Auditory neurons must represent accurately a wide range of sound levels using firing rates that vary over far narrower levels. Recently, we demonstrated this "dynamic problem" is lessened by neural adaptation, whereby adjust their input–output functions for level according to the prevailing distribution These adjustments in increase accuracy with which around those occurring most commonly are coded population. Here, examine how quickly adaptation occurs. We recorded from single auditory...

Neural adaptation is central to sensation. Neurons in auditory midbrain, for example, rapidly adapt their firing rates enhance coding precision of common sound intensities. However, it remains unknown whether this fixed, or dynamic and dependent on experience. Here, using guinea pigs as animal models, we report that accelerates when an environment re-encountered-in response a repeatedly switches between quiet loud, midbrain neurons accrue experience find efficient code more rapidly. This...

Good metrics of the performance a statistical or computational model are essential for comparison and selection. Here, we address design models that aim to predict neural responses sensory inputs. This is particularly difficult because neurons inherently variable, even in response repeated presentations identical stimuli. In this situation, standard (such as correlation coefficient) fail they do not distinguish between explainable variance (the part systematically dependent on stimulus)...

One of the key problems brain faces is inferring state world from a sequence dynamically changing stimuli, and it not yet clear how sensory system achieves this task. A well-established computational framework for describing perceptual processes in provided by theory predictive coding. Although original proposals coding have discussed temporal prediction, later work developing mostly focused on static questions neural implementation properties networks remain open. Here, we address these...

Periodic stimuli are common in natural environments and ecologically relevant, for example, footsteps vocalizations. This study reports a detectability enhancement temporally cued, periodic sequences. Target noise bursts (embedded background noise) arriving at the time points which followed on from an introductory, “cue” sequence were more easily detected (by ∼1.5 dB SNR) than identical randomly deviated cued temporal pattern. Temporal predictability corresponding neuronal “entrainment” have...

Cortical sensory neurons are commonly characterized using the receptive field, linear dependence of their response on stimulus. In primary auditory cortex can be by spectrotemporal fields, spectral and temporal features a sound that linearly drive neuron. However, fields do not capture fact cortical neuron results from complex nonlinear network in which it is embedded. By fitting feedforward model (a field) to responses natural sounds, we reveal sensitive over substantially larger domain...

Neurons in sensory cortex are tuned to diverse features natural scenes. But what determines which neurons become selective to? Here we explore the idea that neuronal selectivity is optimized represent recent past best predict immediate future inputs. We tested this hypothesis using simple feedforward neural networks, were trained next few moments of video or audio clips The networks developed receptive fields closely matched those real cortical different mammalian species, including oriented...

Non-invasive recordings of gross neural activity in humans often show responses to omitted stimuli steady trains identical stimuli. This has been taken as evidence for the coding prediction or error. However, such omission from invasive cellular-scale animal models is scarce. Here, we sought characterise using extracellular auditory cortex anaesthetised rats. We profiled across local field potentials (LFP), analogue multiunit (AMUA), and single/multi-unit spiking activity, that were...

We present a device that combines principles of ultrasonic echolocation and spatial hearing to provide human users with environmental cues are 1) not otherwise available the auditory system, 2) richer in object information than more heavily processed sonar other assistive devices. The consists wearable headset an emitter stereo microphones affixed artificial pinnae. goal this study is describe evaluate utility echoic it provides.

Adaptation to stimulus statistics, such as the mean level and contrast of recently heard sounds, has been demonstrated at various levels auditory pathway. It allows nervous system operate over wide range intensities contrasts found in natural world. Yet current standard models response properties neurons do not incorporate adaptation. Here we present a model neural responses ferret cortex (the IC model), which takes into account adaptation sound lower processing: inferior colliculus (IC)....

The ability to spontaneously feel a beat in music is phenomenon widely believed be unique humans. Though perception involves the coordinated engagement of sensory, motor and cognitive processes humans, contribution low-level auditory processing activation these networks beat-specific manner poorly understood. Here, we present evidence from rodent model that midbrain preprocessing sounds may already shaping where ultimately felt. For tested set musical rhythms, on-beat on average evoked...

Significance Sensory systems are extremely complex, with diverse neurons and connections. However, this does not necessarily imply that the computations performed by these also as complex. Here we examine impact of processing in ear subcortical pathway on neural responses to natural sounds auditory cortex. We find can be described more consistently using simple spectral models. This suggests there may an underlying simplicity signal transformation from cortex is hidden among detail. a...

Visual neurons respond selectively to features that become increasingly complex from the eyes cortex. Retinal prefer flashing spots of light, primary visual cortical (V1) moving bars, and those in higher areas favor like textures. Previously, we showed V1 simple cell tuning can be accounted for by a basic model implementing temporal prediction – representing predict future sensory input past (Singer et al., 2018). Here, show hierarchical application capture how properties change across at...

Sound texture perception takes advantage of a hierarchy time-averaged statistical features acoustic stimuli, but much remains unclear about how these are processed along the auditory pathway. Here, we compared neural representation sound textures in inferior colliculus (IC) and cortex (AC) anesthetized female rats. We recorded responses to morph stimuli that gradually add increasingly higher complexity. For each texture, several different exemplars were synthesized using random seeds. An...

Abstract The retina’s role in visual processing has been viewed as two extremes: an efficient compressor of incoming stimuli akin to a camera, or predictor future stimuli. Addressing this dichotomy, we developed biologically-detailed spiking retinal model trained on natural movies under metabolic-like constraints either encode the present predict scenes. Our findings reveal that when optimized for prediction ∼ 100 ms into future, not only captures retina-like receptive fields and their...

A major cue to the location of a sound source is interaural time difference (ITD)-the in arrival at two ears. The neural representation this auditory unresolved. classic model ITD coding, dominant for half-century, posits that distribution best ITDs (the evoking neuron's maximal response) unimodal and largely within range permitted by head-size. This often interpreted as place code location. An alternative model, based on neurophysiology small mammals, bimodal with exquisite sensitivity...

This study investigates the influence of temporal regularity on human listeners' ability to detect a repeating noise pattern embedded in statistically identical non-repeating noise. Human listeners were presented with white stimuli that either contained frozen segment repeated temporally regular or irregular manner, did not contain any repetition at all. Subjects instructed respond as soon they detected stimulus. Pattern detection performance was best when targets occurred suggesting plays...

Many neurons adapt their spike output to accommodate the prevailing sensory environment. Although such adaptation is thought improve coding of relevant stimulus features, relationship between at neural and behavioral levels remains be established. Here we describe improved discrimination performance for an auditory spatial cue (interaural time differences, ITDs) following statistics. Physiological recordings in midbrain anesthetized guinea pigs measurement humans both demonstrate most...

Previous research has shown that musical beat perception is a surprisingly complex phenomenon involving widespread neural coordination across higher-order sensory, motor and cognitive areas. However, the question of how low-level auditory processing must necessarily shape these dynamics, therefore perception, not well understood. Here, we present evidence cortical representation music, even in absence or top-down activations, already favours will be perceived. Extracellular firing rates rat...

In almost every natural environment, sounds are reflected by nearby objects, producing many delayed and distorted copies of the original sound, known as reverberation. Our brains usually cope well with reverberation, allowing us to recognize sound sources regardless their environments. contrast, reverberation can cause severe difficulties for speech recognition algorithms hearing-impaired people. The present study examines how auditory system copes We trained a linear model recover rich set...

Abstract One of the key problems brain faces is inferring state world from a sequence dynamically changing stimuli, and it not yet clear how sensory system achieves this task. A well-established computational framework for describing perceptual processes in provided by theory predictive coding. Although original proposals coding have discussed temporal prediction, later work developing mostly focused on static questions neural implementation properties networks remain open. Here, we address...

Auditory neurons encode stimulus history, which is often modelled using a span of time-delays in spectro-temporal receptive field (STRF). We propose an alternative model for the encoding we apply to extracellular recordings primary auditory cortex anaesthetized ferrets. For linear-non-linear STRF (LN model) achieve high level performance predicting single unit neural responses natural sounds cortex, found that it necessary include time delays going back at least 200 ms past. This unrealistic...