ILE Hearing Aids| Questions and Answers with complete solution

Hand Cupped Behind Ear - -first Hearing Aid -increased sound by 5-8db -included horns,trumpets, speaking tubes 1892 - -carbon amplifiers patent by Alexander Bell -marketed until 1930;first patent for a telephone type hearing instrument 1920 - large vacuum tubes; not portable 1938 - miniature vacuum tube ;crystal receivers 1930 - diameter reduced 1940 - bone conduction receivers were introduced 1946 - first telecoil introduced 1950 - bodyworn HA became convenient size 1948 - transistor invented 1954 - eyeglasses aids introduced 1974 - microphones electrets were introduced 1964 - intergrated circuit(transistors, resistors, wiring...)1952 - first transistors The Most Important function of the oval window is to : - transfer vibration from the ossicular chain Hair Cells a rise from the layer on top of the : - organ of corti The theory of hearing that is considered the most accurate is : - Place Theory, Volley Theory, Temporal Theory The Three semicircular canals are: - 1)90degress angle to one another 2)superior,posterior, and lateral 3)detectors of rotational movement in any direction The average length of an uncoiled basilar membrane is - 35mm The name given to the nerve cells connecting the organ of corti to the 8th cranial Nerve is : - Spiral Ganglia The Theory of hearing that describes the cochlea as consisting of nerve ending with hair cells that respond to specific frequencies: - The Place Theory The basilar membrane is located: - In the scala media Sounds appear to be louder when both ears hear together because of: - binaural summation Collectively the semi circular canals are called the - vestibular system The inability of the brain to accurately process auditory stimuli is called a - Central Hearing