There is growing evidence suggests that noise-induced cochlear damage may lead to hyperexcitability in the central auditory system(CAS)which may give rise to tinnitus.However,the correlation between the onset of the n...There is growing evidence suggests that noise-induced cochlear damage may lead to hyperexcitability in the central auditory system(CAS)which may give rise to tinnitus.However,the correlation between the onset of the neurophysiological changes in the CAS and the onset of tinnitus has not been well studied.To investigate this relationship,chronic electrodes were implanted into the auditory cortex(AC) and sound evoked activities were measured from awake rats before and after noise exposure.The auditory brainstem response(ABR) was used to assess the degree of noise-induced hearing loss.Tinnitus was evaluated by measuring gap-induced prepulse inhibition(gap-PPI).Rats were exposed monaurally to a high-intensity narrowband noise centered at 12 kHz at a level of 120 dB SPL for 1 h.After the noise exposure,all the rats developed either permanent(>2 weeks) or temporary(<3 days) hearing loss in the exposed ear(s).The AC amplitudes increased significantly 4 h after the noise exposure.Most of the exposed rats also showed decreased gap-PPI.The post-exposure AC enhancement showed a positive correlation with the amount of hearing loss.The onset of tinnitus-like behavior was happened after the onset of AC enhancement.展开更多
Objective Blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) was used to study activation signals in the brain cortex evoked by tone stimulation in patients with tinnitus for its poten...Objective Blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) was used to study activation signals in the brain cortex evoked by tone stimulation in patients with tinnitus for its potential utility as an objective indicator of tinnitus. Methods BOLD-fMRI examination was conducted in 7 patients with chronic tinnitus and 15 control subjects. The activation signal in the brain cortex was recorded. Results Significant activation was found in temporal lobe in control subjects, with greater signal volume and intensity on the contralateral than ipsilateral auditory cortex (P < 0.01). However, there was no discernable patterns in the anatomical location, volume and intensity of cortical activation signals in patients with chronic tinnitus. Conclusions Patients with chronic tinnitus may have abnormal neural activities in the auditory cortex.展开更多
Major depressive disorder(MDD),characterized by anhedonia,loss of motivation,behavioral despair,and cognitive abnormalities[1],stands as the second leading cause of disability worldwide[2]owing to its heightened preva...Major depressive disorder(MDD),characterized by anhedonia,loss of motivation,behavioral despair,and cognitive abnormalities[1],stands as the second leading cause of disability worldwide[2]owing to its heightened prevalence,suicide rates,and recurrence[3].Empirical evidence and clinical observations have substantiated the notion that patients with MDD often exhibit compromised auditory perception[4].展开更多
Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-...Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-term auditory deprivation and stimulability of auditory cortex in non habilitated congenitally deaf adolescents and adults using CAEPs.Methods and Results:A total of 27 non-habilitated congenitally deaf adolescents/adults with age and gender matched normal hearing adolescents/adults participated in the study.The congenitally deaf group was fitted with high gain hearing aids(first fit).Further,the CAEPs were recorded.The obtained CAEP components were assessed for group effect,source and topographical differences.The between group analysis for CAEP responses showed a significant difference only for P2 latency and amplitude.The source analysis revealed that,in the normal hearing group for CAEPs,the sources were within the temporal regions.However,in the congenitally deaf group,along with the temporal cortex,the bilateral prefrontal cortex also was activated.Conclusion:The findings revealed that it is possible to stimulate and evoke a matured CAEP response from a long deprived auditory system with adequate acoustic stimulation.The presence of CAEP responses is indicative of the functionality of the innate auditory pathway and the crossmodal plasticity in long auditory deprived individuals.展开更多
Tinnitus can be described as the conscious perception of sound without external stimulation,and it is often accompanied by anxiety,depression,and insomnia.Current clinical treatments for tinnitus are ineffective.Altho...Tinnitus can be described as the conscious perception of sound without external stimulation,and it is often accompanied by anxiety,depression,and insomnia.Current clinical treatments for tinnitus are ineffective.Although recent studies have indicated that the caudateputamen nucleus may be a sensory gating area involved in noise elimination in tinnitus,the underlying mechanisms of this disorder are yet to be determined.To investigate the potential role of the caudate-putamen nucleus in experimentally induced tinnitus,we created a rat model of tinnitus induced by intraperitoneal administration of 350 mg/kg sodium salicylate.Our results revealed that the mean spontaneous firing rate of the caudate-putamen nucleus was increased by sodium salicylate treatment,while dopamine levels were decreased.In addition,electrical stimulation of the caudate-putamen nucleus markedly reduced the spontaneous firing rate of neurons in the primary auditory cortex.These findings suggest that the caudate-putamen nucleus plays a sensory gating role in sodium salicylate-induced tinnitus.This study was approved by the Institutional Animal Care and Use Committee of Peking University Health Science Center(approval No.A2010031)on December 6,2017.展开更多
Developmental exposure to bisphenol A(BPA),an endocrine-disrupting contaminant,impairs cognitive function in both animals and humans.However,whether BPA affects the development of primary sensory systems,which are the...Developmental exposure to bisphenol A(BPA),an endocrine-disrupting contaminant,impairs cognitive function in both animals and humans.However,whether BPA affects the development of primary sensory systems,which are the first to mature in the cortex,remains largely unclear.Using the rat as a model,we aimed to record the physiological and structural changes in the primary auditory cortex(A1)following lactational BPA exposure and their possible effects on behavioral outcomes.We found that BPA-exposed rats showed significant behavioral impairments when performing a sound temporal rate discrimination test.A significant alteration in spectral and temporal processing was also recorded in their A1,manifested as degraded frequency selectivity and diminished stimulus rate-following by neurons.These post-exposure effects were accompanied by changes in the density and maturity of dendritic spines in A1.Our findings demonstrated developmental impacts of BPA on auditory cortical processing and auditory-related discrimination,particularly in the temporal domain.Thus,the health implications for humans associated with early exposure to endocrine disruptors such as BPA merit more careful examination.展开更多
文摘There is growing evidence suggests that noise-induced cochlear damage may lead to hyperexcitability in the central auditory system(CAS)which may give rise to tinnitus.However,the correlation between the onset of the neurophysiological changes in the CAS and the onset of tinnitus has not been well studied.To investigate this relationship,chronic electrodes were implanted into the auditory cortex(AC) and sound evoked activities were measured from awake rats before and after noise exposure.The auditory brainstem response(ABR) was used to assess the degree of noise-induced hearing loss.Tinnitus was evaluated by measuring gap-induced prepulse inhibition(gap-PPI).Rats were exposed monaurally to a high-intensity narrowband noise centered at 12 kHz at a level of 120 dB SPL for 1 h.After the noise exposure,all the rats developed either permanent(>2 weeks) or temporary(<3 days) hearing loss in the exposed ear(s).The AC amplitudes increased significantly 4 h after the noise exposure.Most of the exposed rats also showed decreased gap-PPI.The post-exposure AC enhancement showed a positive correlation with the amount of hearing loss.The onset of tinnitus-like behavior was happened after the onset of AC enhancement.
文摘Objective Blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) was used to study activation signals in the brain cortex evoked by tone stimulation in patients with tinnitus for its potential utility as an objective indicator of tinnitus. Methods BOLD-fMRI examination was conducted in 7 patients with chronic tinnitus and 15 control subjects. The activation signal in the brain cortex was recorded. Results Significant activation was found in temporal lobe in control subjects, with greater signal volume and intensity on the contralateral than ipsilateral auditory cortex (P < 0.01). However, there was no discernable patterns in the anatomical location, volume and intensity of cortical activation signals in patients with chronic tinnitus. Conclusions Patients with chronic tinnitus may have abnormal neural activities in the auditory cortex.
基金supported by the Open Project of State Key Laboratory of Natural Medicines(SKLNMKF202209)the National Natural Science Foundation of China(Nos:82074110 and 82274193)。
文摘Major depressive disorder(MDD),characterized by anhedonia,loss of motivation,behavioral despair,and cognitive abnormalities[1],stands as the second leading cause of disability worldwide[2]owing to its heightened prevalence,suicide rates,and recurrence[3].Empirical evidence and clinical observations have substantiated the notion that patients with MDD often exhibit compromised auditory perception[4].
文摘Objective:The effect of long term auditory deprivation on Cortical Auditory Evoked Potentials(CAEPs)especially in human models is not well explored.Hence,the current study was aimed to investigate the effects of long-term auditory deprivation and stimulability of auditory cortex in non habilitated congenitally deaf adolescents and adults using CAEPs.Methods and Results:A total of 27 non-habilitated congenitally deaf adolescents/adults with age and gender matched normal hearing adolescents/adults participated in the study.The congenitally deaf group was fitted with high gain hearing aids(first fit).Further,the CAEPs were recorded.The obtained CAEP components were assessed for group effect,source and topographical differences.The between group analysis for CAEP responses showed a significant difference only for P2 latency and amplitude.The source analysis revealed that,in the normal hearing group for CAEPs,the sources were within the temporal regions.However,in the congenitally deaf group,along with the temporal cortex,the bilateral prefrontal cortex also was activated.Conclusion:The findings revealed that it is possible to stimulate and evoke a matured CAEP response from a long deprived auditory system with adequate acoustic stimulation.The presence of CAEP responses is indicative of the functionality of the innate auditory pathway and the crossmodal plasticity in long auditory deprived individuals.
基金supported by the National Natural Science Foundation of China,Nos.21790391(to LQM)and 81870727(to FRM).
文摘Tinnitus can be described as the conscious perception of sound without external stimulation,and it is often accompanied by anxiety,depression,and insomnia.Current clinical treatments for tinnitus are ineffective.Although recent studies have indicated that the caudateputamen nucleus may be a sensory gating area involved in noise elimination in tinnitus,the underlying mechanisms of this disorder are yet to be determined.To investigate the potential role of the caudate-putamen nucleus in experimentally induced tinnitus,we created a rat model of tinnitus induced by intraperitoneal administration of 350 mg/kg sodium salicylate.Our results revealed that the mean spontaneous firing rate of the caudate-putamen nucleus was increased by sodium salicylate treatment,while dopamine levels were decreased.In addition,electrical stimulation of the caudate-putamen nucleus markedly reduced the spontaneous firing rate of neurons in the primary auditory cortex.These findings suggest that the caudate-putamen nucleus plays a sensory gating role in sodium salicylate-induced tinnitus.This study was approved by the Institutional Animal Care and Use Committee of Peking University Health Science Center(approval No.A2010031)on December 6,2017.
基金the National NaturalScienceFoundationofChina(32171134and 32161160325)the National Science and Technology Innovation 2030 Major Program(2022ZD0204804)+2 种基金a Project of Shanghai Science and Technology Commission(21490713200)the Program of Introducing Talents of Discipline to Universities(B16018)a matching fund from the NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai.
文摘Developmental exposure to bisphenol A(BPA),an endocrine-disrupting contaminant,impairs cognitive function in both animals and humans.However,whether BPA affects the development of primary sensory systems,which are the first to mature in the cortex,remains largely unclear.Using the rat as a model,we aimed to record the physiological and structural changes in the primary auditory cortex(A1)following lactational BPA exposure and their possible effects on behavioral outcomes.We found that BPA-exposed rats showed significant behavioral impairments when performing a sound temporal rate discrimination test.A significant alteration in spectral and temporal processing was also recorded in their A1,manifested as degraded frequency selectivity and diminished stimulus rate-following by neurons.These post-exposure effects were accompanied by changes in the density and maturity of dendritic spines in A1.Our findings demonstrated developmental impacts of BPA on auditory cortical processing and auditory-related discrimination,particularly in the temporal domain.Thus,the health implications for humans associated with early exposure to endocrine disruptors such as BPA merit more careful examination.
