At times, medical knowledge moves forward in leaps and bounds. At other times such knowledge moves forward in a more gradual fashion. Such has been the case with our knowledge of the effects of hearing loss on the brain.
Seven years ago, Dr. Frank Lin of Johns Hopkins Medical University reported that hearing loss was highly associated with dementia and accelerated brain shrinkage. At that time, our medical knowledge on this topic took a giant step forward.
Since that report, our understanding of this relationship has been more evolutionary. For example, Drs. Glick and Sharma showed that untreated and poorly treated hearing loss results in a scrambling of brain resources.
These researchers showed improperly treated hearing loss results in inappropriate use of the frontal and prefrontal areas of the brain. Typically, these two areas of the brain are associated with memory and reasoning. However, in the case of poorly treated hearing loss, these two brain areas are used for understanding speech, lending credence to Dr. Lin’s hypothesis that hearing loss may overwork the memory and reasoning areas of the brain.
On a positive note, Glick and Sharma showed that properly fit hearing aids may reset the brain so that the auditory area is once again used for listening. Now the frontal and prefrontal brain areas can resume their normal functions.
More recently, it was discovered that hearing loss upsets the normal rhythmic pulses and interconnections the brain uses to communicate among its different functional areas.
Within the last few months, two separate reports out of Boston and Northwestern Universities showed reestablishing appropriate pulse rates among these different areas of the brain results in significant memory improvements in older people.
These studies, when considered together, suggest the possibility that properly treated hearing loss with hearing aids, perhaps combined with brain pulse resetting, may combat the devastating effects hearing loss may have on memory.
Currently, several large-scale studies are under way, examining the potential therapeutic benefit of properly fit hearing aids and brain pulse resetting on memory. In the interim, it appears medically prudent to treat hearing loss sooner rather than later, as the average delay between diagnosis of hearing loss and treatment has recently been reported to be nine years. It is no longer appropriate to view hearing loss as an inconvenience that can be ignored.
At our clinic, we are currently reviewing the records of 51 patients who have normal aided scores on the same speech in noise test shown by Glick and Sharma to signal brain resource preservation in hopes of identifying those therapeutic steps that can properly reset the brain.
Those interested in obtaining further information on this topic are invited to the monthly meeting of the Oregon Association for Better Hearing at Corvallis Good Samaritan Hospital, Conference Room B on the second Thursday of every month from 3:30 to 5:00 p.m.