1
|
Farmer AL, Lewis MH. Reduction of restricted repetitive behavior by environmental enrichment: Potential neurobiological mechanisms. Neurosci Biobehav Rev 2023; 152:105291. [PMID: 37353046 DOI: 10.1016/j.neubiorev.2023.105291] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/04/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023]
Abstract
Restricted repetitive behaviors (RRB) are one of two diagnostic criteria for autism spectrum disorder and common in other neurodevelopmental and psychiatric disorders. The term restricted repetitive behavior refers to a wide variety of inflexible patterns of behavior including stereotypy, self-injury, restricted interests, insistence on sameness, and ritualistic and compulsive behavior. However, despite their prevalence in clinical populations, their underlying causes remain poorly understood hampering the development of effective treatments. Intriguingly, numerous animal studies have demonstrated that these behaviors are reduced by rearing in enriched environments (EE). Understanding the processes responsible for the attenuation of repetitive behaviors by EE should offer insights into potential therapeutic approaches, as well as shed light on the underlying neurobiology of repetitive behaviors. This review summarizes the current knowledge of the relationship between EE and RRB and discusses potential mechanisms for EE's attenuation of RRB based on the broader EE literature. Existing gaps in the literature and future directions are also discussed.
Collapse
Affiliation(s)
- Anna L Farmer
- Department of Psychology, University of Florida, Gainesville, FL, USA.
| | - Mark H Lewis
- Department of Psychology, University of Florida, Gainesville, FL, USA; Department of Psychiatry, University of Florida, Gainesville, FL, USA
| |
Collapse
|
2
|
Koiek S, Brandt C, Schmidt JH, Neher T. Monaural and binaural phase sensitivity in school-age children with early-childhood otitis media. Int J Audiol 2021; 61:1054-1061. [PMID: 34883026 DOI: 10.1080/14992027.2021.2009132] [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: 10/19/2022]
Abstract
OBJECTIVE Previous research has linked recurrent otitis media (OM) during early childhood to reduced binaural masking level differences (BMLDs) in school-age children. How this finding relates to monaural processing abilities and the individual otologic history has not been investigated systematically. The current study, therefore, addressed these issues. DESIGN Sensitivity to monaural and binaural phase information was assessed using a common test paradigm. To evaluate the influence of the otologic history, overall OM duration, OM onset age, and the time since the last OM episode were considered in the analyses. STUDY SAMPLE Children aged 6-13 years with a history of recurrent OM (N = 42) or without any previous ear diseases (N = 20). RESULTS Compared to the controls, the OM children showed smaller BMLDs (p < 0.05) whereas their monaural and binaural detection thresholds were comparable (p > 0.05). After controlling for age, the otologic history factors failed to predict the BMLDs of the OM children. Their monaural detection thresholds were correlated with the binaural detection thresholds (r = ∼0.5, p < 0.05) but not the BMLDs. CONCLUSIONS The current study suggests that early-childhood OM can impair binaural processing abilities in school-age children.
Collapse
Affiliation(s)
- Shno Koiek
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.,Research Unit for ORL-Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Christian Brandt
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.,Research Unit for ORL-Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Jesper Hvass Schmidt
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.,Research Unit for ORL-Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark.,Department of Otolaryngology, Head & Neck Surgery and Audiology, Odense University Hospital, Odense, Denmark
| | - Tobias Neher
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.,Research Unit for ORL-Head & Neck Surgery and Audiology, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| |
Collapse
|
3
|
Environmental enrichment ameliorates high-fat diet induced olfactory deficit and decrease of parvalbumin neurons in the olfactory bulb in mice. Brain Res Bull 2021; 179:13-24. [PMID: 34848271 DOI: 10.1016/j.brainresbull.2021.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 11/14/2021] [Accepted: 11/24/2021] [Indexed: 11/23/2022]
Abstract
Overweight induced by high-fat diet (HFD) represents one of the major health concerns in modern societies, which can cause lasting peripheral and central metabolic disorders in all age groups. Specifically, childhood obesity could lead to life-long impact on brain development and functioning. On the other hand, environmental enrichment (EE) has been demonstrated to be beneficial for learning and memory. Here, we explored the impact of high-fat diet on olfaction and organization of olfactory bulb cells in adolescent mice, and the effect of EE intervention thereon. Puberty mice (3-week-old) fed with HFD for 10 weeks exhibited poorer odor sensitivity and olfactory memory relative to controls consuming standard chows. The behavioral deficits were rescued in the HFD group with EE intervention. Neuroanatomically, parvalbumin (PV) interneurons in the olfactory bulb (OB) were reduced in the HFD-fed animals relative to control, while EE intervention also normalized this alteration. In contrast, cells expressing calbindin (CB), doublecortin (DCX) in the OB were not altered. Our findings suggest that PV interneurons may play a crucial role in mediating the HFD-induced olfactory deficit in adolescent mice, and can also serve a protective effect of EE against the functional deficit.
Collapse
|
4
|
Rescuing Auditory Temporal Processing with a Novel Augmented Acoustic Environment in an Animal Model of Congenital Hearing Loss. eNeuro 2021; 8:ENEURO.0231-21.2021. [PMID: 34155086 PMCID: PMC8281262 DOI: 10.1523/eneuro.0231-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/02/2021] [Indexed: 11/29/2022] Open
Abstract
Congenital sensorineural hearing loss (SNHL) affects thousands of infants each year and results in significant delays in speech and language development. Previous studies have shown that early exposure to a simple augmented acoustic environment (AAE) can limit the effects of progressive SNHL on hearing sensitivity. However, SNHL is also accompanied by hearing loss that is not assessed on standard audiological examinations, such as reduced temporal processing acuity. To assess whether sound therapy may improve these deficits, a mouse model of congenital SNHL was exposed to simple or temporally complex AAE. The DBA/2J mouse strain develops rapid, base to apex, progressive SNHL beginning at birth and is functionally deaf by six months of age. Hearing sensitivity and auditory brainstem function was measured using otoacoustic emissions, auditory brainstem response (ABR) and extracellular recording from the inferior colliculus (IC) in mice following exposure to 30 d of continuous AAE. Peripheral function and sound sensitivity in auditory midbrain neurons improved following exposure to both types of AAE. However, exposure to a novel, temporally complex AAE more strongly improved a measure of temporal processing acuity, neural gap-in-noise detection in the auditory midbrain. These experiments suggest that targeted sound therapy may be harnessed to improve hearing outcomes for children suffering from congenital SNHL.
Collapse
|
5
|
Svobodová Burianová J, Syka J. Postnatal exposure to an acoustically enriched environment alters the morphology of neurons in the adult rat auditory system. Brain Struct Funct 2020; 225:1979-1995. [PMID: 32588120 DOI: 10.1007/s00429-020-02104-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 06/16/2020] [Indexed: 11/29/2022]
Abstract
The structure of neurons in the central auditory system is vulnerable to various kinds of acoustic exposures during the critical postnatal developmental period. Here we explored long-term effects of exposure to an acoustically enriched environment (AEE) during the third and fourth weeks of the postnatal period in rat pups. AEE consisted of a spectrally and temporally modulated sound of moderate intensity, reinforced by a behavioral paradigm. At the age of 3-6 months, a Golgi-Cox staining was used to evaluate the morphology of neurons in the inferior colliculus (IC), the medial geniculate body (MGB), and the auditory cortex (AC). Compared to controls, rats exposed to AEE showed an increased mean dendritic length and volume and the soma surface in the external cortex and the central nucleus of the IC. The spine density increased in both the ventral and dorsal divisions of the MGB. In the AC, the total length and volume of the basal dendritic segments of pyramidal neurons and the number and density of spines on these dendrites increased significantly. No differences were found on apical dendrites. We also found an elevated number of spines and spine density in non-pyramidal neurons. These results show that exposure to AEE during the critical developmental period can induce permanent changes in the structure of neurons in the central auditory system. These changes represent morphological correlates of the functional plasticity, such as an improvement in frequency tuning and synchronization with temporal parameters of acoustical stimuli.
Collapse
Affiliation(s)
- Jana Svobodová Burianová
- Department of Auditory Neuroscience, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic.
| | - Josef Syka
- Department of Auditory Neuroscience, Institute of Experimental Medicine of the Czech Academy of Sciences, Prague, Czech Republic
| |
Collapse
|
6
|
Persic D, Thomas ME, Pelekanos V, Ryugo DK, Takesian AE, Krumbholz K, Pyott SJ. Regulation of auditory plasticity during critical periods and following hearing loss. Hear Res 2020; 397:107976. [PMID: 32591097 PMCID: PMC8546402 DOI: 10.1016/j.heares.2020.107976] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/15/2020] [Accepted: 04/14/2020] [Indexed: 02/07/2023]
Abstract
Sensory input has profound effects on neuronal organization and sensory maps in the brain. The mechanisms regulating plasticity of the auditory pathway have been revealed by examining the consequences of altered auditory input during both developmental critical periods—when plasticity facilitates the optimization of neural circuits in concert with the external environment—and in adulthood—when hearing loss is linked to the generation of tinnitus. In this review, we summarize research identifying the molecular, cellular, and circuit-level mechanisms regulating neuronal organization and tonotopic map plasticity during developmental critical periods and in adulthood. These mechanisms are shared in both the juvenile and adult brain and along the length of the auditory pathway, where they serve to regulate disinhibitory networks, synaptic structure and function, as well as structural barriers to plasticity. Regulation of plasticity also involves both neuromodulatory circuits, which link plasticity with learning and attention, as well as ascending and descending auditory circuits, which link the auditory cortex and lower structures. Further work identifying the interplay of molecular and cellular mechanisms associating hearing loss-induced plasticity with tinnitus will continue to advance our understanding of this disorder and lead to new approaches to its treatment. During CPs, brain plasticity is enhanced and sensitive to acoustic experience. Enhanced plasticity can be reinstated in the adult brain following hearing loss. Molecular, cellular, and circuit-level mechanisms regulate CP and adult plasticity. Plasticity resulting from hearing loss may contribute to the emergence of tinnitus. Modifying plasticity in the adult brain may offer new treatments for tinnitus.
Collapse
Affiliation(s)
- Dora Persic
- University of Groningen, University Medical Center Groningen, Groningen, Department of Otorhinolaryngology and Head/Neck Surgery, 9713, GZ, Groningen, the Netherlands
| | - Maryse E Thomas
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear and Department of Otorhinolaryngology and Head/Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - Vassilis Pelekanos
- Hearing Sciences, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, University Park, Nottingham, UK
| | - David K Ryugo
- Hearing Research, Garvan Institute of Medical Research, Sydney, NSW, 2010, Australia; School of Medical Sciences, UNSW Sydney, Sydney, NSW, 2052, Australia; Department of Otolaryngology, Head, Neck & Skull Base Surgery, St Vincent's Hospital, Sydney, NSW, 2010, Australia
| | - Anne E Takesian
- Eaton-Peabody Laboratories, Massachusetts Eye & Ear and Department of Otorhinolaryngology and Head/Neck Surgery, Harvard Medical School, Boston, MA, USA
| | - Katrin Krumbholz
- Hearing Sciences, Division of Clinical Neuroscience, School of Medicine, University of Nottingham, University Park, Nottingham, UK
| | - Sonja J Pyott
- University of Groningen, University Medical Center Groningen, Groningen, Department of Otorhinolaryngology and Head/Neck Surgery, 9713, GZ, Groningen, the Netherlands.
| |
Collapse
|
7
|
Zhou M, Yuan J, Yan Z, Dai J, Wang X, Xu T, Xu Z, Wang N, Liu J. Intrinsic and Miniature Postsynaptic Current Changes in Rat Principal Neurons of the Lateral Superior Olive after Unilateral Auditory Deprivation at an Early Age. Neuroscience 2019; 428:2-12. [PMID: 31866557 DOI: 10.1016/j.neuroscience.2019.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 11/30/2019] [Accepted: 12/02/2019] [Indexed: 01/13/2023]
Abstract
Unilateral auditory deprivation results in lateralization changes in the central auditory system, interfering with the integration of binaural information and thereby leading to a decrease in binaural auditory functions such as sound localization. Principal neurons of the lateral superior olive (LSO) are responsible for computing the interaural intensity differences that are critical for sound localization in the horizontal plane. To investigate changes caused by unilateral auditory deprivation, electrophysiological activity was recorded from LSO principal neurons in control rats and rats with unilateral cochlear ablation. At one week after unilateral cochlear ablation, the excitability of LSO principal neurons on the side ipsilateral to the ablation (the ablated side) was greater than that on the side contralateral to the ablation (the intact side); however, the input resistance increased on both sides. Furthermore, by analysing the miniature inhibitory postsynaptic currents and miniature excitatory postsynaptic currents, we found that unilateral auditory deprivation weakened the inhibitory driving force on the intact side, whereas it strengthened the excitatory driving force on the ablated side. In summary, asymmetric changes in the electrophysiological activity of LSO principal neurons were found on both sides at postnatal day 19, one week after unilateral cochlear ablation.
Collapse
Affiliation(s)
- Mo Zhou
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Jingjing Yuan
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Zhanfeng Yan
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Jinsheng Dai
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Xing Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China
| | - Tao Xu
- Department of Neurobiology, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Laboratory of Brain Disorders (Ministry of Science and Technology), Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Zhiqing Xu
- Department of Neurobiology, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Laboratory of Brain Disorders (Ministry of Science and Technology), Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Ningyu Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Jinfeng Liu
- Department of Otorhinolaryngology Head and Neck Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| |
Collapse
|
8
|
Liu X, Wei F, Cheng Y, Zhang Y, Jia G, Zhou J, Zhu M, Shan Y, Sun X, Yu L, Merzenich MM, Lurie DI, Zheng Q, Zhou X. Auditory Training Reverses Lead (Pb)-Toxicity-Induced Changes in Sound-Azimuth Selectivity of Cortical Neurons. Cereb Cortex 2019; 29:3294-3304. [PMID: 30137254 DOI: 10.1093/cercor/bhy199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 07/20/2018] [Accepted: 07/26/2018] [Indexed: 01/16/2023] Open
Abstract
Lead (Pb) causes significant adverse effects on the developing brain, resulting in cognitive and learning disabilities in children. The process by which lead produces these negative changes is largely unknown. The fact that children with these syndromes also show deficits in central auditory processing, however, indicates a speculative but disturbing relationship between lead-exposure, impaired auditory processing, and behavioral dysfunction. Here we studied in rats the changes in cortical spatial tuning impacted by early lead-exposure and their potential restoration to normal by auditory training. We found animals that were exposed to lead early in life displayed significant behavioral impairments compared with naïve controls while conducting the sound-azimuth discrimination task. Lead-exposure also degraded the sound-azimuth selectivity of neurons in the primary auditory cortex. Subsequent sound-azimuth discrimination training, however, restored to nearly normal the lead-degraded cortical azimuth selectivity. This reversal of cortical spatial fidelity was paralleled by changes in cortical expression of certain excitatory and inhibitory neurotransmitter receptor subunits. These results in a rodent model demonstrate the persisting neurotoxic effects of early lead-exposure on behavioral and cortical neuronal processing of spatial information of sound. They also indicate that attention-demanding auditory training may remediate lead-induced cortical neurological deficits even after these deficits have occurred.
Collapse
Affiliation(s)
- Xia Liu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China
| | - Fanfan Wei
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China
| | - Yuan Cheng
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| | - Yifan Zhang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| | - Guoqiang Jia
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| | - Jie Zhou
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| | - Min Zhu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| | - Ye Shan
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China
| | - Xinde Sun
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China
| | - Liping Yu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China
| | | | - Diana I Lurie
- Center for Structural and Functional Neuroscience, Center for Environmental Health Sciences, Department of Biomedical & Pharmaceutical Sciences, College of Health Professions and Biomedical Sciences, University of Montana, Missoula, MT, USA
| | - Qingyin Zheng
- Transformative Otology and Neuroscience Center, Binzhou Medical University, Yantai, China
| | - Xiaoming Zhou
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, Institute of Cognitive Neuroscience, Collaborative Innovation Center for Brain Science, School of Life Sciences, East China Normal University, Shanghai, China.,New York University-East China Normal University Institute of Brain and Cognitive Science, New York University-Shanghai, Shanghai, China
| |
Collapse
|
9
|
Xia C, Yin M, Pan P, Fang F, Zhou Y, Ji Y. Long-term exposure to moderate noise induces neural plasticity in the infant rat primary auditory cortex. Anim Cells Syst (Seoul) 2019; 23:260-269. [PMID: 31489247 PMCID: PMC6711034 DOI: 10.1080/19768354.2019.1643782] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 06/27/2019] [Accepted: 06/27/2019] [Indexed: 11/17/2022] Open
Abstract
Previous studies have reported that rearing infant rat pups in continuous moderate-level noise delayed the formation of topographic representational order and the refinement of response selectivity in the primary auditory (A1) cortex. The present study further verified that exposure to long-term moderate-intensity white noise (70 dB sound pressure level) from postnatal day (P) 12 to P30 elevated the hearing thresholds of infant rats. Compared with age-matched control rats, noise exposure (NE) rats had elevated hearing thresholds ranging from low to high frequencies, accompanied by decreased amplitudes and increased latencies of the two initial auditory brainstem response waves. The power of raw local field potential oscillations and high-frequency β oscillation in the A1 cortex of NE rats were larger, whereas the power of high-frequency γ oscillation was smaller than that of control rats. In addition, the expression levels of five glutamate receptor (GluR) subunits in the A1 cortex of NE rats were decreased with laminar specificity. These results suggest that the altered neural excitability and decreased GluR expression may underlie the delay of functional maturation in the A1 cortex, and may have implications for the treatment of hearing impairment induced by environmental noise.
Collapse
Affiliation(s)
- Chenchen Xia
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Manli Yin
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Ping Pan
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - Fanghao Fang
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| | - You Zhou
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China.,Department of Otolaryngology-Head and Neck Surgery, Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China.,Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People's Republic of China
| | - Yonghua Ji
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai, People's Republic of China
| |
Collapse
|
10
|
Balaram P, Hackett TA, Polley DB. Synergistic Transcriptional Changes in AMPA and GABA A Receptor Genes Support Compensatory Plasticity Following Unilateral Hearing Loss. Neuroscience 2018; 407:108-119. [PMID: 30176318 DOI: 10.1016/j.neuroscience.2018.08.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/02/2018] [Accepted: 08/22/2018] [Indexed: 01/11/2023]
Abstract
Debilitating perceptual disorders including tinnitus, hyperacusis, phantom limb pain and visual release hallucinations may reflect aberrant patterns of neural activity in central sensory pathways following a loss of peripheral sensory input. Here, we explore short- and long-term changes in gene expression that may contribute to hyperexcitability following a sudden, profound loss of auditory input from one ear. We used fluorescence in situ hybridization to quantify mRNA levels for genes encoding AMPA and GABAA receptor subunits (Gria2 and Gabra1, respectively) in single neurons from the inferior colliculus (IC) and auditory cortex (ACtx). Thirty days after unilateral hearing loss, Gria2 levels were significantly increased while Gabra1 levels were significantly decreased. Transcriptional rebalancing was more pronounced in ACtx than IC and bore no obvious relationship to the degree of hearing loss. By contrast to the opposing, synergistic shifts in Gria2 and Gabra1 observed 30 days after hearing loss, we found that transcription levels for both genes were equivalently reduced after 5 days of hearing loss, producing no net change in the excitatory/inhibitory transcriptional balance. Opposing transcriptional shifts in AMPA and GABA receptor genes that emerge several weeks after a peripheral insult could promote both sensitization and disinhibition to support a homeostatic recovery of neural activity following auditory deprivation. Imprecise transcriptional changes could also drive the system toward perceptual hypersensitivity, degraded temporal processing and the irrepressible perception of non-existent environmental stimuli, a trio of perceptual impairments that often accompany chronic sensory deprivation.
Collapse
Affiliation(s)
- P Balaram
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston MA 02114, USA; Dept. of Otolaryngology, Harvard Medical School, Boston MA 02114, USA
| | - T A Hackett
- Dept. of Hearing and Speech Sciences, Vanderbilt Bill Wilkerson Center for Otolaryngology and Communication Sciences, Vanderbilt University Medical Center, Nashville TN 37232 USA
| | - D B Polley
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, Boston MA 02114, USA; Dept. of Otolaryngology, Harvard Medical School, Boston MA 02114, USA.
| |
Collapse
|
11
|
Pysanenko K, Bureš Z, Lindovský J, Syka J. The Effect of Complex Acoustic Environment during Early Development on the Responses of Auditory Cortex Neurons in Rats. Neuroscience 2018; 371:221-228. [DOI: 10.1016/j.neuroscience.2017.11.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/29/2017] [Accepted: 11/30/2017] [Indexed: 01/12/2023]
|
12
|
Modulation of azimuth tuning plasticity in rat primary auditory cortex by medial prefrontal cortex. Neuroscience 2017; 347:36-47. [PMID: 28188851 DOI: 10.1016/j.neuroscience.2017.01.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 01/11/2017] [Accepted: 01/27/2017] [Indexed: 11/21/2022]
Abstract
Neurons in the primary auditory cortex (A1) of adult animals exhibit short-term plasticity of frequency selectivity and tonotopic organization in behavioral contexts ranging from classical conditioning to attention tasks. However, it is still largely unknown whether short-term plasticity of spatial tuning takes place in A1 of adult animals and whether this spatial turning plasticity in A1 of adults is mediated by medial prefrontal cortex (mPFC) as there are reciprocal connection between mPFC and auditory cortex (AC). In the present study, we used extracellular recordings to test whether azimuth tuning in A1 of anesthetized rats can be reshaped by repeated sound stimuli at neurons' non-preferred azimuth. We also identified whether and how such A1 azimuth tuning plasticity was modulated by the neural activities of mPFC. Our results showed that A1 neurons in adult rats have azimuth tuning plasticity when repeated acoustic stimuli were delivered at the azimuth with a deviation by less than 15° from the best azimuth (BA). The BA shifted toward the exposure azimuth when repeated acoustic stimuli were played for 20-60min and plasticity decayed within one hour. The less the angle deviated from the BA, the shorter exposure time and longer decay time were required to induce azimuth tuning plasticity. Neural activity in mPFC modulated azimuth tuning plasticity of A1 neurons as reflected by the shorter induction time when mPFC was activated by focal electrical stimulation and the longer induction time when mPFC was inactivated by drug application. Our results suggest that spatial location selectivity in A1 neurons remains plastic in mature animals and that short-term plasticity of spatial tuning can be modulated by the neural activities of mPFC.
Collapse
|
13
|
Surface expression of hippocampal NMDA GluN2B receptors regulated by fear conditioning determines its contribution to memory consolidation in adult rats. Sci Rep 2016; 6:30743. [PMID: 27487820 PMCID: PMC4973269 DOI: 10.1038/srep30743] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 07/07/2016] [Indexed: 11/16/2022] Open
Abstract
The number and subtype composition of N-methyl-d-aspartate receptor (NMDAR) at synapses determines their functional properties and role in learning and memory. Genetically increased or decreased amount of GluN2B affects hippocampus-dependent memory in the adult brain. But in some experimental conditions (e.g., memory elicited by a single conditioning trial (1 CS-US)), GluN2B is not a necessary factor, which indicates that the precise role of GluN2B in memory formation requires further exploration. Here, we examined the role of GluN2B in the consolidation of fear memory using two training paradigms. We found that GluN2B was only required for the consolidation of memory elicited by five conditioning trials (5 CS-US), not by 1 CS-US. Strikingly, the expression of membrane GluN2B in CA1was training-strength-dependently increased after conditioning, and that the amount of membrane GluN2B determined its involvement in memory consolidation. Additionally, we demonstrated the increases in the activities of cAMP, ERK, and CREB in the CA1 after conditioning, as well as the enhanced intrinsic excitability and synaptic efficacy in CA1 neurons. Up-regulation of membrane GluN2B contributed to these enhancements. These studies uncover a novel mechanism for the involvement of GluN2B in memory consolidation by its accumulation at the cell surface in response to behavioral training.
Collapse
|
14
|
Rahati M, Nozari M, Eslami H, Shabani M, Basiri M. Effects of enriched environment on alterations in the prefrontal cortex GFAP- and S100B-immunopositive astrocytes and behavioral deficits in MK-801-treated rats. Neuroscience 2016; 326:105-116. [PMID: 27063100 DOI: 10.1016/j.neuroscience.2016.03.065] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 03/17/2016] [Accepted: 03/29/2016] [Indexed: 10/22/2022]
Abstract
A plethora of studies have indicated that enriched environment (EE) paradigm provokes plastic and morphological changes in astrocytes with accompanying increments of their density and positively affects the behavior of rodents. We also previously documented that EE could be employed to preclude several behavioral abnormalities, mainly cognitive deficits, attributed to postnatal N-methyl-d-aspartate (NMDA) receptor antagonist (MK-801) treatment, as a rodent model of schizophrenia (SCH) aspects. Given this, the current study quantitatively investigated the number of cells, presumed to be astrocytes, expressing two astroglia-associated proteins (S100B and glial fibrillary acidic protein (GFAP)) by immunohistochemistry in the prefrontal cortex (PFC), along with anxiety and passive avoidance (PA) learning behaviors by utilizing elevated plus maze (EPM) and shuttle-box tests, in MK-801-treated male wistar rats submitted to EE and non-EE rats. Following a treatment regime of sub-chronic MK-801 (1.0mg/kg i.p. daily for five consecutive days from postnatal day (P) 6), S-100B-positive cells and anxiety level were markedly increased, while the GFAP-positive cells and PA learning were notably attenuated. The trend of diminished GFAP-immunopositive cells and elevated S100B-immunostained cells in the PFC was reversed in the SCH-like rats by exposure of animals to EE, commencing from birth up to the time of experiments on P28-85. Additionally, EE exhibited an ameliorating effect on the behavioral abnormalities evoked by MK-801. Overall, present findings support that improper astrocyte functioning and behavioral changes, reminiscent of the many facets of SCH, occur consequential to repetitive administration of MK-801 and that raising rat pups in an EE mitigates these alterations.
Collapse
Affiliation(s)
- M Rahati
- Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran; Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - M Nozari
- Department of Physiology, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - H Eslami
- Department of Pharmacology, Molecular Medicine Research Center, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - M Shabani
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - M Basiri
- Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran; Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran.
| |
Collapse
|
15
|
Jiang C, Xu X, Yu L, Xu J, Zhang J. Environmental enrichment rescues the degraded auditory temporal resolution of cortical neurons induced by early noise exposure. Eur J Neurosci 2015; 42:2144-54. [DOI: 10.1111/ejn.12975] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 06/02/2015] [Accepted: 06/02/2015] [Indexed: 12/26/2022]
Affiliation(s)
- Cuiping Jiang
- Key Laboratory of Brain Functional Genomics; Ministry of Education; Shanghai Key Laboratory of Brain Functional Genomics; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai; School of Life Sciences; East China Normal University; Shanghai 200062 China
| | - Xiaoxiao Xu
- Key Laboratory of Brain Functional Genomics; Ministry of Education; Shanghai Key Laboratory of Brain Functional Genomics; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai; School of Life Sciences; East China Normal University; Shanghai 200062 China
| | - Liping Yu
- Key Laboratory of Brain Functional Genomics; Ministry of Education; Shanghai Key Laboratory of Brain Functional Genomics; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai; School of Life Sciences; East China Normal University; Shanghai 200062 China
| | - Jinghong Xu
- Key Laboratory of Brain Functional Genomics; Ministry of Education; Shanghai Key Laboratory of Brain Functional Genomics; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai; School of Life Sciences; East China Normal University; Shanghai 200062 China
| | - Jiping Zhang
- Key Laboratory of Brain Functional Genomics; Ministry of Education; Shanghai Key Laboratory of Brain Functional Genomics; NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai; School of Life Sciences; East China Normal University; Shanghai 200062 China
| |
Collapse
|
16
|
Mother's voice and heartbeat sounds elicit auditory plasticity in the human brain before full gestation. Proc Natl Acad Sci U S A 2015; 112:3152-7. [PMID: 25713382 DOI: 10.1073/pnas.1414924112] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Brain development is largely shaped by early sensory experience. However, it is currently unknown whether, how early, and to what extent the newborn's brain is shaped by exposure to maternal sounds when the brain is most sensitive to early life programming. The present study examined this question in 40 infants born extremely prematurely (between 25- and 32-wk gestation) in the first month of life. Newborns were randomized to receive auditory enrichment in the form of audio recordings of maternal sounds (including their mother's voice and heartbeat) or routine exposure to hospital environmental noise. The groups were otherwise medically and demographically comparable. Cranial ultrasonography measurements were obtained at 30 ± 3 d of life. Results show that newborns exposed to maternal sounds had a significantly larger auditory cortex (AC) bilaterally compared with control newborns receiving standard care. The magnitude of the right and left AC thickness was significantly correlated with gestational age but not with the duration of sound exposure. Measurements of head circumference and the widths of the frontal horn (FH) and the corpus callosum (CC) were not significantly different between the two groups. This study provides evidence for experience-dependent plasticity in the primary AC before the brain has reached full-term maturation. Our results demonstrate that despite the immaturity of the auditory pathways, the AC is more adaptive to maternal sounds than environmental noise. Further studies are needed to better understand the neural processes underlying this early brain plasticity and its functional implications for future hearing and language development.
Collapse
|
17
|
Zhu X, Liu X, Wei F, Wang F, Merzenich MM, Schreiner CE, Sun X, Zhou X. Perceptual Training Restores Impaired Cortical Temporal Processing Due to Lead Exposure. ACTA ACUST UNITED AC 2014; 26:334-345. [PMID: 25405943 DOI: 10.1093/cercor/bhu258] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Low-level lead exposure is a risk factor for cognitive and learning disabilities in children and has been specifically associated with deficits in auditory temporal processing that impair aural language and reading abilities. Here, we show that rats exposed to low levels of lead in early life display a significant behavioral impairment in an auditory temporal rate discrimination task. Lead exposure also results in a degradation of the neuronal repetition-rate following capacity and response synchronization in primary auditory cortex. A modified go/no-go repetition-rate discrimination task applied in adult animals for ∼50 days nearly restores to normal these lead-induced deficits in cortical temporal fidelity. Cortical expressions of parvalbumin, brain-derived neurotrophic factor, and NMDA receptor subunits NR2a and NR2b, which are down-regulated in lead-exposed animals, are also partially reversed with training. These studies in an animal model identify the primary auditory cortex as a novel target for low-level lead exposure and demonstrate that perceptual training can ameliorate lead-induced deficits in cortical discrimination between sound sequences.
Collapse
Affiliation(s)
- Xiaoqing Zhu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China
| | - Xia Liu
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China
| | - Fanfan Wei
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China
| | - Fang Wang
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China
| | - Michael M Merzenich
- Coleman Memorial Laboratory, Keck Center for Integrative Neuroscience, University of California, San Francisco, CA 94143, USA
| | - Christoph E Schreiner
- Coleman Memorial Laboratory, Keck Center for Integrative Neuroscience, University of California, San Francisco, CA 94143, USA
| | - Xinde Sun
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China
| | - Xiaoming Zhou
- Key Laboratory of Brain Functional Genomics of Ministry of Education, Shanghai Key Laboratory of Brain Functional Genomics, School of Life Sciences, East China Normal University, Shanghai 200062, China.,NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai, Shanghai 200062, China
| |
Collapse
|
18
|
An enriched environment ameliorates memory impairments in PACAP-deficient mice. Behav Brain Res 2014; 272:269-78. [DOI: 10.1016/j.bbr.2014.07.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 12/21/2022]
|
19
|
Environmental acoustic enrichment promotes recovery from developmentally degraded auditory cortical processing. J Neurosci 2014; 34:5406-15. [PMID: 24741032 DOI: 10.1523/jneurosci.5310-13.2014] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
It has previously been shown that environmental enrichment can enhance structural plasticity in the brain and thereby improve cognitive and behavioral function. In this study, we reared developmentally noise-exposed rats in an acoustic-enriched environment for ∼4 weeks to investigate whether or not enrichment could restore developmentally degraded behavioral and neuronal processing of sound frequency. We found that noise-exposed rats had significantly elevated sound frequency discrimination thresholds compared with age-matched naive rats. Environmental acoustic enrichment nearly restored to normal the behavioral deficit resulting from early disrupted acoustic inputs. Signs of both degraded frequency selectivity of neurons as measured by the bandwidth of frequency tuning curves and decreased long-term potentiation of field potentials recorded in the primary auditory cortex of these noise-exposed rats also were reversed partially. The observed behavioral and physiological effects induced by enrichment were accompanied by recovery of cortical expressions of certain NMDA and GABAA receptor subunits and brain-derived neurotrophic factor. These studies in a rodent model show that environmental acoustic enrichment promotes recovery from early noise-induced auditory cortical dysfunction and indicate a therapeutic potential of this noninvasive approach for normalizing neurological function from pathologies that cause hearing and associated language impairments in older children and adults.
Collapse
|
20
|
Abstract
Although training-based auditory cortical plasticity in the adult brain has been previously demonstrated in multiparametric sound domains, neurochemical mechanisms responsible for this form of plasticity are not well understood. In this study, we trained adult rats to identify a target sound stimulus at a specific azimuth angle by using a reward-contingent auditory discrimination task. We found that auditory spatial discrimination training significantly enhanced representation of sound azimuths in the primary auditory cortex, as shown by sharper azimuth-selective curves and more evenly distributed best angles of cortical neurons. Training also facilitated long-term potentiation of field potentials in the primary auditory cortex induced by theta burst stimulation of the white matter. In parallel, there were significant alterations in expression levels of certain cortical GABA(A) and NMDA receptor subunits, resulting in a marked decrease in the level of GABA(A) relative to NMDA receptors. These changes in the expression profile of inhibitory and excitatory neurotransmitter receptor subunits might enhance synaptic transmission, thereby facilitating training-induced cortical plasticity in the spatial domain.
Collapse
|
21
|
Guo F, Zhang J, Zhu X, Cai R, Zhou X, Sun X. Auditory discrimination training rescues developmentally degraded directional selectivity and restores mature expression of GABA(A) and AMPA receptor subunits in rat auditory cortex. Behav Brain Res 2012; 229:301-7. [PMID: 22306199 DOI: 10.1016/j.bbr.2011.12.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Revised: 12/27/2011] [Accepted: 12/28/2011] [Indexed: 11/25/2022]
Abstract
Auditory frequency discrimination training can remediate deteriorated frequency representations and temporal information processing in the adult primary auditory cortex induced by early post-natal pulsed noise exposure. In this study, we investigated the neural mechanisms underlying the restoration of directional selectivity by auditory spatial discrimination training. Rats exposed to pulsed noise during a post-natal critical period demonstrated reduced auditory directional selectivity but could be successfully trained to identify a target sound stimulus at a specific azimuth angle using a reward-contingent auditory discrimination task (EXP rats). In contrast, rats passively exposed to the training procedure but no reward for correct identification of the azimuth angle (PNR rats) showed no improvement and behavioral performance remained significantly below EXP rats and control (CON) rats reared under a normal sonic environment. The expression levels of GABA(A) receptor subunits α1, α3, β2, and β3, and the AMPA GluR2 subunit were significantly altered in the auditory cortex of untrained noise-raised (NR and PNR) rats compared to age-matched CON rats, while trained noise-raised (EXP) rats exhibited levels of expression not significantly different from CON rats. Thus, reward-contingent sound-azimuth discrimination training may remediate directional selectivity by restoring the proper expression profile of neurotransmitter receptor subunits in the auditory cortex, allowing for normal spatial selectivity by cortical neurons. The development of auditory directional selectivity depends on the regulated expression of these excitatory and inhibitory neurotransmitter receptor subunits; early pulsed noise may disrupt the normal development of directional selectivity by interfering with receptor expression.
Collapse
Affiliation(s)
- Fei Guo
- School of Life Science, Key Laboratory of Brain Functional Genomics, Ministry of Education, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
| | | | | | | | | | | |
Collapse
|
22
|
Developmentally degraded directional selectivity of the auditory cortex can be restored by auditory discrimination training in adults. Behav Brain Res 2011; 225:596-602. [PMID: 21893102 DOI: 10.1016/j.bbr.2011.08.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 08/20/2011] [Accepted: 08/23/2011] [Indexed: 11/24/2022]
Abstract
Sound localization is one of the most important tasks performed by the auditory system. Studies have shown that intensive training can remediate deteriorated frequency representations and temporal information processing in the adult primary auditory cortex (A1) induced by early post-natal pulsed noise exposure. Here we demonstrate that intensive sound location discrimination training improved the dysfunctional sound azimuth selectivity degraded by early post-natal pulsed noise exposure. Rats exposed to pulsed white noise during a post-natal critical period were successfully trained to identify a target sound stimulus with specific azimuth angle that changed daily on a random schedule. Consistent with recovery of behavioral accuracy for sound-azimuth discriminations, we found that the average angular range (AR) of A1 neuronal azimuth selective curves in trained noise-raised rats was not significantly different from that measured in control rats, while the average AR of A1 neurons in untrained noise-raised rats was significantly higher, indicating that these neurons were less direction selective. Directional selectivity of A1 neurons was normalized by training, thus demonstrating the benefits of sensory discrimination training as a strategy for restoring auditory function in adult mammals damaged by sensory disruption during critical periods of cortical development.
Collapse
|