Hearing Aids and Halacha – Part 3: Cochlear Implants

The human auditory system functions through the intricate interactions of thousands of tiny hair cells located in the cochlea, an internal structure of the ear. As sound waves enter the ear, they cause these hair cells to vibrate, generating electrical signals that are sent to the brain through connected nerves. This process enables the brain to interpret and perceive sound effectively.

Hearing impairment often arises from the loss of hair cells in the cochlea. The greater the number of missing hair cells, the more significant the hearing impairment. Conventional hearing aids provide a solution by amplifying sound, effectively acting as small speakers. With a reduced number of hair cells, the remaining ones may become less responsive to typical sound levels. By boosting the volume, these devices stimulate the remaining hair cells, allowing them to transmit sound waves to the brain more effectively. This variation in the effectiveness of hearing aids among individuals is due to differences in the condition and responsiveness of their remaining hair cells, leading to some users experiencing optimal hearing while others may not.

This issue lies at the heart of a Halachic debate explored in last week’s essay. Some Poskim argue that because the sound produced by the hearing aid is not the original sound but an artificially amplified imitation, the listener does not hear the authentic voice of a person or the Shofar, and thus does not fulfill his obligation. Conversely, others maintain that since the artificial sound is essentially a continuation and enhancement of the original sound, it should be regarded as equivalent to the original.

Unlike traditional hearing aids, a cochlear implant uses a different technique. It converts sound directly into electrical signals that it transmits to the auditory nerves, bypassing the cochlea and its hair cells. Consequently, the brain receives the original sound (rather than an artificially amplified or generated sound), but instead of the cochlear hair cells transmitting the signal, the implant does so directly to the brain.

For this reason, some Poskim, such as R’ Moshe Sternbuch Shlit”a (cited in the Kovetz Ateres Shlomo published by the Machon haMada’i Technologi, Issue 9 p153), hold that even those who are stringent regarding hearing aids would consider hearing via cochlea implants to be Sh’mia.

At the outset of his Teshuva, R’ Sternbuch acknowledges the contrary view:

There is a basis for the argument that a person is not Yotze, because although he can hear, the quality of his hearing is not the same as ours. Some say that this is why his speech is also different [than that of people with intact hearing]. Ultimately, since the function – namely, hearing – is not the same as regular hearing, he does not fulfill his obligation.

Nevertheless, he concludes that the listener is Yotze:

 Since this is his natural manner of hearing… and since the device is concealed in the ear… it suffices even though it is not the same as other people’s hearing.

He also adds the view of the Chazon Ish that even with a regular hearing aid a person is considered to be hearing the original sound. This would certainly be true of a cochlear implant.

However, haGaon Rav Asher Weiss Shlit”a holds that a person does not fulfill his obligation with either hearing aids or cochlear implants. His position is explained in a Teshuva published in the Kovetz Or haShabbos (Issue 19, p8) and elaborated on in a response to the authors of the sefer Ya’ir li Ozen. He maintains that whenever a Mitzvah is dependent upon hearing, it can only be fulfilled with the natural ear. An artificial intervention cannot qualify as Sh’mia. In Rav Asher’s words:

There is no concept of hearing other than through the auditory organs in the ear, which is alone defined as Sh’mia concerning all laws of the Torah that require Sh’mia. [This applies] both to the Mitzva of Shofar, which fundamentally requires Sh’mia, and the Mitzva of Megilla, which relies upon the Din of “Shome’a k’Oneh”. However, in the case of the cochlear implant that bypasses the auditory structures of the ear and directly transmits sound to the auditory nerves in the brain, this is not defined as Sh’mia. This appears to be the primary opinion l’Halacha.

A similar position was held by R’ Shaul Breisch, Av Beis Din of Zurich (in his Teshuva published in the Kovetz Nezer haTorah Issue 18 (Elul 5768) p335). After consulting with experts, he ruled that both hearing aids and cochlear implants have the same essential issue:

It all revolves around the same principle – the device captures sounds and emits those same sounds. However, in reality, the sounds now originate from the machine; one does not hear the actual voice of the speaker but rather the sounds of wood and stone.

It should be noted that all of this pertains to the Ikar haDin. Rav Asher concludes:

Nevertheless, since this concerns people who are completely unable to hear except through this device, they should certainly use it. This is because we do not have an explicit Halacha l’Moshe miSinai on this matter [and] there is no definitive argument. However, they certainly cannot recite a blessing over this Sh’mia.