History and future of hearing aids

The hearing aid has performed a vital function for those suffering from hearing loss for nearly two centuries, but like any other electrical technology, they have developed rapidly with the introduction of the microprocessor in the latter part of the 20th century. Hear today... But what tomorrow? From the ear horn to stem cell research, we take a look back at the history of the hearing aid to see how these devices have evolved over the years... 1800s The earliest hearing aids Essentially nothing more than horn-style devices designed to capture more sound and direct it into the ear canal - first became popular in the 1800s. 1890s The first electric hearing aid In 1898, the first electric hearing aid was created by Miller Reese Hutchison. A portable carbon transmitter was used to amplify weak signals using an electric current, based on the principle used in the telephone. Wearable and practical instruments were available from 1902, but were not in popular use until the 1940s. Even then, they only had the power to correct moderate hearing loss. Carbon Microphone DIAPHRAGM (FLEXIBLE ELECTRODE) SOUND WAVES SIGNAL ---> CARBON GRANULES FIXED ELECTRODE VOLTAGE SOURCE (BATTERY) 1920s Hot and heavy Naval engineers patented the first vacuum-tube hearing aid in 1920, naming it the Vactuphone. This device used a telephone transmitter to convert sound into electrical signals, which were then amplified once they reached the receiver. The Vactuphone had more power than carbon aids and was portable, but required two batteries at a time when they were expensive. 1950s Race to the new style EAR HOOK 1950 Bell Laboratories CONNECTING TUBE The first transistors were developed by Bell Laboratories to replace hot and fragile valves. MICROPHONE EAR MOULD RAYTHEON VOLUME CONTROL 1951 Raytheon begins mass production but technical issues quickly dampen progress. ON/OFF SWITCH TENITH 1952 BATTERY COMPARTMENT Zenith develops moisture-resistant transistors. TEXAS INSTRUMENTS Transistor systems were much smaller and used far less power. Smaller batteries meant the birth of many of the hearing aid styles we see today. 1954 Silicon transmitters produced to create more effective hearing aids. 1970s Innovation & invention The invention of the microprocessor in the 1970s enabled manufacturers to make hearing aids smaller and more powerful. Hybrid hearing aids using bined digital and analogue circuitry were first patented in 1977, further increasing the flexibility designers had in serving the hearing-impaired population. 1980s wwwww and 90s Rise of the Phoenix SKIN INTERNAL COIL EXTERNAL COIL RECEVER BONE Digital signal processing chips (DSP) were introduced in 1982 and were quickly taken on by the hearing aid industry, with the first DSP hearing aid being released by Project Phoenix in 1988. AUDITORY NERVE COCHLEA Although the technology was better, it represented a backwards step in terms of the size and usability of the hearing aid. By the mid-90s, however, the first fully- digital behind-the-ear and in-the-ear hearing aids - with computing capacity of 40 million instructions per second - were being mass produced. IMPLANTED ELECTRODES MICROPHONE SPEECH PROCESSOR Present MAWMAI Hearing aid technology has now developed to such a degree that digital devices capable of alleviating moderate hearing loss can now be secreted inside in the ear canal itself, making it invisible. It means a whole new group of people put off by wearing a visible hearing aid can enjoy the benefits of enhanced hearing. VESTIBULAR NERVE COCHLEAR NERVE COCHLEAR EXTERNAL AUDITORY CANAL Looking to the future The stem of the problem Sheffield University recently demonstrated stem cells have the potential to restore hearing. An injection of stem cells into ears of gerbils saw on average, the restoration of 45% of hearing ability. Next stage is to develop a way of testing this on humans. Next five years Laser brains TYMPANIC MEMBRANE 5 KHz Currently at clinical trial stage, the 'ear-lens' is a transducer mounted on the ear drum, receiving a laser signal from the external part of the aid mounted behind the ear. The transducer converts this 6 KHz laser signal into a physical vibration on the ear drum itself. The advantage of this system is that it has a much wider frequency range than most conventional hearing aids. 16 KHz Five to ten years You have the power Wwww Within the next decade, it is thought that development will be completed on a hearing aid that is fully-implanted in the ear. What about batteries, you say? This new system will use inductive charging, meaning the energy from the human body actually recharges the battery. 20 to 30 years Good vibrations Much scientific study is currently being dedicated to cochlea regeneration. SKIN ----> This involves persuading the degenerated cells in the inner ear to regrow, or possibly prompt surrounding cells to transform their cell type. The cells being targeted are the hair cells, the ones which transform .---> ---> FAT ---> STEM CELL HAIR CELL BLASTULA vibrations into neural PATIENT-DERIVED SOURCES signals. This research is still at theoretical stage, with scientists still trying to find a way to safely prompt these cells to change their behaviour, UMBILICAL CORD BLOOD FREQUENCY FREQUENCY FREQUENCY The hearing aid has performed a vital function for those suffering from hearing loss for nearly two centuries, but like any other electrical technology, they have developed rapidly with the introduction of the microprocessor in the latter part of the 20th century. Hear today... But what tomorrow? From the ear horn to stem cell research, we take a look back at the history of the hearing aid to see how these devices have evolved over the years... 1800s The earliest hearing aids Essentially nothing more than horn-style devices designed to capture more sound and direct it into the ear canal - first became popular in the 1800s. 1890s The first electric hearing aid In 1898, the first electric hearing aid was created by Miller Reese Hutchison. A portable carbon transmitter was used to amplify weak signals using an electric current, based on the principle used in the telephone. Wearable and practical instruments were available from 1902, but were not in popular use until the 1940s. Even then, they only had the power to correct moderate hearing loss. Carbon Microphone DIAPHRAGM (FLEXIBLE ELECTRODE) SOUND WAVES SIGNAL ---> CARBON GRANULES FIXED ELECTRODE VOLTAGE SOURCE (BATTERY) 1920s Hot and heavy Naval engineers patented the first vacuum-tube hearing aid in 1920, naming it the Vactuphone. This device used a telephone transmitter to convert sound into electrical signals, which were then amplified once they reached the receiver. The Vactuphone had more power than carbon aids and was portable, but required two batteries at a time when they were expensive. 1950s Race to the new style EAR HOOK 1950 Bell Laboratories CONNECTING TUBE The first transistors were developed by Bell Laboratories to replace hot and fragile valves. MICROPHONE EAR MOULD RAYTHEON VOLUME CONTROL 1951 Raytheon begins mass production but technical issues quickly dampen progress. ON/OFF SWITCH TENITH 1952 BATTERY COMPARTMENT Zenith develops moisture-resistant transistors. TEXAS INSTRUMENTS Transistor systems were much smaller and used far less power. Smaller batteries meant the birth of many of the hearing aid styles we see today. 1954 Silicon transmitters produced to create more effective hearing aids. 1970s Innovation & invention The invention of the microprocessor in the 1970s enabled manufacturers to make hearing aids smaller and more powerful. Hybrid hearing aids using bined digital and analogue circuitry were first patented in 1977, further increasing the flexibility designers had in serving the hearing-impaired population. 1980s wwwww and 90s Rise of the Phoenix SKIN INTERNAL COIL EXTERNAL COIL RECEVER BONE Digital signal processing chips (DSP) were introduced in 1982 and were quickly taken on by the hearing aid industry, with the first DSP hearing aid being released by Project Phoenix in 1988. AUDITORY NERVE COCHLEA Although the technology was better, it represented a backwards step in terms of the size and usability of the hearing aid. By the mid-90s, however, the first fully- digital behind-the-ear and in-the-ear hearing aids - with computing capacity of 40 million instructions per second - were being mass produced. IMPLANTED ELECTRODES MICROPHONE SPEECH PROCESSOR Present MAWMAI Hearing aid technology has now developed to such a degree that digital devices capable of alleviating moderate hearing loss can now be secreted inside in the ear canal itself, making it invisible. It means a whole new group of people put off by wearing a visible hearing aid can enjoy the benefits of enhanced hearing. VESTIBULAR NERVE COCHLEAR NERVE COCHLEAR EXTERNAL AUDITORY CANAL Looking to the future The stem of the problem Sheffield University recently demonstrated stem cells have the potential to restore hearing. An injection of stem cells into ears of gerbils saw on average, the restoration of 45% of hearing ability. Next stage is to develop a way of testing this on humans. Next five years Laser brains TYMPANIC MEMBRANE 5 KHz Currently at clinical trial stage, the 'ear-lens' is a transducer mounted on the ear drum, receiving a laser signal from the external part of the aid mounted behind the ear. The transducer converts this 6 KHz laser signal into a physical vibration on the ear drum itself. The advantage of this system is that it has a much wider frequency range than most conventional hearing aids. 16 KHz Five to ten years You have the power Wwww Within the next decade, it is thought that development will be completed on a hearing aid that is fully-implanted in the ear. What about batteries, you say? This new system will use inductive charging, meaning the energy from the human body actually recharges the battery. 20 to 30 years Good vibrations Much scientific study is currently being dedicated to cochlea regeneration. SKIN ----> This involves persuading the degenerated cells in the inner ear to regrow, or possibly prompt surrounding cells to transform their cell type. The cells being targeted are the hair cells, the ones which transform .---> ---> FAT ---> STEM CELL HAIR CELL BLASTULA vibrations into neural PATIENT-DERIVED SOURCES signals. This research is still at theoretical stage, with scientists still trying to find a way to safely prompt these cells to change their behaviour, UMBILICAL CORD BLOOD FREQUENCY FREQUENCY FREQUENCY