Simple spike modulation of Purkinje cells in the cerebellar nodulus of the pigmented rabbit to optokinetic stimulation

1. The cerebellar uvula-nodulus receives vestibular projections from primary and secondary vestibular afferents as well as vestibularly related climbing fibers. It also receives visually related information from climbing fiber pathways. In this experiment we investigated how this information is mapped onto the uvula-nodulus. We studied the specificity, dynamics, and topographic distribution of climbing fiber responses (CFRs), simple spike responses, and mossy fiber terminal responses evoked by vestibular and optokinetic stimulation in rabbits anesthetized with alpha-chloralose. 2. Vestibularly evoked CFRs were found in the ventral uvula and nodulus. These responses were evoked during static roll tilt of the rabbit about a longitudinal axis and by sinusoidal oscillation about the longitudinal axis. Purely static responses were attributed to stimulation of the utricular otolith by the linear acceleration of gravity. CFRs that lacked a static component were attributed to activation of the semicircular canals. 3. Using a "null technique" we showed that the canal-sensitive CFRs were caused by stimulation of the anterior or posterior semicircular canals. Of the CFRs classified as canal related, 96% could be attributed to stimulation of the vertical semicircular canals. 4. Increases in CFRs were correlated with decreases in simple spike responses in half the Purkinje cells from which we recorded. These climbing-fiber-induced pauses in simple spikes occurred during spontaneous climbing fiber discharge as well as during climbing fiber discharge evoked by vestibular stimulation. The duration of this pause was inversely proportional to the spontaneous level of simple spikes before the occurrence of a CFR. In the other half of the recorded population of Purkinje cells, vestibularly driven CFRs did not alter the simple spike responses. 5. Vestibularly and visually mediated CFRs were topographically represented on the surface of the uvula-nodulus. CFRs driven by ipsilateral otolithic inputs were distributed over the entire mediolateral surface of the uvula-nodulus. CFRs driven by the ipsilateral posterior semicircular canal were distributed in a sagittal strip approximately 1.5 mm wide, extending laterally from the midline of the nodulus. CFRs driven exclusively by horizontal, posterior-->anterior optokinetic stimulation of the ipsilateral eye were distributed in a sagittal strip approximately 0.5 mm wide located 0.5-1.0 mm from the midline and restricted to the ventral nodulus. CFRs driven by the ipsilateral anterior semicircular canal were found in a sagittal strip approximately 1.0 mm wide extending 1.0-2.0 mm from the midline. 6. The sagittal, topographically arrayed climbing fiber strips effectively map a mediolateral gradient of possible postural responses based on vestibular and optokinetic information.

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Direction selectivity of simple spike responses of Purkinje cells of the cerebellar flocculus of the pigmented rabbit to optokinetic stimulation

Neuroscience Research Supplements ◽

10.1016/0921-8696(90)90663-n ◽

1990 ◽

Vol 11 ◽

pp. S70

Author(s):

Masanobu Kano ◽

Misao Kano ◽

Kyoji Maekawa

Keyword(s):

Purkinje Cells ◽

Direction Selectivity ◽

Optokinetic Stimulation ◽

Simple Spike ◽

Cerebellar Flocculus

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Direction selectivity of simple spike responses of Purkinje cells of the cerebellar flocculus of the pigmented rabbit to optokinetic stimulation

Neuroscience Research Supplements ◽

10.1016/0921-8696(90)90240-4 ◽

1990 ◽

Vol 15 ◽

pp. S70

Author(s):

Masanobu Kano ◽

Misao Kano ◽

Kyoji Maekawa

Keyword(s):

Purkinje Cells ◽

Direction Selectivity ◽

Optokinetic Stimulation ◽

Simple Spike ◽

Cerebellar Flocculus

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Faculty Opinions recommendation of Predictive and feedback performance errors are signaled in the simple spike discharge of individual Purkinje cells.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717961781.793466066 ◽

2012 ◽

Author(s):

Julie Fiez

Keyword(s):

Purkinje Cells ◽

Spike Discharge ◽

Simple Spike ◽

Performance Errors

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Spatial organization of visual messages of the rabbit's cerebellar flocculus. II. Complex and simple spike responses of Purkinje cells

Journal of Neurophysiology ◽

10.1152/jn.1988.60.6.2091 ◽

1988 ◽

Vol 60 (6) ◽

pp. 2091-2121 ◽

Cited By ~ 198

Author(s):

W. Graf ◽

J. I. Simpson ◽

C. S. Leonard

Keyword(s):

Purkinje Cells ◽

Horizontal Plane ◽

Rotation Axis ◽

Modulation Depth ◽

Vertical Axis ◽

Axis Orientation ◽

Complex Spike ◽

Full Field ◽

Simple Spike ◽

Dominant Eye

1. Complex and simple spike responses of Purkinje cells were recorded in the flocculus of anesthetized, paralyzed rabbits during rotating full-field visual stimuli produced by a three-axis planetarium projector. 2. On the basis of the spatial properties of their complex spike responses, floccular Purkinje cells could be placed into three distinct classes called Vertical Axis, Anterior (45 degrees) Axis and Posterior (135 degrees) Axis. The first two classes occurred in both monocular and binocular forms; the third class was encountered only in binocular form. For the binocular response forms, stimulation through one eye, called the dominant eye, elicited a stronger modulation of the complex spike firing rate than did stimulation of the other eye. The approximate orientation of that axis about which full-field rotation elicited the deepest modulation (the preferred axis) when presented to the dominant eye served as the class label. These classes are the same as those determined qualitatively for inferior olive neurons in the previous paper (47). The present study provides a quantitative description of their spatial tuning. 3. For Vertical Axis cells, the dominant eye was ipsilateral with respect to the flocculus recording site. The preferred axis was vertical and null (no-response) axes were in the horizontal plane. For the binocular response form of Vertical Axis cells (less than 10% of this class), the direction preferences for the two eyes were synergistic with respect to rotation about the vertical axis. 4. The dominant eye for the Anterior (45 degrees) Axis cells was contralateral, with the preferred axis oriented in the horizontal plane at approximately 45 degrees contralateral azimuth. The modulation depth showed a close to cosine relation with the angle between the preferred axis and the stimulus rotation axis. The average orientation (n = 10) for the dominant eye preferred axis, determined by the best-fit sinusoid, was 47 degrees contralateral azimuth. The preferred axis orientation for the ipsilateral (nondominant) eye in the binocular response forms was between 45 and 90 degrees azimuth in the horizontal plane. A null axis for each eye was at approximately 90 degrees to the preferred axis. 5. The Posterior (135 degrees) Axis cells were encountered only in binocular response forms. The dominant eye was ipsilateral, with the preferred axis oriented at approximately 135 degrees ipsilateral azimuth close to the horizontal plane. The modulation depth showed a close to cosine relation with the angle between the preferred axis and the stimulus rotation axis.(ABSTRACT TRUNCATED AT 400 WORDS)

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Changes in the Responses of Purkinje Cells in the Floccular Complex of Monkeys After Motor Learning in Smooth Pursuit Eye Movements

Journal of Neurophysiology ◽

10.1152/jn.2000.84.6.2945 ◽

2000 ◽

Vol 84 (6) ◽

pp. 2945-2960 ◽

Cited By ~ 49

Author(s):

Maninder Kahlon ◽

Stephen G. Lisberger

Keyword(s):

Eye Movements ◽

Purkinje Cells ◽

Image Motion ◽

Population Response ◽

Complex Spike ◽

Pursuit Eye Movements ◽

Simple Spike ◽

Learning Speed ◽

Complex Spikes ◽

Spike Firing

We followed simple- and complex-spike firing of Purkinje cells (PCs) in the floccular complex of the cerebellum through learned modifications of the pursuit eye movements of two monkeys. Learning was induced by double steps of target speed in which initially stationary targets move at a “learning” speed for 100 ms and then change to either a higher or lower speed in the same direction. In randomly interleaved control trials, targets moved at the learning speed in the opposite direction. When the learning direction was theon direction for simple-spike responses, learning was associated with statistically significant changes in simple-spike firing for 10 of 32 PCs. Of the 10 PCs that showed significant expressions of learning, 8 showed changes in simple-spike output in the expected direction: increased or decreased firing when eye acceleration increased or decreased through learning. There were no statistically significant changes in simple-spike responses or eye acceleration during pursuit in the control direction. When the learning direction was in the off direction for simple-spike responses, none of 15 PCs showed significant correlates of learning. Although changes in simple-spike firing were recorded in only a subset of PCs, analysis of the population response showed that the same relationship between population firing and eye acceleration obtained before and after learning. Thus learning is associated with changes that render the modified population response appropriate to drive the changed behavior. To analyze complex-spike firing during learning we correlated complex-spike firing in the second, third, and fourth 100 ms after the onset of target motion with the retinal image motion in the previous 100 ms. Data were largely consistent with previous evidence that image motion drives complex spikes with a direction selectivity opposite that for simple spikes. Comparison of complex-spike responses at different times after the onset of control and learning target motions in the learning direction implied that complex spikes could guide learning during decreases but not increases in eye acceleration. Learning caused increases or decreases in the sensitivity of complex spikes to image motion in parallel with changes in eye acceleration. Complex-spike responses were similar in all PCs, including many in which learning did not modify simple-spike responses. Our data do not disprove current theories of cerebellar learning but suggest that these theories would have to be modified to account for simple- and complex-spike firing of floccular Purkinje cells reported here.

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Responses of cerebellar Purkinje cells to slip of a hand-held object

Journal of Neurophysiology ◽

10.1152/jn.1992.67.3.483 ◽

1992 ◽

Vol 67 (3) ◽

pp. 483-495 ◽

Cited By ~ 89

Author(s):

C. Dugas ◽

A. M. Smith

Keyword(s):

Receptive Field ◽

Purkinje Cells ◽

Cerebellar Cortex ◽

Grip Force ◽

Receptive Fields ◽

Emg Activity ◽

Spike Discharge ◽

Complex Spike ◽

Simple Spike ◽

Force Pulse

1. Two monkeys were trained to grasp, lift, and hold a device between the thumb and forefinger for 1 s. The device was equipped with a position transducer and strain gauges that measured the horizontal grip force and the vertical lifting or load force. On selected blocks of 20-30 trials, a force-pulse perturbation was applied to the object during static holding to simulate object slip. The animals were required to resist this displacement by stiffening the joints of their wrists and fingers to obtain a fruit juice reward. Single cells in the hand representation area of the paravermal anterior lobe of the cerebellar cortex were recorded during perturbed and unperturbed holding. If conditions permitted, the cell discharge was also recorded during lifting of objects of various weights (15, 65, or 115 g) or different surface textures (sandpaper or polished metal), and when possible the cutaneous or proprioceptive fields of the neurons were characterized with the use of natural stimulation. 2. On perturbed trials, the force pulse was always applied to the manipulandum after it had been held stationary within the position window for 750 ms. The perturbation invariably elicited a reflexlike increase of electromyographic (EMG) activity in wrist and finger muscles, resulting in a time-locked increase in grip force that peaked at a latency between 50 and 100 ms. 3. The object-slip perturbation had a powerful effect on cerebellar cortical neurons at a mean latency of 45 +/- 14 (SD) ms. Reflexlike increases or decreases in simple spike discharge occurred in 55% (53/97) of unidentified cells and 49% (21/43) of Purkinje cells recorded in the anterior paravermal and lateral cerebellar cortex. 4. The perturbation failed to evoke complex spike responses from any of the Purkinje cells examined. All the perturbation-evoked activity changes involved modulation of the simple spike discharge. The perturbations stimulated the simple-spike receptive field of most Purkinje cells recorded here, which suggests that the short-latency unit responses were triggered by afferent stimulation. Only one Purkinje cell was found with a distinct complex-spike receptive field on the thumb, but this neuron did not respond to the perturbation. It appears that simple- and complex-spike to receptive fields are not always identical or even closely related. 5. The majority of Purkinje and unidentified neurons that responded to the perturbation had cutaneous receptive fields, although some had proprioceptive fields. Seventy-seven neurons were examined for peripheral receptive fields and were also tested with the perturbation.(ABSTRACT TRUNCATED AT 400 WORDS)

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