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Richard E. Poppele - One of the best experts on this subject based on the ideXlab platform.
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Kinematic and non-kinematic signals transmitted to the cat cerebellum during passive treadmill stepping
Experimental brain research, 2005Co-Authors: Gianfranco Bosco, J. Eian, Richard E. PoppeleAbstract:Previous work from this laboratory has shown that activity in the Dorsal Spinocerebellar Tract (DSCT) relates strongly to global hindlimb kinematics variables during passive displacements of the hindlimb. A linear relationship to limb axis orientation and length variables accounts for most of the response variance for passive limb positioning and movement. Here we extend those observations to more natural movements by examining the information carried by the DSCT during passive stepping movements on a treadmill, and we compare it to information transmitted during passive robot-driven hindlimb movements. Using a principal component analysis approach, we found that a linear relationship between the responses and hindlimb kinematics was comparable across experimental conditions. We also observed systematic non-linearities in this relationship for both types of movement that could be attributed to events corresponding to the touch-down and lift-off phases of the movement. We concluded that proprioceptive information transmitted to the cerebellum by the DSCT during locomotion has at least two major components. One component is associated with limb kinematics (limb orientation) and may be more or less related to the metrics of the step (stride length, for example) or its velocity. The other component is associated with limb length and/or limb loading, and it may signal some aspect of limb stiffness.
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Dorsal Spinocerebellar Tract neurons respond to contralateral limb stepping
Experimental brain research, 2003Co-Authors: Richard E. Poppele, A. Rankin, J. EianAbstract:Proprioceptive sensory information carried by Spinocerebellar Tracts provides a major input to the spinocerebellum, which has an important role in coordinating motor output for posture and locomotion. Until recently it was assumed that the information transmitted by the Dorsal Spinocerebellar Tract (DSCT) was organized to represent single muscles or single joints in the ipsilateral hindlimb. Recent studies have shown, however, that DSCT activity represents global kinematic parameters of the hindlimb. We now present evidence that the DSCT neurons are also modulated by passive step-like movements of either hindlimb, implying they receive a bilateral sensory input. About two-thirds of 78 cells studied had significant responses to movements of the contralateral limb alone and about 70% responded differently to bipedal movements than to ipsilateral movement alone. The same basic behavior was observed in anesthetized, paralyzed cats and in unanesthetized, decerebrate cats, although decerebrate cats may have had larger responses on average. The results suggest that many DSCT cells may encode information about interlimb coordination.
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Proprioception from a Spinocerebellar perspective.
Physiological reviews, 2001Co-Authors: Gianfranco Bosco, Richard E. PoppeleAbstract:This review explores how proprioceptive sensory information is organized at spinal cord levels as it relates to a sense of body position and movement. The topic is considered in an historical context and develops a different framework that may be more in tune with current views of sensorimotor processing in other central nervous system structures. The Dorsal Spinocerebellar Tract (DSCT) system is considered in detail as a model system that may be considered as an end point for the processing of proprioceptive sensory information in the spinal cord. An analysis of this system examines sensory processing at the lowest levels of synaptic connectivity with central neurons in the nervous system. The analysis leads to a framework for proprioception that involves a highly flexible network organization based in some way on whole limb kinematics. The functional organization underlying this framework originates with the biomechanical linkages in the limb that establish functional relationships among the limb segments. Afferent information from limb receptors is processed further through a distributed neural network in the spinal cord. The result is a global representation of hindlimb parameters rather than a muscle-by-muscle or joint-by-joint representation.
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Information processing in the Spinocerebellar system.
Neuroreport, 2000Co-Authors: Maria Stella Valle, Gianfranco Bosco, Richard E. PoppeleAbstract:The purpose of this study was to determine whether sensory information about limb kinematics relayed to the cerebellum over Spinocerebellar pathways may be modified at the cerebellar level. We tested this by recording from Dorsal Spinocerebellar Tract (DSCT) and Purkinje cells under the same experimental conditions in which the hindlimbs of anesthetized cats were passively moved through a series of step-like movement cycles. A population analysis of the response behavior showed that DSCT neurons encode a combination of limb axis position and movement velocity, whereas the Purkinje cells located in the DSCT cerebellar target areas encode limb axis velocity and position independently. We conclude from this that the cerebellum may somehow exTract a velocity component from the afferent input signal.
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Representation of Multiple Kinematic Parameters of the Cat Hindlimb in Spinocerebellar Activity
Journal of neurophysiology, 1997Co-Authors: Gianfranco Bosco, Richard E. PoppeleAbstract:Bosco, G. and R. E. Poppele. Representation of multiple kinematic parameters of the cat hindlimb in Spinocerebellar activity. J. Neurophysiol. 78: 1421–1432, 1997. Dorsal Spinocerebellar Tract (DSC...
Peter J. Soja - One of the best experts on this subject based on the ideXlab platform.
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State-related inhibition by GABA and glycine of transmission in Clarke’s column
2013Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Peter J. SojaAbstract:During the state of active sleep (AS), Clarke’s column Dorsal Spinocerebellar Tract (DSCT) neurons undergo a marked reduction in their spontaneous and excitatory amino acid (EAA)evoked responses. The present study was performed to examine the magnitude, consistency of AS-specific suppression, and potential role of classical inhibitory amino acids GABA and glycine (GLY) in mediating this phenomenon. AS-specific suppression of DSCT neurons, expressed as the reduction in mean spontaneous firing rate during AS versus the preceding episode of wakefulness, was compared across three consecutive sleep cycles (SC), each consisting of wakefulness (W), AS, and awakening from AS (RW). Spontaneous spike rate did not differ during W or RW between SC1, SC2, and SC3. AS-specific suppression of spontaneous firing rate was found to be consistent and measured 40.3, 31.5, and 41.6 % in SC1
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State-dependent GABAergic inhibition of sciatic nerve-evoked responses of Dorsal Spinocerebellar Tract neurons.
Journal of neurophysiology, 2004Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Angela Chan, Sylvia Chow, Lizbeth Fabian, Peter J. SojaAbstract:Peripheral nerve-evoked potentials recorded in the cerebellum 35 yr ago inferred that sensory transmission via the Dorsal Spinocerebellar Tract (DSCT) is reduced occasionally and only during eye mo...
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On the reduction of spontaneous and glutamate-driven Spinocerebellar and spinoreticular Tract neuronal activity during active sleep.
Neuroscience, 2001Co-Authors: Peter J. Soja, Niwat Taepavarapruk, B E Cairns, Walton Pang, Shelly A. McerlaneAbstract:AbsTract The present study was performed to provide evidence that dynamic neural processes underlie the reduction in Dorsal Spinocerebellar Tract and spinoreticular Tract neuron activity that occurs during active sleep. To ascertain the effect of local inhibition on the spontaneous and glutamate-evoked spike discharge of sensory Tract neurons, preliminary control tests were performed during the state of quiet wakefulness, where GABA or glycine was co-administered in a sustained fashion during pulsatile release of glutamate to Dorsal Spinocerebellar Tract ( n =3) or spinoreticular Tract ( n =2) neurons. Co-administration of GABA or glycine also resulted in a significant marked suppression of spontaneous spike activity and glutamate-evoked responses of these cells. Extracellular recording experiments combined with juxtacellular application of glutamate were then performed on 20 antidromically identified Dorsal Spinocerebellar Tract and spinoreticular Tract neurons in the chronic intact cat as a function of sleep and wakefulness. The glutamate-evoked activity of a group of 10 sensory Tract neurons (seven Dorsal Spinocerebellar Tract, three spinoreticular Tract), which exhibited a significant decrease in their spontaneous spike activity during active sleep, was examined. Glutamate-evoked activity in these cells was significantly attenuated during active sleep compared with wakefulness. In contrast, the glutamate-evoked activity of a second group of eight sensory Tract neurons (four Dorsal Spinocerebellar Tract, four spinoreticular Tract), which exhibited a significant increase in their spontaneous spike activity during active sleep, was not significantly altered in a state-dependent manner. These data indicate that, during natural active sleep, a dynamic neural process is engaged onto certain Dorsal Spinocerebellar Tract and spinoreticular Tract neurons, which in turn dampens sensory throughput to higher brain centers.
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Dorsal Spinocerebellar Tract neurons in the chronic intact cat during wakefulness and sleep: analysis of spontaneous spike activity
The Journal of neuroscience : the official journal of the Society for Neuroscience, 1996Co-Authors: Peter J. Soja, M C Fragoso, B E Cairns, Wg JiaAbstract:Relatively little is known about the transmission of ascending sensory information from lumbar levels across the behavioral states of sleep and wakefulness. The present study used extracellular recording methods in chronically instrumented intact behaving cats to monitor the activity of lumbar Dorsal Spinocerebellar Tract (DSCT) neurons within Clarke's column during the states of wakefulness, quiet sleep, and active sleep. Clarke's column DSCT neurons were identified using antidromic identification and retrograde labeling techniques. The spontaneous spike rate and interspike interval data of DSCT neurons were quantified as a function of behavioral state. During wakefulness and quiet sleep, the spike rate of DSCT neurons was stable, and interspike interval histograms (ISIH) indicated a relatively high degree of regularity in DSCT neuronal spike train patterns. In contrast, during active sleep there was a marked reduction in the ongoing spike rate in a vast majority of cells tested. The magnitude of change in ISIHs and interspike interval data during active sleep depended in part on whether the reduction in cell firing was maintained or periodic throughout active sleep. Further suppression of spontaneous activity also was observed during intense rapid-eye-movement episodes of active sleep that were associated with clustered pontogeniculo-occipital wave and muscular twitches and jerks. After re-awakening, spontaneous spike activity of Clarke's column DSCT neurons resembled that recorded during previous episodes of wakefulness. These data provide evidence that ascending proprioceptive and exteroceptive sensory transmission through Clarke's column is diminished during the behavioral state of active sleep.
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Dorsal Spinocerebellar Tract neuronal activity in the intact chronic cat.
Journal of neuroscience methods, 1995Co-Authors: Peter J. Soja, M C Fragoso, B E Cairns, J I OkaAbstract:The ability to electrophysiologically identify the axonal projections of lumbar neurons recorded in chronic unanesthetized intact awake animals is a formidable but essential requirement toward understanding ascending sensory transmission under naturally occurring conditions. Chronic immobilization procedures previously introduced by Morales et al. (1981) for intracellular studies of motoneurons are modified and then integrated with procedures for antidromic cellular identification and extracellular recording of upper (or lower) Dorsal lumbar Spinocerebellar Tract (DSCT) neuronal activity, in conjunction with behavioral state recording and drug microiontophoresis. These implant procedures provide up to 6 months of stable recording conditions and, when combined with other techniques, allow individual DSCT neurons to be monitored over multiple cycles of sleep and wakefulness, following the induction into and recovery from barbiturate anesthesia and/or during the juxtacellular microiontophoretic ejection of inhibitory or excitatory amino acid neurotransmitters. The combination of such techniques allows a comprehensive examination of synaptic transmission through the DSCT and other lumbar sensory pathways in the intact normally respiring cat and its modulation during the general anesthetic state. These techniques permit investigations of the supraspinal controls impinging on lumbar sensory Tract neurons during wakefulness and other behavioral states such as active sleep.
Shelly A. Mcerlane - One of the best experts on this subject based on the ideXlab platform.
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State-related inhibition by GABA and glycine of transmission in Clarke’s column
2013Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Peter J. SojaAbstract:During the state of active sleep (AS), Clarke’s column Dorsal Spinocerebellar Tract (DSCT) neurons undergo a marked reduction in their spontaneous and excitatory amino acid (EAA)evoked responses. The present study was performed to examine the magnitude, consistency of AS-specific suppression, and potential role of classical inhibitory amino acids GABA and glycine (GLY) in mediating this phenomenon. AS-specific suppression of DSCT neurons, expressed as the reduction in mean spontaneous firing rate during AS versus the preceding episode of wakefulness, was compared across three consecutive sleep cycles (SC), each consisting of wakefulness (W), AS, and awakening from AS (RW). Spontaneous spike rate did not differ during W or RW between SC1, SC2, and SC3. AS-specific suppression of spontaneous firing rate was found to be consistent and measured 40.3, 31.5, and 41.6 % in SC1
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State-dependent GABAergic inhibition of sciatic nerve-evoked responses of Dorsal Spinocerebellar Tract neurons.
Journal of neurophysiology, 2004Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Angela Chan, Sylvia Chow, Lizbeth Fabian, Peter J. SojaAbstract:Peripheral nerve-evoked potentials recorded in the cerebellum 35 yr ago inferred that sensory transmission via the Dorsal Spinocerebellar Tract (DSCT) is reduced occasionally and only during eye mo...
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On the reduction of spontaneous and glutamate-driven Spinocerebellar and spinoreticular Tract neuronal activity during active sleep.
Neuroscience, 2001Co-Authors: Peter J. Soja, Niwat Taepavarapruk, B E Cairns, Walton Pang, Shelly A. McerlaneAbstract:AbsTract The present study was performed to provide evidence that dynamic neural processes underlie the reduction in Dorsal Spinocerebellar Tract and spinoreticular Tract neuron activity that occurs during active sleep. To ascertain the effect of local inhibition on the spontaneous and glutamate-evoked spike discharge of sensory Tract neurons, preliminary control tests were performed during the state of quiet wakefulness, where GABA or glycine was co-administered in a sustained fashion during pulsatile release of glutamate to Dorsal Spinocerebellar Tract ( n =3) or spinoreticular Tract ( n =2) neurons. Co-administration of GABA or glycine also resulted in a significant marked suppression of spontaneous spike activity and glutamate-evoked responses of these cells. Extracellular recording experiments combined with juxtacellular application of glutamate were then performed on 20 antidromically identified Dorsal Spinocerebellar Tract and spinoreticular Tract neurons in the chronic intact cat as a function of sleep and wakefulness. The glutamate-evoked activity of a group of 10 sensory Tract neurons (seven Dorsal Spinocerebellar Tract, three spinoreticular Tract), which exhibited a significant decrease in their spontaneous spike activity during active sleep, was examined. Glutamate-evoked activity in these cells was significantly attenuated during active sleep compared with wakefulness. In contrast, the glutamate-evoked activity of a second group of eight sensory Tract neurons (four Dorsal Spinocerebellar Tract, four spinoreticular Tract), which exhibited a significant increase in their spontaneous spike activity during active sleep, was not significantly altered in a state-dependent manner. These data indicate that, during natural active sleep, a dynamic neural process is engaged onto certain Dorsal Spinocerebellar Tract and spinoreticular Tract neurons, which in turn dampens sensory throughput to higher brain centers.
Niwat Taepavarapruk - One of the best experts on this subject based on the ideXlab platform.
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State-related inhibition by GABA and glycine of transmission in Clarke’s column
2013Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Peter J. SojaAbstract:During the state of active sleep (AS), Clarke’s column Dorsal Spinocerebellar Tract (DSCT) neurons undergo a marked reduction in their spontaneous and excitatory amino acid (EAA)evoked responses. The present study was performed to examine the magnitude, consistency of AS-specific suppression, and potential role of classical inhibitory amino acids GABA and glycine (GLY) in mediating this phenomenon. AS-specific suppression of DSCT neurons, expressed as the reduction in mean spontaneous firing rate during AS versus the preceding episode of wakefulness, was compared across three consecutive sleep cycles (SC), each consisting of wakefulness (W), AS, and awakening from AS (RW). Spontaneous spike rate did not differ during W or RW between SC1, SC2, and SC3. AS-specific suppression of spontaneous firing rate was found to be consistent and measured 40.3, 31.5, and 41.6 % in SC1
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State-dependent GABAergic inhibition of sciatic nerve-evoked responses of Dorsal Spinocerebellar Tract neurons.
Journal of neurophysiology, 2004Co-Authors: Niwat Taepavarapruk, Shelly A. Mcerlane, Angela Chan, Sylvia Chow, Lizbeth Fabian, Peter J. SojaAbstract:Peripheral nerve-evoked potentials recorded in the cerebellum 35 yr ago inferred that sensory transmission via the Dorsal Spinocerebellar Tract (DSCT) is reduced occasionally and only during eye mo...
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On the reduction of spontaneous and glutamate-driven Spinocerebellar and spinoreticular Tract neuronal activity during active sleep.
Neuroscience, 2001Co-Authors: Peter J. Soja, Niwat Taepavarapruk, B E Cairns, Walton Pang, Shelly A. McerlaneAbstract:AbsTract The present study was performed to provide evidence that dynamic neural processes underlie the reduction in Dorsal Spinocerebellar Tract and spinoreticular Tract neuron activity that occurs during active sleep. To ascertain the effect of local inhibition on the spontaneous and glutamate-evoked spike discharge of sensory Tract neurons, preliminary control tests were performed during the state of quiet wakefulness, where GABA or glycine was co-administered in a sustained fashion during pulsatile release of glutamate to Dorsal Spinocerebellar Tract ( n =3) or spinoreticular Tract ( n =2) neurons. Co-administration of GABA or glycine also resulted in a significant marked suppression of spontaneous spike activity and glutamate-evoked responses of these cells. Extracellular recording experiments combined with juxtacellular application of glutamate were then performed on 20 antidromically identified Dorsal Spinocerebellar Tract and spinoreticular Tract neurons in the chronic intact cat as a function of sleep and wakefulness. The glutamate-evoked activity of a group of 10 sensory Tract neurons (seven Dorsal Spinocerebellar Tract, three spinoreticular Tract), which exhibited a significant decrease in their spontaneous spike activity during active sleep, was examined. Glutamate-evoked activity in these cells was significantly attenuated during active sleep compared with wakefulness. In contrast, the glutamate-evoked activity of a second group of eight sensory Tract neurons (four Dorsal Spinocerebellar Tract, four spinoreticular Tract), which exhibited a significant increase in their spontaneous spike activity during active sleep, was not significantly altered in a state-dependent manner. These data indicate that, during natural active sleep, a dynamic neural process is engaged onto certain Dorsal Spinocerebellar Tract and spinoreticular Tract neurons, which in turn dampens sensory throughput to higher brain centers.
B E Cairns - One of the best experts on this subject based on the ideXlab platform.
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On the reduction of spontaneous and glutamate-driven Spinocerebellar and spinoreticular Tract neuronal activity during active sleep.
Neuroscience, 2001Co-Authors: Peter J. Soja, Niwat Taepavarapruk, B E Cairns, Walton Pang, Shelly A. McerlaneAbstract:AbsTract The present study was performed to provide evidence that dynamic neural processes underlie the reduction in Dorsal Spinocerebellar Tract and spinoreticular Tract neuron activity that occurs during active sleep. To ascertain the effect of local inhibition on the spontaneous and glutamate-evoked spike discharge of sensory Tract neurons, preliminary control tests were performed during the state of quiet wakefulness, where GABA or glycine was co-administered in a sustained fashion during pulsatile release of glutamate to Dorsal Spinocerebellar Tract ( n =3) or spinoreticular Tract ( n =2) neurons. Co-administration of GABA or glycine also resulted in a significant marked suppression of spontaneous spike activity and glutamate-evoked responses of these cells. Extracellular recording experiments combined with juxtacellular application of glutamate were then performed on 20 antidromically identified Dorsal Spinocerebellar Tract and spinoreticular Tract neurons in the chronic intact cat as a function of sleep and wakefulness. The glutamate-evoked activity of a group of 10 sensory Tract neurons (seven Dorsal Spinocerebellar Tract, three spinoreticular Tract), which exhibited a significant decrease in their spontaneous spike activity during active sleep, was examined. Glutamate-evoked activity in these cells was significantly attenuated during active sleep compared with wakefulness. In contrast, the glutamate-evoked activity of a second group of eight sensory Tract neurons (four Dorsal Spinocerebellar Tract, four spinoreticular Tract), which exhibited a significant increase in their spontaneous spike activity during active sleep, was not significantly altered in a state-dependent manner. These data indicate that, during natural active sleep, a dynamic neural process is engaged onto certain Dorsal Spinocerebellar Tract and spinoreticular Tract neurons, which in turn dampens sensory throughput to higher brain centers.
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Dorsal Spinocerebellar Tract neurons in the chronic intact cat during wakefulness and sleep: analysis of spontaneous spike activity
The Journal of neuroscience : the official journal of the Society for Neuroscience, 1996Co-Authors: Peter J. Soja, M C Fragoso, B E Cairns, Wg JiaAbstract:Relatively little is known about the transmission of ascending sensory information from lumbar levels across the behavioral states of sleep and wakefulness. The present study used extracellular recording methods in chronically instrumented intact behaving cats to monitor the activity of lumbar Dorsal Spinocerebellar Tract (DSCT) neurons within Clarke's column during the states of wakefulness, quiet sleep, and active sleep. Clarke's column DSCT neurons were identified using antidromic identification and retrograde labeling techniques. The spontaneous spike rate and interspike interval data of DSCT neurons were quantified as a function of behavioral state. During wakefulness and quiet sleep, the spike rate of DSCT neurons was stable, and interspike interval histograms (ISIH) indicated a relatively high degree of regularity in DSCT neuronal spike train patterns. In contrast, during active sleep there was a marked reduction in the ongoing spike rate in a vast majority of cells tested. The magnitude of change in ISIHs and interspike interval data during active sleep depended in part on whether the reduction in cell firing was maintained or periodic throughout active sleep. Further suppression of spontaneous activity also was observed during intense rapid-eye-movement episodes of active sleep that were associated with clustered pontogeniculo-occipital wave and muscular twitches and jerks. After re-awakening, spontaneous spike activity of Clarke's column DSCT neurons resembled that recorded during previous episodes of wakefulness. These data provide evidence that ascending proprioceptive and exteroceptive sensory transmission through Clarke's column is diminished during the behavioral state of active sleep.
-
Dorsal Spinocerebellar Tract neuronal activity in the intact chronic cat.
Journal of neuroscience methods, 1995Co-Authors: Peter J. Soja, M C Fragoso, B E Cairns, J I OkaAbstract:The ability to electrophysiologically identify the axonal projections of lumbar neurons recorded in chronic unanesthetized intact awake animals is a formidable but essential requirement toward understanding ascending sensory transmission under naturally occurring conditions. Chronic immobilization procedures previously introduced by Morales et al. (1981) for intracellular studies of motoneurons are modified and then integrated with procedures for antidromic cellular identification and extracellular recording of upper (or lower) Dorsal lumbar Spinocerebellar Tract (DSCT) neuronal activity, in conjunction with behavioral state recording and drug microiontophoresis. These implant procedures provide up to 6 months of stable recording conditions and, when combined with other techniques, allow individual DSCT neurons to be monitored over multiple cycles of sleep and wakefulness, following the induction into and recovery from barbiturate anesthesia and/or during the juxtacellular microiontophoretic ejection of inhibitory or excitatory amino acid neurotransmitters. The combination of such techniques allows a comprehensive examination of synaptic transmission through the DSCT and other lumbar sensory pathways in the intact normally respiring cat and its modulation during the general anesthetic state. These techniques permit investigations of the supraspinal controls impinging on lumbar sensory Tract neurons during wakefulness and other behavioral states such as active sleep.