scholarly journals An early gain-control mechanism in binocular combination

2010 ◽  
Vol 6 (6) ◽  
pp. 832-832 ◽  
Author(s):  
G. Sperling ◽  
J. Ding
2005 ◽  
Vol 93 (1) ◽  
pp. 201-209 ◽  
Author(s):  
Marcel van der Heijden ◽  
Philip X. Joris

The nonlinear cochlear phenomenon of two-tone suppression is known to be very fast, but precisely how fast is unknown. We studied the timing of low-side suppression in the auditory nerve of the cat using multitone complexes as auditory stimuli. An evalution of the group delays of the responses to these complexes allowed us to measure the timing of the responses with sub-millisecond accuracy for a large number of fibers with characteristic frequencies (CFs) between 2 and 40 kHz. In particular, we measured the delays with which the same below-CF tone complexes affected the response either as an excitor (when presented alone) or as a suppressor (when combined with a CF probe). For CFs <10 kHz, we found that the delay of suppression was larger than the delay of excitation by several hundred microseconds. The difference between the delay of suppression and that of excitation decreased with increasing CF, becoming negligible for CFs >15 kHz. The results are analyzed in terms of traveling-wave delays and a purported cochlear gain control. The data suggest that suppression originates from a gain-control mechanism with an integration time in the order of two cycles of CF.


Neuron ◽  
2008 ◽  
Vol 59 (2) ◽  
pp. 311-321 ◽  
Author(s):  
Cory M. Root ◽  
Kaoru Masuyama ◽  
David S. Green ◽  
Lina E. Enell ◽  
Dick R. Nässel ◽  
...  

1998 ◽  
Vol 38 (13) ◽  
pp. 1925-1933 ◽  
Author(s):  
Lawrence G Brown ◽  
Michael E Rudd

1972 ◽  
Vol 60 (6) ◽  
pp. 698-719 ◽  
Author(s):  
John E. Dowling ◽  
Harris Ripps

Receptor potentials were recorded extracellularly from the all-rod retina of the skate after the application of sodium aspartate. This agent suppresses the responses of proximal elements, but leaves relatively unaffected the electrical activity of the photoreceptors (a-wave) and pigment epithelium (c-wave). Since the latter develops too slowly to interfere with the receptor response, it was possible to isolate receptor potentials and to compare their behavior in light and dark adaptation with earlier observations on the S-potential, b-wave, and ganglion cell discharge. The results show that the photoreceptors display the full complement of adaptational changes exhibited by cells proximal to the receptors. Thus, it appears that visual adaptation in the skate is governed primarily by the photoreceptors themselves. Of particular interest was the recovery of sensitivity in the presence of background fields that initially saturate the receptor potential. Analysis of this recovery phase indicates that a gain-control mechanism operates within the receptors, at a distal stage of the visual process.


2019 ◽  
Author(s):  
Daniel Yon ◽  
Vanessa Zainzinger ◽  
Floris de Lange ◽  
Martin Eimer ◽  
Clare Press

We predict how our actions will influence the world around us. Prevailing models of action control propose that we use these predictions to suppress or ‘cancel’ perception of expected action outcomes. However, contrasting normative Bayesian models in sensory cognition suggest that top-down predictions bias observers toward perceiving what they expect. Here we adjudicated between these models by investigating how expectations influence perceptual decisions about briefly presented action outcomes. Contrary to dominant cancellation models, we found that observers’ perceptual decisions are biased toward the presence of outcomes congruent with their actions. Computational modelling revealed this action-induced bias reflected a bias in how sensory evidence was accumulated, rather than a baseline shift in decision circuits. In combination, these results reveal a gain control mechanism that can explain how we generate largely veridical representations of our actions and their consequences in an inherently uncertain sensory world.


2017 ◽  
Vol 312 (2) ◽  
pp. R172-R188 ◽  
Author(s):  
Rishi R. Dhingra ◽  
Mathias Dutschmann ◽  
Roberto F. Galán ◽  
Thomas E. Dick

Respiration varies from breath to breath. On the millisecond timescale of spiking, neuronal circuits exhibit variability due to the stochastic properties of ion channels and synapses. Does this fast, microscopic source of variability contribute to the slower, macroscopic variability of the respiratory period? To address this question, we modeled a stochastic oscillator with forcing; then, we tested its predictions experimentally for the respiratory rhythm generated by the in situ perfused preparation during vagal nerve stimulation (VNS). Our simulations identified a relationship among the gain of the input, entrainment strength, and rhythm variability. Specifically, at high gain, the periodic input entrained the oscillator and reduced variability, whereas at low gain, the noise interacted with the input, causing events known as “phase slips”, which increased variability on a slow timescale. Experimentally, the in situ preparation behaved like the low-gain model: VNS entrained respiration but exhibited phase slips that increased rhythm variability. Next, we used bilateral muscimol microinjections in discrete respiratory compartments to identify areas involved in VNS gain control. Suppression of activity in the nucleus tractus solitarii occluded both entrainment and amplification of rhythm variability by VNS, confirming that these effects were due to the activation of the Hering-Breuer reflex. Suppressing activity of the Kölliker-Fuse nuclei (KFn) enhanced entrainment and reduced rhythm variability during VNS, consistent with the predictions of the high-gain model. Together, the model and experiments suggest that the KFn regulates respiratory rhythm variability via a gain control mechanism.


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