Auditory and Vestibular Research
Volume:10 Issue: 2, 2000

Infants hearing screening as one of the best methods of identification and hence early intervention to prevent side effects and appropriate rehabilitation if necessary.Methods and Materials: 175 0-7 day infants were tested in two groups (112 normal history and 63 high risked) with a dumb (for low frequencies)and receiver (for high Frequencies) at 90-95 dB SPL in three hospitals. The acceptable responses were auropalpebral reflex (APR), startle and stop of movements. Of the first group 51% showed APR, 10% startle, 22 % Both and 17% no response. Of the second group 47% showed APR, 24% startle, 11% both reflexes and 18% no response. 14 cases (8 girls and 6 boys) out of 175 infnats showed no response.

OAEs are sound founds in the external aditory meatus that originate in the cochlea. OAEs are generated only when the organ of corti is in near normal condition and They can be detected only when the middle ear system is operating normally. The sound generated by the cochlea are small but potentially audible, sometimes as much as 30 dBSPL. They can emerge spontaneously in the cochlea, but more commonly OAEs follow acoustic stimulation. No electrod are needed to observe OAEs. In fact, microphone are used to detect them.

In addition to Stimulus frequuncy and level, emitting Inner ear structurs status, OAEs parameters depend on conductive sound pathways charactristics, so abnormal OAEs donot always represent cochlear abnormality. Middle ear transmites Vibrations in two directions: forward and backward. Middle ear pathologies affect both forward and backward transmission.In this paper, The purpose is investigation of immediate effects of tympanic over - and under - pressure on click evoked Otoacoustic Emissions (CEOAEs) in healthy individuals. Healthy subjects with normal hearing and middle ear were exposed to ambient pressure changes in a pressure champer. The pressure was progressively changed in 100 dapa steps to accomplish on increase and decrease in tympanic pressure. Pressure equilibration of the middle ear was avoided. The relative tympanic over-and under - pressure (+/-320 dapa) was monitored by tympanometry and CEOAEs recorded at every step of tympanic pressure change. The CEOAEs recorded during progressive tympanic over-and under- pressure had reduced amplitude and shorter latencies that were most pronounced in the 750 to 3000 Hz frequency bands.

In order to develop oral communication, hearing impaired infants and young children must be able to hear speech comfortably and consistently. To day children with all degrees of hearing loss may be condidates for some kinds of amlification.As children differ from adults, many Factors should be consider in hearing aid selection, evaluation and fitting. For example the child age when he or she is candidate for custom instruments? Do we consider programmable Hearing aid? Are multi memory instruments appropriate for them? What about directional microphones? What style of hearing aid do we select? In this paper such questions are responded.

One of the most important issue for selecting and fitting of hearing aids that should receive special attention is binaural amplification.According to several investigations, superiority of binaural amplification on monaural one is confirmed.Binaural Amplification may have considerable effects on fromation and developing of superior dimensions of hearing including: Localization, Binaural squelch (Better hearing in presence of noise).So, it is necessary to know the basic and scientific concepts and applicable principles of binaural hearing and binaural fitting.Present paper deals with this important subject.

Auditory integration training (AIT) is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depressin, and hyperacute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of The Sound of a Moracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.