiological evidence suggests that the highly unpleasant, bitter taste of a concentrated quinine hydrochloride (QHCL) should activate the human amygdala. In the present study, healthy subjects tasted 0.02 M QHCL or water while regional cerebral blood flow (rCBF) was assayed with H...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00358.2001
更新日期:2002-02-01 00:00:00
abstract::1. We examined excitation and the facilitatory effect on the heat responses induced by histamine in visceral polymodal receptors with the use of the canine testis-spermatic nerve preparation in vitro. 2. The proportion of units that showed excitation (> 10 impulses 1 min after application of histamine was initiated) i...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1996.76.3.1396
更新日期:1996-09-01 00:00:00
abstract::1. Opaline release in Aplysia provides a simple model system for examining the biochemical and electrophysiological mechanisms underlying glandular secretion and its modulation. The opaline gland is a large multivesicular structure, which is innervated by at least three large identified motor neurons located within th...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1982.48.6.1347
更新日期:1982-12-01 00:00:00
abstract::1. Current- and voltage-clamp studies were conducted on isolated rat adrenal chromaffin cells to identify the voltage-dependent ion channels mediating inward currents. 2. Mean resting membrane potential of the isolated cells was -62 +/- 3 (SE) mV. Evoked action potentials were both Na+ and Ca2+ based, and whole cell v...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1996.76.2.1195
更新日期:1996-08-01 00:00:00
abstract::The intermediate and deep layers of the monkey superior colliculus (SC) are known to be important for the generation of saccadic eye movements. Recent studies have also provided evidence that the rostral SC might be involved in the control of pursuit eye movements. However, because rostral SC neurons respond to visual...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.2001.86.5.2629
更新日期:2001-11-01 00:00:00
abstract::Neurons in area MT, a motion-sensitive area of extrastriate cortex, respond to a step of target velocity with a transient-sustained firing pattern. The transition from a high initial firing rate to a lower sustained rate occurs over a time course of 20-80 ms and is considered a form of short-term adaptation. The prese...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00852.2001
更新日期:2002-07-01 00:00:00
abstract::The dye Procion brown was used to identify in the light and electron microscope, synaptic contacts made between monosynaptically coupled neurons in the lamprey spinal cord whose synaptic interaction had been recorded. Synaptic contacts were made on different dendrites of the postsynaptic cell at different distances fr...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1976.39.2.197
更新日期:1976-03-01 00:00:00
abstract::The excitatory and inhibitory conductances driving the light-evoked currents (LECs) of cat and ferret ON- and OFF-center X ganglion cells were examined in sliced and isolated retina preparations using center spot stimulation in tetrodotoxin (TTX)-containing Ringer. ON-center X ganglion cells showed an increase in an e...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1998.80.6.2975
更新日期:1998-12-01 00:00:00
abstract::The spinal cord has been well established as the site of generation of the locomotor rhythm in vertebrates, but studies have suggested that the caudal hindbrain in larval fish and amphibians can also generate locomotor rhythms. Here, we investigated whether the caudal hindbrain of the adult lamprey ( Petromyzon marinu...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00851.2017
更新日期:2018-05-01 00:00:00
abstract::Cultured Kenyon cells from the mushroom body of the honeybee, Apis mellifera, show a voltage-gated, fast transient K+ current that is sensitive to 4-aminopyridine, an A current. The kinetic properties of this A current and its modulation by extracellular K+ ions were investigated in vitro with the whole cell patch-cla...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1999.81.4.1749
更新日期:1999-04-01 00:00:00
abstract::1. The primary functions of the superior colliculus (SC) are thought to include both the spatial localization of sensory stimuli and the initiation of an orienting response. It has been hypothesized that, in cat, both of these SC functions may be influenced by feedback from the extraocular muscles. The present investi...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1989.62.6.1360
更新日期:1989-12-01 00:00:00
abstract::One of the fundamental principles of neuroscience is that direct electrical interactions between neurons are not possible without specialized electrical contacts, gap junctions, because the transmembrane resistance of neurons is typically much higher than the resistance of the adjacent extracellular space. However it ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00098.2005
更新日期:2006-03-01 00:00:00
abstract::Augmenting (or incremental) responses are progressively growing potentials elicited by 5- to 15-Hz stimulation within the thalamus, cerebral cortex, or by setting into action reciprocal thalamocortical neuronal loops. These responses are associated with short-term plasticity processes in thalamic and cortical neurons....
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.1998.79.5.2716
更新日期:1998-05-01 00:00:00
abstract::Although the patterns of activity produced by neocortical networks are now better understood, how these states are activated, sustained, and terminated still remains unclear. Negative feedback by the endogenous neuromodulator adenosine may potentially play an important role, as it can be released by activity and there...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00620.2014
更新日期:2015-02-01 00:00:00
abstract::Propriospinal interneurons in the thoracic spinal cord have vital roles not only in controlling respiratory and trunk muscles, but also in providing possible substrates for recovery from spinal cord injury. Intracellular recordings were made from such interneurons in anesthetized cats under neuromuscular blockade and ...
journal_title:Journal of neurophysiology
pub_type: 杂志文章
doi:10.1152/jn.00738.2010
更新日期:2011-02-01 00:00:00