Abstract
Adaptation of sensory neurons to the prevailing environment is thought to underlie improved coding of relevant stimulus features. Here, we report that neurons in the inferior colliculus (IC) of anesthetized guinea pigs adapt to statistical distributions of interaural time differences (ITDs - one of the binaural cues for sound-source localization). Each distribution contained all of the ITDs in the range of ±330 µs, but with a different high probability range (HPR) of ITDs in each from which ITDs were chosen 80% of the time. The center (mean) or the width (variance) of the HPR was altered systematically to assess the sensitivity of each neuron to the underlying distribution of ITDs. Neural rate-vs.-ITD functions shifted to accommodate the change in the underlying distribution when the mean of the HPR, but not the variance, was altered. Assuming a population of similarly tuned binaural neurons with Poisson spike statistics inputting to an IC neuron, we used an established model of synaptic depression to compute the IC postsynaptic current. By including a stochastic leaky integrate-and-fire mechanism in the IC spike generator, the model predicts the changes in neural gain and the shapes of rate-ITD functions as well as the shifts in Fisher information, a measure of coding accuracy, observed in the physiological data.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsReferences
Borisyuk A, Semple MN, Rinzel J (2002) Adaptation and inhibition underlie responses to time-varying interaural phase cues in a model of inferior colliculus neurons. J Neurophysiol 88:2134–2146
Cai H, Carney LH, Colburn HS (1998) A model for binaural response properties of inferior colliculus neurons. II. A model with interaural time difference-sensitive excitatory and inhibitory inputs and an adaptation mechanism. J Acoust Soc Am 103:494–506
Chechik G, Anderson MJ, Bar-Yosef O, Young ED, Tishby N, Nelken I (2006) Reduction of information redundancy in the ascending auditory pathway. Neuron 51:359–368
Dean I, Harper NS, McAlpine D (2005) Neural population coding of sound level adapts to stimulus statistics. Nat Neurosci 8:1684–1689
Fairhall AL, Lewen GD, Bialek W, de Ruyter van Steveninck RR (2001) Efficiency and ambiguity in an adaptive neural code. Nature 412:787–792
Ingham NJ, McAlpine D (2004) Spike-frequency adaptation in the inferior Colliculus. J Neurophysiol 91:635–645
Ohzawa I, Sclar G, Freeman RD (1982) Contrast gain control in the cat visual cortex. Nature 298:266–268
Popelář J, Nwabueze-Ogbo FC, Syka J (2003) Changes in neural activity of the inferior colliculus in rat after temporal inactivation of the auditory cortex. Physiol Res 52:615–628
Seshagiri CV, Delgutte B (2003) Simultaneous single-unit recording from local populations in the inferior colliculus. Assoc Res Otolaryngol (Abstract 1280)
Shackleton TM, Skottun BC, Arnott RH, Palmer AR (2003) Interaural time difference discrimination thresholds for single neurons in the inferior colliculus of guinea pigs. J Neurosci 23:716–724
Spitzer MW, Semple MN (1993) Responses of inferior colliculus neurons to time-varying interaural phase disparity: effects of shifting the locus of virtual motion. J Neurophysiol 69:1245–1263
Spitzer MW, Semple MN (1995) Neurons sensitive to interaural phase disparity in gerbil superior olive: diverse monaural and temporal response properties. J Neurophysiol 73:1668–1690
Sterbing SJ, Hartung K, Hoffmann KP (2003) Spatial tuning to virtual sounds in the inferior colliculus of the guinea pig. J Neurophysiol 90:2648–2659
Tsodyks M, Pawelzik K, Markram H (1998) Neural networks with dynamic synapses. Neural Comput 10:821–835
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2010 Springer Science+Business Media, LLC
About this paper
Cite this paper
Hehrmann, P., Maier, J.K., Harper, N.S., McAlpine, D., Sahani, M. (2010). Adaptive Coding for Auditory Spatial Cues. In: Lopez-Poveda, E., Palmer, A., Meddis, R. (eds) The Neurophysiological Bases of Auditory Perception. Springer, New York, NY. https://doi.org/10.1007/978-1-4419-5686-6_34
Download citation
DOI: https://doi.org/10.1007/978-1-4419-5686-6_34
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4419-5685-9
Online ISBN: 978-1-4419-5686-6
eBook Packages: Biomedical and Life SciencesBiomedical and Life Sciences (R0)