scholarly journals Stellate cell computational modeling predicts signal filtering in the molecular layer circuit of cerebellum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Martina Francesca Rizza ◽  
Francesca Locatelli ◽  
Stefano Masoli ◽  
Diana Sánchez-Ponce ◽  
Alberto Muñoz ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Stellate Cell ◽  
Molecular Layer ◽  
Stellate Cells ◽  
Parallel Fiber ◽  
Cell Discharge ◽  
Physiological Properties ◽  
Low Pass ◽  
Band Pass ◽  
Very High Frequencies

AbstractThe functional properties of cerebellar stellate cells and the way they regulate molecular layer activity are still unclear. We have measured stellate cells electroresponsiveness and their activation by parallel fiber bursts. Stellate cells showed intrinsic pacemaking, along with characteristic responses to depolarization and hyperpolarization, and showed a marked short-term facilitation during repetitive parallel fiber transmission. Spikes were emitted after a lag and only at high frequency, making stellate cells to operate as delay-high-pass filters. A detailed computational model summarizing these physiological properties allowed to explore different functional configurations of the parallel fiber—stellate cell—Purkinje cell circuit. Simulations showed that, following parallel fiber stimulation, Purkinje cells almost linearly increased their response with input frequency, but such an increase was inhibited by stellate cells, which leveled the Purkinje cell gain curve to its 4 Hz value. When reciprocal inhibitory connections between stellate cells were activated, the control of stellate cells over Purkinje cell discharge was maintained only at very high frequencies. These simulations thus predict a new role for stellate cells, which could endow the molecular layer with low-pass and band-pass filtering properties regulating Purkinje cell gain and, along with this, also burst delay and the burst-pause responses pattern.

scholarly journals Stellate cell computational modelling predicts signal filtering in the molecular layer circuit of cerebellum

2020 ◽  
Author(s):  
Martina Francesca Rizza ◽  
Francesca Locatelli ◽  
Stefano Masoli ◽  
Diana Sánchez Ponce ◽  
Alberto Muñoz ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Stellate Cell ◽  
Molecular Layer ◽  
Computational Modelling ◽  
Stellate Cells ◽  
Parallel Fiber ◽  
Cell Discharge ◽  
Physiological Properties ◽  
Low Pass ◽  
Very High Frequencies

AbstractThe functional properties of cerebellar stellate cells and the way they regulate molecular layer activity are still unclear. We have measured stellate cells electroresponsiveness and their activation by parallel fiber bursts. Stellate cells showed intrinsic pacemaking, along with characteristic responses to depolarization and hyperpolarization, and showed a marked short-term facilitation during repetitive parallel fiber transmission. Spikes were emitted after a lag and only at high frequency, making stellate cells to operate as delay-high-pass filters. A detailed computational model summarizing these physiological properties allowed to explore different functional configurations of the parallel fiber – stellate cell – Purkinje cell circuit. Simulations showed that, following parallel fiber stimulation, Purkinje cells almost linearly increased their response with input frequency but such an increase was inhibited by stellate cells, which leveled the Purkinje cell gain curve to its 4 Hz value. When reciprocal inhibitory connections between stellate cells were activated, the control of stellate cells over Purkinje cell discharge was maintained only at very high frequencies. These simulations thus predict a new role for stellate cells, which could endow the molecular layer with low-pass and band-pass filtering properties regulating Purkinje cell gain and, along with this, also burst delay and the burst-pause responses pattern.

Distal Versus Proximal Inhibitory Shaping of Feedback Excitation in the Electrosensory Lateral Line Lobe: Implications for Sensory Filtering

1998 ◽  
Vol 80 (6) ◽  
pp. 3214-3232 ◽  
Author(s):  
Neil J. Berman ◽  
Leonard Maler
Keyword(s):  
Lateral Line ◽  
Pyramidal Cell ◽  
Stellate Cell ◽  
Molecular Layer ◽  
Pyramidal Cells ◽  
Stellate Cells ◽  
Decay Phase ◽  
Tetanic Stimulation ◽  
Parallel Fibers ◽  
Cell Inhibition

Berman, Neil J. and Leonard Maler. Distal versus proximal inhibitory shaping of feedback excitation in the electrosensory lateral line lobe: implications for sensory filtering. J. Neurophysiol. 80: 3214–3232, 1998. The inhibition controlling the indirect descending feedback (parallel fibers originating from cerebellar granule cells in the eminentia posterior pars granularis) to electrosensory lateral line lobe (ELL) pyramidal cells was studied using intracellular recording techniques in vitro. Parallel fibers (PF) contact stellate cells and dendrites of ventral molecular layer (VML) GABAergic interneurons. Stellate cells provide local input to pyramidal cell distal dendrites, whereas VML cells contact their somata and proximal dendrites. Single-pulse stimulation of PF evoked graded excitatory postsynaptic potentials (EPSPs) that were blocked by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and N-methyl-d-aspartate (NMDA) antagonists. The EPSPs peaked at 6.4 ± 1.8 ms (mean ± SE; n = 11) but took >50 ms to decay completely. Tetanic stimulation (100 ms, 100 Hz) produced a depolarizing wave with individual EPSPs superimposed. The absolute amplitude of the individual EPSPs decreased during the train. Spike rates, established by injected current, mostly were increased, but in some cells were decreased, by tetanic stimulation. Global application of a γ-aminobutyric acid-A (GABAA) antagonist to the recorded cell's soma and apical dendritic region increased the EPSP peak and decay phase amplitudes. Tetanic stimulation always increased current-evoked spike rates after GABAA blockade during, and for several hundred milliseconds after, the stimulus. Application of a GABAB antagonist did not have any significant effects on the PF-evoked response. This, and the lack of any long hyperpolarizing inhibitory postsynaptic potentials, suggests that VML and stellate cell inhibition does not involve GABAB receptors. Focal GABAA antagonist applications to the dorsal molecular layer (DML) and pyramidal cell layer (PCL) had contrasting effects on PF-evoked EPSPs. DML GABAA blockade significantly increased the EPSP peak amplitude but not the decay phase of the EPSP, whereas PCL GABAA-blockade significantly increased the decay phase, but not the EPSP peak, amplitude. The order of antagonist application did not affect the outcome. On the basis of the known circuitry of the ELL, we conclude that the distal inhibition originated from GABAergic molecular layer stellate cells and the proximal inhibition originated from GABAergic cells of the ventral molecular layer (VML cells). Computer modeling of distal and proximal inhibition suggests that intrinsic differences in IPSP dynamics between the distal and proximal sites may be amplified by voltage-dependent NMDA receptor and persistent sodium currents. We propose that the different time courses of stellate cell and VML cell inhibition allows them to act as low- and high-pass filters respectively on indirect descending feedback to ELL pyramidal cells.

scholarly journals Impact of parallel fiber to Purkinje cell long-term depression is unmasked in absence of inhibitory input

2018 ◽  
Vol 4 (10) ◽  
pp. eaas9426 ◽  
Author(s):  
Henk-Jan Boele ◽  
Saša Peter ◽  
Michiel M. Ten Brinke ◽  
Lucas Verdonschot ◽  
Anna C. H. IJpelaar ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Eyeblink Conditioning ◽  
Molecular Layer ◽  
Learning Task ◽  
Parallel Fiber ◽  
Neural Mechanisms ◽  
Inhibitory Input ◽  
Long Term Depression ◽  
Feed Forward Inhibition

Pavlovian eyeblink conditioning has been used extensively to study the neural mechanisms underlying associative and motor learning. During this simple learning task, memory formation takes place at Purkinje cells in defined areas of the cerebellar cortex, which acquire a strong temporary suppression of their activity during conditioning. Yet, it is unknown which neuronal plasticity mechanisms mediate this suppression. Two potential mechanisms include long-term depression of parallel fiber to Purkinje cell synapses and feed-forward inhibition by molecular layer interneurons. We show, using a triple transgenic approach, that only concurrent disruption of both these suppression mechanisms can severely impair conditioning, highlighting that both processes can compensate for each other’s deficits.

scholarly journals Modulated discharge of Purkinje and stellate cells persists after unilateral loss of vestibular primary afferent mossy fibers in mice

2013 ◽  
Vol 110 (10) ◽  
pp. 2257-2274 ◽  
Author(s):  
N. H. Barmack ◽  
V. Yakhnitsa
Keyword(s):  
Purkinje Cells ◽  
Stellate Cell ◽  
Mossy Fibers ◽  
Stellate Cells ◽  
Climbing Fibers ◽  
Afferent Pathways ◽  
Parallel Fibers ◽  
Primary Afferent ◽  
Low Frequencies ◽  
Cell Discharge

Cerebellar Purkinje cells are excited by two afferent pathways: climbing and mossy fibers. Climbing fibers evoke large “complex spikes” (CSs) that discharge at low frequencies. Mossy fibers synapse on granule cells whose parallel fibers excite Purkinje cells and may contribute to the genesis of “simple spikes” (SSs). Both afferent systems convey vestibular information to folia 9c–10. After making a unilateral labyrinthectomy (UL) in mice, we tested how the discharge of CSs and SSs was changed by the loss of primary vestibular afferent mossy fibers during sinusoidal roll tilt. We recorded from cells identified by juxtacellular neurobiotin labeling. The UL preferentially reduced vestibular modulation of CSs and SSs in folia 8–10 contralateral to the UL. The effects of a UL on Purkinje cell discharge were similar in folia 9c–10, to which vestibular primary afferents project, and in folia 8–9a, to which they do not project, suggesting that vestibular primary afferent mossy fibers were not responsible for the UL-induced alteration of SS discharge. UL also induced reduced vestibular modulation of stellate cell discharge contralateral to the UL. We attribute the decreased modulation to reduced vestibular modulation of climbing fibers. In summary, climbing fibers modulate CSs directly and SSs indirectly through activation of stellate cells. Whereas vestibular primary afferent mossy fibers cannot account for the modulated discharge of SSs or stellate cells, the nonspecific excitation of Purkinje cells by parallel fibers may set an operating point about which the discharges of SSs are sculpted by climbing fibers.

Turtle hippocampal cortex contains distinct cell types, burst-firing neurons, and an epileptogenic subfield

1986 ◽  
Vol 56 (6) ◽  
pp. 1626-1649 ◽  
Author(s):  
J. M. Shen ◽  
A. R. Kriegstein
Keyword(s):  
Cortical Neurons ◽  
Lucifer Yellow ◽  
Molecular Layer ◽  
Pyramidal Cells ◽  
Stellate Cells ◽  
Cortical Region ◽  
Synaptic Response ◽  
Frequency Adaptation ◽  
Medial Cortex ◽  
Physiological Properties

The dorsal and medial telencephalon of reptiles consists of a simple trilaminar cortex. The turtle dorsal cortex has been identified as a favorable physiological preparation that may bear a phylogenetic relationship to mammalian neocortex. While anatomical studies have likened the reptilian medial cortical region to mammalian hippocampus, its physiological properties have not been explored. We therefore used intracellular and extracellular recording techniques to examine the cellular and synaptic physiology of turtle "hippocampal" or medial cortex. Turtle medial cortex contains two principal classes of neurons, pyramidal cells and stellate neurons. Recordings with Lucifer yellow CH (LY)-filled microelectrodes allowed us to correlate the physiological properties of medial cortical neurons with their cellular morphology. Pyramidal neurons were situated in a single cellular layer and had spiny apical dendrites extending into the molecular layer. These cells fired relatively long-duration action potentials (APs) and showed frequency adaptation to suprathreshold current pulse injections. Stellate cells were usually found in the subcellular and molecular layers and had aspiny dendrites. In contrast to pyramidal cells, they fired brief APs and displayed no frequency adaptation. A discrete population of cells in the dorsal portion of medial cortex (DMC) was capable of bursting endogenously or in response to synaptic activation. Bursts usually contained an underlying slow depolarization and often occurred at regular intervals. Intracellular LY injections confirmed that these cells were pyramidal in morphology. Electrical stimulation of afferent fibers revealed that pyramidal cells and stellate neurons differed in their synaptic responses. In ventral medial cortex (VMC), afferent stimulation evoked a multiphasic response in most pyramidal cells, whereas stellate cells were synaptically excited. Orthodromic activation of DMC bursting cells resulted in a powerful excitation--often a short burst--and subsequent inhibition. Stellate neurons in DMC also had a biphasic synaptic response consisting of both an early excitation and a late inhibition. Experiments using intracellular chloride (Cl-) injection or focal bicuculline application suggested that part of the inhibitory component of the pyramidal cell synaptic response was dependent on a gamma-aminobutyric acid (GABA)-mediated increase in Cl- conductance. These results correlated with our immunohistochemical studies that revealed the presence of GABAergic neurons in medial cortex.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Molecular layer interneurons shape the spike activity of cerebellar Purkinje cells

2018 ◽  
Author(s):  
Amanda M. Brown ◽  
Marife Arancillo ◽  
Tao Lin ◽  
Daniel R. Catt ◽  
Joy Zhou ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Purkinje Cells ◽  
Stellate Cell ◽  
Molecular Layer ◽  
Complex Spike ◽  
Gabaergic Neurotransmission ◽  
Simple Spike ◽  
Firing Properties ◽  
Spike Firing

One-sentence summaryCerebellar stellate cells and basket cells shape distinct Purkinje cell firing propertiesAbstractPurkinje cells receive synaptic input from several classes of interneurons. Here, we address the roles of inhibitory molecular layer interneurons in establishing Purkinje cell function in vivo. Using conditional genetics approaches in mice, we compare how the lack of stellate cell versus basket cell GABAergic neurotransmission sculpts the firing properties of Purkinje cells. We take advantage of an inducible Ascl1CreER allele to spatially and temporally target the deletion of the vesicular GABA transporter, Vgat, in developing neurons. Selective depletion of basket cell GABAergic neurotransmission increases the frequency of Purkinje cell simple spike firing and decreases the frequency of complex spike firing in adult behaving mice. In contrast, lack of stellate cell communication increases the regularity of Purkinje cell simple spike firing while increasing the frequency of complex spike firing. Our data uncover complementary roles for molecular layer interneurons in shaping the rate and pattern of Purkinje cell activity in vivo.

Amplitude Distributions of Cochlear Microphonic Response to an Acoustic Sinusoid in Noise

1968 ◽  
Vol 11 (1) ◽  
pp. 63-76
Author(s):  
Donald C. Teas ◽  
Gretchen B. Henry
Keyword(s):  
Small Amplitude ◽  
Basilar Membrane ◽  
Spectral Composition ◽  
Pass Band ◽  
Cochlear Microphonic ◽  
Filter Output ◽  
Electronic Filter ◽  
Low Pass ◽  
Band Pass ◽  
Instantaneous Voltage

The distributions of instantaneous voltage amplitudes in the cochlear microphonic response recorded from a small segment along the basilar membrane are described by computing amplitude histograms. Comparisons are made between the distributions for noise and for those after the addition to the noise of successively stronger sinusoids. The amplitudes of the cochlear microphonic response to 5000 Hz low-pass noise are normally distributed in both Turn I and Turn III of the guinea pig’s cochlea. The spectral composition of the microphonic from Turn I and from Turn III resembles the output of band-pass filters set at about 4000 Hz, and about 500 Hz, respectively. The normal distribution of cochlear microphonic amplitudes for noise is systematically altered by increasing the strength of the added sinusoid. A decrease of three percent in the number of small amplitude events (±1 standard deviation) in the cochlear microphonic from Turn III is seen when the rms voltage of a 500 Hz sinusoid is at −18 dB re the rms voltage of the noise (at the earphone). When the rms of the sinusoid and noise are equal, the decrease in small voltages is about 25%, but there is also an increase in the number of large voltage amplitudes. Histograms were also computed for the output of an electronic filter with a pass-band similar to Turn III of the cochlea. Strong 500 Hz sinusoids showed a greater proportion of large amplitudes in the filter output than in CM III . The data are interpreted in terms of an anatomical substrate.

Realization of Enhanced LMS Filter Using Carry Skip Adder And Quantum Dot Cellular Automation In VLSI For Removing Impulse Noises In Medical Image

2019 ◽  
Vol 14 ◽  
Author(s):  
K.R. Shankarkumar ◽  
Gokul Kumar
Keyword(s):  
Adaptive Filtering ◽  
Adaptive Filters ◽  
Pass Band ◽  
Least Mean Square ◽  
Low Pass ◽  
Parallel Prefix ◽  
Loop Feedback ◽  
Band Pass ◽  
The Difference ◽  
Prefix Adder

: Filtering is an important step in the field of image processing to suppress the required parts or to remove any artifacts present in it. There are different types of filters like low pass, high pass, Band pass, IIR, FIR and adaptive filtering etc.., in these filters adaptive filters is an important filter because it is used to remove the noisy signal and images. Least Mean Square filter is a type of an adaptive filtering which is used to remove the noises present in the medical images. The working of LMS is based on the minimization of the difference between the error images using a closed loop feedback. Therefore presented technique called as Q-CSKA. Here the CSKA performs its operation in stages which is based on the nucleus stage. In the traditional CSKA the nucleus stage is depend on the parallel prefix adder in this work it is replaced by the QCA adder. The QCA adder utilizes the less area compared to PPA and it can be realized in Nanometer range also. For multiplexers, And OR Invert, OR and Invert logic is used to reduce the area and delay. Due to these advantages of the QCA, AOI-OAI logic the proposed method outperformed the LMS implementation in area, power, and accuracy and delay, this based five type image noise of medical pictures related to the best technique is out comes. It helps to medicinal practitioner to resolve the symptoms of patient with ease.

Regularity and latency of units in ventral cochlear nucleus: implications for unit classification and generation of response properties

1988 ◽  
Vol 60 (1) ◽  
pp. 1-29 ◽  
Author(s):  
E. D. Young ◽  
J. M. Robert ◽  
W. P. Shofner
Keyword(s):  
Standard Deviation ◽  
Cochlear Nucleus ◽  
Interspike Interval ◽  
Rate Adaptation ◽  
Stellate Cells ◽  
Instantaneous Rate ◽  
Ventral Cochlear Nucleus ◽  
Bushy Cell ◽  
Low Pass ◽  
The Mean

1. The responses of neurons in the ventral cochlear nucleus (VCN) of decerebrate cats are described with regard to their regularity of discharge and latency. Regularity is measured by estimating the mean and standard deviation of interspike intervals as a function of time during responses to short tone bursts (25 ms). This method extends the usual interspike-interval analysis based on interval histograms by allowing the study of temporal changes in regularity during transient responses. The coefficient of variation (CV), equal to the ratio of standard deviation to mean interspike interval, is used as a measure of irregularity. Latency is measured as the mean and standard deviation of the latency of the first spike in response to short tone bursts, with 1.6-ms rise times. 2. The regularity and latency properties of the usual PST histogram response types are shown. Five major PST response type classes are used: chopper, primary-like, onset, onset-C, and unusual. The presence of a prepotential in a unit's action potentials is also noted; a prepotential implies that the unit is recorded from a bushy cell. 3. Units with chopper PST histograms give the most regular discharge. Three varieties of choppers are found. Chop-S units (regular choppers) have CVs less than 0.35 that are approximately constant during the response; chop-S units show no adaptation of instantaneous rate, as measured by the inverse of the mean interspike interval. Chop-T units have CVs greater than 0.35, show an increase in irregularity during the response and show substantial rate adaptation. Chop-U units have CVs greater than 0.35, show a decrease in irregularity during the response, and show a variety of rate adaptation behaviors, including negative adaptation (an increase in rate during a short-tone response). Irregular choppers (chop-T and chop-U units) rarely have CVs greater than 0.5. Choppers have the longest latencies of VCN units; all three groups have mean latencies at least 1 ms longer than the shortest auditory nerve (AN) fiber mean latencies. 4. Chopper units are recorded from stellate cells in VCN (35, 42). Our results for chopper units suggest a model for stellate cells in which a regularly firing action potential generator is driven by the summation of the AN inputs to the cell, where the summation is low-pass filtered by the membrane capacitance of the cell.(ABSTRACT TRUNCATED AT 400 WORDS)

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