Auditory Fatigue: Loss of sensitivity to sounds as a result of auditory stimulation, manifesting as a temporary shift in auditory threshold. The temporary threshold shift, TTS, is expressed in decibels.Sensory Thresholds: The minimum amount of stimulus energy necessary to elicit a sensory response.Hearing Loss, Noise-Induced: Hearing loss due to exposure to explosive loud noise or chronic exposure to sound level greater than 85 dB. The hearing loss is often in the frequency range 4000-6000 hertz.Auditory Threshold: The audibility limit of discriminating sound intensity and pitch.Fatigue: The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.MP3-Player: Portable electronics device for storing and playing audio and or media files. MP3 for MPEG-1 audio layer 3, is a digital coding format.Noise: Any sound which is unwanted or interferes with HEARING other sounds.Embolism, Air: Blocking of a blood vessel by air bubbles that enter the circulatory system, usually after TRAUMA; surgical procedures, or changes in atmospheric pressure.Diving: An activity in which the organism plunges into water. It includes scuba and bell diving. Diving as natural behavior of animals goes here, as well as diving in decompression experiments with humans or animals.Barotrauma: Injury following pressure changes; includes injury to the eustachian tube, ear drum, lung and stomach.Decompression Sickness: A condition occurring as a result of exposure to a rapid fall in ambient pressure. Gases, nitrogen in particular, come out of solution and form bubbles in body fluid and blood. These gas bubbles accumulate in joint spaces and the peripheral circulation impairing tissue oxygenation causing disorientation, severe pain, and potentially death.Decompression: Decompression external to the body, most often the slow lessening of external pressure on the whole body (especially in caisson workers, deep sea divers, and persons who ascend to great heights) to prevent DECOMPRESSION SICKNESS. It includes also sudden accidental decompression, but not surgical (local) decompression or decompression applied through body openings.Gases: The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)Pulmonary Embolism: Blocking of the PULMONARY ARTERY or one of its branches by an EMBOLUS.Hearing Loss: A general term for the complete or partial loss of the ability to hear from one or both ears.Hearing Loss, Sensorineural: Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.Health Literacy: Degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions.Hearing: The ability or act of sensing and transducing ACOUSTIC STIMULATION to the CENTRAL NERVOUS SYSTEM. It is also called audition.Hearing Tests: Part of an ear examination that measures the ability of sound to reach the brain.Hearing Disorders: Conditions that impair the transmission of auditory impulses and information from the level of the ear to the temporal cortices, including the sensorineural pathways.Comprehension: The act or fact of grasping the meaning, nature, or importance of; understanding. (American Heritage Dictionary, 4th ed) Includes understanding by a patient or research subject of information disclosed orally or in writing.Fatigue Syndrome, Chronic: A syndrome characterized by persistent or recurrent fatigue, diffuse musculoskeletal pain, sleep disturbances, and subjective cognitive impairment of 6 months duration or longer. Symptoms are not caused by ongoing exertion; are not relieved by rest; and result in a substantial reduction of previous levels of occupational, educational, social, or personal activities. Minor alterations of immune, neuroendocrine, and autonomic function may be associated with this syndrome. There is also considerable overlap between this condition and FIBROMYALGIA. (From Semin Neurol 1998;18(2):237-42; Ann Intern Med 1994 Dec 15;121(12): 953-9)Pleurodynia, Epidemic: An acute, febrile, infectious disease generally occurring in epidemics. It is usually caused by coxsackieviruses B and sometimes by coxsackieviruses A; echoviruses; or other enteroviruses.Encephalomyelitis: A general term indicating inflammation of the BRAIN and SPINAL CORD, often used to indicate an infectious process, but also applicable to a variety of autoimmune and toxic-metabolic conditions. There is significant overlap regarding the usage of this term and ENCEPHALITIS in the literature.Evidence-Based Medicine: An approach of practicing medicine with the goal to improve and evaluate patient care. It requires the judicious integration of best research evidence with the patient's values to make decisions about medical care. This method is to help physicians make proper diagnosis, devise best testing plan, choose best treatment and methods of disease prevention, as well as develop guidelines for large groups of patients with the same disease. (from JAMA 296 (9), 2006)Encephalomyelitis, Autoimmune, Experimental: An experimental animal model for central nervous system demyelinating disease. Inoculation with a white matter emulsion combined with FREUND'S ADJUVANT, myelin basic protein, or purified central myelin triggers a T cell-mediated immune response directed towards central myelin. The pathologic features are similar to MULTIPLE SCLEROSIS, including perivascular and periventricular foci of inflammation and demyelination. Subpial demyelination underlying meningeal infiltrations also occurs, which is also a feature of ENCEPHALOMYELITIS, ACUTE DISSEMINATED. Passive immunization with T-cells from an afflicted animal to a normal animal also induces this condition. (From Immunol Res 1998;17(1-2):217-27; Raine CS, Textbook of Neuropathology, 2nd ed, p604-5)Xenotropic murine leukemia virus-related virus: An endogenous GAMMARETROVIRUS from the germ line of mice but isolated from humans. It has close similarity to xenotropic MURINE LEUKEMIA VIRUS.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Reflex, Acoustic: Intra-aural contraction of tensor tympani and stapedius in response to sound.Sound: A type of non-ionizing radiation in which energy is transmitted through solid, liquid, or gas as compression waves. Sound (acoustic or sonic) radiation with frequencies above the audible range is classified as ultrasonic. Sound radiation below the audible range is classified as infrasonic.Ear Canal: The narrow passage way that conducts the sound collected by the EAR AURICLE to the TYMPANIC MEMBRANE.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.Oscillometry: The measurement of frequency or oscillation changes.TennesseeEvent-Related Potentials, P300: A late-appearing component of the event-related potential. P300 stands for a positive deflection in the event-related voltage potential at 300 millisecond poststimulus. Its amplitude increases with unpredictable, unlikely, or highly significant stimuli and thereby constitutes an index of mental activity. (From Campbell, Psychiatric Dictionary, 6th ed)Evoked Potentials, Auditory: The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.Electroencephalography: Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.Evoked Potentials: Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.Acoustic Stimulation: Use of sound to elicit a response in the nervous system.Reaction Time: The time from the onset of a stimulus until a response is observed.DNA Contamination: The presence of DNA from a source foreign to the sample being analysed.Retroviridae Infections: Virus diseases caused by the RETROVIRIDAE.Psychology, Clinical: The branch of psychology concerned with psychological methods of recognizing and treating behavior disorders.Gammaretrovirus: A genus of RETROVIRIDAE comprising endogenous sequences in mammals, related RETICULOENDOTHELIOSIS VIRUSES, AVIAN, and a reptilian virus. Many species contain oncogenes and cause leukemias and sarcomas.Child Psychology: The study of normal and abnormal behavior of children.American Speech-Language-Hearing Association: A professional society concerned with the diagnosis, prevention, treatment, and remediation of speech, language, and hearing disorders.Perceptual Disorders: Cognitive disorders characterized by an impaired ability to perceive the nature of objects or concepts through use of the sense organs. These include spatial neglect syndromes, where an individual does not attend to visual, auditory, or sensory stimuli presented from one side of the body.Auditory Perception: The process whereby auditory stimuli are selected, organized, and interpreted by the organism.Language Disorders: Conditions characterized by deficiencies of comprehension or expression of written and spoken forms of language. These include acquired and developmental disorders.Learning Disorders: Conditions characterized by a significant discrepancy between an individual's perceived level of intellect and their ability to acquire new language and other cognitive skills. These disorders may result from organic or psychological conditions. Relatively common subtypes include DYSLEXIA, DYSCALCULIA, and DYSGRAPHIA.

Noise exposure and hearing loss among student employees working in university entertainment venues. (1/12)

OBJECTIVES: Most studies to date on sound levels in entertainment establishments have concentrated on exposure levels for the attending public, rather than employees who may be at greater risk of hearing loss. Of particular concern are young employees. The aim of this pilot study was to (i) estimate typical sound levels in different areas where amplified music was played, (ii) measure temporary threshold shift (TTS) and (iii) estimate the dependence of hearing threshold shifts on measured noise levels. METHODS: This study focused on students working part-time (up to 16 h/week) in music bars and discotheques in a university entertainment venue. All 28 staff were invited to participate in the study. Pre- and post-exposure audiometry was used to determine hearing threshold at both high and low frequencies. Personal dosemeters and static measurements were made to assess noise levels and frequency characteristics. A questionnaire was used to determine patterns of noise exposure and attitudes to noise levels and hearing loss. RESULTS: Of the 28 student employees working in the three areas, 14 (50%) agreed to take part in the study, giving 21 pre- and post-shift audiograms. The mean personal exposure levels for security staff were higher than those of bar staff, with both groups exceeding 90 dB(A). The maximum peak pressure reading for security staff was 124 dB. Although TTS values were moderate, they were found to be highly significant at both low and high frequencies and for both ears. Twenty-nine per cent of subjects showed permanent hearing loss of more than 30 dB at either low or high frequencies. The correlation between TTS and personal exposure was higher at 4 kHz than the low and high frequencies. CONCLUSIONS: Contemporary music may be an important yet little considered contributor to total personal noise exposure, especially amongst young employees. Employees need to be better informed of risks of hearing loss and the need to report changes in hearing acuity. Suggestions are made on strategies for improving the assessment of noise exposure in entertainment venues.  (+info)

Evaluation of auditory fatigue in combined noise, heat and workload exposure. (2/12)

This study was performed in a climatic chamber to evaluate the combined effects of noise intensity, heat stress, workload, and exposure duration on both noise-induced temporary threshold shift (TTS) and the recovery time by adopting Taguch's method. Fourteen subjects without previous significant noise exposure and smoking history were recruited to participate in this study. All hearing threshold levels at eight different frequencies (250 to 8,000 Hz) of better ear were measured in an audiometric booth by using the ascending method in 2 dB steps before each exposure condition. The test was also carried out after exposure to evaluate TTS at various times. The TTS recovery time was assessed using an audiometric test on all subjects at post-exposure times of 2, 20, 40, 60, 80 and 120 min, respectively. It was found that TTS depended mainly on the exposed noise dose and was enhanced by workload and heat stress. The TTS recovery time is dependent upon the magnitude of the initial hearing loss. In conclusion, TTS driven by noise exposure is enhanced by heat and workload. Further studies are required to evaluate the effects of workload with extreme temperature in a workplace environment.  (+info)

The efficiency of otoacoustic emissions and pure-tone audiometry in the detection of temporary auditory changes after exposure to high sound pressure levels. (3/12)

Exposure to noise has a harmful effect on the auditory health of workers. AIM: The main goal of this paper was to establish the role of pure-tone audiometry and evoked transient otoacoustic emissions in the detection of small temporary auditory changes after exposure to high sound pressure levels. STUDY DESIGN: A cross-sectional cohort study. MATERIAL AND METHODS: 30 otologically normal subjects aged between 20 and 35 years were submitted to pure-tone audiometry and evoked transiente otoacoustic emissions before and after 5 hours of exposure to high sound pressure levels (between 80 and 90 dB). RESULTS: For pure-tone audiometry the largest changes occurred at high frequencies--from 3 KHz to 8 KHz after exposure. The evoked transient otoacoustic emissions showed reduced reproductibility from 1 KHz to 4 KHz after exposure to noise. CONCLUSION: We noted that both pure-tone audiometry and evoked transient otoacoustic emissions had a role in detecting statistically significant changes in the auditory threshold and in reproductibility, after exposure to high sound pressure levels.  (+info)

Temporary threshold shifts at 1500 and 2000 Hz induced by loud voice signals communicated through earphones in the pinball industry. (4/12)


Preferred sound levels of portable music players and listening habits among adults: a field study. (5/12)


Prevalence of noise-induced hearing-threshold shifts and hearing loss among US youths. (6/12)


Long-term, but not transient, threshold shifts alter the morphology and increase the excitability of cortical pyramidal neurons. (7/12)


Digital music exposure reliably induces temporary threshold shift in normal-hearing human subjects. (8/12)


  • METHODS Functional magnetic resonance imaging (fMRI) was used to assess brain activation during a working memory task (a modified version of the paced auditory serial addition test) in nine patients with TBI and seven healthy controls. (
  • Endophilin-A regulates presynaptic Ca 2+ influx and synaptic vesicle recycling in auditory hair cells. (
  • A method and system for improving auditory processing and increasing spatial awareness, wherein the voices of a musical composition are arranged, recorded and produced in particular combinations and at particular frequency levels according to a predetermined program designed to exercise auditory muscles, imprint the frequency map, and stimulate dendritic growth and synaptic organization. (
  • B. L. Lonsbury-Martin, and M. B. Meikle, Neural correlates of auditory fatigue: frequency-dependent changes in activity of single cochlear nerve fibers, J. Neurophysiology , 41:987 (1978). (
  • Assistive listening devices can improve the neural representation of speech and impact reading-related skills by enhancing acoustic clarity and attention, reducing variability in auditory processing. (
  • Jet lag is a temporary condition caused by rapid travel across time zones -- as may occur with jet trips -- and may leave an individual experiencing fatigue, insomnia , nausea, or other symptoms as a result of the internal circadian rhythm , or body clock, being misaligned with local time. (
  • This is a phase IV observational, non-interventional, prospective, multicentric study to evaluate cognition in RRMS subjects treated with Rebif and its relationship to the fatigue and neurological dysfunction status. (
  • 5. A developmental or neuropsychological assessment might be necessary if auditory processing is considered to be the issue and is not secondary to fatigue or lethargy. (
  • Performance was affected by fatigue in both a head-injured and matched population, which has implications for health care professionals involved in rehabilitation and assessment. (
  • Studies in adults demonstrate the effectiveness of RMHAs in mitigating hearing difficulties in conditions which are known to cause central auditory temporal distortions (multiple sclerosis, Friederich Ataxia)(Lewis et al. (
  • Fatigue is the most common symptom in people with multiple sclerosis (MS). Poor sleep also occurs in this population. (
  • MS-related fatigue, "the subjective lack of physical and/or mental energy that is perceived by the individual or caregiver to interfere with usual and desired activities" [ 1 ], is one of the most common symptoms in people with multiple sclerosis (MS), affecting up to 92% of individuals with the disease [ 2 , 3 ]. (
  • Anecdotal evidence does suggest that presentation of low-frequency binaural auditory beats can elicit a variety of changes in the listener's state of consciousness that might have a broad range of practical applications (5,7). (
  • For example, the presentation of binaural auditory beats in the delta and theta frequency ranges is said to be associated with enhanced creativity and improved sleep. (
  • Preliminary experimental studies suggest that binaural auditory beats in the EEG beta frequency range can enhance attention and memory task performance (3), and that those in the alpha frequency range may increase alpha EEG production and subjective relaxation (2). (
  • A recent study examined the effects of delta and theta frequency binaural auditory beats on EEG spectral patterns in healthy volunteers. (
  • Taken together, the anecdotal, clinical, and preliminary experimental evidence suggests that the presentation of binaural auditory beats may produce controllable changes in EEG and/or subjective states of consciousness. (
  • As MMN reductions only emerged in patients with a longer course of illness, and appeared to change with symptom severity, this suggests a dynamic change in the early auditory processing of language over time in schizophrenia. (
  • A fascinating study led by King's College in London has shown success in rapidly reducing auditory hallucinations in people with schizophrenia. (
  • These effects are more intense when cocaine usage is stopped and can include other effects such as fatigue , listlessness, anxiety, irritability, sleepiness and paranoia. (
  • Language Processing: Uses the language information in the mind of listener, not the auditory signal. (
  • Mismatch negativity (MMN) is a measure of pre-attentive auditory information processing related to change detection. (
  • The ability to encode the speech signal is determined by ascending and descending auditory processing. (
  • Speech-Processing Fatigue in Children: Auditory Event-Related Potential and Behavioral Measures Purpose Fatigue related to speech processing is an understudied area that may have significant negative effects, especially in children who spend the majority of their school days listening to classroom instruction. (
  • Purpose Fatigue related to speech processing is an understudied area that may have significant negative effects, especially in children who spend the majority of their school days listening to classroom instruction. (
  • One of the most exciting research findings in the treatment of auditory processing disorder (APD) is the neuroplastic benefit of amplification. (
  • That would have helped determine whether the patterns in a subject's auditory processing were different than normal. (
  • In the scale illusion, healthy listeners obtain the illusion of distinct melodies, which are the result of grouping of information from both ears into illusory auditory streams. (
  • Ears and auditory concentration both fatigue quickly, so testing must be done when a listener is fresh. (