Have you noticed how few people wear monocles these days? People wear two lenses in their spectacles because they have two eyes. Usually those eyes have a similar degree of eyesight loss. But what of our ears?

• 360 degree hearing – it may be stating the obvious, but if we only had one ear we’d find it difficult to hear sounds that happened on the opposite side to our ear. That’s partly because of the way our ears catch sound and funnel it in and partly because our head actually damps down sound coming from the other side. With two ears we can hear what’s happening all around us, with a slight bias to sounds that happen in front of us (due to the shape of our ears and how our brains interpret the sound).
• Improved hearing – using two ears rather than one can actually increase the loudness of a sound by up to 6-10db. It can also improve speech recognition by up to 20%.
• Directional hearing – our brains use the signals coming in from each ear to locate the origin of a sound. If the sound occurs on our right hand side, the noise will reach our right ear quicker than the left ear, and although the time difference is miniscule our brain can detect it. Also the sound will be slightly quieter on the left hand side because the sound will have been damped down by hitting our head first.
• Easier to Hear in Background Noise – our brains combine the signal from both ears to emphasise speech when there's a lot of background noise. It is especially effective in situations such as group conversation in a noisy room (e.g. restaurant). In fact, the speech we're trying to hear can actually be quieter than the background noise and we'll still understand most of what was said if our hearing is normal.

Most hearing losses occur almost equally in both ears, so if your right ear is bad then your left ear will be similarly bad. There are exceptions to this, and a hearing test will show up the difference between the two ears.

If your hearing loss is similar in both ears then it is usually best to wear two hearing instruments.

Eight reasons to wear two hearing instruments

• To balance you up
• So you can hear things equally well no matter which ear someone speaks to you on
• To give you extra volume without it sounding 'too loud'
• To ensure you hear as well as you can in background noise
• To help your understanding of speech
• To decrease fatigue
• To help locate where sounds are coming from
• So you have a spare aid if one goes wrong

Research has also shown that Speech Recognition (i.e. how the brain recognises and understands speech) deteriorates rapidly in the unaided ear but remains good in the aided ear. If a user finally decides to wear two hearing instruments after this deterioration has occurred they find the previously unaided ear still has more difficultly understanding speech.

So if you do need two hearing instruments and you can afford two it’s best to have them. It’s the best way to preserve and improve the hearing you have.

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