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1.
2.
Summary Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and nonconcussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n=11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n=11) and non-concussed controls (n=11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent postconcussional syndrome. 相似文献
3.
R. J. A. M. van der Hulst A. Dreschler R. A. Tange 《European archives of oto-rhino-laryngology》1993,250(2):69-72
Summary A transcutaneous bone-conduction hearing aid was implanted in 11 patients who were not suitable for transcranial sound amplification. Audiological and surgical selection criteria were followed strictly. One device had to be explanted and minor revision surgery was needed in two cases for skin irritation and scarring. In general the aids were well tolerated but the amplification power of the external device proved to be insufficient in some patients, in whom bone conduction levels were on the borderline of the selection limits.
Correspondence to: W.A. Dreschler 相似文献
4.
噪声对耳蜗外淋巴中某些离子含量的影响 总被引:3,自引:0,他引:3
将18只豚鼠分为1个对照组和2个暴露组,分别暴露于115dB(SPL)、125dB(SPL),1.5kHz纯音0.5h,以皮层听区诱发电位为检查指标,观察暴露前后动物听力的改变,并测定了耳蜗外淋巴中Na+、K+、Ca2+、Mg2+离子含量的变化。结果表明,声暴露后各组动物听阈明显提高,且125dB组听力损失明显高于115dB组。125dB声暴露后,耳蜗外淋巴中Ca2+明显降低,而115dB组与正常对照组相比差异无显著性。声暴露对其它离子的含量没有影响。结果提示Ca2+可能与声损伤,特别是与永久性听力损失有关。 相似文献
5.
Toshinosuke Akutsu Ryota Imai Jun Saito Tomoyuki Suzuki 《Journal of artificial organs》2008,11(2):67-74
The Jyros (JR) valve and the newer On-X and MIRA valves, all installed antianatomically, were compared with the St. Jude Medical (SJM) valve in the mitral position to study the effects of valve design differences on the down-stream flow field and the associated valve closing sound. The dynamic particle image velocimetry method utilizing a high-speed video flow visualization technique was used to map the velocity field, and wavelet analysis of the sound was used to find the correlation between the ventricular flow field and the valve closing sound. Based on the experimental data, the following general conclusions can be made. In the velocity field directly below the mitral valve, where the distinct characteristic differences of the valve designs will be evident, twin symmetrical circulations were observed due to the divergent nature of the flow generated by the two inclined half-disks with the valve installed in the anti-anatomical orientation; the SJM, the On-X, and the MIRA valves generated a centrally downward circulation that opposed the valve leaflet closing movement, and resulted in relatively loud valve closing sounds. 相似文献
6.
What and where in human audition: selective deficits following focal hemispheric lesions 总被引:8,自引:0,他引:8
Clarke S Bellmann Thiran A Maeder P Adriani M Vernet O Regli L Cuisenaire O Thiran JP 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,147(1):8-15
A sound that we hear in a natural setting allows us to identify the sound source and localize it in space. The two aspects
can be disrupted independently as shown in a study of 15 patients with focal right-hemispheric lesions. Four patients were
normal in sound recognition but severely impaired in sound localization, whereas three other patients had difficulties in
recognizing sounds but localized them well. The lesions involved the inferior parietal and frontal cortices, and the superior
temporal gyrus in patients with selective sound localization deficit; and the temporal pole and anterior part of the fusiform,
inferior and middle temporal gyri in patients with selective recognition deficit. These results suggest separate cortical
processing pathways for auditory recognition and localization.
Electronic Publication 相似文献
7.
Eric I. Knudsen Phyllis F. Knudsen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,108(1):23-32
A region in the barn owl forebrain, referred to as the archistriatal gaze fields (AGF), is shown to be involved in auditory orienting behavior. In a previous study, electrical microstimulation of the AGF was shown to produce saccadic movements of the eyes and head, and anatomical data revealed that neurons in the AGF region of the archistriatum project directly to brainstem tegmental nuclei that mediate gaze changes. In this study, we investigated the effects of AGF inactivation on the auditory orienting responses of trained barn owls. The AGF and/or the optic tectum (OT) were inactivated pharmacologically using the GABAA agonist muscimol. Inactivation of the AGF alone had no effect on the probability or accuracy of orienting responses to contralateral acoustic stimuli. Inactivation of the OT alone decreased the probability of responses to contralateral stimuli, but the animals were still capable of orienting accurately toward stimuli on about 60% of the trials. Inactivation of both the AGF and the OT drastically decreased the probability of responses to 16–21% and, on the few trials that the animals did respond, there was no relationship between the final direction of gaze and the location of the stimulus. Thus, with the AGF and OT both inactivated, the animals were no longer capable of orienting accurately toward acoustic stimuli located on the contralateral side. These data confirm that the AGF is involved in gaze control and that the AGF and the OT have parallel access to gaze control circuitry in the brainstem tegmentum. In these respects, the AGF in barn owls is functionally equivalent to the frontal eye fields in primates. 相似文献
8.
Milan Stevanovic George R. Wodicka Joe D. Bourland George P. Graber Kirk S. Foster Gary C. Lantz Willis A. Tacker Allen Cymerman 《Annals of biomedical engineering》1995,23(6):720-727
Although potentially fatal increases in intracranial pressure (ICP) can occur in a number of pathological conditions, there
is no reliable and noninvasive procedure to detect ICP elevation and quantitatively monitor changes over time. In this experimental
study, the relationships between ICP elevation and the vibrational response of the head were determined. An ovine animal model
was employed in which incremental increases in ICP were elicited and directly measured through intraventricular cannulae.
At each ICP increment, a vibration source elicited a flexural response of the animal's head that was measured at four locations
on the skull using accelerometers. Spectral analysis of the responses showed changes in proportion to ICP change up to roughly
20 cm H2O (15 mm Hg) above normal; a clinically significant range. Both magnitude and phase changes at frequencies between 4 and 7
kHz correlated well (γ>0.92) with ICP across the study group. These findings suggest that the vibrational response of the
head can be used to monitor changes in ICP noninvasively. 相似文献
9.
D. W. Suobank A. P. Yoganathan E. C. Harrison W. H. Corcoran 《Medical & biological engineering & computing》1984,22(1):40-47
A comparative study was made of the sounds produced by a normal Starr-Edwards 2400 aortic valve prosthesis with those produced
by the same valve but having a simulated overgrowth at the apex of the struts. Comparisons were made over the entire cardiac
cycle for time and amplitude, power-density spectra, power-distribution spectra, power-distribution surfaces associated with
individual valves, and three-dimensional power-distribution-difference surface. Power-density spectra were compared for portions
of the cycle corresponding to the opening, systolic, and closing sounds of the valve. Physical parameters of an acoustical
model were estimated from the power-density spectra. The results showed that each comparison gave information pertinent to
the simulated malfunction. Opening. systolic and closing sounds, respectively, were different for each valve. The opening
sound of the abnormal valve displayed a much lower frequency. Systolic sounds for the two valves were similar in frequency,
but the normal valve produced more total power for this sound. The closing sound of the abnormal valve occurred later than
that of the normal valve. These differences were more clearly seen when viewed in the frequency domain. 相似文献
10.
Zhang JS Kaltenbach JA Wang J Kim SA 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,153(4):655-660
Fos-like immunoreactivity (FLI) was evaluated in auditory and nonauditory brain structures in hamsters that had been exposed previously to intense sound and tested behaviorally for tinnitus. The immunocytochemical results demonstrated a significant increase in exposed animals of FLI in auditory brain structures such as the lateral lemniscus, central nucleus of inferior colliculus, and auditory cortex, as well as in some nonauditory brain structures such as the locus coeruleus, lateral parabrachial nucleus, certain subregions of the hypothalamus, and amygdala. The behavioral scores suggest that animals that had been exposed to intense sound developed tinnitus. This is consistent with the hypothesis that FLI induced by intense sound exposure might represent a neural correlate of tinnitus or of plasticity associated with tinnitus. The possibility and the mechanisms underlying the increased FLI are discussed. 相似文献