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Joris PX, Verschooten E. Midbrain sensitivity to auditory motion studied with dichotic sweeps of broadband noise. Hear Res 2024; 450:109066. [PMID: 38889563 DOI: 10.1016/j.heares.2024.109066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 05/18/2024] [Accepted: 06/02/2024] [Indexed: 06/20/2024]
Abstract
Many neurons in the central nucleus of the inferior colliculus (IC) show sensitivity to interaural time differences (ITDs), which is thought to be relayed from the brainstem. However, studies with interaural phase modulation of pure tones showed that IC neurons have a sensitivity to changes in ITD that is not present at the level of the brainstem. This sensitivity has been interpreted as a form of sensitivity to motion. A new type of stimulus is used here to study the sensitivity of IC neurons to dynamic changes in ITD, in which broad- or narrowband stimuli are swept through a range of ITDs with arbitrary start-ITD, end-ITD, speed, and direction. Extracellular recordings were obtained under barbiturate anesthesia in the cat. We applied the same analyses as previously introduced for the study of responses to tones. We find effects of motion which are similar to those described in response to interaural phase modulation of tones. The size of the effects strongly depended on the motion parameters but was overall smaller than reported for tones. We found that the effects of motion could largely be explained by the temporal response pattern of the neuron such as adaptation and build-up. Our data add to previous evidence questioning true coding of motion at the level of the IC.
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Affiliation(s)
- Philip X Joris
- Lab. of Auditory Neurophysiology, KU Leuven, Herestraat 49 B-3000 Leuven, Belgium; Dept. of Neuroscience, UW-Madison, 111 Highland Avenue, Madison, WI 53705-2275, USA.
| | - Eric Verschooten
- Lab. of Auditory Neurophysiology, KU Leuven, Herestraat 49 B-3000 Leuven, Belgium
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İlhan B, Kurt S, Ungan P. Auditory cortical responses to abrupt lateralization shifts do not reflect the activity of hemifield-specific units involved in opponent coding of auditory space. Neuropsychologia 2023; 188:108629. [PMID: 37356539 DOI: 10.1016/j.neuropsychologia.2023.108629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/20/2023] [Accepted: 06/22/2023] [Indexed: 06/27/2023]
Abstract
Recent studies show that the classical model based on axonal delay-lines may not explain interaural time difference (ITD) based spatial coding in humans. Instead, a population-code model called "opponent channels model" (OCM) has been suggested. This model comprises two competing channels respectively for the two auditory hemifields, each with a sigmoidal tuning curve. Event-related potentials (ERPs) to ITD-changes are used in some studies to test the predictions of this model by considering the sounds before and after the change as adaptor and probe stimuli, respectively. It is assumed in these studies that the former stimulus causes adaptation of the neurons selective to its side, and that the ERP N1-P2 response to the ITD-change is the specific response of the neurons with selectivity to the side of probe sound. However, these ERP components are known as a global, non-specific acoustic change complex of cortical origin evoked by any change in the auditory environment. It probably does not genuinely reflect the activity of some stimulus-specific neuronal units that have escaped the refractory effect of the preceding adaptor, which means a violation of the crucial assumption in an adaptor-probe paradigm. To assess this viewpoint, we conducted two experiments. In the first one, we recorded ERPs to abrupt lateralization shifts of click trains having various pre- and post-shift ITDs within the physiological range of -600μs to +600μs. Magnitudes of the ERP components P1, N1, and P2 to these ITD-shifts did not comply with the additive behavior of partial probe responses presumed for an adaptor-probe paradigm, casting doubt on the accuracy of testing sensory coding models by using ERPs to abrupt lateralization changes. Findings of the second experiment, involving ERPs to conjoint outwards/transverse shift stimuli also supported this conclusion.
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Affiliation(s)
- Barkın İlhan
- Department of Biophysics, Necmettin Erbakan University Meram Medical Faculty, Konya, Türkiye.
| | - Saliha Kurt
- Department of Audiometry, Selçuk University Vocational School of Health Services, Konya, Türkiye.
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Joris PX. Neural binaural sensitivity at high sound speeds: Single cell responses in cat midbrain to fast-changing interaural time differences of broadband sounds. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 145:EL45. [PMID: 30710960 PMCID: PMC7112706 DOI: 10.1121/1.5087524] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 12/13/2018] [Accepted: 12/18/2018] [Indexed: 06/09/2023]
Abstract
Relative motion between the body and the outside world is a rich source of information. Neural selectivity to motion is well-established in several sensory systems, but is controversial in hearing. This study examines neural sensitivity to changes in the instantaneous interaural time difference of sounds at the two ears. Midbrain neurons track such changes up to extremely high speeds, show only a coarse dependence of firing rate on speed, and lack directional selectivity. These results argue against the presence of selectivity to auditory motion at the level of the midbrain, but reveal an acuity which enables coding of fast-fluctuating binaural cues in realistic sound environments.
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Affiliation(s)
- Philip X Joris
- Laboratory of Auditory Neurophysiology, KU Leuven, Herestraat 49, B-3000 Leuven, Belgium
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Sound frequency affects the auditory motion-onset response in humans. Exp Brain Res 2018; 236:2713-2726. [PMID: 29998350 DOI: 10.1007/s00221-018-5329-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 07/04/2018] [Indexed: 10/28/2022]
Abstract
The current study examines the modulation of the motion-onset response based on the frequency-range of sound stimuli. Delayed motion-onset and stationary stimuli were presented in a free-field by sequentially activating loudspeakers on an azimuthal plane keeping the natural percept of externalized sound presentation. The sounds were presented in low- or high-frequency ranges and had different motion direction within each hemifield. Difference waves were calculated by contrasting the moving and stationary sounds to isolate the motion-onset responses. Analyses carried out at the peak amplitudes and latencies on the difference waves showed that the early part of the motion response (cN1) was modulated by the frequency range of the sounds with stronger amplitudes elicited by stimuli with high frequency range. Subsequent post hoc analysis of the normalized amplitude of the motion response confirmed the previous finding by excluding the possibility that the frequency range had an overall effect on the waveform, and showing that this effect was instead limited to the motion response. These results support the idea of a modular organization of the motion-onset response with the processing of primary sound motion characteristics being reflected in the early part of the response. Also, the article highlights the importance of specificity in auditory stimulus design.
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Wasmuht DF, Pena JL, Gutfreund Y. Stimulus-specific adaptation to visual but not auditory motion direction in the barn owl's optic tectum. Eur J Neurosci 2016; 45:610-621. [PMID: 27987375 DOI: 10.1111/ejn.13505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 12/11/2016] [Accepted: 12/12/2016] [Indexed: 12/01/2022]
Abstract
Whether the auditory and visual systems use a similar coding strategy to represent motion direction is an open question. We investigated this question in the barn owl's optic tectum (OT) testing stimulus-specific adaptation (SSA) to the direction of motion. SSA, the reduction of the response to a repetitive stimulus that does not generalize to other stimuli, has been well established in OT neurons. SSA suggests a separate representation of the adapted stimulus in upstream pathways. So far, only SSA to static stimuli has been studied in the OT. Here, we examined adaptation to moving auditory and visual stimuli. SSA to motion direction was examined using repeated presentations of moving stimuli, occasionally switching motion to the opposite direction. Acoustic motion was either mimicked by varying binaural spatial cues or implemented in free field using a speaker array. While OT neurons displayed SSA to motion direction in visual space, neither stimulation paradigms elicited significant SSA to auditory motion direction. These findings show a qualitative difference in how auditory and visual motion is processed in the OT and support the existence of dedicated circuitry for representing motion direction in the early stages of visual but not the auditory system.
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Affiliation(s)
- Dante F Wasmuht
- Department of Neuroscience, The Ruth and Bruce Rappaport Faculty of Medicine and Research Institute, The Technion, Bat-Galim, Haifa, 31096, Israel
| | - Jose L Pena
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Yoram Gutfreund
- Department of Neuroscience, The Ruth and Bruce Rappaport Faculty of Medicine and Research Institute, The Technion, Bat-Galim, Haifa, 31096, Israel
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Andreeva IG. The motion aftereffect as a universal phenomenon in sensory systems involved in space orientation: II. Auditory motion aftereffect. J EVOL BIOCHEM PHYS+ 2015. [DOI: 10.1134/s0022093015030015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Shestopalova L, Petropavlovskaia E, Vaitulevich S, Nikitin N. Contextual effects on preattentive processing of sound motion as revealed by spatial MMN. Int J Psychophysiol 2015; 96:49-56. [DOI: 10.1016/j.ijpsycho.2015.02.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 02/13/2015] [Accepted: 02/17/2015] [Indexed: 10/24/2022]
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Abstract
The auditory system derives locations of sound sources from spatial cues provided by the interaction of sound with the head and external ears. Those cues are analyzed in specific brainstem pathways and then integrated as cortical representation of locations. The principal cues for horizontal localization are interaural time differences (ITDs) and interaural differences in sound level (ILDs). Vertical and front/back localization rely on spectral-shape cues derived from direction-dependent filtering properties of the external ears. The likely first sites of analysis of these cues are the medial superior olive (MSO) for ITDs, lateral superior olive (LSO) for ILDs, and dorsal cochlear nucleus (DCN) for spectral-shape cues. Localization in distance is much less accurate than that in horizontal and vertical dimensions, and interpretation of the basic cues is influenced by additional factors, including acoustics of the surroundings and familiarity of source spectra and levels. Listeners are quite sensitive to sound motion, but it remains unclear whether that reflects specific motion detection mechanisms or simply detection of changes in static location. Intact auditory cortex is essential for normal sound localization. Cortical representation of sound locations is highly distributed, with no evidence for point-to-point topography. Spatial representation is strictly contralateral in laboratory animals that have been studied, whereas humans show a prominent right-hemisphere dominance.
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Affiliation(s)
- John C Middlebrooks
- Departments of Otolaryngology, Neurobiology and Behavior, Cognitive Sciences, and Biomedical Engineering, University of California at Irvine, Irvine, CA, USA.
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Freeman TCA, Leung J, Wufong E, Orchard-Mills E, Carlile S, Alais D. Discrimination contours for moving sounds reveal duration and distance cues dominate auditory speed perception. PLoS One 2014; 9:e102864. [PMID: 25076211 PMCID: PMC4116163 DOI: 10.1371/journal.pone.0102864] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 06/25/2014] [Indexed: 11/18/2022] Open
Abstract
Evidence that the auditory system contains specialised motion detectors is mixed. Many psychophysical studies confound speed cues with distance and duration cues and present sound sources that do not appear to move in external space. Here we use the 'discrimination contours' technique to probe the probabilistic combination of speed, distance and duration for stimuli moving in a horizontal arc around the listener in virtual auditory space. The technique produces a set of motion discrimination thresholds that define a contour in the distance-duration plane for different combination of the three cues, based on a 3-interval oddity task. The orientation of the contour (typically elliptical in shape) reveals which cue or combination of cues dominates. If the auditory system contains specialised motion detectors, stimuli moving over different distances and durations but defining the same speed should be more difficult to discriminate. The resulting discrimination contours should therefore be oriented obliquely along iso-speed lines within the distance-duration plane. However, we found that over a wide range of speeds, distances and durations, the ellipses aligned with distance-duration axes and were stretched vertically, suggesting that listeners were most sensitive to duration. A second experiment showed that listeners were able to make speed judgements when distance and duration cues were degraded by noise, but that performance was worse. Our results therefore suggest that speed is not a primary cue to motion in the auditory system, but that listeners are able to use speed to make discrimination judgements when distance and duration cues are unreliable.
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Affiliation(s)
| | - Johahn Leung
- Auditory Neuroscience Laboratory, Department of Physiology and Bosch Institute, School of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Ella Wufong
- School of Psychology, University of Sydney, Sydney, New South Wales, Australia
| | - Emily Orchard-Mills
- School of Psychology, University of Sydney, Sydney, New South Wales, Australia
| | - Simon Carlile
- Auditory Neuroscience Laboratory, Department of Physiology and Bosch Institute, School of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - David Alais
- School of Psychology, University of Sydney, Sydney, New South Wales, Australia
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Grzeschik R, Böckmann-Barthel M, Mühler R, Verhey JL, Hoffmann MB. Direction-specific adaptation of motion-onset auditory evoked potentials. Eur J Neurosci 2013; 38:2557-65. [PMID: 23725339 DOI: 10.1111/ejn.12264] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 04/12/2013] [Accepted: 04/26/2013] [Indexed: 11/26/2022]
Abstract
Auditory evoked potentials (AEPs) to motion onset in humans are dominated by a fronto-central complex, with a change-negative deflection 1 (cN1) and a change-positive deflection 2 (cP2) component. Here the contribution of veridical motion detectors to motion-onset AEPs was investigated with the hypothesis that direction-specific adaptation effects would indicate the contribution of such motion detectors. AEPs were recorded from 33 electroencephalographic channels to the test stimulus, i.e. motion onset of horizontal virtual auditory motion (60° per s) from straight ahead to the left. AEPs were compared in two experiments for three conditions, which differed in their history prior to the motion-onset test stimulus: (i) without motion history (Baseline), (ii) with motion history in the same direction as the test stimulus (Adaptation Same), and (iii) a reference condition with auditory history. For Experiment 1, condition (iii) comprised motion in the opposite direction (Adaptation Opposite). For Experiment 2, a noise in the absence of coherent motion (Matched Noise) was used as the reference condition. In Experiment 1, the amplitude difference cP2 - cN1 obtained for Adaptation Same was significantly smaller than for Baseline and Adaptation Opposite. In Experiment 2, it was significantly smaller than for Matched Noise. Adaptation effects were absent for cN1 and cP2 latencies. These findings demonstrate direction-specific adaptation of the motion-onset AEP. This suggests that veridical auditory motion detectors contribute to the motion-onset AEP.
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Affiliation(s)
- Ramona Grzeschik
- Department of Ophthalmology, Visual Processing Laboratory, Otto von Guericke University Magdeburg, Leipziger Strasse 44, 39120, Magdeburg, Germany
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