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IntroductionIndividuals with the same ability of speech recognition in quiet can have extremely different results in noisy environments.ObjectiveTo standardize speech perception in adults with normal hearing in the free field using the Brazilian Hearing in Noise Test.MethodsContemporary, cross-sectional cohort study. 79 adults with normal hearing and without cognitive impairment participated in the study. Lists of Hearing in Noise Test sentences were randomly in quiet, noise front, noise right, and noise left.ResultsThere were no significant differences between right and left ears at all frequencies tested (paired t  1 test). Nor were significant differences observed when comparing gender and interaction between these conditions. A difference was observed among the free field positions tested, except in the situations of noise right and noise left.ConclusionResults of speech perception in adults with normal hearing in the free field during different listening situations in noise indicated poorer performance during the condition with noise and speech in front, i.e., 0°/0°. The values found in the standardization of the Hearing in Noise Test free field can be used as a reference in the development of protocols for tests of speech perception in noise, and for monitoring individuals with hearing impairment.  相似文献   
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In this paper, we investigate the claim that although the same lexical units are involved in speech production and comprehension, there are separate input and output phoneme layers (Foygel and Dell, 2000). Data from a case series of aphasic patients are used to test this claim by examining the relationship between performance on a test of picture naming and performance on tests of phonological input. Estimates of each patient's semantic-lexical and phonological impairments in speech production were derived from Foygel and Dell's computational model of picture naming. It was found that the strength of the semantic-lexical impairments in speech production was significantly correlated with performance on auditory comprehension tests. This finding is consistent with the claim that the same lexical units are involved in speech comprehension and production. Conversely, the correlations between the strength of the phonological lesions in speech production and performance on tests of phonological input were non-significant, consistent with Foygel and Dell's claim that there are distinct input and output phoneme layers.  相似文献   
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Summary This paper deals with a particular aspect of speech motor control in patients suffering from apraxia of speech. Three experiments are reported concerning the phase relations between individual speech gestures. These include the timing of laryngeal, velar and labial movements relative to lingual gestures.A total of 8 patients and 12 normal controls were examined using speech material which was designed according to appropriate phonetic paradigms. Evaluation was performed on the basis of speech signal parameters referring to the kinematics of inter-articulatory phasing. Deviations of the patient group were found in all three experiments. This suggests that disturbed phase relations of individual speech movements are a general feature of apraxic speech. It is further hypothesized that the described motor symptoms are the origin of a variety of phonemic errors. Support for this view is provided by appropriate examples which refer to the examined paradigms. By this argument, much of the disturbed phonemic structure of apraxic speech may be accounted for by timing deficits.  相似文献   
5.
An image processing system for application to studies of the temporal and spatial parameters of movement during swallowing and speech is described. Image sequences from videotape are digitized for computerized manipulation and analysis in an attempt to improve on conventional visual inspection. The system is “interactive” or “event-driven”: after executing a function, the computer waits for guidance from the user who controls the program through keyboard and mouse input, selecting options from menus and responding to prompts. The analyst alters image clarity by the application of filters and heightens contrast through video enhancement. A technique called “remapping” reduces head motion and provides uniform spatial scaling. Animated sequences of images are used, as opposed to frame-by-frame analysis, to preserve temporal context and increase efficiency of measurement. Low cost off-the-shelf personal computer hardware is used along with original software tailored to the application.  相似文献   
6.
A microprocessor-based real-time digital vibrotactile vocoder system has been developed to train the deaf and for artificial hearing research. The system is composed of a microcomputer module with a digital signal processor interface units and an attenuator/driver circuit. Live or digitised (stored or synthetic) speech is presented to the skin spectrally through a belt housing eight or 16 vibrators. Speech is processed in real time using a fast Fourier transform. The system is also capable of presenting any arbitrary spatiotemporal pattern on the skin for artificial hearing experiments. A preliminary experiment with a deaf subject indicates that the system is potentially an effective device for artificial hearing.  相似文献   
7.
F. Loew 《Acta neurochirurgica》1992,118(1-2):80-83
Summary Man is distinguished and differentiated from other living creatures by possessing less genetically determined characteristics, behaviour and reactions, with fewer features fitting him for a special environment. For this reason he enjoys greater freedom and adaptability.In order to be able to pass on the necessarry lessons for survival, man must have command of his speech, and as a species can only exist within communities. This presupposes an instinctive drive to make rules and regulations for ordered living in society.Speech is not only a means of communication but also the basis and precondition of abstract thinking. Complete aphasia implies the loss of this ability. It would deprive man from the most important of his key functions. Therefore it is inhuman.These reflections have convinced me absolutely, that neurosurgical interventions, which would have the predictable result of total aphasia, must not be performed, even though prolongation of life, but without speech, might thus be bought.  相似文献   
8.
全喉切除改良气管-咽吻合Ⅰ期发声重建术   总被引:1,自引:1,他引:0  
目的:探讨全喉切除Ⅰ期发声重建术的改进术式。方法:采用低位气管切开,全喉切除,食管前壁黏膜重建声门,气管切口处造瘘.颈段气管上提并缩窄吻合于舌根的方法行全喉切除及Ⅰ期发声重建木35例。结果:33例(94.29%)术后获得了不同程度的发声功能.不能发声者仅2例(5.71%)。全部患者术后均可经口进食,未出现严重的影响生存质量的误咽。结论:与以往的发声重建术相比,本术式具有发声成功率高、发声质量良好、误咽率低等优点,且无须置人人工发声装置.值得推广。  相似文献   
9.
Summary: Purpose : As shown previously, when temporal lobe complex partial seizures (TLCPS) originate from the language dominant hemisphere, patients cannot read a test phrase correctly within 60 s of the end of the ictal discharge. We wished to assess whether postictal language testing results discordant with this pattern identified patients with non-left (right hemisphere or mixed) language dominance.
Methods : Since 1988, all patients undergoing video/EEG monitoring at our institution have been given a test phrase to read aloud as soon as a seizure is detected. Inclusion criteria for this study were (a) postictal language testing within 60 s of seizure end for at least one TLCPS, (b) >90% seizure reduction after anterior temporal lobectomy with 2-year minimum follow- follow- up, and (c) language localization by either intracarotid amobarbital test (IAT) or direct electrical stimulation of left hemisphere cortex.
Results : Two hundred twenty-four seizures in 64 patients were analyzed. Discordant postictal language patterns were noted in 10 of 11 patients with IAT documented non-left language dominance and in 15 of 53 with left dominance (p = 0.006; sensitivity 90.9%, specificity 71.7%).
Conclusions : Postictal language testing accurately identifies patients with non-left language dominance and may be useful in selecting appropriate patients for IAT.  相似文献   
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