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Tang B, Li K, Cheng Y, Zhang G, An P, Sun Y, Fang Y, Liu H, Shen Y, Zhang Y, Shan Y, de Villers-Sidani É, Zhou X. Developmental Exposure to Bisphenol a Degrades Auditory Cortical Processing in Rats. Neurosci Bull 2022; 38:1292-1302. [PMID: 35670954 PMCID: PMC9672238 DOI: 10.1007/s12264-022-00891-0] [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: 12/11/2021] [Accepted: 03/08/2022] [Indexed: 10/18/2022] Open
Abstract
Developmental exposure to bisphenol A (BPA), an endocrine-disrupting contaminant, impairs cognitive function in both animals and humans. However, whether BPA affects the development of primary sensory systems, which are the first to mature in the cortex, remains largely unclear. Using the rat as a model, we aimed to record the physiological and structural changes in the primary auditory cortex (A1) following lactational BPA exposure and their possible effects on behavioral outcomes. We found that BPA-exposed rats showed significant behavioral impairments when performing a sound temporal rate discrimination test. A significant alteration in spectral and temporal processing was also recorded in their A1, manifested as degraded frequency selectivity and diminished stimulus rate-following by neurons. These post-exposure effects were accompanied by changes in the density and maturity of dendritic spines in A1. Our findings demonstrated developmental impacts of BPA on auditory cortical processing and auditory-related discrimination, particularly in the temporal domain. Thus, the health implications for humans associated with early exposure to endocrine disruptors such as BPA merit more careful examination.
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Affiliation(s)
- Binliang Tang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Kailin Li
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Yuan Cheng
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Guimin Zhang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Pengying An
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Yutian Sun
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Yue Fang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Hui Liu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Yang Shen
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Yifan Zhang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China
| | - Ye Shan
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China
| | - Étienne de Villers-Sidani
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada
| | - Xiaoming Zhou
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai, 200062, China.
- New York University-East China Normal University Institute of Brain and Cognitive Science, NYU-Shanghai, Shanghai, 200062, China.
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Montes-Lourido P, Kar M, Pernia M, Parida S, Sadagopan S. Updates to the guinea pig animal model for in-vivo auditory neuroscience in the low-frequency hearing range. Hear Res 2022; 424:108603. [PMID: 36099806 PMCID: PMC9922531 DOI: 10.1016/j.heares.2022.108603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/29/2022] [Accepted: 09/03/2022] [Indexed: 02/08/2023]
Abstract
For gaining insight into general principles of auditory processing, it is critical to choose model organisms whose set of natural behaviors encompasses the processes being investigated. This reasoning has led to the development of a variety of animal models for auditory neuroscience research, such as guinea pigs, gerbils, chinchillas, rabbits, and ferrets; but in recent years, the availability of cutting-edge molecular tools and other methodologies in the mouse model have led to waning interest in these unique model species. As laboratories increasingly look to include in-vivo components in their research programs, a comprehensive description of procedures and techniques for applying some of these modern neuroscience tools to a non-mouse small animal model would enable researchers to leverage unique model species that may be best suited for testing their specific hypotheses. In this manuscript, we describe in detail the methods we have developed to apply these tools to the guinea pig animal model to answer questions regarding the neural processing of complex sounds, such as vocalizations. We describe techniques for vocalization acquisition, behavioral testing, recording of auditory brainstem responses and frequency-following responses, intracranial neural signals including local field potential and single unit activity, and the expression of transgenes allowing for optogenetic manipulation of neural activity, all in awake and head-fixed guinea pigs. We demonstrate the rich datasets at the behavioral and electrophysiological levels that can be obtained using these techniques, underscoring the guinea pig as a versatile animal model for studying complex auditory processing. More generally, the methods described here are applicable to a broad range of small mammals, enabling investigators to address specific auditory processing questions in model organisms that are best suited for answering them.
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Affiliation(s)
- Pilar Montes-Lourido
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Manaswini Kar
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA; Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Marianny Pernia
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Satyabrata Parida
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA
| | - Srivatsun Sadagopan
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA, USA; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA, USA; Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA; Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA; Department of Communication Science and Disorders, University of Pittsburgh, Pittsburgh, PA, USA.
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3
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Ruthig P, Schönwiesner M. Common principles in the lateralisation of auditory cortex structure and function for vocal communication in primates and rodents. Eur J Neurosci 2022; 55:827-845. [PMID: 34984748 DOI: 10.1111/ejn.15590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/24/2021] [Indexed: 11/27/2022]
Abstract
This review summarises recent findings on the lateralisation of communicative sound processing in the auditory cortex (AC) of humans, non-human primates, and rodents. Functional imaging in humans has demonstrated a left hemispheric preference for some acoustic features of speech, but it is unclear to which degree this is caused by bottom-up acoustic feature selectivity or top-down modulation from language areas. Although non-human primates show a less pronounced functional lateralisation in AC, the properties of AC fields and behavioral asymmetries are qualitatively similar. Rodent studies demonstrate microstructural circuits that might underlie bottom-up acoustic feature selectivity in both hemispheres. Functionally, the left AC in the mouse appears to be specifically tuned to communication calls, whereas the right AC may have a more 'generalist' role. Rodents also show anatomical AC lateralisation, such as differences in size and connectivity. Several of these functional and anatomical characteristics are also lateralized in human AC. Thus, complex vocal communication processing shares common features among rodents and primates. We argue that a synthesis of results from humans, non-human primates, and rodents is necessary to identify the neural circuitry of vocal communication processing. However, data from different species and methods are often difficult to compare. Recent advances may enable better integration of methods across species. Efforts to standardise data formats and analysis tools would benefit comparative research and enable synergies between psychological and biological research in the area of vocal communication processing.
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Affiliation(s)
- Philip Ruthig
- Faculty of Life Sciences, Leipzig University, Leipzig, Sachsen.,Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig
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4
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Montes-Lourido P, Kar M, David SV, Sadagopan S. Neuronal selectivity to complex vocalization features emerges in the superficial layers of primary auditory cortex. PLoS Biol 2021; 19:e3001299. [PMID: 34133413 PMCID: PMC8238193 DOI: 10.1371/journal.pbio.3001299] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 06/28/2021] [Accepted: 05/24/2021] [Indexed: 01/11/2023] Open
Abstract
Early in auditory processing, neural responses faithfully reflect acoustic input. At higher stages of auditory processing, however, neurons become selective for particular call types, eventually leading to specialized regions of cortex that preferentially process calls at the highest auditory processing stages. We previously proposed that an intermediate step in how nonselective responses are transformed into call-selective responses is the detection of informative call features. But how neural selectivity for informative call features emerges from nonselective inputs, whether feature selectivity gradually emerges over the processing hierarchy, and how stimulus information is represented in nonselective and feature-selective populations remain open question. In this study, using unanesthetized guinea pigs (GPs), a highly vocal and social rodent, as an animal model, we characterized the neural representation of calls in 3 auditory processing stages-the thalamus (ventral medial geniculate body (vMGB)), and thalamorecipient (L4) and superficial layers (L2/3) of primary auditory cortex (A1). We found that neurons in vMGB and A1 L4 did not exhibit call-selective responses and responded throughout the call durations. However, A1 L2/3 neurons showed high call selectivity with about a third of neurons responding to only 1 or 2 call types. These A1 L2/3 neurons only responded to restricted portions of calls suggesting that they were highly selective for call features. Receptive fields of these A1 L2/3 neurons showed complex spectrotemporal structures that could underlie their high call feature selectivity. Information theoretic analysis revealed that in A1 L4, stimulus information was distributed over the population and was spread out over the call durations. In contrast, in A1 L2/3, individual neurons showed brief bursts of high stimulus-specific information and conveyed high levels of information per spike. These data demonstrate that a transformation in the neural representation of calls occurs between A1 L4 and A1 L2/3, leading to the emergence of a feature-based representation of calls in A1 L2/3. Our data thus suggest that observed cortical specializations for call processing emerge in A1 and set the stage for further mechanistic studies.
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Affiliation(s)
- Pilar Montes-Lourido
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Manaswini Kar
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Stephen V. David
- Department of Otolaryngology, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Srivatsun Sadagopan
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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5
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Yao JD, Sanes DH. Temporal Encoding is Required for Categorization, But Not Discrimination. Cereb Cortex 2021; 31:2886-2897. [PMID: 33429423 DOI: 10.1093/cercor/bhaa396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/26/2020] [Accepted: 11/03/2020] [Indexed: 11/14/2022] Open
Abstract
Core auditory cortex (AC) neurons encode slow fluctuations of acoustic stimuli with temporally patterned activity. However, whether temporal encoding is necessary to explain auditory perceptual skills remains uncertain. Here, we recorded from gerbil AC neurons while they discriminated between a 4-Hz amplitude modulation (AM) broadband noise and AM rates >4 Hz. We found a proportion of neurons possessed neural thresholds based on spike pattern or spike count that were better than the recorded session's behavioral threshold, suggesting that spike count could provide sufficient information for this perceptual task. A population decoder that relied on temporal information outperformed a decoder that relied on spike count alone, but the spike count decoder still remained sufficient to explain average behavioral performance. This leaves open the possibility that more demanding perceptual judgments require temporal information. Thus, we asked whether accurate classification of different AM rates between 4 and 12 Hz required the information contained in AC temporal discharge patterns. Indeed, accurate classification of these AM stimuli depended on the inclusion of temporal information rather than spike count alone. Overall, our results compare two different representations of time-varying acoustic features that can be accessed by downstream circuits required for perceptual judgments.
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Affiliation(s)
- Justin D Yao
- Center for Neural Science, New York University, New York, NY 10003, USA
| | - Dan H Sanes
- Center for Neural Science, New York University, New York, NY 10003, USA.,Department of Psychology, New York University, New York, NY 10003, USA.,Department of Biology, New York University, New York, NY 10003, USA.,Neuroscience Institute, NYU Langone Medical Center, New York University, New York, NY 10016, USA
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6
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Johnson JCS, Marshall CR, Weil RS, Bamiou DE, Hardy CJD, Warren JD. Hearing and dementia: from ears to brain. Brain 2021; 144:391-401. [PMID: 33351095 PMCID: PMC7940169 DOI: 10.1093/brain/awaa429] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/02/2020] [Accepted: 10/17/2020] [Indexed: 12/19/2022] Open
Abstract
The association between hearing impairment and dementia has emerged as a major public health challenge, with significant opportunities for earlier diagnosis, treatment and prevention. However, the nature of this association has not been defined. We hear with our brains, particularly within the complex soundscapes of everyday life: neurodegenerative pathologies target the auditory brain, and are therefore predicted to damage hearing function early and profoundly. Here we present evidence for this proposition, based on structural and functional features of auditory brain organization that confer vulnerability to neurodegeneration, the extensive, reciprocal interplay between 'peripheral' and 'central' hearing dysfunction, and recently characterized auditory signatures of canonical neurodegenerative dementias (Alzheimer's disease, Lewy body disease and frontotemporal dementia). Moving beyond any simple dichotomy of ear and brain, we argue for a reappraisal of the role of auditory cognitive dysfunction and the critical coupling of brain to peripheral organs of hearing in the dementias. We call for a clinical assessment of real-world hearing in these diseases that moves beyond pure tone perception to the development of novel auditory 'cognitive stress tests' and proximity markers for the early diagnosis of dementia and management strategies that harness retained auditory plasticity.
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Affiliation(s)
- Jeremy C S Johnson
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Charles R Marshall
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
- Preventive Neurology Unit, Wolfson Institute of Preventive Medicine, Queen Mary University of London, London, UK
| | - Rimona S Weil
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
- Movement Disorders Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London, UK
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Doris-Eva Bamiou
- UCL Ear Institute and UCL/UCLH Biomedical Research Centre, National Institute for Health Research, University College London, London, UK
| | - Chris J D Hardy
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Jason D Warren
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
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7
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Huang P, Xiang X, Chen X, Li H. Somatostatin Neurons Govern Theta Oscillations Induced by Salient Visual Signals. Cell Rep 2020; 33:108415. [PMID: 33238116 DOI: 10.1016/j.celrep.2020.108415] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 09/14/2020] [Accepted: 10/29/2020] [Indexed: 01/21/2023] Open
Abstract
Salient visual stimuli enhance theta oscillations and spike-phase locking in the theta band in the primary visual cortex (V1) of mice; however, the detailed mechanisms remain unknown. GABAergic neurons play a vital role in regulating these oscillations. Here, we use optogenetic recordings to tag cell-type-specific neurons in V1 of head-fixed mice and demonstrate that salient visual stimuli facilitate somatostatin (SOM)-expressing neuron responses and firing with theta band oscillations but suppress activities of parvalbumin (PV)-expressing neurons. Furthermore, inactivation of SOM neurons attenuates the enhancement of theta oscillations induced by salient visual stimuli and rhythmic activation of SOM neurons enhances theta oscillations. These results reveal a potential cortical theta oscillation mechanism governed by SOM neurons.
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Affiliation(s)
- Pengcheng Huang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, Collaborative Innovation Center for Biomedical Engineering, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xinkuan Xiang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, Collaborative Innovation Center for Biomedical Engineering, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xinfeng Chen
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, Collaborative Innovation Center for Biomedical Engineering, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Haohong Li
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; MoE Key Laboratory for Biomedical Photonics, Collaborative Innovation Center for Biomedical Engineering, School of Engineering Sciences, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
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8
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Gaucher Q, Yger P, Edeline JM. Increasing excitation versus decreasing inhibition in auditory cortex: consequences on the discrimination performance between communication sounds. J Physiol 2020; 598:3765-3785. [PMID: 32538485 DOI: 10.1113/jp279902] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/08/2020] [Indexed: 12/18/2022] Open
Abstract
KEY POINTS Enhancing cortical excitability can be achieved by either reducing intracortical inhibition or by enhancing intracortical excitation. Here we compare the consequences of reducing intracortical inhibition and of enhancing intracortical excitation on the processing of communication sounds in the primary auditory cortex. Local application of gabazine and of AMPA enlarged the spectrotemporal receptive fields and increased the responses to communication to the same extent. The Mutual Information (an index of the cortical neurons' ability to discriminate between natural sounds) was increased in both cases, as were the noise and signal correlations. Spike-timing reliability was only increased after gabazine application and post-excitation suppression was affected in the opposite way: it was increased when reducing the intracortical inhibition but was eliminated by enhancing the excitation. A computational model suggests that these results can be explained by an additive effect vs. a multiplicative effect ABSTRACT: The level of excitability of cortical circuits is often viewed as one of the critical factors controlling perceptive performance. In theory, enhancing cortical excitability can be achieved either by reducing inhibitory currents or by increasing excitatory currents. Here, we evaluated whether reducing inhibitory currents or increasing excitatory currents in auditory cortex similarly affects the neurons' ability to discriminate between communication sounds. We attenuated the inhibitory currents by application of gabazine (GBZ), and increased the excitatory currents by applying AMPA in the auditory cortex while testing frequency receptive fields and responses to communication sounds. GBZ and AMPA enlarged the receptive fields and increased the responses to communication sounds to the same extent. The spike-timing reliability of neuronal responses was largely increased when attenuating the intracortical inhibition but not after increasing the excitation. The discriminative abilities of cortical cells increased in both cases but this increase was more pronounced after attenuating the inhibition. The shape of the response to communication sounds was modified in the opposite direction: reducing inhibition increased post-excitation suppression whereas this suppression tended to disappear when increasing the excitation. A computational model indicates that the additive effect promoted by AMPA vs. the multiplicative effect of GBZ on neuronal responses, together with the dynamics of spontaneous cortical activity, can explain these differences. Thus, although apparently equivalent for increasing cortical excitability, acting on inhibition vs. on excitation impacts differently the cortical ability to discriminate natural stimuli, and only modulating inhibition changed efficiently the cortical representation of communication sounds.
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Affiliation(s)
- Quentin Gaucher
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), Department Cognition and Behaviour, CNRS UMR 9197, Orsay Cedex, 91405, France.,Université Paris-Sud, Bâtiment 446, Orsay Cedex, 91405, France
| | - Pierre Yger
- Institut de la Vision, INSERM UMRS 968, UPMC UM 80, CNRS UMR 7210, Paris, France
| | - Jean-Marc Edeline
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), Department Cognition and Behaviour, CNRS UMR 9197, Orsay Cedex, 91405, France.,Université Paris-Sud, Bâtiment 446, Orsay Cedex, 91405, France
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9
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García-Rosales F, López-Jury L, González-Palomares E, Cabral-Calderín Y, Hechavarría JC. Fronto-Temporal Coupling Dynamics During Spontaneous Activity and Auditory Processing in the Bat Carollia perspicillata. Front Syst Neurosci 2020; 14:14. [PMID: 32265670 PMCID: PMC7098971 DOI: 10.3389/fnsys.2020.00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/28/2020] [Indexed: 11/17/2022] Open
Abstract
Most mammals rely on the extraction of acoustic information from the environment in order to survive. However, the mechanisms that support sound representation in auditory neural networks involving sensory and association brain areas remain underexplored. In this study, we address the functional connectivity between an auditory region in frontal cortex (the frontal auditory field, FAF) and the auditory cortex (AC) in the bat Carollia perspicillata. The AC is a classic sensory area central for the processing of acoustic information. On the other hand, the FAF belongs to the frontal lobe, a brain region involved in the integration of sensory inputs, modulation of cognitive states, and in the coordination of behavioral outputs. The FAF-AC network was examined in terms of oscillatory coherence (local-field potentials, LFPs), and within an information theoretical framework linking FAF and AC spiking activity. We show that in the absence of acoustic stimulation, simultaneously recorded LFPs from FAF and AC are coherent in low frequencies (1-12 Hz). This "default" coupling was strongest in deep AC layers and was unaltered by acoustic stimulation. However, presenting auditory stimuli did trigger the emergence of coherent auditory-evoked gamma-band activity (>25 Hz) between the FAF and AC. In terms of spiking, our results suggest that FAF and AC engage in distinct coding strategies for representing artificial and natural sounds. Taken together, our findings shed light onto the neuronal coding strategies and functional coupling mechanisms that enable sound representation at the network level in the mammalian brain.
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Affiliation(s)
| | - Luciana López-Jury
- Institut für Zellbiologie und Neurowissenschaft, Goethe-Universität, Frankfurt, Germany
| | | | - Yuranny Cabral-Calderín
- Research Group Neural and Environmental Rhythms, MPI for Empirical Aesthetics, Frankfurt, Germany
| | - Julio C. Hechavarría
- Institut für Zellbiologie und Neurowissenschaft, Goethe-Universität, Frankfurt, Germany
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10
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Hörpel SG, Firzlaff U. Post-natal development of the envelope following response to amplitude modulated sounds in the bat Phyllostomus discolor. Hear Res 2020; 388:107904. [PMID: 32028065 DOI: 10.1016/j.heares.2020.107904] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/20/2019] [Accepted: 01/24/2020] [Indexed: 01/15/2023]
Abstract
Bats use a large repertoire of calls for social communication, which are often characterized by temporal amplitude and frequency modulations. As bats are considered to be among the few mammalian species capable of vocal learning, the perception of temporal sound modulations should be crucial for juvenile bats to develop social communication abilities. However, the post-natal development of auditory processing of temporal modulations has not been investigated in bats, so far. Here we use the minimally invasive technique of recording auditory brainstem responses to measure the envelope following response (EFR) to sinusoidally amplitude modulated noise (range of modulation frequencies: 11-130 Hz) in three juveniles (p8-p72) of the bat, Phyllostomus discolor. In two out of three animals, we show that although amplitude modulation processing is basically developed at p8, EFRs maturated further over a period of about two weeks until p33. Maturation of the EFR generally took longer for higher modulation frequencies (87-130 Hz) than for lower modulation frequencies (11-58 Hz).
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Affiliation(s)
- Stephen Gareth Hörpel
- Department of Animal Sciences, Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising, Germany.
| | - Uwe Firzlaff
- Department of Animal Sciences, Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising, Germany
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11
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Schicknick H, Henschke JU, Budinger E, Ohl FW, Gundelfinger ED, Tischmeyer W. β-adrenergic modulation of discrimination learning and memory in the auditory cortex. Eur J Neurosci 2019; 50:3141-3163. [PMID: 31162753 PMCID: PMC6900137 DOI: 10.1111/ejn.14480] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 05/27/2019] [Accepted: 05/31/2019] [Indexed: 01/11/2023]
Abstract
Despite vast literature on catecholaminergic neuromodulation of auditory cortex functioning in general, knowledge about its role for long‐term memory formation is scarce. Our previous pharmacological studies on cortex‐dependent frequency‐modulated tone‐sweep discrimination learning of Mongolian gerbils showed that auditory‐cortical D1/5‐dopamine receptor activity facilitates memory consolidation and anterograde memory formation. Considering overlapping functions of D1/5‐dopamine receptors and β‐adrenoceptors, we hypothesised a role of β‐adrenergic signalling in the auditory cortex for sweep discrimination learning and memory. Supporting this hypothesis, the β1/2‐adrenoceptor antagonist propranolol bilaterally applied to the gerbil auditory cortex after task acquisition prevented the discrimination increment that was normally monitored 1 day later. The increment in the total number of hurdle crossings performed in response to the sweeps per se was normal. Propranolol infusion after the seventh training session suppressed the previously established sweep discrimination. The suppressive effect required antagonist injection in a narrow post‐session time window. When applied to the auditory cortex 1 day before initial conditioning, β1‐adrenoceptor‐antagonising and β1‐adrenoceptor‐stimulating agents retarded and facilitated, respectively, sweep discrimination learning, whereas β2‐selective drugs were ineffective. In contrast, single‐sweep detection learning was normal after propranolol infusion. By immunohistochemistry, β1‐ and β2‐adrenoceptors were identified on the neuropil and somata of pyramidal and non‐pyramidal neurons of the gerbil auditory cortex. The present findings suggest that β‐adrenergic signalling in the auditory cortex has task‐related importance for discrimination learning of complex sounds: as previously shown for D1/5‐dopamine receptor signalling, β‐adrenoceptor activity supports long‐term memory consolidation and reconsolidation; additionally, tonic input through β1‐adrenoceptors may control mechanisms permissive for memory acquisition.
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Affiliation(s)
- Horst Schicknick
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Julia U Henschke
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Institute of Cognitive Neurology and Dementia Research, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Eike Budinger
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Frank W Ohl
- Department Systems Physiology of Learning, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany.,Institute of Biology, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Eckart D Gundelfinger
- Center for Behavioral Brain Sciences, Magdeburg, Germany.,Department Neurochemistry and Molecular Biology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Molecular Neurobiology, Medical Faculty, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Wolfgang Tischmeyer
- Special Lab Molecular Biological Techniques, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
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12
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Hörpel SG, Firzlaff U. Processing of fast amplitude modulations in bat auditory cortex matches communication call-specific sound features. J Neurophysiol 2019; 121:1501-1512. [PMID: 30785811 DOI: 10.1152/jn.00748.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bats use a large repertoire of calls for social communication. In the bat Phyllostomus discolor, social communication calls are often characterized by sinusoidal amplitude and frequency modulations with modulation frequencies in the range of 100-130 Hz. However, peaks in mammalian auditory cortical modulation transfer functions are typically limited to modulation frequencies below 100 Hz. We investigated the coding of sinusoidally amplitude modulated sounds in auditory cortical neurons in P. discolor by constructing rate and temporal modulation transfer functions. Neuronal responses to playbacks of various communication calls were additionally recorded and compared with the neurons' responses to sinusoidally amplitude-modulated sounds. Cortical neurons in the posterior dorsal field of the auditory cortex were tuned to unusually high modulation frequencies: rate modulation transfer functions often peaked around 130 Hz (median: 87 Hz), and the median of the highest modulation frequency that evoked significant phase-locking was also 130 Hz. Both values are much higher than reported from the auditory cortex of other mammals, with more than 51% of the units preferring modulation frequencies exceeding 100 Hz. Conspicuously, the fast modulations preferred by the neurons match the fast amplitude and frequency modulations of prosocial, and mostly of aggressive, communication calls in P. discolor. We suggest that the preference for fast amplitude modulations in the P. discolor dorsal auditory cortex serves to reliably encode the fast modulations seen in their communication calls. NEW & NOTEWORTHY Neural processing of temporal sound features is crucial for the analysis of communication calls. In bats, these calls are often characterized by fast temporal envelope modulations. Because auditory cortex neurons typically encode only low modulation frequencies, it is unclear how species-specific vocalizations are cortically processed. We show that auditory cortex neurons in the bat Phyllostomus discolor encode fast temporal envelope modulations. This property improves response specificity to communication calls and thus might support species-specific communication.
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Affiliation(s)
- Stephen Gareth Hörpel
- Chair of Zoology, Department of Animal Sciences, Technical University of Munich , Freising , Germany
| | - Uwe Firzlaff
- Chair of Zoology, Department of Animal Sciences, Technical University of Munich , Freising , Germany
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13
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Occelli F, Lameth J, Adenis V, Huetz C, Lévêque P, Jay TM, Edeline JM, Mallat M. A Single Exposure to GSM-1800 MHz Signals in the Course of an Acute Neuroinflammatory Reaction can Alter Neuronal Responses and Microglial Morphology in the Rat Primary Auditory Cortex. Neuroscience 2018; 385:11-24. [DOI: 10.1016/j.neuroscience.2018.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 05/10/2018] [Accepted: 06/01/2018] [Indexed: 12/21/2022]
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14
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Felix RA, Gourévitch B, Portfors CV. Subcortical pathways: Towards a better understanding of auditory disorders. Hear Res 2018; 362:48-60. [PMID: 29395615 PMCID: PMC5911198 DOI: 10.1016/j.heares.2018.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/11/2017] [Accepted: 01/16/2018] [Indexed: 01/13/2023]
Abstract
Hearing loss is a significant problem that affects at least 15% of the population. This percentage, however, is likely significantly higher because of a variety of auditory disorders that are not identifiable through traditional tests of peripheral hearing ability. In these disorders, individuals have difficulty understanding speech, particularly in noisy environments, even though the sounds are loud enough to hear. The underlying mechanisms leading to such deficits are not well understood. To enable the development of suitable treatments to alleviate or prevent such disorders, the affected processing pathways must be identified. Historically, mechanisms underlying speech processing have been thought to be a property of the auditory cortex and thus the study of auditory disorders has largely focused on cortical impairments and/or cognitive processes. As we review here, however, there is strong evidence to suggest that, in fact, deficits in subcortical pathways play a significant role in auditory disorders. In this review, we highlight the role of the auditory brainstem and midbrain in processing complex sounds and discuss how deficits in these regions may contribute to auditory dysfunction. We discuss current research with animal models of human hearing and then consider human studies that implicate impairments in subcortical processing that may contribute to auditory disorders.
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Affiliation(s)
- Richard A Felix
- School of Biological Sciences and Integrative Physiology and Neuroscience, Washington State University, Vancouver, WA, USA
| | - Boris Gourévitch
- Unité de Génétique et Physiologie de l'Audition, UMRS 1120 INSERM, Institut Pasteur, Université Pierre et Marie Curie, F-75015, Paris, France; CNRS, France
| | - Christine V Portfors
- School of Biological Sciences and Integrative Physiology and Neuroscience, Washington State University, Vancouver, WA, USA.
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15
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Aushana Y, Souffi S, Edeline JM, Lorenzi C, Huetz C. Robust Neuronal Discrimination in Primary Auditory Cortex Despite Degradations of Spectro-temporal Acoustic Details: Comparison Between Guinea Pigs with Normal Hearing and Mild Age-Related Hearing Loss. J Assoc Res Otolaryngol 2018; 19:163-180. [PMID: 29302822 PMCID: PMC5878150 DOI: 10.1007/s10162-017-0649-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 12/11/2017] [Indexed: 01/04/2023] Open
Abstract
This study investigated to which extent the primary auditory cortex of young normal-hearing and mild hearing-impaired aged animals is able to maintain invariant representation of critical temporal-modulation features when sounds are submitted to degradations of fine spectro-temporal acoustic details. This was achieved by recording ensemble of cortical responses to conspecific vocalizations in guinea pigs with either normal hearing or mild age-related sensorineural hearing loss. The vocalizations were degraded using a tone vocoder. The neuronal responses and their discrimination capacities (estimated by mutual information) were analyzed at single recording and population levels. For normal-hearing animals, the neuronal responses decreased as a function of the number of the vocoder frequency bands, so did their discriminative capacities at the single recording level. However, small neuronal populations were found to be robust to the degradations induced by the vocoder. Similar robustness was obtained when broadband noise was added to exacerbate further the spectro-temporal distortions produced by the vocoder. A comparable pattern of robustness to degradations in fine spectro-temporal details was found for hearing-impaired animals. However, the latter showed an overall decrease in neuronal discrimination capacities between vocalizations in noisy conditions. Consistent with previous studies, these results demonstrate that the primary auditory cortex maintains robust neural representation of temporal envelope features for communication sounds under a large range of spectro-temporal degradations.
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Affiliation(s)
- Yonane Aushana
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), CNRS UMR 9197, Orsay, France
- Université Paris-Sud, 91405 Orsay cedex, France
- Université Paris-Saclay, 91405 Orsay cedex, France
| | - Samira Souffi
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), CNRS UMR 9197, Orsay, France
- Université Paris-Sud, 91405 Orsay cedex, France
- Université Paris-Saclay, 91405 Orsay cedex, France
| | - Jean-Marc Edeline
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), CNRS UMR 9197, Orsay, France
- Université Paris-Sud, 91405 Orsay cedex, France
- Université Paris-Saclay, 91405 Orsay cedex, France
| | - Christian Lorenzi
- Laboratoire des Systèmes Perceptifs, UMR CNRS 8248, Département d’Etudes Cognitives, Ecole Normale Supérieure (ENS), Paris Sciences & Lettres Research University, 75005 Paris, France
| | - Chloé Huetz
- Paris-Saclay Institute of Neurosciences (Neuro-PSI), CNRS UMR 9197, Orsay, France
- Université Paris-Sud, 91405 Orsay cedex, France
- Université Paris-Saclay, 91405 Orsay cedex, France
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16
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17
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Audition and Hemispheric Specialization in Songbirds and New Evidence from Australian Magpies. Symmetry (Basel) 2017. [DOI: 10.3390/sym9070099] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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18
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Single Neurons in the Avian Auditory Cortex Encode Individual Identity and Propagation Distance in Naturally Degraded Communication Calls. J Neurosci 2017; 37:3491-3510. [PMID: 28235893 PMCID: PMC5373131 DOI: 10.1523/jneurosci.2220-16.2017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 01/08/2017] [Accepted: 01/13/2017] [Indexed: 11/21/2022] Open
Abstract
One of the most complex tasks performed by sensory systems is "scene analysis": the interpretation of complex signals as behaviorally relevant objects. The study of this problem, universal to species and sensory modalities, is particularly challenging in audition, where sounds from various sources and localizations, degraded by propagation through the environment, sum to form a single acoustical signal. Here we investigated in a songbird model, the zebra finch, the neural substrate for ranging and identifying a single source. We relied on ecologically and behaviorally relevant stimuli, contact calls, to investigate the neural discrimination of individual vocal signature as well as sound source distance when calls have been degraded through propagation in a natural environment. Performing electrophysiological recordings in anesthetized birds, we found neurons in the auditory forebrain that discriminate individual vocal signatures despite long-range degradation, as well as neurons discriminating propagation distance, with varying degrees of multiplexing between both information types. Moreover, the neural discrimination performance of individual identity was not affected by propagation-induced degradation beyond what was induced by the decreased intensity. For the first time, neurons with distance-invariant identity discrimination properties as well as distance-discriminant neurons are revealed in the avian auditory cortex. Because these neurons were recorded in animals that had prior experience neither with the vocalizers of the stimuli nor with long-range propagation of calls, we suggest that this neural population is part of a general-purpose system for vocalizer discrimination and ranging.SIGNIFICANCE STATEMENT Understanding how the brain makes sense of the multitude of stimuli that it continually receives in natural conditions is a challenge for scientists. Here we provide a new understanding of how the auditory system extracts behaviorally relevant information, the vocalizer identity and its distance to the listener, from acoustic signals that have been degraded by long-range propagation in natural conditions. We show, for the first time, that single neurons, in the auditory cortex of zebra finches, are capable of discriminating the individual identity and sound source distance in conspecific communication calls. The discrimination of identity in propagated calls relies on a neural coding that is robust to intensity changes, signals' quality, and decreases in the signal-to-noise ratio.
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Neural Representation of Concurrent Vowels in Macaque Primary Auditory Cortex. eNeuro 2016; 3:eN-NWR-0071-16. [PMID: 27294198 PMCID: PMC4901243 DOI: 10.1523/eneuro.0071-16.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 04/15/2016] [Indexed: 11/30/2022] Open
Abstract
Successful speech perception in real-world environments requires that the auditory system segregate competing voices that overlap in frequency and time into separate streams. Vowels are major constituents of speech and are comprised of frequencies (harmonics) that are integer multiples of a common fundamental frequency (F0). The pitch and identity of a vowel are determined by its F0 and spectral envelope (formant structure), respectively. When two spectrally overlapping vowels differing in F0 are presented concurrently, they can be readily perceived as two separate “auditory objects” with pitches at their respective F0s. A difference in pitch between two simultaneous vowels provides a powerful cue for their segregation, which in turn, facilitates their individual identification. The neural mechanisms underlying the segregation of concurrent vowels based on pitch differences are poorly understood. Here, we examine neural population responses in macaque primary auditory cortex (A1) to single and double concurrent vowels (/a/ and /i/) that differ in F0 such that they are heard as two separate auditory objects with distinct pitches. We find that neural population responses in A1 can resolve, via a rate-place code, lower harmonics of both single and double concurrent vowels. Furthermore, we show that the formant structures, and hence the identities, of single vowels can be reliably recovered from the neural representation of double concurrent vowels. We conclude that A1 contains sufficient spectral information to enable concurrent vowel segregation and identification by downstream cortical areas.
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20
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Hall AJ, Butler BE, Lomber SG. The cat's meow: A high-field fMRI assessment of cortical activity in response to vocalizations and complex auditory stimuli. Neuroimage 2016; 127:44-57. [DOI: 10.1016/j.neuroimage.2015.11.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 11/22/2015] [Accepted: 11/24/2015] [Indexed: 01/26/2023] Open
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21
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Mitchell RLC, Xu Y. What is the Value of Embedding Artificial Emotional Prosody in Human-Computer Interactions? Implications for Theory and Design in Psychological Science. Front Psychol 2015; 6:1750. [PMID: 26617563 PMCID: PMC4641894 DOI: 10.3389/fpsyg.2015.01750] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 10/31/2015] [Indexed: 11/18/2022] Open
Abstract
In computerized technology, artificial speech is becoming increasingly important, and is already used in ATMs, online gaming and healthcare contexts. However, today’s artificial speech typically sounds monotonous, a main reason for this being the lack of meaningful prosody. One particularly important function of prosody is to convey different emotions. This is because successful encoding and decoding of emotions is vital for effective social cognition, which is increasingly recognized in human–computer interaction contexts. Current attempts to artificially synthesize emotional prosody are much improved relative to early attempts, but there remains much work to be done due to methodological problems, lack of agreed acoustic correlates, and lack of theoretical grounding. If the addition of synthetic emotional prosody is not of sufficient quality, it may risk alienating users instead of enhancing their experience. So the value of embedding emotion cues in artificial speech may ultimately depend on the quality of the synthetic emotional prosody. However, early evidence on reactions to synthesized non-verbal cues in the facial modality bodes well. Attempts to implement the recognition of emotional prosody into artificial applications and interfaces have perhaps been met with greater success, but the ultimate test of synthetic emotional prosody will be to critically compare how people react to synthetic emotional prosody vs. natural emotional prosody, at the behavioral, socio-cognitive and neural levels.
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Affiliation(s)
- Rachel L C Mitchell
- Centre for Affective Disorders, Institute of Psychiatry Psychology and Neuroscience , King's College London, London, UK
| | - Yi Xu
- Speech Hearing and Phonetic Sciences, Division of Psychology and Language Sciences, University College London , London, UK
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22
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Abstract
Vertebrate audition is a dynamic process, capable of exhibiting both short- and long-term adaptations to varying listening conditions. Precise spike timing has long been known to play an important role in auditory encoding, but its role in sensory plasticity remains largely unexplored. We addressed this issue in Gambel's white-crowned sparrow (Zonotrichia leucophrys gambelii), a songbird that shows pronounced seasonal fluctuations in circulating levels of sex-steroid hormones, which are known to be potent neuromodulators of auditory function. We recorded extracellular single-unit activity in the auditory forebrain of males and females under different breeding conditions and used a computational approach to explore two potential strategies for the neural discrimination of sound level: one based on spike counts and one based on spike timing reliability. We report that breeding condition has robust sex-specific effects on spike timing. Specifically, in females, breeding condition increases the proportion of cells that rely solely on spike timing information and increases the temporal resolution required for optimal intensity encoding. Furthermore, in a functionally distinct subset of cells that are particularly well suited for amplitude encoding, female breeding condition enhances spike timing-based discrimination accuracy. No effects of breeding condition were observed in males. Our results suggest that high-resolution temporal discharge patterns may provide a plastic neural substrate for sensory coding.
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23
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Gaucher Q, Edeline JM. Stimulus-specific effects of noradrenaline in auditory cortex: implications for the discrimination of communication sounds. J Physiol 2014; 593:1003-20. [PMID: 25398527 DOI: 10.1113/jphysiol.2014.282855] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 11/02/2014] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Many studies have described the action of Noradrenaline (NA) on the properties of cortical receptive fields, but none has assessed how NA affects the discrimination abilities of cortical cells between natural stimuli. In the present study, we compared the consequences of NA topical application on spectro-temporal receptive fields (STRFs) and responses to communication sounds in the primary auditory cortex. NA application reduced the STRFs (an effect replicated by the alpha1 agonist Phenylephrine) but did not change, on average, the responses to communication sounds. For cells exhibiting increased evoked responses during NA application, the discrimination abilities were enhanced as quantified by Mutual Information. The changes induced by NA on parameters extracted from the STRFs and from responses to communication sounds were not related. ABSTRACT The alterations exerted by neuromodulators on neuronal selectivity have been the topic of a vast literature in the visual, somatosensory, auditory and olfactory cortices. However, very few studies have investigated to what extent the effects observed when testing these functional properties with artificial stimuli can be transferred to responses evoked by natural stimuli. Here, we tested the effect of noradrenaline (NA) application on the responses to pure tones and communication sounds in the guinea-pig primary auditory cortex. When pure tones were used to assess the spectro-temporal receptive field (STRF) of cortical cells, NA triggered a transient reduction of the STRFs in both the spectral and the temporal domain, an effect replicated by the α1 agonist phenylephrine whereas α2 and β agonists induced STRF expansion. When tested with communication sounds, NA application did not produce significant effects on the firing rate and spike timing reliability, despite the fact that α1, α2 and β agonists by themselves had significant effects on these measures. However, the cells whose evoked responses were increased by NA application displayed enhanced discriminative abilities. These cells had initially smaller STRFs than the rest of the population. A principal component analysis revealed that the variations of parameters extracted from the STRF and those extracted from the responses to natural stimuli were not correlated. These results suggest that probing the action of neuromodulators on cortical cells with artificial stimuli does not allow us to predict their action on responses to natural stimuli.
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Affiliation(s)
- Quentin Gaucher
- Centre de Neurosciences Paris-Sud (CNPS), CNRS UMR 8195, , Université Paris-Sud, Bâtiment 446, 91405, Orsay cedex, France
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24
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Christison-Lagay KL, Bennur S, Blackwell J, Lee JH, Schroeder T, Cohen YE. Natural variability in species-specific vocalizations constrains behavior and neural activity. Hear Res 2014; 312:128-42. [PMID: 24721001 PMCID: PMC4057037 DOI: 10.1016/j.heares.2014.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/07/2014] [Accepted: 03/13/2014] [Indexed: 11/30/2022]
Abstract
A listener's capacity to discriminate between sounds is related to the amount of acoustic variability that exists between these sounds. However, a full understanding of how this natural variability impacts neural activity and behavior is lacking. Here, we tested monkeys' ability to discriminate between different utterances of vocalizations from the same acoustic class (i.e., coos and grunts), while neural activity was simultaneously recorded in the anterolateral belt region (AL) of the auditory cortex, a brain region that is a part of a pathway that mediates auditory perception. Monkeys could discriminate between coos better than they could discriminate between grunts. We also found AL activity was more informative about different coos than different grunts. This difference could be attributed, in part, to our finding that coos had more acoustic variability than grunts. Thus, intrinsic acoustic variability constrained the discriminability of AL spike trains and the ability of rhesus monkeys to discriminate between vocalizations.
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Affiliation(s)
| | - Sharath Bennur
- Dept. Otorhinolaryngology, U. Pennsylvania, Philadelphia, PA 19104, USA
| | - Jennifer Blackwell
- Neuroscience Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jung H Lee
- Dept. Otorhinolaryngology, U. Pennsylvania, Philadelphia, PA 19104, USA
| | - Tim Schroeder
- Dept. Otorhinolaryngology, U. Pennsylvania, Philadelphia, PA 19104, USA
| | - Yale E Cohen
- Dept. Otorhinolaryngology, U. Pennsylvania, Philadelphia, PA 19104, USA; Neuroscience, U. Pennsylvania, Philadelphia, PA 19104, USA; Bioengineering, U. Pennsylvania, Philadelphia, PA 19104, USA.
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Huetz C, Guedin M, Edeline JM. Neural correlates of moderate hearing loss: time course of response changes in the primary auditory cortex of awake guinea-pigs. Front Syst Neurosci 2014; 8:65. [PMID: 24808831 PMCID: PMC4009414 DOI: 10.3389/fnsys.2014.00065] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 04/07/2014] [Indexed: 11/21/2022] Open
Abstract
Over the last decade, the consequences of acoustic trauma on the functional properties of auditory cortex neurons have received growing attention. Changes in spontaneous and evoked activity, shifts of characteristic frequency (CF), and map reorganizations have extensively been described in anesthetized animals (e.g., Noreña and Eggermont, 2003, 2005). Here, we examined how the functional properties of cortical cells are modified after partial hearing loss in awake guinea pigs. Single unit activity was chronically recorded in awake, restrained, guinea pigs from 3 days before up to 15 days after an acoustic trauma induced by a 5 kHz 110 dB tone delivered for 1 h. Auditory brainstem responses (ABRs) audiograms indicated that these parameters produced a mean ABR threshold shift of 20 dB SPL at, and one octave above, the trauma frequency. When tested with pure tones, cortical cells showed on average a 25 dB increase in threshold at CF the day following the trauma. Over days, this increase progressively stabilized at only 10 dB above control value indicating a progressive recovery of cortical thresholds, probably reflecting a progressive shift from temporary threshold shift (TTS) to permanent threshold shift (PTS). There was an increase in response latency and in response variability the day following the trauma but these parameters returned to control values within 3 days. When tested with conspecific vocalizations, cortical neurons also displayed an increase in response latency and in response duration the day after the acoustic trauma, but there was no effect on the average firing rate elicited by the vocalization. These findings suggest that, in cases of moderate hearing loss, the temporal precision of neuronal responses to natural stimuli is impaired despite the fact the firing rate showed little or no changes.
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Affiliation(s)
- Chloé Huetz
- Centre de Neurosciences Paris-Sud, CNRS, UMR 8195, Université Paris-Sud Orsay, France
| | - Maud Guedin
- Centre de Neurosciences Paris-Sud, CNRS, UMR 8195, Université Paris-Sud Orsay, France
| | - Jean-Marc Edeline
- Centre de Neurosciences Paris-Sud, CNRS, UMR 8195, Université Paris-Sud Orsay, France
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26
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Cortical inhibition reduces information redundancy at presentation of communication sounds in the primary auditory cortex. J Neurosci 2013; 33:10713-28. [PMID: 23804094 DOI: 10.1523/jneurosci.0079-13.2013] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In all sensory modalities, intracortical inhibition shapes the functional properties of cortical neurons but also influences the responses to natural stimuli. Studies performed in various species have revealed that auditory cortex neurons respond to conspecific vocalizations by temporal spike patterns displaying a high trial-to-trial reliability, which might result from precise timing between excitation and inhibition. Studying the guinea pig auditory cortex, we show that partial blockage of GABAA receptors by gabazine (GBZ) application (10 μm, a concentration that promotes expansion of cortical receptive fields) increased the evoked firing rate and the spike-timing reliability during presentation of communication sounds (conspecific and heterospecific vocalizations), whereas GABAB receptor antagonists [10 μm saclofen; 10-50 μm CGP55845 (p-3-aminopropyl-p-diethoxymethyl phosphoric acid)] had nonsignificant effects. Computing mutual information (MI) from the responses to vocalizations using either the evoked firing rate or the temporal spike patterns revealed that GBZ application increased the MI derived from the activity of single cortical site but did not change the MI derived from population activity. In addition, quantification of information redundancy showed that GBZ significantly increased redundancy at the population level. This result suggests that a potential role of intracortical inhibition is to reduce information redundancy during the processing of natural stimuli.
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