A role for GABAergic inhibition in electrosensory processing and common mode rejection in the dorsal nucleus of the little skate, Raja erinacea

1996 ◽  
Vol 179 (6) ◽  
Author(s):  
C.H. Duman ◽  
D. Bodznick
Keyword(s):  
Gabaergic Inhibition ◽  
Raja Erinacea ◽  
Common Mode ◽  
Dorsal Nucleus ◽  
Electrosensory Processing

Motor corollary discharge activity and sensory responses related to ventilation in the skate vestibulolateral cerebellum: implications for electrosensory processing

1996 ◽  
Vol 199 (3) ◽  
pp. 673-681 ◽  
Author(s):  
G Hjelmstad ◽  
G Parks ◽  
D Bodznick
Keyword(s):  
Noise Cancellation ◽  
Second Order ◽  
Corollary Discharge ◽  
Parallel Fiber ◽  
Large Percentage ◽  
Principal Function ◽  
Raja Erinacea ◽  
Dorsal Nucleus ◽  
Sensory Responses ◽  
Electrosensory Processing

The dorsal granular ridge (DGR) of the elasmobranch vestibulolateral cerebellum is the source of a parallel fiber projection to the electrosensory dorsal nucleus. We report that the DGR in Raja erinacea contains a large percentage of units with activity modulated by the animal's own ventilation. These include propriosensory and electrosensory units, responding to either ventilatory movements or the resulting electroreceptive reafference, and an additional population of units in which activity is phase-locked to the ventilatory motor commands even in animals paralyzed to block all ventilatory movements. A principal function of processing in the dorsal nucleus is the elimination of ventilatory noise in second-order electrosensory neurons. The existence of these ventilatory motor corollary discharge units, along with other DGR units responsive to ventilatory movements, suggests that the parallel fiber projection is involved in the noise cancellation mechanisms.

The roles of GABAergic and glycinergic inhibition on binaural processing in the dorsal nucleus of the lateral lemniscus of the mustache bat

1994 ◽  
Vol 71 (6) ◽  
pp. 1999-2013 ◽  
Author(s):  
L. Yang ◽  
G. D. Pollak
Keyword(s):  
Tone Burst ◽  
Gabaergic Inhibition ◽  
Gamma Aminobutyric Acid ◽  
Lateral Lemniscus ◽  
Dorsal Nucleus ◽  
Iontophoretic Application ◽  
Monaural Stimulation ◽  
Contralateral Ear ◽  
Glycinergic Inhibition ◽  
Stimulation Of

1. We studied the monaural and binaural response properties of 99 neurons in the dorsal nucleus of the lateral lemniscus (DNLL) of the mustache bat before and during the iontophoretic application of antagonists that blocked gamma-aminobutyric acid-A (GABAA) receptors (bicuculline) or glycine receptors (strychnine). All cells were driven by monaural stimulation of the contralateral ear, whereas monaural stimulation of the ipsilateral ear never evoked discharges. The binaural properties of 81 neurons were determined by holding the intensity constant at the contralateral ear and presenting a variety of intensities to the ipsilateral ear. This procedure generated interaural intensity disparity (IID) functions and allowed us to determine the effect of ipsilaterally evoked inhibition on a constant excitatory drive evoked by the contralateral ear. 2. One of the main findings is that the IID functions in the majority of DNLL neurons were not affected by application of either strychnine or bicuculline. Blocking glycinergic inhibition with strychnine had no effect on the IID functions in 75% of the cells studied. However, strychnine did change the IID functions in approximately 25% of the DNLL population. In those cells glycinergic inhibition appeared to be partially, or, in a few cases, entirely responsible for the ipsilaterally evoked spike suppression. In contrast, blocking GABAergic inhibition with bicuculline had no discernible effect on the ipsilaterally evoked spike suppression in any of the excitatory/inhibitory cells that we recorded. GABAergic inhibition, therefore, plays no role in the formation of IID functions of neurons in the DNLL. Furthermore, the results suggest that glycinergic inhibition also does not contribute to the suppression of spikes evoked by stimulation of the contralateral ear in the vast majority of DNLL neurons. 3. Although the majority of IID functions were not influenced when either GABAergic or glycinergic innervation was blocked, ipsilateral stimulation alone evoked both a glycinergic and GABAergic inhibition in most DNLL cells. These inhibitory events were demonstrated in 18 other cells by evoking discharges with the iontophoretic application of glutamate. Stimulating the ipsilateral ear alone under these conditions caused a suppression of the glutamate-evoked discharges. Furthermore, the spike suppression persisted for a period of time that was longer than the duration of the tone burst at the ipsilateral ear. 4. The application of bicuculline or strychnine had different effects on the glutamate-elicited spikes. Bicuculline reduced the duration of the inhibition, and it was always the latter portion of the inhibition that was abolished by bicuculline. In more than half of the cells studied strychnine also reduced the duration of the inhibition.(ABSTRACT TRUNCATED AT 400 WORDS)

Differential Response Properties to Amplitude Modulated Signals in the Dorsal Nucleus of the Lateral Lemniscus of the Mustache Bat and the Roles of GABAergic Inhibition

1997 ◽  
Vol 77 (1) ◽  
pp. 324-340 ◽  
Author(s):  
Lichuan Yang ◽  
George D. Pollak
Keyword(s):  
Phase Locking ◽  
Modulation Frequency ◽  
Tone Burst ◽  
Differential Response ◽  
Gabaergic Inhibition ◽  
Lateral Lemniscus ◽  
Response Properties ◽  
Dorsal Nucleus ◽  
Modulated Signals ◽  
Onset Response

Yang, Lichuan and George D. Pollak. Differential response properties to amplitude modulated signals in the dorsal nucleus of the lateral lemniscus of the mustache bat and the roles of GABAergic inhibition. J. Neurophysiol. 77: 324–340, 1997. We studied the phase-locking of 89 neurons in the dorsal nucleus of the lateral lemniscus (DNLL) of the mustache bat to sinusoidally amplitude modulated (SAM) signals and the influence that GABAergic inhibition had on their response properties. Response properties were determined with tone bursts at each neuron's best frequency and then with a series of SAM signals that had modulation frequencies ranging from 50–100 to 800 Hz in 100-Hz steps. DNLL neurons were divided into two principal types: sustained neurons (55%), which responded throughout the duration of the tone burst, and onset neurons (45%), which responded only at the beginning of the tone burst. Sustained and onset neurons responded differently to SAM signals. Sustained neurons responded with phase-locked discharges to modulation frequencies ≤400–800 Hz. In contrast, 70% of the onset neurons phase-locked only to low modulation frequencies of 100–300 Hz, whereas 30% of the onset neurons did not phase-lock to any modulation frequency. Signal intensity differentially affected the phase-locking of sustained and onset neurons. Sustained neurons exhibited tight phase-locking only at low intensities, 10–30 dB above threshold. Onset neurons, in contrast, maintained strong phase-locking even at relatively high intensities. Blocking GABAergic inhibition with bicuculline had different effects on the phase-locking of sustained and onset neurons. In sustained neurons, there was an overall decline in phase-locking at all modulation frequencies. In contrast, 70% of the onset neurons phase-locked to much higher modulation frequencies than they did when inhibition was intact. The other 30% of onset neurons phase-locked to SAM signals, although they fired only with an onset response to the same signals before inhibition was blocked. In both cases, blocking GABAergic inhibition transformed their responses to SAM signals into patterns that were more like those of sustained neurons. We also propose mechanisms that could explain the differential effects of GABAergic inhibition on onset neurons that locked to low modulation frequencies and on onset neurons that did not lock to any SAM signals before inhibition was blocked. The key features of the proposed mechanisms are the absolute latencies and temporal synchrony of the excitatory and inhibitory inputs.

scholarly journals Suppression of Common Mode Signals Within the Electrosensory System of the Little Skate Raja Erinacea

1992 ◽  
Vol 171 (1) ◽  
pp. 107-125 ◽  
Author(s):  
DAVID BODZNICK ◽  
JOHN C. MONTGOMERY ◽  
DAVID J. BRADLEY
Keyword(s):  
Electric Fields ◽  
Sea Water ◽  
Raja Erinacea ◽  
Common Mode ◽  
Mode Suppression ◽  
The Common ◽  
Opening And Closing ◽  
Ion Pumping ◽  
Self Stimulation ◽  
Sinusoidal Currents

The electroreceptors of elasmobranchs are strongly modulated by the fish's own ventilation but this source of potential interference is suppressed within the medulla. The mechanism for the suppression is thought to be based on the common mode nature of the ventilatory noise, i.e. it is of the same amplitude and phase for all of the electroreceptors, compared with environmental electric fields which affect the receptors differentially. Evidence for the common mode suppression hypothesis is provided here in skates by the observation that the response to an artificial common mode stimulus that is independent of ventilation and delivered through an electrode inserted into the animal's gut is also suppressed by the medullary neurons; the extent to which a particular neuron suppresses the responses to the gut stimulus and to ventilation is similar. In addition, a potential modulation of 5–150μV is measured between the skate's interior and the sea water during ventilation and this appears to be responsible for the self-stimulation. By passing d.c. or sinusoidal currents through the gut electrode it is demonstrated that this ventilatory potential is due to the variable shunting of a standing d.c. potential across the fish's skin by the opening and closing of the mouth and gill slits during ventilation. Osmoregulatory ion-pumping appears to contribute to the production of the d.c. potential. Note: Present address: Department of Biology, Wesleyan University, Middletown, CT 06457, USA. Present address: Department of Zoology, University of Auckland, Auckland, New Zealand.

GABA and glycine have different effects on monaural response properties in the dorsal nucleus of the lateral lemniscus of the mustache bat

1994 ◽  
Vol 71 (6) ◽  
pp. 2014-2024 ◽  
Author(s):  
L. Yang ◽  
G. D. Pollak
Keyword(s):  
Tone Burst ◽  
Discharge Pattern ◽  
Gabaergic Inhibition ◽  
Response Properties ◽  
Dorsal Nucleus ◽  
Rate Intensity ◽  
Contralateral Ear ◽  
Discharge Patterns ◽  
Intensity Functions ◽  
Stimulation Of

1. We studied the monaural response properties of 81 neurons in the dorsal nucleus of the lateral lemniscus (DNLL) of the mustache bat before and during the iontophoretic application of antagonists that blocked gamma-aminobutyric acid-A (GABAA) receptors (bicuculline) or glycine receptors (strychnine). The main finding is that GABAergic inhibition had substantial effects, whereas glycine had little or no effect on the activity evoked by contralateral stimulation. 2. Before the application of drugs, the monaural response properties of DNLL cells were characterized by two main features. The first was that the majority (86%) of neurons had monotonic rate-intensity functions, whereas only 14% had weakly nonmonotonic functions. The second was that most (66%) neurons displayed some form of chopping response pattern, in which there was a regular interval between discharges that was unrelated to the period of the tone burst frequency. 3. Bicuculline had two major effects on the majority of DNLL cells. It caused large increases in spike counts and changes in temporal discharge patterns. In 38 of 47 cells (81%) bicuculline changed the temporal discharge patterns into a sustained chopper pattern. In addition, the duration of the discharge train continued for a period of time longer than the duration of the tone burst in many but not all neurons. Prolonged firing of this sort was rarely seen in the predrug condition. Furthermore, in a few cells bicuculline caused a decrease in the interspike interval as well as a lengthening of the discharge train. 4. Blocking glycine, in contrast, caused either small increases in spike count or no increase at all and did not affect the temporal discharge patterns in the majority (87%) of neurons. 5. In most DNLL cells the shapes of the rate-intensity functions were virtually the same before and during the application of either antagonist. The rate-intensity functions of 91% of the cells were unaffected by bicuculline and 98% were unaffected by strychnine. 6. Blocking either GABAergic inhibition or glycinergic inhibition had no effect on discharge latency in the vast majority of DNLL cells. In a few neurons application of bicuculline or strychnine had a small influence and caused discharge latency to decrease by < or = 1 ms. 7. These results show that the excitation from stimulation of the contralateral ear evokes a sustained chopping discharge pattern in the vast majority of DNLL neurons. The sustained chopping response is changed into another discharge pattern by the GABAergic innervation that is also evoked by stimulation of the contralateral ear.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals HINDBRAIN CIRCUITRY MEDIATING COMMON MODE SUPPRESSION OF VENTILATORY REAFFERENCE IN THE ELECTROSENSORY SYSTEM OF THE LITTLE SKATE RAJA ERINACEA

1993 ◽  
Vol 183 (1) ◽  
pp. 203-216 ◽  
Author(s):  
J. C. Montgomery ◽  
D. Bodznick
Keyword(s):  
Receptive Field ◽  
Receptive Fields ◽  
Afferent Input ◽  
Raja Erinacea ◽  
Common Mode ◽  
Electrosensory System ◽  
Mode Suppression ◽  
Basal Dendrites ◽  
Elasmobranch Fish ◽  
Rejection Mechanism

Elasmobranch fish have an electrosensory system which they use for prey detection and for orientation. Sensory inputs to this system are corrupted by a form of reafference generated by the animal's own ventilation, but this noise is reduced by sensory processing within the medullary nucleus of the electrosensory system. This noise cancellation is achieved, at least in part, by a common mode rejection mechanism. In this study we have examined characteristics of neurones within the medullary nucleus in an attempt to understand the neural circuitry responsible for common mode suppression. Our results are in accord with previous indications that ascending efferent neurones of the medullary nucleus are monosynaptically activated from the ipsilateral electrosensory nerves and project to the midbrain. We demonstrate that in Raja erinacea, as has been previously shown in one other species (Cephaloscyllium isabella), ascending efferent neurones typically have a discrete focal excitatory receptive field and an inhibitory receptive field which may be discrete or diffuse and which often includes a contralateral component. We identify a group of interneurones within the medullary nucleus which are driven monosynaptically from the electrosensory nerves, have simple discrete excitatory receptive fields and respond vigorously to imposed common mode signals. The simplest model of the circuitry underlying common mode rejection that is consistent with the evidence is that direct afferent input impinges onto the basal dendrites of the ascending efferent neurones and onto interneurones within the nucleus, and the interneurones in turn inhibit the ascending efferents. The pattern of this projection, including commissural inputs, determines the nature and extent of ascending efferents' inhibitory surrounds and mediates the suppression of common mode signals.

The Unique Contribution of Positive Orientation to Optimal Functioning

2012 ◽  
Vol 17 (1) ◽  
pp. 44-54 ◽  
Author(s):  
Guido Alessandri ◽  
Gian Vittorio Caprara ◽  
John Tisak
Keyword(s):  
Psychological Functioning ◽  
Well Being ◽  
Unique Contribution ◽  
Critical Component ◽  
Positive Orientation ◽  
Cross Sectional ◽  
Common Mode ◽  
Optimal Functioning

Literature documents that the judgments people hold about themselves, their life, and their future are important ingredients of their psychological functioning and well-being, and are commonly related to each other. In this paper, results from a large cross-sectional sample (N = 1,331, 48% males) are presented attesting to the hypothesis that evaluations about oneself, one’s life, and one’s future rest on a common mode of viewing experiences named “Positive Orientation.” These results corroborate the utility of the new construct as a critical component of individuals’ well functioning.

Common-mode Noise Reduction Circuit Design for Biosignal Acquisition System—in Comparison with the DRL

2019 ◽  
Vol 139 (12) ◽  
pp. 657-662
Author(s):  
Minghui Chen ◽  
Jianqing Wang ◽  
Daisuke Anzai ◽  
Georg Fischer
Keyword(s):  
Noise Reduction ◽  
Circuit Design ◽  
Acquisition System ◽  
Common Mode
Sign in / Sign up

Export Citation Format

Share Document