Background: We have been performing a canalith repositioning procedure for benign paroxysmal positional vertigo. When we adopted the Epley maneuver for posterior semicircular canal type, and affected-ear-up 90° m...Background: We have been performing a canalith repositioning procedure for benign paroxysmal positional vertigo. When we adopted the Epley maneuver for posterior semicircular canal type, and affected-ear-up 90° maneuver for lateral semicircular canal type, we noticed that no nystagmus occurred in the sitting position just after treatment. Despite direct excitation to the utricle by the pathological debris, none of the subjects complained of dizziness. Thus, we hypothesized that nystagmus and dizziness do not occur by stimulation of the otolith organs. Objective: The aim of the study was to observe and record the eye movements induced by the otolith organs to confirm our hypothesis. Materials and Methods: Twelve healthy humans were tested. In the sitting position, the head was tilted to the right ear by 45° and vice versa. Afterward, the head was bent forward by 90° (nose-down), and the subject’s seat was reclined to the head-hanging position. Each position was kept for five seconds. We interviewed the subjects to assess their dizziness. Results: None of the subjects showed nystagmus and complained of dizziness in every position. Conclusions: Nystagmus does not occur by the stimulation to the otolith organs;therefore, ocular counter-rolling is a semicircular canal ocular reflex.展开更多
Vestibular evoked myogenic potential (VEMP), is an electromyographic response of vestibular origin evoked by sound, vibration or electrical stimulation. VEMP is widely used as a clinical test of the otolith organs. ...Vestibular evoked myogenic potential (VEMP), is an electromyographic response of vestibular origin evoked by sound, vibration or electrical stimulation. VEMP is widely used as a clinical test of the otolith organs. Now-adays, two kinds of VEMP, cervical VEMP (cVEMP) and ocular VEMP (oVEMP) are clinically used. cVEMP is a test of sacculo-collic refex while oVEMP is a test of utri-culo-ocular refex. Absence of responses, large interau-ral asymmetry of amplitudes, prolonged peak latencies, and abnormal thresholds of responses are regarded as abnormal responses. Clinical application to various diseases of the vestibular system was performed. Using VEMP, a new type of vestibular neuritis, inferior ves-tibular neuritis was established. A prominent feature of VEMP in Meniere’s disease is a shift of a preferred fre-quency in cVEMP. The whole aspects of VEMP fndings in patients with benign paroxysmal positional vertigo are not clarifed yet. Sensitivity of cVEMP to vestibular schwannoma was 80.0%, while specifcity was 52.7%. Concerning diagnosis of superior canal dehiscence syn-drome (SCDS), oVEMP to air-conducted sound is the most helpful. Augmentation of oVEMP responses is a prominent feature in SCDS. I also presented “idiopathic otolithic vertigo”, which I proposed as a new clinical en-tity based on VEMP fndings. Some patients complained of lateral tilting sensation in the roll plane, or tilting or translational sensation in the pitch plane without rota-tory vertigo. Majority of patients with these symptoms had absent or decreased responses of oVEMP and/or cVEMP. I proposed that these patients could be diag-nosed as having “idiopathic otolithic vertigo”.展开更多
Objective The macula lagena in birds is located at the apical end of the cochlea and contains many tiny otoliths. The macula lagena is innervated and has neural projections to the brainstem, but its physiological func...Objective The macula lagena in birds is located at the apical end of the cochlea and contains many tiny otoliths. The macula lagena is innervated and has neural projections to the brainstem, but its physiological function is still unclear. It remains disputable that it is because otoliths in the lagena are rich in elements Fe and Zn that birds can obtain geomagnetic information for homing. To clarify this issue, we carried out a study to determine whether or not otoliths in the lagena of homing pigeons are richer in magnetic elements than those in the saccule and the utricle. Methods The contents of ferromagnetic elements (Fe, Co, Ni) and other metal elements in lagenal otoliths of adult homing pigeons were precisely analyzed with inductively coupled plasma mass spectrometry (ICP-MS) of high sensitivity, and then they were compared with those in saccular and utricular otoliths (all the contents were normalized to Ca). Results In adult homing pigeons, the contents of ferromagnetic elements (Fe, Co, Ni) in lagenal otoliths were less than 0.7% (normalized to Ca element) and were the same order in magnitude as those in saccular and utricular otoliths. The content of Fe in lagenal otoliths was not significantly different from that in utricular otoliths and was even lower than that in saccular otoliths. The content of Co in lagenal otoliths was lower than that in saccular otoliths and higher than that in utricular otoliths. The content of Ni in lagenal otoliths was not significantly different from that in saccular otoliths and was higher than that in utricular otoliths. The contents of other metal elements Na, Mg, K, Al, Mn and Pb in lagenal otoliths were not significantly different from those in utricular and saccular otoliths. The contents of metal elements Zn, Ba and Cu in lagenal otoliths were lower than those in saccular otoliths. Conclusion The contents of magnetic elements in lagenal otoliths of homing pigeons are not much higher than those in utricular and saccular otoliths, which does not support the hypothesis that birds depend on high contents of Fe and Zn in lagenal otoliths for sensation of geomagnetic information. Similarities in morphology, element ingredient and element content between lagenal otoliths and utricular otoliths suggest that the two types of otolithic organs may play similar roles in sensing gravitational and acceleration signals.展开更多
The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has beco...The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has become a good model for investigating the neural and endocrine mechanisms of vocal-acoustic communication.Reproduc-tively active female plainfin midshipman fish use their auditory sense to detect and locate“singing”males,which produce a multiharmonic advertisement call to attract females for spawning.The seasonal onset of male adver-tisement calling in the midshipman fish coincides with an increase in the range of frequency sensitivity of the female’s inner ear saccule,the main organ of hearing,thus leading to enhanced encoding of the dominant frequency components of male advertisement calls.Non-reproductive females treated with either testosterone or 17β-estradiol exhibit a dramatic increase in the inner ear’s frequency sensitivity that mimics the reproductive fe-male’s auditory phenotype and leads to an increased detection of the male’s advertisement call.This novel form of auditory plasticity provides an adaptable mechanism that enhances coupling between sender and receiver in vocal communication.This review focuses on recent evidence for seasonal reproductive-state and steroid-dependent plasticity of auditory frequency sensitivity in the peripheral auditory system of the midshipman fish.The potential steroid-dependent mechanism(s)that lead to this novel form of auditory and behavioral plasticity are also dis-cussed.展开更多
文摘Background: We have been performing a canalith repositioning procedure for benign paroxysmal positional vertigo. When we adopted the Epley maneuver for posterior semicircular canal type, and affected-ear-up 90° maneuver for lateral semicircular canal type, we noticed that no nystagmus occurred in the sitting position just after treatment. Despite direct excitation to the utricle by the pathological debris, none of the subjects complained of dizziness. Thus, we hypothesized that nystagmus and dizziness do not occur by stimulation of the otolith organs. Objective: The aim of the study was to observe and record the eye movements induced by the otolith organs to confirm our hypothesis. Materials and Methods: Twelve healthy humans were tested. In the sitting position, the head was tilted to the right ear by 45° and vice versa. Afterward, the head was bent forward by 90° (nose-down), and the subject’s seat was reclined to the head-hanging position. Each position was kept for five seconds. We interviewed the subjects to assess their dizziness. Results: None of the subjects showed nystagmus and complained of dizziness in every position. Conclusions: Nystagmus does not occur by the stimulation to the otolith organs;therefore, ocular counter-rolling is a semicircular canal ocular reflex.
文摘Vestibular evoked myogenic potential (VEMP), is an electromyographic response of vestibular origin evoked by sound, vibration or electrical stimulation. VEMP is widely used as a clinical test of the otolith organs. Now-adays, two kinds of VEMP, cervical VEMP (cVEMP) and ocular VEMP (oVEMP) are clinically used. cVEMP is a test of sacculo-collic refex while oVEMP is a test of utri-culo-ocular refex. Absence of responses, large interau-ral asymmetry of amplitudes, prolonged peak latencies, and abnormal thresholds of responses are regarded as abnormal responses. Clinical application to various diseases of the vestibular system was performed. Using VEMP, a new type of vestibular neuritis, inferior ves-tibular neuritis was established. A prominent feature of VEMP in Meniere’s disease is a shift of a preferred fre-quency in cVEMP. The whole aspects of VEMP fndings in patients with benign paroxysmal positional vertigo are not clarifed yet. Sensitivity of cVEMP to vestibular schwannoma was 80.0%, while specifcity was 52.7%. Concerning diagnosis of superior canal dehiscence syn-drome (SCDS), oVEMP to air-conducted sound is the most helpful. Augmentation of oVEMP responses is a prominent feature in SCDS. I also presented “idiopathic otolithic vertigo”, which I proposed as a new clinical en-tity based on VEMP fndings. Some patients complained of lateral tilting sensation in the roll plane, or tilting or translational sensation in the pitch plane without rota-tory vertigo. Majority of patients with these symptoms had absent or decreased responses of oVEMP and/or cVEMP. I proposed that these patients could be diag-nosed as having “idiopathic otolithic vertigo”.
基金supported by the National Natural Science Foundation of China(No.30470560 and 30730041)the National Basic Research Program of China (No.2007CB512306)the Knowledge Innovation Project of Chinese Academy of Sciences (No.KSCX1-YW-R-36)
文摘Objective The macula lagena in birds is located at the apical end of the cochlea and contains many tiny otoliths. The macula lagena is innervated and has neural projections to the brainstem, but its physiological function is still unclear. It remains disputable that it is because otoliths in the lagena are rich in elements Fe and Zn that birds can obtain geomagnetic information for homing. To clarify this issue, we carried out a study to determine whether or not otoliths in the lagena of homing pigeons are richer in magnetic elements than those in the saccule and the utricle. Methods The contents of ferromagnetic elements (Fe, Co, Ni) and other metal elements in lagenal otoliths of adult homing pigeons were precisely analyzed with inductively coupled plasma mass spectrometry (ICP-MS) of high sensitivity, and then they were compared with those in saccular and utricular otoliths (all the contents were normalized to Ca). Results In adult homing pigeons, the contents of ferromagnetic elements (Fe, Co, Ni) in lagenal otoliths were less than 0.7% (normalized to Ca element) and were the same order in magnitude as those in saccular and utricular otoliths. The content of Fe in lagenal otoliths was not significantly different from that in utricular otoliths and was even lower than that in saccular otoliths. The content of Co in lagenal otoliths was lower than that in saccular otoliths and higher than that in utricular otoliths. The content of Ni in lagenal otoliths was not significantly different from that in saccular otoliths and was higher than that in utricular otoliths. The contents of other metal elements Na, Mg, K, Al, Mn and Pb in lagenal otoliths were not significantly different from those in utricular and saccular otoliths. The contents of metal elements Zn, Ba and Cu in lagenal otoliths were lower than those in saccular otoliths. Conclusion The contents of magnetic elements in lagenal otoliths of homing pigeons are not much higher than those in utricular and saccular otoliths, which does not support the hypothesis that birds depend on high contents of Fe and Zn in lagenal otoliths for sensation of geomagnetic information. Similarities in morphology, element ingredient and element content between lagenal otoliths and utricular otoliths suggest that the two types of otolithic organs may play similar roles in sensing gravitational and acceleration signals.
文摘The plainfin midshipman fish(Porichthys notatus Girard,1854)is a vocal species of batrachoidid fish that gen-erates acoustic signals for intraspecific communication during social and reproductive activity and has become a good model for investigating the neural and endocrine mechanisms of vocal-acoustic communication.Reproduc-tively active female plainfin midshipman fish use their auditory sense to detect and locate“singing”males,which produce a multiharmonic advertisement call to attract females for spawning.The seasonal onset of male adver-tisement calling in the midshipman fish coincides with an increase in the range of frequency sensitivity of the female’s inner ear saccule,the main organ of hearing,thus leading to enhanced encoding of the dominant frequency components of male advertisement calls.Non-reproductive females treated with either testosterone or 17β-estradiol exhibit a dramatic increase in the inner ear’s frequency sensitivity that mimics the reproductive fe-male’s auditory phenotype and leads to an increased detection of the male’s advertisement call.This novel form of auditory plasticity provides an adaptable mechanism that enhances coupling between sender and receiver in vocal communication.This review focuses on recent evidence for seasonal reproductive-state and steroid-dependent plasticity of auditory frequency sensitivity in the peripheral auditory system of the midshipman fish.The potential steroid-dependent mechanism(s)that lead to this novel form of auditory and behavioral plasticity are also dis-cussed.