Simulating biological neuronal networks is a core method of research in computational neuroscience. A full specification such network model includes description the dynamics and state changes neurons synapses, as well synaptic connectivity patterns initial values all parameters. standard approach modelling software to build models based on library pre-defined mechanisms; if component does not yet exist, it has be defined special-purpose or general low-level language potentially compiled...

The activity of sensory neural populations carries information about the environment. This may be extracted from using different strategies. In auditory brainstem, a recent theory proposes that sound location in horizontal plane is decoded relative summed two each hemisphere, whereas earlier theories hypothesized was identity most active cells. We tested performance various decoders responses increasingly complex acoustical situations, including spectrum variations, noise, and diffraction....

Interaural time difference (ITD) is a major cue to sound localization in humans and animals. For given subject position space, ITD depends on frequency. This variation analyzed here using head related transfer functions (HRTFs) database collected from the literature comprising human HRTFs 130 subjects animal six specimens of different species. humans, found vary with frequency way that shows consistent differences respect spherical model. Maximal values were be about 800 μs low frequencies...

The binaural interaction component (BIC) of the auditory brainstem response is a noninvasive electroencephalographic signature neural processing sounds. Despite its potential as clinical biomarker, structures and mechanism that generate BIC are not known. We explore here hypothesis emerges from excitatory–inhibitory interactions in neurons. measured to click stimuli while varying interaural time differences (ITDs) subjects either sex five animal species. Species had head sizes spanning...

Hypothesis: Intracochlear pressures (P IC ) and stapes velocity (V stap elicited by bilaterally placed bone-anchored hearing devices (BAHD) will be systematically modulated imposed interaural time (ITD) level differences (ILD), demonstrating the potential for users of bilateral BAHD to access these binaural cues. Background: are traditionally implanted unilaterally under assumption that transcranial cross-talk limits differences. Recent studies have demonstrated improvements in spatial...

The time it takes a sound to travel from source ear differs between the ears and creates an interaural delay. It varies systematically with spatial direction is generally modeled as pure delay, independent of frequency. In acoustical recordings, we found that delay frequency at fine scale. physiological recordings midbrain neurons sensitive preferred also Similar observations reported earlier were not incorporated in functional framework. We find dependence delays are matched key respects....

The human cochlea includes about 3000 inner hair cells which filter sounds at frequencies between 20 Hz and kHz. This massively parallel frequency analysis is reflected in models of auditory processing, are often based on banks filters. However, existing implementations do not exploit this parallelism. Here we propose algorithms to simulate these by vectorizing computation over channels, implemented "Brian Hears," a library for the spiking neural network simulator package "Brian." approach...

Brian 2 is a fundamental rewrite of the [1,2] simulator for spiking neural networks. written in Python programming language and focuses on simplicity extensibility: neuronal models can be described using mathematical formulae (differential equations) with use physical units. Depending model equations, several integration methods are available, ranging from exact linear differential equations to numerical arbitrarily complex equations. The same formalism also used specify synaptic models,...

The binaural interaction component (BIC) is the residual auditory brainstem response (ABR) obtained after subtracting sum of monaurally evoked from binaurally ABRs. DN1 peak-the first negative peak BIC-has been postulated to have diagnostic value as a biomarker for hearing abilities. Indeed, not only do amplitudes depend systematically upon cues location (interaural time and level differences), but they are also predictive central deficits in humans. A prominent issue using BIC measures that...

A challenge for sensory systems is to encode natural signals that vary in amplitude by orders of magnitude. The spike trains neurons the auditory system must represent fine temporal structure sounds despite a tremendous variation sound level environments. It has been shown vitro transformation from dynamic into precise can be accurately captured simple integrate-and-fire models. In this work, we show vivo responses cochlear nucleus bushy cells across wide range levels precisely predicted...

A common way to assess the function of sensory neurons is measure number spikes produced by individual while systematically varying a given dimension stimulus. Such measured tuning curves can then be used quantify accuracy neural representation stimulus under study, which in turn related behavioral performance. However, often change shape when other dimensions are varied, reflecting simultaneous sensitivity multiple features. Here we illustrate how one-dimensional information analyses...

Abstract Early sensory experience can exert lasting perceptual consequences. For example, a brief period of auditory deprivation early in life lead to persistent spatial hearing deficits. Some forms loss (i.e., conductive; CHL) distort acoustical cues needed for hearing, which depend on inputs from both ears. We hypothesize that asymmetric acoustic input during development disrupts circuits integrate binaural information. Here, we identify prolonged maturation the brainstem guinea pig by...

Acoustic stimulation generates measurable sound pressure levels in the semicircular canals.High-intensity acoustic stimuli can cause hearing loss and balance disruptions. To examine propagation of to vestibular end-organs, we simultaneously measured fluid cochlea canals during both air- bone-conducted presentation.Five full-cephalic human cadaveric heads were prepared bilaterally with a mastoidectomy extended facial recess. Vestibular pressures within superior, lateral, posterior canals,...

Reliable animal head-related transfer function (HRTF) estimation procedures are needed for several practical applications, example, to investigate the neuronal mechanisms of sound localization using virtual acoustic spaces or have a quantitative description different cues available given species. Here, two established techniques combined estimate an animal's HRTF from photographs by taking into account as much morphological detail possible. The first step method consists in building...

Simulated otitis media with effusion reduces intracochlear pressures comparable to umbo velocity.Otitis is a common cause of temporary hearing loss, particularly in children, producing deficits 30 40 dB. Previous studies measured the effects simulated on ossicular mechanics; however, no have cochlear stimulation directly. Here, we compare scala vestibuli and tympani velocity, before after induction cadaveric human specimens.Eight cadaveric, hemi-cephalic heads were prepared complete...

Retrospective case series observational study.Cancer patients are often aged and further weakened by their illness treatments. Our goal was to evaluate the efficiency safety of using minimally invasive techniques operate on spinal fractures in these patients.Vertebroplasty is now considered be a safe technique that allows significant reduction pain induced tumoral fracture. However, few papers describe kyphosis can achieved combining percutaneous fixation anterior vertebral reconstruction.We...

In many species, azimuthal sound source localization relies on the processing of fine temporal differences between incoming signals at both ears (interaural time differences, ITDs). There exists no consensual theory ITD-based that explains behavioral and neural data alike. The classical view a place code for [1] is questioned by electrophysiological [2], while its alternative functionally inefficient [3]. We propose as functional principle system performs maximum-likelihood estimation...

Objectives (1) To characterize changes in brainstem neural activity following unilateral deafening an animal model. (2) compare from unilaterally deafened animals with that of normal‐hearing controls. Study Design Prospective controlled study. Setting Vivarium and research facilities. Subjects Methods The effect single‐sided deafness on was studied Chinchilla lanigera . Animals were via gentamycin injection into the middle ear, which verified by loss auditory responses (ABRs). underwent...

To localize sounds in the environment, animals mostly use spectro-temporal cues originating from physical disparities of sound waveforms impacting ears. Among those, Interaural Time Difference (ITD) has been shown to be crucial mammals for locating low-frequency sounds, and is known processed by neurons a particular structure, Medial Superior Olive (MSO). While it classically considered that emergence ITD selectivity neuron MSO due differences axonal delays two ears impinging cell (the so...