scholarly journals A chronic neural interface to the macaque dorsal column nuclei

2016 ◽  
Vol 115 (5) ◽  
pp. 2255-2264 ◽  
Author(s):  
Andrew G. Richardson ◽  
Pauline K. Weigand ◽  
Srihari Y. Sritharan ◽  
Timothy H. Lucas
Keyword(s):  
Brain Stem ◽  
Receptive Fields ◽  
Dorsal Column ◽  
Single Units ◽  
Field Potentials ◽  
Dorsal Column Nuclei ◽  
Unit Recording ◽  
Somatosensory Information ◽  
The Stability ◽  
The Brain

The dorsal column nuclei (DCN) of the brain stem contain secondary afferent neurons, which process ascending somatosensory information. Most of the known physiology of the DCN in primates has been acquired in acute experiments with anesthetized animals. Here, we developed a technique to implant a multielectrode array (MEA) chronically in the DCN of macaque monkeys to enable experiments with the animals awake. Two monkeys were implanted with brain-stem MEAs for 2–5 mo with no major adverse effects. Responses of the cuneate and gracile nuclei were quantified at the level of both field potentials and single units. Tactile receptive fields (RFs) were identified for 315 single units. A subset of these units had very regular spiking patterns with spike frequencies predominantly in the alpha band (8–14 Hz). The stability of the neuronal recordings was assessed with a novel analysis that identified units by their mean spike waveform and by the spike-triggered average of activity on all other electrodes in the array. Fifty-six identified neurons were observed over two or more sessions and in a few cases for as long as 1 mo. RFs of stable neurons were largely consistent across days. The results demonstrate that a chronic DCN implant in a macaque can be safe and effective, yielding high-quality unit recording for several months. The unprecedented access to these nuclei in awake primates should lead to a better understanding of their role in sensorimotor behavior.

Sensorimotor Integration at the Dorsal Column Nuclei

Physiology ◽  
1999 ◽  
Vol 14 (6) ◽  
pp. 231-237
Author(s):  
Jorge Mariño ◽  
Luis Martinez ◽  
Antonio Canedo
Keyword(s):  
Sensorimotor Integration ◽  
Receptive Fields ◽  
Central Zone ◽  
Spatial Localization ◽  
Peripheral Zone ◽  
Dorsal Column ◽  
Primary Afferents ◽  
Zone Of Inhibition ◽  
Dorsal Column Nuclei ◽  
Recurrent Collaterals

Interaction among primary afferents, corticofugal fibers, and intrinsic elements allows for sensorimotor integration at the dorsal column nuclei. The interneurons permit the spatial localization, the recurrent collaterals synchronize the activity of projecting cells with overlapping receptive fields, and the corticofugal fibers induce a central zone of activity surrounded by a peripheral zone of inhibition.

Lateral cervical nucleus in the cat: functional organization and characteristics

1978 ◽  
Vol 41 (6) ◽  
pp. 1511-1534 ◽  
Author(s):  
A. D. Craig ◽  
D. N. Tapper
Keyword(s):  
Receptive Field ◽  
Receptive Fields ◽  
Dorsal Column ◽  
Receptor Type ◽  
Noxious Stimulation ◽  
Type I ◽  
Medial Lemniscus ◽  
Dorsal Column Nuclei ◽  
Lateral Cervical Nucleus ◽  
Stimulation Of

1. The lateral cervical nucleus (LCN) was investigated with extracellular recordings in the anesthetized cat. A total of 556 LCN units were characterized; the locations of most of these were histologically verified. Half of these had receptive fields on the rostral third of the ipsilateral body surface including the face; 14% had fields on the thorax or abdomen, 33% had fields on the hindlimb or tail, and about 3% had receptive fields larger than one limb. 2. The LCN was observed to be somatotopically organized in experiments using angled microelectrode penetrations. Hindlimb units were dorsolateral, forelimb units ventromedial, and face units most medial within the LCN. In regions where LCN cells were present only in the medial portion of the dorsolateral funiculus, they were all forelimb units. 3. A special subpopulation (17%) of cells were clustered most ventromedially in the LCN. These units had large or disjoint receptive fields, and/or responded to deep, visceral, or noxious stimulation. A third of these did not project in the medial lemniscus (ML); many were synaptically activated by stimulation of the ML. Those that did project in the ML had significantly longer latencies than all other LCN units. It is suggested that this subpopulation contains local LCN interneurons. 4. The specific mechanoreceptor inputs were identified for each of 121 projecting LCN units. Receptor inputs were uniform across each receptive field; that is, each unit that responded to a given receptor type was observed to respond to receptors of that type throughout its receptive field. Input from large-fiber-diameter, velocity-sensitive mechanoreceptors was predominant. The absence of input from slowly adapting type I and II receptors and from joint receptors was confirmed. A significant number of units (17.3%) could be driven by only one receptor type. The LCN sample profile agrees closely with the receptor representation in the hindlimb portion of the spinocervical tract. It is concluded that these data that anatomic specification of convergence occurs in the LCN with respect to receptor connectivity, and that this specification originates in lamina IV of the dorsal horn. 5. Stimulation of the dorsal column nuclei synaptically excited 23% of the LCN units tested. In two cases it was possible to demonstrate, by collision, that this occurred via collaterals of spinocervical tract axons. It is concluded that some spinocervical axons have collaterals terminating in the rostral parts of the dorsal column nuclei.

Far field potentials from the brain stem after transcutaneous vagus nerve stimulation

2003 ◽  
Vol 110 (12) ◽  
pp. 1437-1443 ◽  
Author(s):  
A. J. Fallgatter ◽  
B. Neuhauser ◽  
M. J. Herrmann ◽  
A.-C. Ehlis ◽  
A. Wagener ◽  
...  
Keyword(s):  
Vagus Nerve ◽  
Brain Stem ◽  
Nerve Stimulation ◽  
Vagus Nerve Stimulation ◽  
Far Field ◽  
Field Potentials ◽  
Transcutaneous Vagus Nerve Stimulation ◽  
The Brain

scholarly journals Somatosensory control of balance during locomotion in decerebrated cat

2012 ◽  
Vol 107 (8) ◽  
pp. 2072-2082 ◽  
Author(s):  
Pavel Musienko ◽  
Gregoire Courtine ◽  
Jameson E. Tibbs ◽  
Vyacheslav Kilimnik ◽  
Alexandr Savochin ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Brain Stem ◽  
Spinal Cord Stimulation ◽  
Balance Control ◽  
Dynamic Balance ◽  
Weight Bearing ◽  
The Body ◽  
Emg Activity ◽  
Somatosensory Information ◽  
The Brain

Postmammillary decerebrated cats can generate stepping on a moving treadmill belt when the brain stem or spinal cord is stimulated tonically and the hindquarters are supported both vertically and laterally. While adequate propulsion seems to be generated by the hindlimbs under these conditions, the ability to sustain equilibrium during locomotion has not been examined extensively. We found that tonic epidural spinal cord stimulation (5 Hz at L5) of decerebrated cats initiated and sustained unrestrained weight-bearing hindlimb stepping for extended periods. Detailed analyses of the relationships among hindlimb muscle EMG activity and trunk and limb kinematics and kinetics indicated that the motor circuitries in decerebrated cats actively maintain equilibrium during walking, similar to that observed in intact animals. Because of the suppression of vestibular, visual, and head-neck-trunk sensory input, balance-related adjustments relied entirely on the integration of somatosensory information arising from the moving hindquarters. In addition to dynamic balance control during unperturbed locomotion, sustained stepping could be reestablished rapidly after a collapse or stumble when the hindquarters switched from a restrained to an unrestrained condition. Deflecting the body by pulling the tail laterally induced adaptive modulations in the EMG activity, step cycle features, and left-right ground reaction forces that were sufficient to maintain lateral stability. Thus the brain stem-spinal cord circuitry of decerebrated cats in response to tonic spinal cord stimulation can control dynamic balance during locomotion using only somatosensory input.

A thalamic terminus of the lateral cervical nucleus: the lateral division of the posterior nuclear group

1986 ◽  
Vol 56 (6) ◽  
pp. 1498-1520 ◽  
Author(s):  
R. S. Metherate ◽  
D. C. da Costa ◽  
P. Herron ◽  
R. W. Dykes
Keyword(s):  
Receptive Fields ◽  
Frontal Plane ◽  
Dorsal Column ◽  
Excitatory Input ◽  
The Body ◽  
Dorsal Column Nuclei ◽  
Posterior Thalamus ◽  
Afferent Fibers ◽  
Lateral Cervical Nucleus ◽  
Nuclear Group

The submodality and receptive field properties of single units in the lateral cervical nucleus (LCN) of barbiturate anesthetized cats were studied with glass microelectrodes. In other experiments, a region of the posterior thalamus containing neurons with properties comparable to those seen in the LCN was examined with tungsten microelectrodes. The responses of most units in the LCN reflected a major input from large myelinated afferent fibers innervating guard hairs but no input from Pacinian afferent fibers. The large size of the receptive fields indicated that excitatory input converged selectively from afferent fibers serving hairs over large areas of the body. In the posterior thalamus rapidly adapting neurons characterized by very large receptive fields and driven by the movement of guard hairs were observed to a region identified histologically as the rostral extension of the lateral division of the posterior nuclear group (POl). Caudally this region was located immediately adjacent to the dorsolateral part of the ventroposterior inferior nucleus (VPI). In more rostral parts of the thalamus it was located more dorsally and the ventroposterior lateral nucleus intervened between it and the VPI. This region was less than 1 mm wide in the frontal plane but extended rostrocaudally for several millimeters. Horseradish peroxidase injected into the region of the VPI and the POl labeled many cells in the LCN and the caudal pole of the dorsal column nuclei demonstrating that neurons in the LCN relay information to this part of the thalamus. These data, plus previous experiments showing that the VPI receives a major projection from the caudal poles of the dorsal column nuclei, suggest that the rostral portion of the POl receives an important afferent supply from the LCN. The responses of neurons in the POl appear to arise from specific classes of sensory receptors and cannot be considered less precise or more primitive than responses observed in the ventroposterior nucleus of the thalamus.

scholarly journals The Dorsal Column Nuclei Neuroanatomy Reveals A Complex Sensorimotor Integration and Distribution Hub

2019 ◽  
Author(s):  
Alastair J. Loutit ◽  
Richard M. Vickery ◽  
Jason R. Potas
Keyword(s):  
Sensorimotor Integration ◽  
Dorsal Column ◽  
Proprioceptive Information ◽  
Dorsal Column Nuclei ◽  
Diverse Range ◽  
Somatosensory Information ◽  
Functional Implications ◽  
Complex Integration ◽  
Sensorimotor Information ◽  
Afferent Inputs

The dorsal column nuclei (DCN) are organised by both somatotopy and modality, and have a diverse range of afferent inputs and projection targets. The functional organisation and connectivity of the DCN implicate them in a variety of sensorimotor functions, beyond their commonly accepted role in processing and transmitting somatosensory information to the thalamus, yet this is largely underappreciated in the literature. In this review, we examine the morphology, organisation, and connectivity of the DCN and their associated nuclei, to improve understanding of their sensorimotor functions. First, we briefly discuss the receptors, afferent fibres, and pathways involved in conveying tactile and proprioceptive information to the DCN. Next, we review the modality and somatotopic arrangements of the constituents of the dorsal column nuclei complex (DCN-complex), which includes the gracile, cuneate, external cuneate, X, and Z nuclei, and Bischoff’s nucleus. Finally, we examine and discuss the functional implications of the myriad of DCN-complex projection targets throughout the midbrain, and hindbrain, in addition to their modulatory inputs from the cortex. The organisation and connectivity of the DCN-complex suggest that these nuclei should be considered a complex integration and distribution hub for sensorimotor information.

scholarly journals Insulin-Like Growth Factor I Modifies Electrophysiological Properties of Rat Brain Stem Neurons

2003 ◽  
Vol 89 (6) ◽  
pp. 3008-3017 ◽  
Author(s):  
Angel Nuñez ◽  
Eva Carro ◽  
Ignacio Torres-Aleman
Keyword(s):  
Growth Factor ◽  
Brain Stem ◽  
Dorsal Column ◽  
Excitatory Postsynaptic Potential ◽  
Insulin Like Growth Factor ◽  
Electrophysiological Properties ◽  
Factor I ◽  
Igf I ◽  
Growth Factor I ◽  
The Brain

On systemic injection, insulin-like growth factor I (IGF-I) elicits a prolonged increase in the excitability of dorsal column nuclei (DCN) cells in the brain stem as well as other target neurons within the brain. We have explored the cellular mechanisms involved in the stimulatory effects of IGF-I as well as its functional consequences. In a rat slice preparation, IGF-I induced a sustained depolarization of 2–5 mV in 81% of DCN neurons. Depolarization was accompanied with an increase in the input resistance (15%). Voltage-clamp recordings displayed that IGF-I decreased a K+-mediated A current (60%). Furthermore, IGF-I increased, in 78% of cells, the peak amplitude (25%), and rising slope (32%) of the excitatory postsynaptic potential evoked by dorsal column stimulation; in this case, a presynaptic facilitatory process appears to be involved. When anesthetized adult rats are injected in the carotid artery with IGF-I, extracellularly recorded propioceptive DCN neurons not only show increased spike activity but also an expansion of their cutaneous receptive field in 83% of DCN cells. Significantly, the increased excitability evoked by IGF-I in the DCN cells depends both in vivo and in vitro, on activation of p38 mitogen-activated protein kinase (MAPK), a Ser-kinase known to modulate K+ channel activity. We concluded that systemic IGF-I modulated the electrophysiological properties of target neurons within the brain. In turn, these changes probably contribute to functional reorganization processes such as expansion of neuronal receptive fields.

Control of Size and Excitability of Mechanosensory Receptive Fields in Dorsal Column Nuclei by Homolateral Dorsal Horn Neurons

1998 ◽  
Vol 80 (1) ◽  
pp. 120-129 ◽  
Author(s):  
Robert W. Dykes ◽  
A. D. Craig
Keyword(s):  
Spinal Cord ◽  
Receptive Field ◽  
Dorsal Horn ◽  
Cobalt Chloride ◽  
Receptive Fields ◽  
Dorsal Column ◽  
Field Size ◽  
Dorsal Column Nuclei ◽  
Receptive Field Size ◽  
Dorsal Horn Neurons

Dykes, Robert W. and A. D. Craig. Control of size and excitability of mechanosensory receptive fields in dorsal column nuclei by homolateral dorsal horn neurons. J. Neurophysiol. 80: 120–129 1998. Both accidental and experimental lesions of the spinal cord suggest that neuronal processes occurring in the spinal cord modify the relay of information through the dorsal column-lemniscal pathway. How such interactions might occur has not been adequately explained. To address this issue, the receptive fields of mechanosensory neurons of the dorsal column nuclei were studied before and after manipulation of the spinal dorsal horn. After either a cervical or lumbar laminectomy and exposure of the dorsal column nuclei in anesthetized cats, the representation of the hindlimb or of the forelimb was defined by multiunit recordings in both the dorsal column nuclei and in the ipsilateral spinal cord. Next, a single cell was isolated in the dorsal column nuclei, and its receptive field carefully defined. Each cell could be activated by light mechanical stimuli from a well-defined cutaneous receptive field. Generally the adequate stimulus was movement of a few hairs or rapid skin indentation. Subsequently a pipette containing either lidocaine or cobalt chloride was lowered into the ipsilateral dorsal horn at the site in the somatosensory representation in the spinal cord corresponding to the receptive field of the neuron isolated in the dorsal column nuclei. Injection of several hundred nanoliters of either lidocaine or cobalt chloride into the dorsal horn produced an enlargement of the receptive field of the neuron being studied in the dorsal column nuclei. The experiment was repeated 16 times, and receptive field enlargements of 147–563% were observed in 15 cases. These data suggest that the dorsal horn exerts a tonic inhibitory control on the mechanosensory signals relayed through the dorsal column-lemniscal pathway. Because published data from other laboratories have shown that receptive field size is controlled by signals arising from the skin, we infer that the control of neuronal excitability, receptive field size and location for lemniscal neurons is determined by tonic afferent activity that is relayed through a synapse in the dorsal horn. This influence of dorsal horn neurons on the relay of mechanosensory information through the lemniscal pathways must modify our traditional views concerning the relative independence of these two systems.

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