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Wallace MN, Berger JI, Hockley A, Sumner CJ, Akeroyd MA, Palmer AR, McNaughton PA. Identifying tinnitus in mice by tracking the motion of body markers in response to an acoustic startle. Front Neurosci 2024; 18:1452450. [PMID: 39170684 PMCID: PMC11335616 DOI: 10.3389/fnins.2024.1452450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 07/24/2024] [Indexed: 08/23/2024] Open
Abstract
Rodent models of tinnitus are commonly used to study its mechanisms and potential treatments. Tinnitus can be identified by changes in the gap-induced prepulse inhibition of the acoustic startle (GPIAS), most commonly by using pressure detectors to measure the whole-body startle (WBS). Unfortunately, the WBS habituates quickly, the measuring system can introduce mechanical oscillations and the response shows considerable variability. We have instead used a motion tracking system to measure the localized motion of small reflective markers in response to an acoustic startle reflex in guinea pigs and mice. For guinea pigs, the pinna had the largest responses both in terms of displacement between pairs of markers and in terms of the speed of the reflex movement. Smaller, but still reliable responses were observed with markers on the thorax, abdomen and back. The peak speed of the pinna reflex was the most sensitive measure for calculating GPIAS in the guinea pig. Recording the pinna reflex in mice proved impractical due to removal of the markers during grooming. However, recordings from their back and tail allowed us to measure the peak speed and the twitch amplitude (area under curve) of reflex responses and both analysis methods showed robust GPIAS. When mice were administered high doses of sodium salicylate, which induces tinnitus in humans, there was a significant reduction in GPIAS, consistent with the presence of tinnitus. Thus, measurement of the peak speed or twitch amplitude of pinna, back and tail markers provides a reliable assessment of tinnitus in rodents.
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Affiliation(s)
- Mark N. Wallace
- Hearing Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Joel I. Berger
- Human Brain Research Laboratory, Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, IA, United States
| | - Adam Hockley
- Cognitive and Auditory Neuroscience Laboratory, Institute of Neuroscience of Castilla y León, University of Salamanca, Salamanca, Spain
| | | | - Michael A. Akeroyd
- Hearing Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Alan R. Palmer
- Hearing Sciences, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Peter A. McNaughton
- Wolfson Sensory, Pain and Regeneration Centre, King’s College London, London, United Kingdom
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Ji L, Borges BC, Martel DT, Wu C, Liberman MC, Shore SE, Corfas G. From hidden hearing loss to supranormal auditory processing by neurotrophin 3-mediated modulation of inner hair cell synapse density. PLoS Biol 2024; 22:e3002665. [PMID: 38935589 PMCID: PMC11210788 DOI: 10.1371/journal.pbio.3002665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 05/07/2024] [Indexed: 06/29/2024] Open
Abstract
Loss of synapses between spiral ganglion neurons and inner hair cells (IHC synaptopathy) leads to an auditory neuropathy called hidden hearing loss (HHL) characterized by normal auditory thresholds but reduced amplitude of sound-evoked auditory potentials. It has been proposed that synaptopathy and HHL result in poor performance in challenging hearing tasks despite a normal audiogram. However, this has only been tested in animals after exposure to noise or ototoxic drugs, which can cause deficits beyond synaptopathy. Furthermore, the impact of supernumerary synapses on auditory processing has not been evaluated. Here, we studied mice in which IHC synapse counts were increased or decreased by altering neurotrophin 3 (Ntf3) expression in IHC supporting cells. As we previously showed, postnatal Ntf3 knockdown or overexpression reduces or increases, respectively, IHC synapse density and suprathreshold amplitude of sound-evoked auditory potentials without changing cochlear thresholds. We now show that IHC synapse density does not influence the magnitude of the acoustic startle reflex or its prepulse inhibition. In contrast, gap-prepulse inhibition, a behavioral test for auditory temporal processing, is reduced or enhanced according to Ntf3 expression levels. These results indicate that IHC synaptopathy causes temporal processing deficits predicted in HHL. Furthermore, the improvement in temporal acuity achieved by increasing Ntf3 expression and synapse density suggests a therapeutic strategy for improving hearing in noise for individuals with synaptopathy of various etiologies.
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Affiliation(s)
- Lingchao Ji
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Beatriz C. Borges
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - David T. Martel
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Calvin Wu
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
| | - M. Charles Liberman
- Mass Eye and Ear Infirmary and Harvard Medical School. Boston, Massachusetts, United States of America
| | - Susan E. Shore
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
- Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, United States of America
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gabriel Corfas
- Kresge Hearing Research Institute and Department of Otolaryngology—Head and Neck Surgery, University of Michigan, Ann Arbor, Michigan, United States of America
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Wake N, Shiramatsu TI, Takahashi H. Map plasticity following noise exposure in auditory cortex of rats: implications for disentangling neural correlates of tinnitus and hyperacusis. Front Neurosci 2024; 18:1385942. [PMID: 38881748 PMCID: PMC11176560 DOI: 10.3389/fnins.2024.1385942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 05/16/2024] [Indexed: 06/18/2024] Open
Abstract
Introduction Both tinnitus and hyperacusis, likely triggered by hearing loss, can be attributed to maladaptive plasticity in auditory perception. However, owing to their co-occurrence, disentangling their neural mechanisms proves difficult. We hypothesized that the neural correlates of tinnitus are associated with neural activities triggered by low-intensity tones, while hyperacusis is linked to responses to moderate- and high-intensity tones. Methods To test these hypotheses, we conducted behavioral and electrophysiological experiments in rats 2 to 8 days after traumatic tone exposure. Results In the behavioral experiments, prepulse and gap inhibition tended to exhibit different frequency characteristics (although not reaching sufficient statistical levels), suggesting that exposure to traumatic tones led to acute symptoms of hyperacusis and tinnitus at different frequency ranges. When examining the auditory cortex at the thalamocortical recipient layer, we observed that tinnitus symptoms correlated with a disorganized tonotopic map, typically characterized by responses to low-intensity tones. Neural correlates of hyperacusis were found in the cortical recruitment function at the multi-unit activity (MUA) level, but not at the local field potential (LFP) level, in response to moderate- and high-intensity tones. This shift from LFP to MUA was associated with a loss of monotonicity, suggesting a crucial role for inhibitory synapses. Discussion Thus, in acute symptoms of traumatic tone exposure, our experiments successfully disentangled the neural correlates of tinnitus and hyperacusis at the thalamocortical recipient layer of the auditory cortex. They also suggested that tinnitus is linked to central noise, whereas hyperacusis is associated with aberrant gain control. Further interactions between animal experiments and clinical studies will offer insights into neural mechanisms, diagnosis and treatments of tinnitus and hyperacusis, specifically in terms of long-term plasticity of chronic symptoms.
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Affiliation(s)
- Naoki Wake
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Tomoyo I Shiramatsu
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Hirokazu Takahashi
- Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, Tokyo, Japan
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van den Berg MM, Wong AB, Houtak G, Williamson RS, Borst JGG. Sodium salicylate improves detection of amplitude-modulated sound in mice. iScience 2024; 27:109691. [PMID: 38736549 PMCID: PMC11088340 DOI: 10.1016/j.isci.2024.109691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 01/14/2024] [Accepted: 04/05/2024] [Indexed: 05/14/2024] Open
Abstract
Salicylate is commonly used to induce tinnitus in animals, but its underlying mechanism of action is still debated. We therefore tested its effects on the firing properties of neurons in the mouse inferior colliculus (IC). Salicylate induced a large decrease in the spontaneous activity and an increase of ∼20 dB SPL in the minimum threshold of single units. In response to sinusoidally modulated noise (SAM noise) single units showed both an increase in phase locking and improved rate coding. Mice also became better at detecting amplitude modulations, and a simple threshold model based on the IC population response could reproduce this improvement. The responses to dynamic random chords (DRCs) suggested that the improved AM encoding was due to a linearization of the cochlear output, resulting in larger contrasts during SAM noise. These effects of salicylate are not consistent with the presence of tinnitus, but should be taken into account when studying hyperacusis.
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Affiliation(s)
- Maurits M. van den Berg
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, NL-3015 GD Rotterdam, the Netherlands
| | - Aaron B. Wong
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, NL-3015 GD Rotterdam, the Netherlands
| | - Ghais Houtak
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, NL-3015 GD Rotterdam, the Netherlands
| | - Ross S. Williamson
- Pittsburgh Hearing Research Center, Department of Otolaryngology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - J. Gerard G. Borst
- Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, NL-3015 GD Rotterdam, the Netherlands
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Dai Q, Qu T, Shen G, Wang H. Characterization of the neural circuitry of the auditory thalamic reticular nucleus and its potential role in salicylate-induced tinnitus. Front Neurosci 2024; 18:1368816. [PMID: 38629053 PMCID: PMC11019010 DOI: 10.3389/fnins.2024.1368816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 03/19/2024] [Indexed: 04/19/2024] Open
Abstract
Introduction Subjective tinnitus, the perception of sound without an external acoustic source, is often subsequent to noise-induced hearing loss or ototoxic medications. The condition is believed to result from neuroplastic alterations in the auditory centers, characterized by heightened spontaneous neural activities and increased synchrony due to an imbalance between excitation and inhibition. However, the role of the thalamic reticular nucleus (TRN), a structure composed exclusively of GABAergic neurons involved in thalamocortical oscillations, in the pathogenesis of tinnitus remains largely unexplored. Methods We induced tinnitus in mice using sodium salicylate and assessed tinnitus-like behaviors using the Gap Pre-Pulse Inhibition of the Acoustic Startle (GPIAS) paradigm. We utilized combined viral tracing techniques to identify the neural circuitry involved and employed immunofluorescence and confocal imaging to determine cell types and activated neurons. Results Salicylate-treated mice exhibited tinnitus-like behaviors. Our tracing clearly delineated the inputs and outputs of the auditory-specific TRN. We discovered that chemogenetic activation of the auditory TRN significantly reduced the salicylate-evoked rise in c-Fos expression in the auditory cortex. Discussion This finding posits the TRN as a potential modulatory target for tinnitus treatment. Furthermore, the mapped sensory inputs to the auditory TRN suggest possibilities for employing optogenetic or sensory stimulations to manipulate thalamocortical activities. The precise mapping of the auditory TRN-mediated neural pathways offers a promising avenue for designing targeted interventions to alleviate tinnitus symptoms.
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Affiliation(s)
| | | | - Guoming Shen
- School of Integrated Chinese and Western Medicine, Anhui University of Chinese Medicine, Hefei, China
| | - Haitao Wang
- School of Integrated Chinese and Western Medicine, Anhui University of Chinese Medicine, Hefei, China
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Farhadi M, Gorji A, Mirsalehi M, Poletaev AB, Asadpour A, Mahboudi F, Jafarian M, Farrahizadeh M, Akbarnejad Z, Mahmoudian S. Electrophysiological and molecular changes following neuroprotective placental protein administration on tinnitus-induced rats. Laryngoscope Investig Otolaryngol 2023; 8:1410-1420. [PMID: 37899856 PMCID: PMC10601594 DOI: 10.1002/lio2.1156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/01/2023] [Accepted: 08/16/2023] [Indexed: 10/31/2023] Open
Abstract
Objective Despite 6%-20% of the adult population suffering from tinnitus, there is no standard treatment for it. Placenta extract has been used for various therapeutic purposes, including hearing loss. Here, we evaluate the effect of a novel neuroprotective protein composition (NPPC) extract on electrophysiological and molecular changes in the medial geniculate body (MGB) of tinnitus-induced rats. Methods To evaluate the protein analysis by western blot, the rats were divided into three groups: (1) saline group (intraperitoneal injection of 200 mg/kg saline twice a day for 28 consecutive days, (2) chronic Na-Sal group received sodium salicylate as in the first group, and (3) chronic treatment group (received salicylate 200 mg/kg twice daily for 2 weeks, followed by 0.4 mg NPPC daily from day 14 to day 28). Single-unit recordings were performed on a separate group that was treated as in group 4. Gap-prepulse inhibition of the acoustic startle (GPIAS) and pre-pulse inhibition (PPI) was performed to confirm tinnitus in all groups at the baseline, 14th and 28th days. Results Western blot analysis showed that the expression of γ-Aminobutyric acid Aα1 subunit (GABA Aα1), N-methyl-d-aspartate receptor subtype 2B (NR2B or NMDAR2B), α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors subunit GluR1 (GluR1), and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors subunit GluR2 (GluR2) decreased after Na-Sal injection, while NPPC upregulated their expression. MGB units in rats with tinnitus showed decreased spontaneous firing rate, burst per minute, and a spike in a burst. After NPPC administration, neural activity patterns showed a significant positive effect of NPPC on tinnitus. Conclusion NPPC can play an effective role in the treatment of tinnitus in salicylate-induced rats, and MGB is one of the brain areas involved in these processes. Level of Evidence NA.
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Affiliation(s)
- Mohammad Farhadi
- ENT and Head and Neck Research CenterThe Five Senses Health Institute, School of Medicine, Iran University of Medical SciencesTehranIran
| | - Ali Gorji
- Epilepsy Research Center, Department of NeurosurgeryWestfälische Wilhelms‐Universitat MünsterMünsterGermany
- Neuroscience Research CenterMashhad University of Medical SciencesMashhadIran
- Shefa Neuroscience Research CenterKhatam Alanbia HospitalTehranIran
| | - Marjan Mirsalehi
- ENT and Head and Neck Research CenterThe Five Senses Health Institute, School of Medicine, Iran University of Medical SciencesTehranIran
| | - Alexander Borisovich Poletaev
- Clinical and Research Center of Children Psycho‐NeurologyMoscowRussian Federation
- Medical Research Centre “Immunculus”MoscowRussian Federation
| | - Abdoreza Asadpour
- Intelligent Systems Research CenterUlster University, Magee CampusDerry~LondonderryNorthern IrelandUK
| | | | - Maryam Jafarian
- Brain and Spinal Cord Injury Research CentreNeuroscience Institute, Tehran University of Medical SciencesTehranIran
| | - Maryam Farrahizadeh
- Department of Neuroscience, School of Advanced Technologies in MedicineIran University of Medical SciencesTehranIran
| | - Zeinab Akbarnejad
- ENT and Head and Neck Research CenterThe Five Senses Health Institute, School of Medicine, Iran University of Medical SciencesTehranIran
| | - Saeid Mahmoudian
- ENT and Head and Neck Research CenterThe Five Senses Health Institute, School of Medicine, Iran University of Medical SciencesTehranIran
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Shi L, Palmer K, Wang H, Xu-Friedman MA, Sun W. Low Intensity Noise Exposure Enhanced Auditory Loudness and Temporal Processing by Increasing Excitability of DCN. Neural Plast 2022; 2022:6463355. [PMID: 36452876 PMCID: PMC9705115 DOI: 10.1155/2022/6463355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 08/12/2022] [Accepted: 10/21/2022] [Indexed: 11/23/2022] Open
Abstract
Sound stimulation is generally used for tinnitus and hyperacusis treatment. Recent studies found that long-term noise exposure can change synaptic and firing properties in the central auditory system, which will be detected by the acoustic startle reflex. However, the perceptual consequences of long-term low-intensity sound exposure are indistinct. This study will detect the effects of moderate-level noise exposure (83 dB SPL) on auditory loudness, and temporal processing was evaluated using CBA/CaJ mice. C-Fos staining was used to detect neural activity changes in the central auditory pathway. With two weeks of 83 dB SPL noise exposure (8 hours per day), no persistent threshold shift of the auditory brainstem response (ABR) was identified. On the other hand, noise exposure enhanced the acoustic startle response (ASR) and gap-induced prepulse inhibition significantly (gap-PPI). Low-level noise exposure, according to the findings, can alter temporal acuity. Noise exposure increased the number of c-Fos labeled neurons in the dorsal cochlear nucleus (DCN) and caudal pontine reticular nucleus (PnC) but not at a higher level in the central auditory nuclei. Our results suggested that noise stimulation can change acoustical temporal processing presumably by increasing the excitability of auditory brainstem neurons.
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Affiliation(s)
- Lin Shi
- Department of Otorhinolaryngology, The First Hospital of Dalian Medical University, Dalian, China
- Department of Communicative Disorders and Sciences, Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY, USA
| | - Katie Palmer
- Department of Communicative Disorders and Sciences, Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY, USA
| | - Haolin Wang
- Department of Otorhinolaryngology, The First Hospital of Dalian Medical University, Dalian, China
- Department of General Surgery, The First Hospital of Dalian Medical University, Dalian, China
| | - Matthew A. Xu-Friedman
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Wei Sun
- Department of Communicative Disorders and Sciences, Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY, USA
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Hyperacusis: Loudness Intolerance, Fear, Annoyance and Pain. Hear Res 2022; 426:108648. [DOI: 10.1016/j.heares.2022.108648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/02/2022] [Accepted: 11/07/2022] [Indexed: 11/10/2022]
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Zhang C, Adler HJ, Manohar S, Salvi R, Sun W, Ye M, Hu BH. Galectin-3 protects auditory function in female mice. Hear Res 2022; 424:108602. [PMID: 36103788 DOI: 10.1016/j.heares.2022.108602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/31/2022] [Accepted: 09/03/2022] [Indexed: 11/04/2022]
Abstract
Sex differences in the development of sensorineural hearing loss have been recognized in various inner ear disorders, but the molecular basis for such differences is poorly understood. Autosomal genes have been shown to cause sex differences in disease susceptibility, but many genes exerting sex-dependent effects on auditory function remain to be identified. Galectin-3 (Gal-3), a protein encoded by the autosomal gene Lgals3, is a member of the β-galactoside-binding protein family, and has been linked to multiple biological processes, including immune responses, apoptosis, and cell adhesion. Here, we investigated auditory function and hair cell integrity in Gal-3 knockout (KO, Lgals3-/-) and wild-type (WT, Lgals3+/+) mice from age 1 to 6 months. KO mice show a more rapid age-related increase in ABR thresholds compared to WT mice. Noticeably, the threshold deterioration in female KO mice is significantly greater than in the male KO and WT mice. The ABR threshold elevation manifests over a broad frequency range in female KO mice, whereas the threshold elevations are confined to high frequencies in the male KO and WT mice. Moreover, DPOAE input/output functions reveal a similar pattern of auditory dysfunction, with the female KO mice displaying a significantly greater reduction in DPOAE amplitudes than male KO mice and WT mice of both sexes. Finally, age-related outer hair cell loss is greater for female KO mice compared to male KO mice and WT mice of both sexes. Together, these results indicate that Gal-3 deficiency exacerbates age-related cochlear degeneration and auditory dysfunction in female mice. Our study identifies Gal-3 as a sex-dependent molecule for maintaining female cochlear integrity.
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Affiliation(s)
- Celia Zhang
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Henry J Adler
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Senthilvelan Manohar
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Wei Sun
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Mengxiao Ye
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA
| | - Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
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Olthof BMJ, Lyzwa D, Gartside SE, Rees A. Nitric oxide signalling underlies salicylate-induced increases in neuronal firing in the inferior colliculus: A central mechanism of tinnitus? Hear Res 2022; 424:108585. [DOI: 10.1016/j.heares.2022.108585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 06/17/2022] [Accepted: 07/21/2022] [Indexed: 11/16/2022]
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Scott LL, Lowe AS, Brecht EJ, Franco-Waite L, Walton JP. Small molecule modulation of the large-conductance calcium-activated potassium channel suppresses salicylate-induced tinnitus in mice. Front Neurosci 2022; 16:763855. [PMID: 36090293 PMCID: PMC9453485 DOI: 10.3389/fnins.2022.763855] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 08/04/2022] [Indexed: 11/22/2022] Open
Abstract
Tinnitus is the phantom perception of sound that has no external source. A neurological signature of tinnitus, and the frequently associated hyperacusis, is an imbalance between excitatory and inhibitory activity in the central auditory system (CAS), leading to dysregulated network excitability. The large conductance, calcium-activated potassium (BK) channel is a key player in pre- and post-synaptic excitability through its mediation of K+ currents. Changes in BK channel activity are associated with aberrant network activity in sensory regions of the CNS, raising the possibility that BK channel modulation could regulate activity associated with tinnitus and hyperacusis. To test whether BK channel openers are able to suppress biomarkers of drug-induced tinnitus and hyperacusis, the 1,3,4 oxadiazole BMS-191011 was given to young adult CBA mice that had been administered 250 mg/kg sodium salicylate (SS). Systemic treatment with BMS-191011 reduced behavioral manifestations of SS-induced tinnitus, but not hyperacusis, probed via the gap-in-noise startle response method. Systemic BMS-191011 treatment did not influence SS-induced increases in auditory brainstem response functions, but local application at the inferior colliculus did reverse SS-suppressed spontaneous activity, particularly in the frequency region of the tinnitus percept. Thus, action of BMS-191011 in the inferior colliculus may contribute to the reduction in behaviorally measured tinnitus. Together, these findings support the utility of BK channel openers in reducing central auditory processing changes associated with the formation of the tinnitus percept.
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Affiliation(s)
| | - Andrea S. Lowe
- Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL, United States
| | - Elliott J. Brecht
- Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL, United States
| | - Luis Franco-Waite
- Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL, United States
| | - Joseph P. Walton
- Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL, United States
- Department of Communication Sciences and Disorders, University of South Florida, Tampa, FL, United States
- *Correspondence: Joseph P. Walton,
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Behavioral and Immunohistochemical Evidence for Suppressive Effects of Goshajinkigan on Salicylate-Induced Tinnitus in Rats. Brain Sci 2022; 12:brainsci12050587. [PMID: 35624974 PMCID: PMC9139011 DOI: 10.3390/brainsci12050587] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 04/25/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023] Open
Abstract
Many people are affected by tinnitus, a sensation of ringing in the ear despite the absence of external sound. Goshajinkigan (GJG) is one of the formulations of Japanese traditional herbal medicine and is prescribed for the palliative treatment of patients with tinnitus. Although GJG is clinically effective in these patients, its behavioral effects and the underlying neuroanatomical substrate have not been modeled in animals. We modeled tinnitus using salicylate-treated rats, demonstrated the effectiveness of GJG on tinnitus, and examined the underlying neuronal substrate with c-Fos expression. Intraperitoneal injection of sodium salicylate (400 mg/kg) into rats for three consecutive days significantly increased false positive scores, which were used to assess tinnitus behavior. When GJG was orally administered one hour after each salicylate injection, the increase in tinnitus behavior was suppressed. The analysis of c-Fos expression in auditory-related brain areas revealed that GJG significantly reduced the salicylate-induced increase in the number of c-Fos-expressing cells in the auditory cortices, inferior colliculus, and dorsal cochlear nucleus. These results suggest a suppressive effect of GJG on salicylate-induced tinnitus in animal models.
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Zhang C, Ding D, Sun W, Hu BH, Manohar S, Salvi R. Time- and frequency-dependent changes in acoustic startle reflex amplitude following cyclodextrin-induced outer and inner cell loss. Hear Res 2022; 415:108441. [DOI: 10.1016/j.heares.2022.108441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 01/04/2022] [Accepted: 01/13/2022] [Indexed: 11/27/2022]
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The role of the medial geniculate body of the thalamus in the pathophysiology of tinnitus and implications for treatment. Brain Res 2022; 1779:147797. [DOI: 10.1016/j.brainres.2022.147797] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 11/25/2021] [Accepted: 01/13/2022] [Indexed: 01/12/2023]
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Current topics in hearing research: Deafferentation and threshold independent hearing loss. Hear Res 2021; 419:108408. [PMID: 34955321 DOI: 10.1016/j.heares.2021.108408] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 11/20/2022]
Abstract
Hearing research findings in recent years have begun to change how we think about hearing loss and how we consider the risk of auditory damage from noise exposure. These findings include evidence of noise-induced cochlear damage in the absence of corresponding permanent threshold elevation or evidence of hair cell loss. Animal studies in several species have shown that noise exposures that produce robust but only temporary threshold shifts can permanently damage inner hair cell synaptic ribbons. This type of synaptic degeneration has also been shown to occur as a result of aging in animals and humans. The emergence of these data has motivated a number of clinical studies aimed at identifying the perceptual correlates associated with synaptopathy. The deficits believed to arise from synaptopathy include poorer hearing in background noise, tinnitus and hyperacusis (loudness intolerance). However, the findings from human studies have been mixed. Key questions remain as to whether synaptopathy reliably produces suprathreshold perceptual deficits or whether it serves as an early indicator of auditory damage with suprathreshold deficits emerging later as a function of further cochlear damage. Here, we provide an overview of both human and animal studies that explore the relationship among inner hair cell damage, including loss of afferent synapses, auditory thresholds, and suprathreshold measures of hearing.
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16
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Salvi R, Radziwon K, Manohar S, Auerbach B, Ding D, Liu X, Lau C, Chen YC, Chen GD. Review: Neural Mechanisms of Tinnitus and Hyperacusis in Acute Drug-Induced Ototoxicity. Am J Audiol 2021; 30:901-915. [PMID: 33465315 DOI: 10.1044/2020_aja-20-00023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Purpose Tinnitus and hyperacusis are debilitating conditions often associated with age-, noise-, and drug-induced hearing loss. Because of their subjective nature, the neural mechanisms that give rise to tinnitus and hyperacusis are poorly understood. Over the past few decades, considerable progress has been made in deciphering the biological bases for these disorders using animal models. Method Important advances in understanding the biological bases of tinnitus and hyperacusis have come from studies in which tinnitus and hyperacusis are consistently induced with a high dose of salicylate, the active ingredient in aspirin. Results Salicylate induced a transient hearing loss characterized by a reduction in otoacoustic emissions, a moderate cochlear threshold shift, and a large reduction in the neural output of the cochlea. As the weak cochlear neural signals were relayed up the auditory pathway, they were progressively amplified so that the suprathreshold neural responses in the auditory cortex were much larger than normal. Excessive central gain (neural amplification), presumably resulting from diminished inhibition, is believed to contribute to hyperacusis and tinnitus. Salicylate also increased corticosterone stress hormone levels. Functional imaging studies indicated that salicylate increased spontaneous activity and enhanced functional connectivity between structures in the central auditory pathway and regions of the brain associated with arousal (reticular formation), emotion (amygdala), memory/spatial navigation (hippocampus), motor planning (cerebellum), and motor control (caudate/putamen). Conclusion These results suggest that tinnitus and hyperacusis arise from aberrant neural signaling in a complex neural network that includes both auditory and nonauditory structures.
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Affiliation(s)
- Richard Salvi
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Kelly Radziwon
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Senthilvelan Manohar
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Ben Auerbach
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Dalian Ding
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Xiaopeng Liu
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
| | - Condon Lau
- Department of Physics, City University of Hong Kong
| | - Yu-Chen Chen
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, China
| | - Guang-Di Chen
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, The State University of New York at Buffalo
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17
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Patro C, Kreft HA, Wojtczak M. The search for correlates of age-related cochlear synaptopathy: Measures of temporal envelope processing and spatial release from speech-on-speech masking. Hear Res 2021; 409:108333. [PMID: 34425347 PMCID: PMC8424701 DOI: 10.1016/j.heares.2021.108333] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 07/17/2021] [Accepted: 08/04/2021] [Indexed: 01/13/2023]
Abstract
Older adults often experience difficulties understanding speech in adverse listening conditions. It has been suggested that for listeners with normal and near-normal audiograms, these difficulties may, at least in part, arise from age-related cochlear synaptopathy. The aim of this study was to assess if performance on auditory tasks relying on temporal envelope processing reveal age-related deficits consistent with those expected from cochlear synaptopathy. Listeners aged 20 to 66 years were tested using a series of psychophysical, electrophysiological, and speech-perception measures using stimulus configurations that promote coding by medium- and low-spontaneous-rate auditory-nerve fibers. Cognitive measures of executive function were obtained to control for age-related cognitive decline. Results from the different tests were not significantly correlated with each other despite a presumed reliance on common mechanisms involved in temporal envelope processing. Only gap-detection thresholds for a tone in noise and spatial release from speech-on-speech masking were significantly correlated with age. Increasing age was related to impaired cognitive executive function. Multivariate regression analyses showed that individual differences in hearing sensitivity, envelope-based measures, and scores from nonauditory cognitive tests did not significantly contribute to the variability in spatial release from speech-on-speech masking for small target/masker spatial separation, while age was a significant contributor.
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Affiliation(s)
- Chhayakanta Patro
- Department of Psychology, University of Minnesota, N640 Elliott Hall, 75 East River Parkway, Minneapolis, MN 55455, USA.
| | - Heather A Kreft
- Department of Psychology, University of Minnesota, N640 Elliott Hall, 75 East River Parkway, Minneapolis, MN 55455, USA
| | - Magdalena Wojtczak
- Department of Psychology, University of Minnesota, N640 Elliott Hall, 75 East River Parkway, Minneapolis, MN 55455, USA
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18
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Koops EA, Eggermont JJ. The thalamus and tinnitus: Bridging the gap between animal data and findings in humans. Hear Res 2021; 407:108280. [PMID: 34175683 DOI: 10.1016/j.heares.2021.108280] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/26/2021] [Accepted: 05/27/2021] [Indexed: 12/16/2022]
Abstract
The neuronal mechanisms underlying tinnitus are yet to be revealed. Tinnitus, an auditory phantom sensation, used to be approached as a purely auditory domain symptom. More recently, the modulatory impact of non-auditory brain regions on the percept and burden of tinnitus are explored. The thalamus is uniquely situated to facilitate the communication between auditory and non-auditory subcortical and cortical structures. Traditionally, animal models of tinnitus have focussed on subcortical auditory structures, and research with human participants has been concerned with cortical activity in auditory and non-auditory areas. Recently, both research fields have investigated the connectivity between subcortical and cortical regions and between auditory and non-auditory areas. We show that even though the different fields employ different methods to investigate the activity and connectivity of brain areas, there is consistency in the results on tinnitus between these different approaches. This consistency between human and animals research is observed for tinnitus with peripherally instigated hearing damage, and for results obtained with salicylate and noise-induced tinnitus. The thalamus integrates input from limbic and prefrontal areas and modulates auditory activity via its connections to both subcortical and cortical auditory areas. Reported altered activity and connectivity of the auditory, prefrontal, and limbic regions suggest a more systemic approach is necessary to understand the origins and impact of tinnitus.
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Affiliation(s)
- Elouise A Koops
- Department of Otorhinolaryngology/Head and Neck Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
| | - Jos J Eggermont
- Departments of Physiology and Pharmacology, and Psychology, University of Calgary, Calgary, Alberta, Canada
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19
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Herrmann B, Butler BE. Hearing loss and brain plasticity: the hyperactivity phenomenon. Brain Struct Funct 2021; 226:2019-2039. [PMID: 34100151 DOI: 10.1007/s00429-021-02313-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 06/03/2021] [Indexed: 12/22/2022]
Abstract
Many aging adults experience some form of hearing problems that may arise from auditory peripheral damage. However, it has been increasingly acknowledged that hearing loss is not only a dysfunction of the auditory periphery but also results from changes within the entire auditory system, from periphery to cortex. Damage to the auditory periphery is associated with an increase in neural activity at various stages throughout the auditory pathway. Here, we review neurophysiological evidence of hyperactivity, auditory perceptual difficulties that may result from hyperactivity, and outline open conceptual and methodological questions related to the study of hyperactivity. We suggest that hyperactivity alters all aspects of hearing-including spectral, temporal, spatial hearing-and, in turn, impairs speech comprehension when background sound is present. By focusing on the perceptual consequences of hyperactivity and the potential challenges of investigating hyperactivity in humans, we hope to bring animal and human electrophysiologists closer together to better understand hearing problems in older adulthood.
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Affiliation(s)
- Björn Herrmann
- Rotman Research Institute, Baycrest, Toronto, ON, M6A 2E1, Canada. .,Department of Psychology, University of Toronto, Toronto, ON, Canada.
| | - Blake E Butler
- Department of Psychology & The Brain and Mind Institute, University of Western Ontario, London, ON, Canada.,National Centre for Audiology, University of Western Ontario, London, ON, Canada
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20
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Williams ZJ, He JL, Cascio CJ, Woynaroski TG. A review of decreased sound tolerance in autism: Definitions, phenomenology, and potential mechanisms. Neurosci Biobehav Rev 2021; 121:1-17. [PMID: 33285160 PMCID: PMC7855558 DOI: 10.1016/j.neubiorev.2020.11.030] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 12/23/2022]
Abstract
Atypical behavioral responses to environmental sounds are common in autistic children and adults, with 50-70 % of this population exhibiting decreased sound tolerance (DST) at some point in their lives. This symptom is a source of significant distress and impairment across the lifespan, contributing to anxiety, challenging behaviors, reduced community participation, and school/workplace difficulties. However, relatively little is known about its phenomenology or neurocognitive underpinnings. The present article synthesizes a large body of literature on the phenomenology and pathophysiology of DST-related conditions to generate a comprehensive theoretical account of DST in autism. Notably, we argue against conceptualizing DST as a unified construct, suggesting that it be separated into three phenomenologically distinct conditions: hyperacusis (the perception of everyday sounds as excessively loud or painful), misophonia (an acquired aversive reaction to specific sounds), and phonophobia (a specific phobia of sound), each responsible for a portion of observed DST behaviors. We further elaborate our framework by proposing preliminary neurocognitive models of hyperacusis, misophonia, and phonophobia that incorporate neurophysiologic findings from studies of autism.
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Affiliation(s)
- Zachary J Williams
- Medical Scientist Training Program, Vanderbilt University School of Medicine, 221 Eskind Biomedical Library and Learning Center, 2209 Garland Ave., Nashville, TN, 37240, United States; Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, 1215 21st Avenue South, Medical Center East, Room 8310, Nashville, TN, 37232, United States; Vanderbilt Brain Institute, Vanderbilt University, 7203 Medical Research Building III, 465 21st Avenue South, Nashville, TN, 37232, United States; Frist Center for Autism and Innovation, Vanderbilt University, 2414 Highland Avenue, Suite 115, Nashville, TN, 37212, United States.
| | - Jason L He
- Department of Forensic and Neurodevelopmental Sciences, Sackler Institute for Translational Neurodevelopment, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Strand Building, Strand Campus, Strand, London, WC2R 2LS, London, United Kingdom.
| | - Carissa J Cascio
- Vanderbilt Brain Institute, Vanderbilt University, 7203 Medical Research Building III, 465 21st Avenue South, Nashville, TN, 37232, United States; Frist Center for Autism and Innovation, Vanderbilt University, 2414 Highland Avenue, Suite 115, Nashville, TN, 37212, United States; Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, 2254 Village at Vanderbilt, 1500 21st Ave South, Nashville, TN, 37212, United States; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, 110 Magnolia Cir, Nashville, TN, 37203, United States.
| | - Tiffany G Woynaroski
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, 1215 21st Avenue South, Medical Center East, Room 8310, Nashville, TN, 37232, United States; Vanderbilt Brain Institute, Vanderbilt University, 7203 Medical Research Building III, 465 21st Avenue South, Nashville, TN, 37232, United States; Frist Center for Autism and Innovation, Vanderbilt University, 2414 Highland Avenue, Suite 115, Nashville, TN, 37212, United States; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, 110 Magnolia Cir, Nashville, TN, 37203, United States.
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21
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Metabolic changes in the brain and blood of rats following acoustic trauma, tinnitus and hyperacusis. PROGRESS IN BRAIN RESEARCH 2021; 262:399-430. [PMID: 33931189 DOI: 10.1016/bs.pbr.2020.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
It has been increasingly recognized that tinnitus is likely to be generated by complex network changes. Acoustic trauma that causes tinnitus induces significant changes in multiple metabolic pathways in the brain. However, it is not clear whether those metabolic changes in the brain could also be reflected in blood samples and whether metabolic changes could discriminate acoustic trauma, hyperacusis and tinnitus. We analyzed brain and serum metabolic changes in rats following acoustic trauma or a sham procedure using metabolomics. Hearing levels were recorded before and after acoustic trauma and behavioral measures to quantify tinnitus and hyperacusis were conducted at 4 weeks following acoustic trauma. Tissues from 11 different brain regions and serum samples were collected at about 3 months following acoustic trauma. Among the acoustic trauma animals, eight exhibited hyperacusis-like behavior and three exhibited tinnitus-like behavior. Using Gas chromatography-mass spectrometry and multivariate statistical analysis, significant metabolic changes were found in acoustic trauma animals in both the brain and serum samples with a number of metabolic pathways significantly perturbated. Furthermore, metabolic changes in the serum were able to differentiate sham from acoustic trauma animals, as well as sham from hyperacusis animals, with high accuracy. Our results suggest that serum metabolic profiling in combination with machine learning analysis may be a promising approach for identifying biomarkers for acoustic trauma, hyperacusis and potentially, tinnitus.
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22
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Lu J, West MB, Du X, Cai Q, Ewert DL, Cheng W, Nakmali D, Li W, Huang X, Kopke RD. Electrophysiological assessment and pharmacological treatment of blast-induced tinnitus. PLoS One 2021; 16:e0243903. [PMID: 33411811 PMCID: PMC7790300 DOI: 10.1371/journal.pone.0243903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 12/01/2020] [Indexed: 11/19/2022] Open
Abstract
Tinnitus, the phantom perception of sound, often occurs as a clinical sequela of auditory traumas. In an effort to develop an objective test and therapeutic approach for tinnitus, the present study was performed in blast-exposed rats and focused on measurements of auditory brainstem responses (ABRs), prepulse inhibition of the acoustic startle response, and presynaptic ribbon densities on cochlear inner hair cells (IHCs). Although the exact mechanism is unknown, the “central gain theory” posits that tinnitus is a perceptual indicator of abnormal increases in the gain (or neural amplification) of the central auditory system to compensate for peripheral loss of sensory input from the cochlea. Our data from vehicle-treated rats supports this rationale; namely, blast-induced cochlear synaptopathy correlated with imbalanced elevations in the ratio of centrally-derived ABR wave V amplitudes to peripherally-derived wave I amplitudes, resulting in behavioral evidence of tinnitus. Logistic regression modeling demonstrated that the ABR wave V/I amplitude ratio served as a reliable metric for objectively identifying tinnitus. Furthermore, histopathological examinations in blast-exposed rats revealed tinnitus-related changes in the expression patterns of key plasticity factors in the central auditory pathway, including chronic loss of Arc/Arg3.1 mobilization. Using a formulation of N-acetylcysteine (NAC) and disodium 2,4-disulfophenyl-N-tert-butylnitrone (HPN-07) as a therapeutic for addressing blast-induced neurodegeneration, we measured a significant treatment effect on preservation or restoration of IHC ribbon synapses, normalization of ABR wave V/I amplitude ratios, and reduced behavioral evidence of tinnitus in blast-exposed rats, all of which accorded with mitigated histopathological evidence of tinnitus-related neuropathy and maladaptive neuroplasticity.
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Affiliation(s)
- Jianzhong Lu
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Matthew B. West
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Xiaoping Du
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Qunfeng Cai
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Donald L. Ewert
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Weihua Cheng
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Don Nakmali
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Wei Li
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Xiangping Huang
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
| | - Richard D. Kopke
- Hough Ear Institute, Oklahoma City, Oklahoma, United States of America
- Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- Departments of Physiology and Otolaryngology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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23
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Jeschke M, Happel MFK, Tziridis K, Krauss P, Schilling A, Schulze H, Ohl FW. Acute and Long-Term Circuit-Level Effects in the Auditory Cortex After Sound Trauma. Front Neurosci 2021; 14:598406. [PMID: 33469416 PMCID: PMC7813782 DOI: 10.3389/fnins.2020.598406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/02/2020] [Indexed: 12/31/2022] Open
Abstract
Harmful environmental sounds are a prevailing source of chronic hearing impairments, including noise induced hearing loss, hyperacusis, or tinnitus. How these symptoms are related to pathophysiological damage to the sensory receptor epithelia and its effects along the auditory pathway, have been documented in numerous studies. An open question concerns the temporal evolution of maladaptive changes after damage and their manifestation in the balance of thalamocortical and corticocortical input to the auditory cortex (ACx). To address these issues, we investigated the loci of plastic reorganizations across the tonotopic axis of the auditory cortex of male Mongolian gerbils (Meriones unguiculatus) acutely after a sound trauma and after several weeks. We used a residual current-source density analysis to dissociate adaptations of intracolumnar input and horizontally relayed corticocortical input to synaptic populations across cortical layers in ACx. A pure tone-based sound trauma caused acute changes of subcortical inputs and corticocortical inputs at all tonotopic regions, particularly showing a broad reduction of tone-evoked inputs at tonotopic regions around the trauma frequency. At other cortical sites, the overall columnar activity acutely decreased, while relative contributions of lateral corticocortical inputs increased. After 4-6 weeks, cortical activity in response to the altered sensory inputs showed a general increase of local thalamocortical input reaching levels higher than before the trauma. Hence, our results suggest a detailed mechanism for overcompensation of altered frequency input in the auditory cortex that relies on a changing balance of thalamocortical and intracortical input and along the frequency gradient of the cortical tonotopic map.
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Affiliation(s)
- Marcus Jeschke
- Leibniz Institute for Neurobiology (LIN), Magdeburg, Germany
- Institute of Biology (IBIO), Otto-von-Guericke University Magdeburg (OVGU), Magdeburg, Germany
- Cognitive Hearing in Primates Group, Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany
- Institute for Auditory Neuroscience Göttingen, University Medical Center, Göttingen, Germany
| | - Max F. K. Happel
- Leibniz Institute for Neurobiology (LIN), Magdeburg, Germany
- Institute of Biology (IBIO), Otto-von-Guericke University Magdeburg (OVGU), Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Konstantin Tziridis
- Experimental Otolaryngology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Patrick Krauss
- Experimental Otolaryngology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Achim Schilling
- Experimental Otolaryngology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Holger Schulze
- Experimental Otolaryngology, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Frank W. Ohl
- Leibniz Institute for Neurobiology (LIN), Magdeburg, Germany
- Institute of Biology (IBIO), Otto-von-Guericke University Magdeburg (OVGU), Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
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24
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Fournier P, Hébert S. The gap prepulse inhibition of the acoustic startle (GPIAS) paradigm to assess auditory temporal processing: Monaural versus binaural presentation. Psychophysiology 2020; 58:e13755. [PMID: 33355931 DOI: 10.1111/psyp.13755] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 01/20/2023]
Abstract
The Gap Prepulse Inhibition of the Acoustic Startle Reflex (GPIAS) is a paradigm used to assess auditory temporal processing in both animals and humans. It consists of the presentation of a silent gap embedded in noise and presented a few milliseconds before a startle sound. The silent gap produces the inhibition of the startle reflex, a phenomenon called gap-prepulse inhibition (GPI). This paradigm is also used to detect tinnitus in animal models. The lack of inhibition by the silent gaps is suggested to be indicative of the presence of tinnitus "filling-in" the gaps. The current research aims at improving the GPIAS technique by comparing the GPI produced by monaural versus binaural silent gaps in 29 normal-hearing subjects. Two gap durations (5 or 50 ms), each embedded in two different frequency backgrounds (centered around 500 or 4 kHz). Both low- and high- frequency narrowband noises had a bandwidth of half an octave. Overall, the startle magnitude was greater for the binaural versus the monaural presentation, which might reflect binaural loudness summation. In addition, the GPI was similar between the monaural and the binaural presentations for the high-frequency background noise. However, the GPI was greater for the low-frequency background noise for the binaural, compared to the monaural, presentation. These findings suggest that monaural GPIAS might be more suited to detect tinnitus compared to the binaural presentation.
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Affiliation(s)
- Philippe Fournier
- École d'orthophonie et d'audiologie, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada.,BRAMS, International Laboratory for Brain, Music, and Sound Research, Université de Montréal and McGill University, Montréal, QC, Canada.,Centre national de la recherche scientifique (CNRS), Université d'Aix-Marseille, Centre St-Charles-Pôle 3C, Marseille, France
| | - Sylvie Hébert
- École d'orthophonie et d'audiologie, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada.,BRAMS, International Laboratory for Brain, Music, and Sound Research, Université de Montréal and McGill University, Montréal, QC, Canada
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25
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Hayes SH, Schormans AL, Sigel G, Beh K, Herrmann B, Allman BL. Uncovering the contribution of enhanced central gain and altered cortical oscillations to tinnitus generation. Prog Neurobiol 2020; 196:101893. [PMID: 32783988 DOI: 10.1016/j.pneurobio.2020.101893] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/20/2020] [Accepted: 08/02/2020] [Indexed: 12/22/2022]
Abstract
Various theories and their associated mechanisms have been proposed as the neural basis of phantom sound perception (tinnitus), including central gain enhancement and altered cortical oscillations. However, it remains unknown whether these cortical changes directly cause tinnitus, or simply coexist with the phantom percept. Using chronically-implanted electrodes and drug delivery cannulae in rats, we examined whether enhanced central gain and cortical oscillations are consistent across different tinnitus induction methods (noise exposure; salicylate), and if directly-inducing enhanced central gain or altered cortical oscillations via pharmacologic manipulation of inhibition along the auditory pathway would cause behavioral evidence of tinnitus. We show that, while there appeared to be no clear link between tinnitus and the presence of enhanced sound-evoked cortical activity or altered spontaneous cortical oscillations, pharmacologic impairment of GABAergic neurotransmission in the auditory cortex was sufficient to cause tinnitus; collective findings which further advance our understanding of the neural basis of tinnitus.
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Affiliation(s)
- Sarah H Hayes
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, N6A 3K7, Canada.
| | - Ashley L Schormans
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Gregory Sigel
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Krystal Beh
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Björn Herrmann
- Department of Psychology, Brain and Mind Institute, The University of Western Ontario, London, ON, N6A 3K7, Canada
| | - Brian L Allman
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, ON, N6A 3K7, Canada
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26
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Mechanisms and Functional Consequences of Presynaptic Homeostatic Plasticity at Auditory Nerve Synapses. J Neurosci 2020; 40:6896-6909. [PMID: 32747441 DOI: 10.1523/jneurosci.1175-19.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 07/24/2020] [Accepted: 07/28/2020] [Indexed: 01/21/2023] Open
Abstract
Multiple forms of homeostasis influence synaptic function under diverse activity conditions. Both presynaptic and postsynaptic forms of homeostasis are important, but their relative impact on fidelity is unknown. To address this issue, we studied auditory nerve synapses onto bushy cells in the cochlear nucleus of mice of both sexes. These synapses undergo bidirectional presynaptic and postsynaptic homeostatic changes with increased and decreased acoustic stimulation. We found that both young and mature synapses exhibit similar activity-dependent changes in short-term depression. Experiments using chelators and imaging both indicated that presynaptic Ca2+ influx decreased after noise exposure, and increased after ligating the ear canal. By contrast, Ca2+ cooperativity was unaffected. Experiments using specific antagonists suggest that occlusion leads to changes in the Ca2+ channel subtypes driving neurotransmitter release. Furthermore, dynamic-clamp experiments revealed that spike fidelity primarily depended on changes in presynaptic depression, with some contribution from changes in postsynaptic intrinsic properties. These experiments indicate that presynaptic Ca2+ influx is homeostatically regulated in vivo to enhance synaptic fidelity.SIGNIFICANCE STATEMENT Homeostatic mechanisms in synapses maintain stable function in the face of different levels of activity. Both juvenile and mature auditory nerve synapses onto bushy cells modify short-term depression in different acoustic environments, which raises the question of what the underlying presynaptic mechanisms are and the relative importance of presynaptic and postsynaptic contributions to the faithful transfer of information. Changes in short-term depression under different acoustic conditions were a result of changes in presynaptic Ca2+ influx. Spike fidelity was affected by both presynaptic and postsynaptic changes after ear occlusion and was only affected by presynaptic changes after noise-rearing. These findings are important for understanding regulation of auditory synapses under normal conditions and also in disorders following noise exposure or conductive hearing loss.
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Manohar S, Adler HJ, Radziwon K, Salvi R. Interaction of auditory and pain pathways: Effects of stimulus intensity, hearing loss and opioid signaling. Hear Res 2020; 393:108012. [PMID: 32554129 DOI: 10.1016/j.heares.2020.108012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 04/24/2020] [Accepted: 05/29/2020] [Indexed: 11/19/2022]
Abstract
Moderate intensity sounds can reduce pain sensitivity (i.e., audio-analgesia) whereas intense sounds can induce aural pain, evidence of multisensory interaction between auditory and pain pathways. To explore auditory-pain pathway interactions, we used the tail-flick (TF) test to assess thermal tail-pain sensitivity by measuring the latency of a rat to remove its tail from 52 °C water. In Experiment 1, TF latencies were measured in ambient noise and broadband noise (BBN) presented from 80 to 120 dB SPL. TF latencies gradually increased from ambient to 90 dB SPL (audio-analgesia), but then declined. At 120 dB, TF latencies were significantly shorter than normal, evidence for audio-hyperalgesia near the aural threshold for pain. In Experiment II, the opioid pain pathway was modified by treating rats with a high dose of fentanyl known to induce post-treatment hyperalgesia. TF latencies in ambient noise were normal 10-days post-fentanyl. However, TF latencies became shorter than normal from 90 to 110 dB indicating that fentanyl pre-treatment had converted audio-analgesia to audio-hyperalgesia. In Experiment III, we tested the hypothesis that hearing loss could alter pain sensitivity by unilaterally exposing rats to an intense noise that induced a significant hearing loss. TF latencies in ambient noise gradually declined from 1- to 4-weeks post-exposure indicating that noise-induced hearing loss had increased pain sensitivity. Our results suggest that auditory and pain pathways interact in ways that depend on intensity, hearing loss and opioid pain signaling, results potentially relevant to pain hyperacusis.
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Affiliation(s)
- Senthilvelan Manohar
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY, 14214, USA
| | - Henry J Adler
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY, 14214, USA
| | - Kelly Radziwon
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY, 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, 137 Cary Hall, University at Buffalo, Buffalo, NY, 14214, USA.
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Karimi M, Nasirinezhad F, Shahbazi A, Jalaei S, Mokrian H, Farahani S. The effect of insular cortex lesion on hyperacusis-like behavior in rats. Int J Neurosci 2020; 130:1071-1081. [PMID: 32003272 DOI: 10.1080/00207454.2020.1716751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background and objectives: Hyperacusis is hypersensitivity and extreme response to the intensity of sound that is tolerable in normal subjects. The mechanisms underlying hyperacusis has not been well understood, specially the role of insular cortex. The aim of this study is to investigate the role of insular cortex in hyperacusis like behavior. Material and methods: The number of 33 male wistar rats weighting 170-250 gr were allocated randomly in three groups; control, sham, and insular lesion. Auditory startle responses (ASR) to different intensities of stimuli (70, 80, 90, 100, and110 dB without background noise as well as 110 dB in the presence of 70, 80 dB background noise) were measured before and up to four weeks after intervention. Results: Data analyses showed an increase in ASR to 100 dB stimulus without background noise one week after insular lesion, and increased responses to other intensities two weeks after lesion. Furthermore, there was a decrease in ASR to 110 dB stimulus with 80 dB background noise two weeks after insular lesion. However, no significant difference was observed in 70 dB background noise. The changes in ASR lasts at least four weeks.Conclusion: The findings indicated that there was an increase in ASR in the absence of background noise following cortical excititoxic lesion limited to insular cortex, while there was a decrease in responses in the presence of background noise which suggests possible increased sensitivity to sound loudness as a hyperacusis-like phenomenon. The study showed a significant relationship between insular cortex lesion and ASR in rats.
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Affiliation(s)
- Minoo Karimi
- Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran
| | - Farinaz Nasirinezhad
- Physiology Research Center, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.,Department of Physiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Ali Shahbazi
- Cellular and Molecular Research Center, Iran University of Medical Science, Tehran, Iran.,Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran Iran
| | - Shohreh Jalaei
- Department of Physiotherapy, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran
| | - Helnaz Mokrian
- Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran
| | - Saeid Farahani
- Department of Audiology, School of Rehabilitation, Tehran University of Medical Sciences, Tehran, Iran
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Eggermont JJ. Separate auditory pathways for the induction and maintenance of tinnitus and hyperacusis? PROGRESS IN BRAIN RESEARCH 2020; 260:101-127. [PMID: 33637214 DOI: 10.1016/bs.pbr.2020.01.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tinnitus and hyperacusis often occur together, however tinnitus may occur without hyperacusis or hyperacusis without tinnitus. Based on animal research one could argue that hyperacusis results from noise exposures that increase central gain in the lemniscal, tonotopically organized, pathways, whereas tinnitus requires increased burst firing and neural synchrony in the extra-lemniscal pathway. However, these substrates are not sufficient and require involvement of the central nervous system. The dominant factors in changing cortical networks in tinnitus patients are foremost the degree and type of hearing loss, and comorbidities such as distress and mood. So far, no definite changes have been established for tinnitus proper, albeit that changes in connectivity between the dorsal attention network and the parahippocampal area, as well as the default-mode network-precuneus decoupling, appear to be strong candidates. I conclude that there is still a strong need for further integrating animal and human research into tinnitus and hyperacusis.
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Affiliation(s)
- Jos J Eggermont
- Department of Psychology, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada.
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Wong E, Radziwon K, Chen GD, Liu X, Manno FA, Manno SH, Auerbach B, Wu EX, Salvi R, Lau C. Functional magnetic resonance imaging of enhanced central auditory gain and electrophysiological correlates in a behavioral model of hyperacusis. Hear Res 2020; 389:107908. [PMID: 32062293 DOI: 10.1016/j.heares.2020.107908] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/02/2019] [Accepted: 02/02/2020] [Indexed: 01/24/2023]
Abstract
Hyperacusis is a debilitating hearing condition in which normal everyday sounds are perceived as exceedingly loud, annoying, aversive or even painful. The prevalence of hyperacusis approaches 10%, making it an important, but understudied medical condition. To noninvasively identify the neural correlates of hyperacusis in an animal model, we used sound-evoked functional magnetic resonance imaging (fMRI) to locate regions of abnormal activity in the central nervous system of rats with behavioral evidence of hyperacusis induced with an ototoxic drug (sodium salicylate, 250 mg/kg, i.p.). Reaction time-intensity measures of loudness-growth revealed behavioral evidence of salicylate-induced hyperacusis at high intensities. fMRI revealed significantly enhanced sound-evoked responses in the auditory cortex (AC) to 80 dB SPL tone bursts presented at 8 and 16 kHz. Sound-evoked responses in the inferior colliculus (IC) were also enhanced, but to a lesser extent. To confirm the main results, electrophysiological recordings of spike discharges from multi-unit clusters were obtained from the central auditory pathway. Salicylate significantly enhanced tone-evoked spike-discharges from multi-unit clusters in the AC from 4 to 30 kHz at intensities ≥60 dB SPL; less enhancement occurred in the medial geniculate body (MGB), and even less in the IC. Our results demonstrate for the first time that non-invasive sound-evoked fMRI can be used to identify regions of neural hyperactivity throughout the brain in an animal model of hyperacusis.
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Affiliation(s)
- Eddie Wong
- Department of Physics, City University of Hong Kong, Hong Kong, China; Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China; Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China
| | - Kelly Radziwon
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Guang-Di Chen
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Xiaopeng Liu
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Francis Am Manno
- Department of Physics, City University of Hong Kong, Hong Kong, China; School of Biomedical Engineering, University of Sydney, Sydney, New South Wales, Australia
| | - Sinai Hc Manno
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Benjamin Auerbach
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA
| | - Ed X Wu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, China; Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, China
| | - Richard Salvi
- Center for Hearing & Deafness, Department of Communicative Disorders and Sciences, SUNY at Buffalo, 137 Cary Hall, Buffalo, NY, 14214, USA; Department of Audiology and Speech-Language Pathology, Asia University, Taichung, Taiwan, ROC.
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Hong Kong, China.
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Winne J, Boerner BC, Malfatti T, Brisa E, Doerl J, Nogueira I, Leão KE, Leão RN. Anxiety-like behavior induced by salicylate depends on age and can be prevented by a single dose of 5-MeO-DMT. Exp Neurol 2020; 326:113175. [PMID: 31923390 DOI: 10.1016/j.expneurol.2020.113175] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/23/2019] [Accepted: 01/06/2020] [Indexed: 11/16/2022]
Abstract
Salicylate intoxication is a cause of tinnitus and comorbidly associated with anxiety in humans. In a previous work, we showed that salicylate induces anxiety-like behavior and hippocampal type 2 theta oscillations (theta2) in mice. Here we investigate if the anxiogenic effect of salicylate is dependent on age and previous tinnitus experience. We also tested whether a single dose of DMT can prevent this effect. Using microwire electrode arrays, we recorded local field potential in young (4-5- month-old) and old (11-13-month-old) mice to study the electrophysiological effect of tinnitus in the ventral hippocampus (vHipp) and medial prefrontal cortex (mPFC) in an open field arena and elevated plus maze 1h after salicylate (300mg/kg) injection. We found that anxiety-like behavior and increase in theta2 oscillations (4-6 Hz), following salicylate pre-treatment, only occurs in young (normal hearing) mice. We also show that theta2 and slow gamma oscillations increase in the vHipp and mPFC in a complementary manner during anxiety tests in the presence of salicylate. Finally, we show that pre-treating mice with a single dose of the hallucinogenic 5-MeO-DMT prevents anxiety-like behavior and the increase in theta2 and slow gamma oscillations after salicylate injection in normal hearing young mice. This work further support the hypothesis that anxiety-like behavior after salicylate injection is triggered by tinnitus and require normal hearing. Moreover, our results show that hallucinogenic compounds can be effective in treating tinnitus-related anxiety.
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Affiliation(s)
- Jessica Winne
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil; Developmental Genetics Unit, Department of Neuroscience, Uppsala University, Husarg 3, Uppsala 75234, Sweden
| | - Barbara C Boerner
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil
| | - Thawann Malfatti
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil
| | - Elis Brisa
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil
| | - Jhulimar Doerl
- Neural Development and Environment Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal, RN, Brazil
| | - Ingrid Nogueira
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil
| | - Katarina E Leão
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil
| | - Richardson N Leão
- Neurodynamics Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal/RN, Brazil; Neural Development and Environment Lab, Brain Institute, Federal University of the Rio Grande do Norte, Av. Nascimento de Castro 2155, 59560-450 Natal, RN, Brazil.
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Salvi R, Auerbach BD, Lau C, Chen YC, Manohar S, Liu X, Ding D, Chen GD. Functional Neuroanatomy of Salicylate- and Noise-Induced Tinnitus and Hyperacusis. Curr Top Behav Neurosci 2020; 51:133-160. [PMID: 32653998 DOI: 10.1007/7854_2020_156] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tinnitus and hyperacusis are debilitating conditions often associated with aging or exposure to intense noise or ototoxic drugs. One of the most reliable methods of inducing tinnitus is with high doses of sodium salicylate, the active ingredient in aspirin. High doses of salicylate have been widely used to investigate the functional neuroanatomy of tinnitus and hyperacusis. High doses of salicylate have been used to develop novel behavioral methods to detect the presence of tinnitus and hyperacusis in animal models. Salicylate typically induces a hearing loss of approximately 20 dB which greatly reduces the neural output of the cochlea. As this weak neural signal emerging from the cochlea is sequentially relayed to the cochlear nucleus, inferior colliculus, medial geniculate, and auditory cortex, the neural response to suprathreshold sounds is progressively amplified by a factor of 2-3 by the time the signal reaches the auditory cortex, a phenomenon referred to as enhanced central gain. Sound-evoked hyperactivity also occurred in the amygdala, a region that assigns emotional significance to sensory stimuli. Resting state functional magnetic imaging of the BOLD signal revealed salicylate-induced increases in spontaneous neural activity in the inferior colliculus, medial geniculate body, and auditory cortex as well as in non-auditory areas such as the amygdala, reticular formation, cerebellum, and other sensory areas. Functional connectivity of the BOLD signal revealed increased neural coupling between several auditory areas and non-auditory areas such as the amygdala, cerebellum, reticular formation, hippocampus, and caudate/putamen; these strengthened connections likely contribute to the multifaceted dimensions of tinnitus. Taken together, these results suggest that salicylate-induced tinnitus disrupts a complex neural network involving many auditory centers as well as brain regions involved with emotion, arousal, memory, and motor planning. These extra-auditory centers embellish the basic auditory percepts that results in tinnitus and which may also contribute to hyperacusis.
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Affiliation(s)
- Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA.
| | | | - Condon Lau
- Department of Physics, City University of Hong Kong, Hong Kong, China
| | - Yu-Chen Chen
- Department of Radiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | | | - Xiaopeng Liu
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Dalian Ding
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Guang-Di Chen
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
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33
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Zhang W, Peng Z, Yu S, Song QL, Qu TF, Liu K, Gong SS. Exposure to sodium salicylate disrupts VGLUT3 expression in cochlear inner hair cells and contributes to tinnitus. Physiol Res 2019; 69:181-190. [PMID: 31852197 DOI: 10.33549/physiolres.934180] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
To examine whether exposure to sodium salicylate disrupts expression of vesicular glutamate transporter 3 (VGLUT3) and whether the alteration in expression corresponds to increased risk for tinnitus. Rats were treated with saline (control) or sodium salicylate (treated) Rats were examined for tinnitus by monitoring gap-pre-pulse inhibition of the acoustic startle reflex (GPIAS). Auditory brainstem response (ABR) was applied to evaluate hearing function after treatment. Rats were sacrificed after injection to obtain the cochlea, cochlear nucleus (CN), and inferior colliculus (IC) for examination of VGLUT3 expression. No significant differences in hearing thresholds between groups were identified (p>0.05). Tinnitus in sodium salicylate-treated rats was confirmed by GPIAS. VGLUT3 encoded by solute carrier family 17 members 8 (SLC17a8) expression was significantly increased in inner hair cells (IHCs) of the cochlea in treated animals, compared with controls (p<0.01). No significant differences in VGLUT3 expression between groups were found for the cochlear nucleus (CN) or IC (p>0.05). Exposure to sodium salicylate may disrupt SLC17a8 expression in IHCs, leading to alterations that correspond to tinnitus in rats. However, the CN and IC are unaffected by exposure to sodium salicylate, suggesting that enhancement of VGLUT3 expression in IHCs may contribute to the pathogenesis of tinnitus.
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Affiliation(s)
- W Zhang
- Department of Otolaryngology - Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China, Z. Peng or K. Liu or S.-S. Gong
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Duron J, Monconduit L, Avan P. Auditory Brainstem Changes in Timing may Underlie Hyperacusis in a Salicylate-induced Acute Rat Model. Neuroscience 2019; 426:129-140. [PMID: 31846750 DOI: 10.1016/j.neuroscience.2019.11.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 11/23/2019] [Accepted: 11/25/2019] [Indexed: 10/25/2022]
Abstract
Hyperacusis, an exaggerated, sometimes painful perception of loudness even for soft sounds, is a poorly understood distressing condition. While the involvement of modified gain of central auditory neurons and the influence of nonauditory brain regions are well-documented, the issue of where in the auditory system these abnormalities arise remains open, particularly when hyperacusis comes without sensorineural hearing loss. Here we used acute intraperitoneal administration of sodium salicylate (150 mg/kg) in rats, enough to produce > 10-dB decrease in acoustic startle threshold with mild hearing loss at low frequencies (<10 kHz). Anesthesia, necessary for middle-ear-reflex (MEMR) threshold measurements, abolished the olivocochlear efferent reflex but not the MEMR acting on frequencies < 10 kHz, and its mean threshold increased from 55 dB SPL in controls to 80 dB SPL in salicylate-treated animals 60-90 minutes after injection, with an about 3-dB increase in acoustic energy reaching the cochlea. The mean latencies of auditory brainstem-evoked responses (ABR) conspicuously decreased after salicylate, by 0.25 millisecond at 6 kHz at every level, a frequency-dependent effect absent above 12 kHz. A generic model of loudness based upon cross-frequency coincidence detection predicts that with such timing changes, a transient sound may seem as loud at <40 dB SPL as it does in controls at >60 dB SPL. Candidate circuits able to act at the same time on the startle reflex, the MEMR and ABRs may be serotoninergic, as salicylate is known to increase brain serotonin and 5-HT neurons participate in MEMR and ABR circuits.
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Affiliation(s)
- Julie Duron
- School of Medicine, University Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France; UMR INSERM 1107, School of Medicine, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France; Audioconsulting, Audition Conseil, 16 rue Blatin, 63000 Clermont-Ferrand, France.
| | - Lénaic Monconduit
- School of Dentistry, University Clermont Auvergne, 2 Rue de Braga, 63100 Clermont-Ferrand, France; UMR INSERM 1107, School of Medicine, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France.
| | - Paul Avan
- School of Medicine, University Clermont Auvergne, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France; UMR INSERM 1107, School of Medicine, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France; Centre Jean Perrin, 30 rue Montalembert, 63000 Clermont-Ferrand, France.
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Holt AG, Kühl A, Braun RD, Altschuler R. The rat as a model for studying noise injury and otoprotection. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:3681. [PMID: 31795688 DOI: 10.1121/1.5131344] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A major challenge for those studying noise-induced injury pre-clinically is the selection of an animal model. Noise injury models are particularly relevant in an age when people are constantly bombarded by loud noise due to occupation and/or recreation. The rat has been widely used for noise-related morphological, physiological, biochemical, and molecular assessment. Noise exposure resulting in a temporary (TTS) or permanent threshold shift (PTS) yields trauma in peripheral and central auditory related pathways. While the precise nature of noise-related injuries continues to be delineated, both PTS and TTS (with or without hidden hearing loss) result in homeostatic changes implicated in conditions such as tinnitus and hyperacusis. Compared to mice, rats generally tolerate exposure to loud sounds reasonably well, often without exhibiting other physical non-inner ear related symptoms such as death, loss of consciousness, or seizures [Skradski, Clark, Jiang, White, Fu, and Ptacek (2001). Neuron 31, 537-544; Faingold (2002). Hear. Res. 168, 223-237; Firstova, Abaimov, Surina, Poletaeva, Fedotova, and Kovalev (2012). Bull Exp. Biol. Med. 154, 196-198; De Sarro, Russo, Citraro, and Meldrum (2017). Epilepsy Behav. 71, 165-173]. This ability of the rat to thrive following noise exposure permits study of long-term effects. Like the mouse, the rat also offers a well-characterized genome allowing genetic manipulations (i.e., knock-out, viral-based gene expression modulation, and optogenetics). Rat models of noise-related injury also provide valuable information for understanding mechanistic changes to identify therapeutic targets for treatment. This article provides a framework for selection of the rat as a model for noise injury studies.
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Affiliation(s)
- Avril Genene Holt
- Department of Ophthalmology, Visual, and Anatomical Sciences (OVAS), School of Medicine, Wayne State University, 550 East Canfield Avenue, 454 Lande Building, Detroit, Michigan 48201, USA
| | - André Kühl
- Department of Ophthalmology, Visual, and Anatomical Sciences (OVAS), School of Medicine, Wayne State University, 550 East Canfield Avenue, 454 Lande Building, Detroit, Michigan 48201, USA
| | - Rod D Braun
- Department of Ophthalmology, Visual, and Anatomical Sciences (OVAS), School of Medicine, Wayne State University, 550 East Canfield Avenue, 454 Lande Building, Detroit, Michigan 48201, USA
| | - Richard Altschuler
- Department of Otolaryngology; Cell and Developmental Biology, Kresge Hearing Research Institute, University of Michigan, 1150 West Medical Center Drive, Ann Arbor, Michigan 48109, USA
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Sheppard A, Stocking C, Ralli M, Salvi R. A review of auditory gain, low-level noise and sound therapy for tinnitus and hyperacusis. Int J Audiol 2019; 59:5-15. [DOI: 10.1080/14992027.2019.1660812] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Adam Sheppard
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
| | - Christina Stocking
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
| | - Massimo Ralli
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Rome, Italy
| | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
- Department of Communicative Disorders and Sciences, University at Buffalo, Buffalo, NY, USA
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Farahani S, Nasirinezhad F, Danyali S, Jalaei S, Shahbazi A, Karimi M, Mokrian H. Does 5, 7-Dihydroxytryptamine injection into nucleus accumbens cause hyperacusis? Neurosci Lett 2019; 705:246-250. [DOI: 10.1016/j.neulet.2019.01.040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/13/2019] [Accepted: 01/22/2019] [Indexed: 11/30/2022]
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Auerbach BD, Radziwon K, Salvi R. Testing the Central Gain Model: Loudness Growth Correlates with Central Auditory Gain Enhancement in a Rodent Model of Hyperacusis. Neuroscience 2019; 407:93-107. [PMID: 30292765 PMCID: PMC8792806 DOI: 10.1016/j.neuroscience.2018.09.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/18/2018] [Accepted: 09/25/2018] [Indexed: 10/28/2022]
Abstract
The central gain model of hyperacusis proposes that loss of auditory input can result in maladaptive neuronal gain increases in the central auditory system, leading to the over-amplification of sound-evoked activity and excessive loudness perception. Despite the attractiveness of this model, and supporting evidence for it, a critical test of the central gain theory requires that changes in sound-evoked activity be explicitly linked to perceptual alterations of loudness. Here we combined an operant conditioning task that uses a subject's reaction time to auditory stimuli to produce reliable measures of loudness growth with chronic electrophysiological recordings from the auditory cortex and inferior colliculus of awake, behaviorally-phenotyped animals. In this manner, we could directly correlate daily assessments of loudness perception with neurophysiological measures of sound encoding within the same animal. We validated this novel psychophysical-electrophysiological paradigm with a salicylate-induced model of hearing loss and hyperacusis, as high doses of sodium salicylate reliably induce temporary hearing loss, neural hyperactivity, and auditory perceptual disruptions like tinnitus and hyperacusis. Salicylate induced parallel changes to loudness growth and evoked response-intensity functions consistent with temporary hearing loss and hyperacusis. Most importantly, we found that salicylate-mediated changes in loudness growth and sound-evoked activity were correlated within individual animals. These results provide strong support for the central gain model of hyperacusis and demonstrate the utility of using an experimental design that allows for within-subject comparison of behavioral and electrophysiological measures, thereby making inter-subject variability a strength rather than a limitation.
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Affiliation(s)
- Benjamin D Auerbach
- Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY 14214, USA.
| | - Kelly Radziwon
- Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY 14214, USA
| | - Richard Salvi
- Center for Hearing and Deafness, State University of New York at Buffalo, Buffalo, NY 14214, USA
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39
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Sedley W. Tinnitus: Does Gain Explain? Neuroscience 2019; 407:213-228. [DOI: 10.1016/j.neuroscience.2019.01.027] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/15/2019] [Accepted: 01/17/2019] [Indexed: 02/01/2023]
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Castañeda R, Natarajan S, Jeong SY, Hong BN, Kang TH. Electrophysiological changes in auditory evoked potentials in rats with salicylate-induced tinnitus. Brain Res 2019; 1715:235-244. [PMID: 30958992 DOI: 10.1016/j.brainres.2019.04.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/01/2019] [Accepted: 04/04/2019] [Indexed: 11/19/2022]
Abstract
Early-response auditory evoked potentials (AEPs) in humans are significantly altered in tinnitus. These changes are closely related to that seen in animals, leading to new approaches to study tinnitus based on objective parameters. The purpose of this study was to characterize the AEPs in animals with tinnitus, by assessing early to late latency responses. For behavioral evaluation, rats were trained using positive reinforcement to press a lever in the presence of an auditory stimulus and to not press during silence. The auditory brainstem response (ABR), middle latency response (MLR) and auditory late latency response (LLR) were correlated to the false-positive responses (pressing the lever during silence), after oral administrations of Sodium Salicylate (SS, 350 mg/kg). In the present study, SS significantly increased the hearing thresholds and reduced ABR peak I amplitudes across the frequency range (4-32 kHz). In contrast, increased amplitudes were observed for several peaks in ABR, MLR, and LLR. Moreover, reduced ABR latencies in response to 8, 16 and 24 kHz tone bursts were observed after SS administration. Similarly, the central evaluation also revealed significantly reduced latencies in MLR and LLR during SS administration. In contrast, increased latencies were observed for ABR latencies in response to 32 kHz tone bursts, and at the P1-N1 component of LLR. Correlational analysis revealed that latencies and amplitudes of peaks II and IV (8 and 16 kHz) of ABR, and N2 latency and P2-N2 amplitude of LLR were associated with behavioral tinnitus. We suggest that AEPs can be used in the rat to evaluate the reduced sensory input and the increased central gain in SS-induced tinnitus, as well as reduced latencies (8-16 kHz) to distinguish between hearing loss and tinnitus.
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Affiliation(s)
- Rodrigo Castañeda
- Graduate School of Biotechnology, Kyung Hee University, Republic of Korea; Department of Oriental Medicine Biotechnology, College of Life Sciences, Kyung Hee University, Global Campus, Gyeonggi, Republic of Korea; Department of Pharmacology and Physiology, School of Pharmacy, San Carlos University, Guatemala
| | - Sathishkumar Natarajan
- Graduate School of Biotechnology, Kyung Hee University, Republic of Korea; Department of Oriental Medicine Biotechnology, College of Life Sciences, Kyung Hee University, Global Campus, Gyeonggi, Republic of Korea
| | - Seo Yule Jeong
- Graduate School of Biotechnology, Kyung Hee University, Republic of Korea; Department of Oriental Medicine Biotechnology, College of Life Sciences, Kyung Hee University, Global Campus, Gyeonggi, Republic of Korea
| | - Bin Na Hong
- Graduate School of Biotechnology, Kyung Hee University, Republic of Korea
| | - Tong Ho Kang
- Graduate School of Biotechnology, Kyung Hee University, Republic of Korea; Department of Oriental Medicine Biotechnology, College of Life Sciences, Kyung Hee University, Global Campus, Gyeonggi, Republic of Korea.
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Qu T, Qi Y, Yu S, Du Z, Wei W, Cai A, Wang J, Nie B, Liu K, Gong S. Dynamic Changes of Functional Neuronal Activities Between the Auditory Pathway and Limbic Systems Contribute to Noise-Induced Tinnitus with a Normal Audiogram. Neuroscience 2019; 408:31-45. [PMID: 30946875 DOI: 10.1016/j.neuroscience.2019.03.054] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 12/20/2022]
Abstract
Tinnitus is thought to be triggered by aberrant neural activity in the central auditory pathway and is often accompanied by comorbidities of emotional distress and anxiety, which imply maladaptive functional connectivity to limbic structures, such as the amygdala and hippocampus. Tinnitus patients with normal audiograms can also have accompanying anxiety and depression, clinically. To test the role of functional connectivity between the central auditory pathway and limbic structures in patients with tinnitus with normal audiograms, we developed a murine noise-induced tinnitus model with a temporary threshold shift (TTS). Tinnitus mice exhibited reduced auditory brainstem response wave I amplitude, and an enhanced wave IV amplitude and wave IV/I amplitude ratio, as compared with control and non-tinnitus mice. Resting-state functional magnetic resonance imaging (fMRI) was used to identify abnormal connectivity of the amygdala and hippocampus and to determine the relationship with tinnitus characteristics. We found increased fMRI responses with amplitude of low-frequency fluctuation (ALFF) in the auditory cortex and decreased ALFF in the amygdala and hippocampus at day 1, but decreased ALFF in the auditory cortex and increased ALFF in the amygdala at day 28 post-noise exposure in tinnitus mice. Decreased functional connectivity between auditory brain regions and limbic structures was demonstrated at day 28 in tinnitus mice. Therefore, aberrant neural activities in tinnitus mice with TTS involved not only the central auditory pathway, but also limbic structures, and there was maladaptive functional connectivity between the central auditory pathway and limbic structures, such as the amygdala and hippocampus.
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Affiliation(s)
- Tengfei Qu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Yue Qi
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Shukui Yu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Zhengde Du
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Wei Wei
- Department of Otology, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Aoling Cai
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Jie Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China; Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, PR China
| | - Binbin Nie
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ke Liu
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China.
| | - Shusheng Gong
- Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China.
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Wood NJ, Lowe AS, Walton JP. Sodium salicylate alters temporal integration measured through increasing stimulus presentation rates. Int J Audiol 2019; 58:141-150. [PMID: 30845859 DOI: 10.1080/14992027.2018.1544424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE High doses of sodium salicylate (SS) are known to induce tinnitus, general hyperexcitability in the central auditory system, and to cause mild hearing loss. We used the auditory brainstem response (ABR) to assess the effects of SS on auditory sensitivity and temporal processing in the auditory nerve and brainstem. ABRs were evoked using tone burst stimuli varying in frequency and intensity with presentation rates from 11/s to 81/s. DESIGN ABRs were recorded and analysed prior to and after SS treatment in each animal, and peak 1 and peak 4 amplitudes and latencies were determined along with minimal response threshold. STUDY SAMPLE Nine young adult CBA/CaJ mice were used in a longitudinal within-subject design. RESULTS No measurable effects of presentation rate were found on ABR threshold prior to SS; however, following SS administration increasing stimulus rates lowered ABR thresholds by as much as 10 dB and compressed the peak amplitude by intensity level functions. CONCLUSIONS These results suggest that SS alters temporal integration and compressive nonlinearity, and that varying the stimulus rate of the ABR may prove to be a useful diagnostic tool in the study of hearing disorders that involve hyperexcitability.
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Affiliation(s)
- Nicole J Wood
- a Department of Biology , University of South Florida , Tampa , FL , USA.,b Morsani College of Medicine , University of South Florida , Tampa , FL , USA.,c Global Center for Hearing and Speech Research , University of South Florida , Tampa , FL , USA
| | - Andrea S Lowe
- c Global Center for Hearing and Speech Research , University of South Florida , Tampa , FL , USA.,d Department of Chemical and Biomedical Engineering , University of South Florida , Tampa , FL , USA
| | - Joseph P Walton
- c Global Center for Hearing and Speech Research , University of South Florida , Tampa , FL , USA.,d Department of Chemical and Biomedical Engineering , University of South Florida , Tampa , FL , USA.,e Department of Communication Sciences and Disorders , University of South Florida , Tampa , FL , USA
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Pienkowski M. Prolonged Exposure of CBA/Ca Mice to Moderately Loud Noise Can Cause Cochlear Synaptopathy but Not Tinnitus or Hyperacusis as Assessed With the Acoustic Startle Reflex. Trends Hear 2019. [PMID: 29532738 PMCID: PMC5858683 DOI: 10.1177/2331216518758109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Hearing loss changes the auditory brain, sometimes maladaptively. When deprived of cochlear input, central auditory neurons become more active spontaneously and begin to respond more strongly and synchronously to better preserved sound frequencies. This spontaneous and sound-evoked central hyperactivity has been postulated to trigger tinnitus and hyperacusis, respectively. Localized hyperactivity has also been observed after long-term exposure to noise levels that do not damage the cochlea. Adult animals exposed to bands of nondamaging noise exhibited suppressed spontaneous and sound-evoked activity in the area of primary auditory cortex (A1) stimulated by the exposure band but had increased spontaneous and evoked activity in neighboring A1 areas. We hypothesized that the cortically suppressed frequencies should for some time after exposure be perceived as less loud than before (hypoacusis), whereas the hyperactivity outside of the exposure band might lead to frequency-specific hyperacusis or tinnitus. To investigate this, adult CBA/Ca mice were exposed for >2 months to 8 to 16 kHz noise at 70 or 75 dB sound pressure level and tested for hypo-/hyperacusis and tinnitus using tone and gap prepulse inhibition of the acoustic startle reflex. Auditory brainstem responses and distortion product otoacoustic emissions showed evidence of cochlear synaptopathy after exposure at 75 but not 70 dB, putting a lower bound on damaging noise levels for CBA/Ca mice. Contrary to hypothesis, neither exposure significantly shifted startle results from baseline. These negative findings nevertheless have implications for startle test methodology and for the putative role of central hyperactivity in hyperacusis and tinnitus.
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Affiliation(s)
- Martin Pienkowski
- 1 Osborne College of Audiology, Salus University, Elkins Park, PA, USA
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Vianney-Rodrigues P, Auerbach BD, Salvi R. Aberrant thalamocortical coherence in an animal model of tinnitus. J Neurophysiol 2019; 121:893-907. [PMID: 30625004 PMCID: PMC6520628 DOI: 10.1152/jn.00053.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 12/14/2018] [Accepted: 01/07/2019] [Indexed: 11/22/2022] Open
Abstract
Electrophysiological and imaging studies from humans suggest that the phantom sound of tinnitus is associated with abnormal thalamocortical neural oscillations (dysrhythmia) and enhanced gamma band activity in the auditory cortex. However, these models have seldom been tested in animal models where it is possible to simultaneously assess the neural oscillatory activity within and between the thalamus and auditory cortex. To explore this issue, we used multichannel electrodes to examine the oscillatory behavior of local field potentials recorded in the rat medial geniculate body (MBG) and primary auditory cortex (A1) before and after administering a dose of sodium salicylate (SS) that reliably induces tinnitus. In the MGB, SS reduced theta, alpha, and beta oscillations and decreased coherence (synchrony) between electrode pairs in theta, alpha, and beta bands but increased coherence in the gamma band. Within A1, SS significantly increased gamma oscillations, decreased theta power, and decreased coherence between electrode pairs in theta and alpha bands but increased coherence in the gamma band. When coherence was measured between one electrode in the MGB and another in A1, SS decreased coherence in beta, alpha, and theta bands but increased coherence in the gamma band. SS also increased cross-frequency coupling between the phase of theta oscillations in the MGB and amplitude of gamma oscillations in A1. Altogether, our results suggest that SS treatment fundamentally alters the manner in which thalamocortical circuits communicate, leading to excessive cortical gamma power and synchronization, neurophysiological changes implicated in tinnitus. Our data provide support for elements of both the thalamocortical dysrhythmia (TD) and synchronization by loss of inhibition (SLIM) models of tinnitus, demonstrating that increased cortical gamma band activity is associated with both enhanced theta-gamma coupling as well as decreases alpha power/coherence between the MGB and A1. NEW & NOTEWORTHY There are no effective drugs to alleviate the phantom sound of tinnitus because the physiological mechanisms leading to its generation are poorly understood. Neural models of tinnitus suggest that it arises from abnormal thalamocortical oscillations, but these models have not been extensively tested. This article identifies abnormal thalamocortical oscillations in a drug-induced tinnitus model. Our findings open up new avenues of research to investigate whether cellular mechanisms underlying thalamocortical oscillations are causally linked to tinnitus.
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Affiliation(s)
| | | | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo , Buffalo, New York
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Möhrle D, Hofmeier B, Amend M, Wolpert S, Ni K, Bing D, Klose U, Pichler B, Knipper M, Rüttiger L. Enhanced Central Neural Gain Compensates Acoustic Trauma-induced Cochlear Impairment, but Unlikely Correlates with Tinnitus and Hyperacusis. Neuroscience 2018; 407:146-169. [PMID: 30599268 DOI: 10.1016/j.neuroscience.2018.12.038] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 12/18/2018] [Accepted: 12/20/2018] [Indexed: 01/09/2023]
Abstract
For successful future therapeutic strategies for tinnitus and hyperacusis, a subcategorization of both conditions on the basis of differentiated neural correlates would be of invaluable advantage. In the present study, we used our refined operant conditioning animal model to divide equally noise-exposed rats into groups with either tinnitus or hyperacusis, with neither condition, or with both conditions co-occurring simultaneously. Using click stimulus and noise burst-evoked Auditory Brainstem Responses (ABR) and Distortion Product Otoacoustic Emissions, no hearing threshold difference was observed between any of the groups. However, animals with neither tinnitus nor hyperacusis responded to noise trauma with shortened ABR wave I and IV latencies and elevated central neuronal gain (increased ABR wave IV/I amplitude ratio), which was previously assumed in most of the literature to be a neural correlate for tinnitus. In contrast, animals with tinnitus had reduced neural response gain and delayed ABR wave I and IV latencies, while animals with hyperacusis showed none of these changes. Preliminary studies, aimed at establishing comparable non-invasive objective tools for identifying tinnitus in humans and animals, confirmed reduced central gain and delayed response latency in human and animals. Moreover, the first ever resting state functional Magnetic Resonance Imaging (rs-fMRI) analyses comparing humans and rats with and without tinnitus showed reduced rs-fMRI activities in the auditory cortex in both patients and animals with tinnitus. These findings encourage further efforts to establish non-invasive diagnostic tools that can be used in humans and animals alike and give hope for differentiated classification of tinnitus and hyperacusis.
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Affiliation(s)
- Dorit Möhrle
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Benedikt Hofmeier
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Mario Amend
- University of Tübingen, Department of Preclinical Imaging and Radiopharmacy, University Hospital Tübingen, Röntgenweg 13, 72076 Tübingen, Germany.
| | - Stephan Wolpert
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Kun Ni
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany; Shanghai Jiao Tong University, Department of Otolaryngology, Head & Neck Surgery, Shanghai Children's Hospital, Shanghai Luding Road, NO. 355. Putuo District, 200062 Shanghai, China.
| | - Dan Bing
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Uwe Klose
- University Hospital Tübingen, Department of Diagnostic and Interventional Neuroradiology, Hoppe-Seyler-Str. 3, 72076 Tübingen, Germany.
| | - Bernd Pichler
- University of Tübingen, Department of Preclinical Imaging and Radiopharmacy, University Hospital Tübingen, Röntgenweg 13, 72076 Tübingen, Germany.
| | - Marlies Knipper
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
| | - Lukas Rüttiger
- University of Tübingen, Department of Otolaryngology, Head & Neck Surgery, Tübingen Hearing Research Centre (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
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Wu C, Wu X, Yi B, Cui M, Wang X, Wang Q, Wu H, Huang Z. Changes in GABA and glutamate receptors on auditory cortical excitatory neurons in a rat model of salicylate-induced tinnitus. Am J Transl Res 2018; 10:3941-3955. [PMID: 30662641 PMCID: PMC6325520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/18/2018] [Indexed: 06/09/2023]
Abstract
Tinnitus is associated with neural hyperactivity, which is regulated by neuronal plasticity in the auditory central system, especially the auditory cortex (AC). Excitatory neurons constitute approximately 70-85% of the total populations of neuronal cells. However, few reports have focused on the AMPA receptor (AMPAR) and the GABAA receptor (GABAAR) on the excitatory neuron in animal model of tinnitus. In this study, we gave rats a single or long-term of salicylate administrations. The tinnitus-like behavior was assessed by combination of the gap prepulse inhibition of acoustic startle (GPIAS) and the pre-pulse inhibition (PPI) tests. Using immunofluorescent staining, we examined whether the AMPAR and the GABAAR on the calcium/calmodulin-dependent protein kinase IIα (CaMKIIα) -labeled excitatory neurons in the auditory cortex underwent changes following salicylate treatment. The rats with 14 days of salicylate administration showed evidence of experiencing tinnitus, while the rats receiving a single dose of salicylate manifested no tinnitus-like behavior. Furthermore, the AMPAR and GABAAR responded in a homeostatic manner after a single dose of salicylate while those showing in a Hebbian way after long-term salicylate administration. Thus, the different patterns of plasticity change in cortical excitatory neurons might affect the generating of salicylate-induced tinnitus.
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Affiliation(s)
- Cong Wu
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Xu Wu
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Bin Yi
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Mengchen Cui
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Xueling Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Qixuan Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Hao Wu
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
| | - Zhiwu Huang
- Department of Otorhinolaryngology Head and Neck Surgery, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Laboratory of Auditory Neuroscience, Ear Institute, School of Medicine, Shanghai Jiao Tong UniversityShanghai, China
- Shanghai Key Laboratory of Translational Medicine on Ear and Nose DiseasesShanghai, China
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Bhandiwad AA, Raible DW, Rubel EW, Sisneros JA. Noise-Induced Hypersensitization of the Acoustic Startle Response in Larval Zebrafish. J Assoc Res Otolaryngol 2018; 19:741-752. [PMID: 30191425 PMCID: PMC6249159 DOI: 10.1007/s10162-018-00685-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 01/21/2018] [Indexed: 01/28/2023] Open
Abstract
Overexposure to loud noise is known to lead to deficits in auditory sensitivity and perception. We studied the effects of noise exposure on sensorimotor behaviors of larval (5-7 days post-fertilization) zebrafish (Danio rerio), particularly the auditory-evoked startle response and hearing sensitivity to acoustic startle stimuli. We observed a temporary 10-15 dB decrease in startle response threshold after 18 h of flat-spectrum noise exposure at 20 dB re·1 ms-2. Larval zebrafish also exhibited decreased habituation to startle-inducing stimuli following noise exposure. The noise-induced sensitization was not due to changes in absolute hearing thresholds, but was specific to the auditory-evoked escape responses. The observed noise-induced sensitization was disrupted by AMPA receptor blockade using DNQX, but not NMDA receptor blockade. Together, these experiments suggest a complex effect of noise exposure on the neural circuits mediating auditory-evoked behaviors in larval zebrafish.
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Affiliation(s)
| | - David W. Raible
- Department of Biological Structure, University of Washington, Seattle, WA 98195 USA
- Department of Biology, University of Washington, Seattle, WA 98195 USA
- Virginia M. Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195 USA
| | - Edwin W. Rubel
- Department of Psychology, University of Washington, Seattle, WA 98195 USA
- Virginia M. Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195 USA
| | - Joseph A. Sisneros
- Department of Psychology, University of Washington, Seattle, WA 98195 USA
- Department of Biology, University of Washington, Seattle, WA 98195 USA
- Virginia M. Bloedel Hearing Research Center, University of Washington, Seattle, WA 98195 USA
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48
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Intermittent Low-level Noise Causes Negative Neural Gain in the Inferior Colliculus. Neuroscience 2018; 407:135-145. [PMID: 30458217 DOI: 10.1016/j.neuroscience.2018.11.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 11/06/2018] [Accepted: 11/08/2018] [Indexed: 01/07/2023]
Abstract
The central auditory system shows a remarkable ability to rescale its neural representation of loudness following long-term, low-level acoustic exposures; even when the noise is presented intermittently. Circadian rhythms exert potent biological effects, but it remains unclear if acoustic exposures occurring during the light or dark cycle affect the neurophysiological changes involved in loudness rescaling. To address this issue we exposed rats to intermittent (12 h/day), low-level noise (10-20 kHz, 75 dB SPL) for 5 weeks; exposures occurred during either the light (inactive) or dark (active) phase of the circadian cycle. The 12-h exposures, whether occurring during the light or dark phase, did not significantly alter cochlear function as reflected in distortion product otoacoustic emissions and compound action potential responses. However, neural activity in the inferior colliculus demonstrated negative gain in a frequency- and intensity-specific manner compared to unexposed controls; the magnitude and direction of the neuroplastic changes in the inferior colliculus were largely the same regardless of whether the 12-h noise exposures occurred during the light or dark phase of the circadian cycle. These neuroplastic changes could become relevant for low-level sound therapies used to treat hyperacusis.
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49
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Walton JP, Dziorny AC, Vasilyeva ON, Luebke AE. Loss of the Cochlear Amplifier Prestin Reduces Temporal Processing Efficacy in the Central Auditory System. Front Cell Neurosci 2018; 12:291. [PMID: 30297983 PMCID: PMC6160587 DOI: 10.3389/fncel.2018.00291] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 08/14/2018] [Indexed: 11/24/2022] Open
Abstract
Active mechanical amplification of sound occurs in cochlear outer hair cells (OHCs) that change their length with oscillations of their membrane potential. Such length changes are the proposed cellular source of the cochlear amplifier, and prestin is the motor protein responsible for OHC electromotility. Previous findings have shown that mice lacking prestin displayed a loss of OHC electromotility, subsequent loss of distortion-product otoacoustic emissions, and a 40–60 dB increase in hearing thresholds. In this study we were interested in studying the functional consequences of the complete loss of cochlear amplification on neural coding of frequency selectivity, tuning, and temporal processing in the auditory midbrain. We recorded near-field auditory evoked potentials and multi-unit activity from the inferior colliculus (IC) of prestin (−/−) null and prestin (+/+) wild-type control mice and determined frequency response areas (FRAs), tuning sharpness, and gap detection to tone bursts and silent gaps embedded in broadband noise. We were interested in determining if the moderate to severe sensorineural hearing loss associated with the loss of motor protein prestin would also impair auditory midbrain temporal-processing measures, or if compensatory mechanisms within the brainstem could compensate for the loss of prestin. In prestin knockout mice we observed that there are severe impairments in midbrain tuning, thresholds, excitatory drive, and gap detection suggesting that brainstem and midbrain processing could not overcome the auditory processing deficits afforded by the loss of OHC electromotility mediated by the prestin protein.
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Affiliation(s)
- Joseph P Walton
- Department of Communication Sciences and Disorders, University of South Florida, Tampa, FL, United States.,Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States.,Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL, United States
| | - Adam C Dziorny
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States
| | - Olga N Vasilyeva
- Department of Neuroscience, The Ernest J. Del Monte Institute for Neuroscience, University of Rochester Medical Center, Rochester, NY, United States
| | - Anne E Luebke
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, United States.,Department of Neuroscience, The Ernest J. Del Monte Institute for Neuroscience, University of Rochester Medical Center, Rochester, NY, United States
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Muca A, Standafer E, Apawu AK, Ahmad F, Ghoddoussi F, Hali M, Warila J, Berkowitz BA, Holt AG. Tinnitus and temporary hearing loss result in differential noise-induced spatial reorganization of brain activity. Brain Struct Funct 2018; 223:2343-2360. [PMID: 29488007 PMCID: PMC6129978 DOI: 10.1007/s00429-018-1635-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 02/17/2018] [Indexed: 12/27/2022]
Abstract
Loud noise frequently results in hyperacusis or hearing loss (i.e., increased or decreased sensitivity to sound). These conditions are often accompanied by tinnitus (ringing in the ears) and changes in spontaneous neuronal activity (SNA). The ability to differentiate the contributions of hyperacusis and hearing loss to neural correlates of tinnitus has yet to be achieved. Towards this purpose, we used a combination of behavior, electrophysiology, and imaging tools to investigate two models of noise-induced tinnitus (either with temporary hearing loss or with permanent hearing loss). Manganese (Mn2+) uptake was used as a measure of calcium channel function and as an index of SNA. Manganese uptake was examined in vivo with manganese-enhanced magnetic resonance imaging (MEMRI) in key auditory brain regions implicated in tinnitus. Following acoustic trauma, MEMRI, the SNA index, showed evidence of spatially dependent rearrangement of Mn2+ uptake within specific brain nuclei (i.e., reorganization). Reorganization of Mn2+ uptake in the superior olivary complex and cochlear nucleus was dependent upon tinnitus status. However, reorganization of Mn2+ uptake in the inferior colliculus was dependent upon hearing sensitivity. Furthermore, following permanent hearing loss, reduced Mn2+ uptake was observed. Overall, by combining testing for hearing sensitivity, tinnitus, and SNA, our data move forward the possibility of discriminating the contributions of hyperacusis and hearing loss to tinnitus.
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Affiliation(s)
- Antonela Muca
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - Emily Standafer
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - Aaron K Apawu
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - Farhan Ahmad
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - Farhad Ghoddoussi
- Department of Anesthesiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Mirabela Hali
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - James Warila
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
| | - Bruce A Berkowitz
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA
- Department of Ophthalmology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Avril Genene Holt
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 550 East Canfield Ave., Detroit, MI, 48201, USA.
- John D. Dingell VAMC, Detroit, MI, USA.
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