Hearing Aid Styles: Hearing aids come in a wide range of sizes and styles, including completely in the canal (CIC), in the canal (ITC), in the ear (ITE) or behind the ear (BTE). There are two new types of hearing aids: Open-fitting and the deep Post-auricular-Canal (PAC). The Open fitting is used for patients who have normal or near normal hearing in low frequencies with complaint of hearing echo and their own voice. The type of hearing aid recommended depends on your individual needs. Hearing Aid Technology: Today's technology provides significant advances over older conventional hearing aids. With the invention of modern computer software, we now have a vast selection of programmable hearing aids using digital processing and directional microphones for better hearing in many listening situations. CONVENTIONAL HEARING AIDS may have linear or compression circuits. Linear Circuit: A linear circuit is one that is simply an amplifier, it makes EVERYTHING louder. This type of circuit is the least sophisticated and gives no means to filter out unwanted background noise. Compression Circuit: A compression circuit also turns everything up, but with less distortion because of the way it processes sound. This type of circuit is also better able to accommodate a patient's range of hearing. Basically, the circuit always makes the sound loud enough for the patient to hear, but never gets louder than a level beyond what a patient can tolerate. A PROGRAMMABLE circuit is much more sophisticated than the linear and basic compression circuits. The circuit can adjust the overall volume based on the loudness of sounds coming into the hearing instrument. The softer the sound, the more will be the amplification of the hearing aid. Some programmable circuits have two or three channels for higher fine tuning ability to match the patient's hearing loss and to give the patient a clearer speech signal. DIGITAL : This circuit has a superior fine tuning ability to match the patient's hearing loss and filter out sounds that it identifies as background noise. Digital hearing aids analyze the sounds around you and adjust the signal based on that analysis. Some hearing aids divide complex sounds into 15 different segments and process the sounds completely separately. There are very advanced technologies available in digital hearing aids to minimize feedback (unwanted whistle most Hearing aids emit when one opens his/her mouth). Some hearing aids are able to communicate with each other and others are able to log all the environments that patients wear the hearing aids and all the adjustment that patient made to the hearing aids. DIRECTIONAL HEARING AIDS: A DEFINITE IMPROVEMENT Directional technology utilizes dual microphones and is available in programmable or digital models. It can function in omnidirectional mode (using just one microphone) or in the directional mode (using both microphones). This directional mode would be utilized in a noisy restaurant, for example, to help you focus in on what the person or people you are with are saying, while dampening the chatter around you. Recently, many articles have confirmed the efficacy of this technology both in the BTE , ITE, and Half Shell hearing aids. The newer versions of the directional microphones are adaptive. These microphones can discern where the unwanted sound is coming from and thereby adjust directionality accordingly to maximize understanding.