الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 79 |  |  |
| | | from | 79 | | |
Abstract
Physiological aging is commonly associated with a general decline of cognitive skills, including language skills, memory, the speed of information processing and attention. These reductions in cognitive performance probably reflect age-related changes in the brain, which involve several structural and functional changes during aging and these changes associated with aging brain can be detected in neurologically asymptomatic aged people.
In the present study the process of cognitive aging was investigated by analyzing P300 which can be generated by various stimulus modalities and MMN potentials, which reflects automatic stimulus-change detection in the central auditory system.
The goal of this study was to assess the effect of aging on auditory event related potentials. The study was carried out on 45 subjects attended the audiology unit at Alexandria Main University Hospital. These subjects divided into 3 groups. The first group was 15 young adults (below 40 years) with bilateral normal hearing, the second group was 15 elderly subjects (above 60 years) with no hearing handicap (according to HHIE score) and with bilateral mild hearing loss and the third group was 15 elderly subjects (above 60 years) with some degree of hearing handicap (according to HHIE score) and with bilateral moderate hearing loss.
All subjects of the study group were subjected to the following protocol:
1- Complete history taking.
2- Complete otological examination.
3- Basic audiological evaluation including:
- Pure tone audiometry: measurement of air and bone conduction thresholds in the conventional frequency range.
- Immitancemetry including tympanometry and acoustic reflexes thresholds.
4- Assessment of hearing handicap using HHIE in the standard sheet (appendix 1).
It was translated into arabic to each subject during assessment.
Subjects were divided according to the results of HHIE into:
- 15 subjects had no handicap.
- 15 subjects had handicap (12 of them had mild to moderate handicap and 3 had sever handicap).
5- Electrophysiological central auditory tests that includedERPs: P300 (active condition) and MMN (distracted condition) were recorded in response to an auditory oddball paradigm.
Subjects were selected according to the following criteria:
1- Neurologically free.
2- No gender limitation.
3- No major complaint about hearing.
4- No previous otological disorders or operations.