Review: The Biological Basis of
Audition
Recanzone and Sutter
Presented by Joseph Schilz
Outline
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Introduction
Organization of Audition
Auditory Spatial Processing
Interactions with visual stimuli
Ventriloquism effect
Ventriloquism after-effect
Auditory Temporal Processing
Temporal integration
Forward masking
Gap detection
Introduction
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Audition and vision major sensory systems
Audition does not have the significant history
of research that vision does
Differences between audition and vision
Tasks in decoding audition:
Where a sound came from
Spectral properties
Temporal properties
Identifying what sound represents
Review's focus: location and temporal
properties
Organization of Audition
Fig 1. Recanzone and Sutter
Organization of Audition
Fig 2.
Recanzone & Sutter
Organization of Audition
Tonotopy
Fig 2. Kalatsky et al.
Organization of Audition
Tonal Tuning
Fig 2:
Bitterman et al.
Organization of Audition
Tonal/Spatial Tuning
Fig 2.
Bizley & King
Organization of Audition
“What” and “Where” Paths?
Fig 1: Design
Ahveninen et al.
Organization of Audition
“What” and “Where” Paths?
Fig 2: Results
Ahveninen et al.
Auditory Spatial Processing
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Cues
Interactions with visual stimuli
Ventriloquism effect
Ventriloquism after-effect
Auditory Spatial Processing
Cues
Fig 3. Recanzone and Sutter
Auditory Spatial Processing
Cues
Fig 1. Yu and Young
Auditory Spatial Processing
Ventriloquism effect
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Definition
Cognitive factors
“unity assumption”
Non-cognitive factors
Timing
Compellingness
Spatial discrepancy/agreement
Auditory Spatial Processing
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Ventriloquism effect
Early studies assumed that the more precise
modality would “capture” the less precise
modality.
Later studies showed a near optimal “mixing”
of modality reports, respecting the measureerror variance of each modality.
Auditory Spatial Processing
Ventriloquism effect
Fig 2: Design and Results
Kording et al.
Auditory Spatial Processing
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Ventriloquism after-effect
If subject is presented with audio/visual
stimuli of a consistent spatial disparity,
subjects spatial perception of acoustic space
shifted after
Long lasting
Does not transfer across frequencies
Different from other adaption illusions: lasts
tens of minutes, does not transfer across
frequencies, in the same direction of
adapting stimulus.
Auditory Spatial Processing
Ventriloquism after-effect
Fig 4: Design and Results
Recanzone
Auditory Spatial Processing
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Ventriloquism after-effect
Difficulty of single unit recording in illusions.
Direct projection from auditory to visual
(observed in primates)
Direct projection from visual to auditory
(observed in ferrets)
Several areas in brain with multisensory
response
Ghanzafar study
Auditory Temporal Processing
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Definition
Temporal integration
Forward masking
Gap detection
Auditory Temporal Processing
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Definition
Can mean processing of temporal aspects of
stimuli or ability of neurons to encode
stimulus by temporal aspects of firing
We refer to former
Temporal processing could be interpreted to
include spectral processing
We don't consider spectral processing here
Auditory Temporal Processing
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Temporal integration
Our environments are noisy; audition might
wait a bit and let noise average itself out
before passing on a percept
On the other hand, some decisions need to
be made quickly; audition shouldn't hold onto
information for too long
How to assess? At what levels is this
occurring?
Auditory Temporal Processing
Temporal integration
Fig 4. Dallos and Olsen
Auditory Temporal Processing
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Temporal integration
Varies with loudness, frequency, duration
Bloch's Law (Loudness x Duration = k)
Leaky integrator model
Mean integration times of 30-40msec in
humans
Auditory Temporal Processing
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Temporal integration
Clock et al. found similar constants of
integration in chinchilla cochlear nucleus
neurons and chinchilla behavior
Exponential leaky integrator fit model well
But, auditory nerve neurons had time
constants much larger
Explanation
Auditory Temporal Processing
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Forward masking
Two sounds presented sequentially, with
some gap, sometimes subject will not
perceive second sound.
Depends on many factors
Generally measured as a
function of first sound's duration.
Fig 4. Recanzone and Sutter
Auditory Temporal Processing
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Forward masking
Likely a result of adaptation.
Auditory Temporal Processing
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Gap detection
Temporal resolution vs. temporal integration
One paradigm for temporal resolution: gap
detection
Humans able to detect gaps in noise as small
as 1-2msec
Auditory nerve firing shows gaping pattern
Likely some role of cortex in detecting gaps,
as shown by lesion, deactivation studies
Auditory Temporal Processing
Gap detection
Fig 2. Zhang et al.
Additional Works Referenced
Ahveninen et al. Task-modulated “what” and “where” pathways in human auditory
cortex PNAS 2006 103 (39) 14608-14613; published ahead of print September 18,
2006, doi:10.1073/pnas.0510480103
Y. Bitterman, R. Mukamel, R. Malach, I. Fried, & I. Nelken Ultra-fine frequency
tuning revealed in single neurons of human auditory cortex Nature 451, 197-201 (10
January 2008)
Jennifer K. Bizley, Andrew J. King, Visual-auditory spatial processing in auditory
cortical neurons, Brain Research, Volume 1242, Multisensory Integration, 25
November 2008, Pages 24-36, ISSN 0006-8993, DOI:
10.1016/j.brainres.2008.02.087.
P. Dallos, W. Olsen, Integration of energy at threshold with gradual rise-fall tone
pips. Journal of the Acoustical Soc. of America.Vol. 36, pp. 743-751, April 1964
V Kalatsky, D Polley, M Merzenich, C Schreiner, Mstryker, Fine functional
organization of auditory cortex revealed by Fourier optical imaging PNAS 2005 102
(37) 13325-13330; published ahead of print September 1, 2005,
doi:10.1073/pnas.0505592102
Additional Works Referenced
Kording KP, Beierholm U, Ma WJ, Quartz S, Tenenbaum JB, et al (2007) Causal
Inference in Multisensory Perception. PLoS ONE 2(9): e943.
doi:10.1371/journal.pone.0000943
Recanzone G, Rapidly induced auditory plasticity: The ventriloquism aftereffect.
Proc. Natl. Acad. Sci. USA Vol. 95, pp. 869–875, February 1998
J Yu, E Young, Linear and nonlinear pathways of spectral information transmission
in the cochlear nucleus PNAS 2000 97 (22) 11780-11786
W. Zhang, R.J. Salvi, S.S. Saunders, Neural correlates of gap detection in auditory
nerve fibers of the chinchilla, Hearing Research, Volume 46, Issue 3, July 1990,
Pages 181-200, ISSN 0378-5955, DOI: 10.1016/0378-5955(90)90001-6.