Nuanced neurons help distinguish voices in a crowded room

In order to focus on a particular conversation, listeners need to be able to focus on the voice of the speaker they wish to listen to. This process is called selective attention and it has been long known that it happens in the auditory cortex, which processes speech information.

Selective attention helps the brain to modulate sound information and to prioritise information over the background noise. However, what triggers selective attention in the auditory cortex has been debated by scientists.

In a study published in eLife, the researchers from Imperial College London describe how they investigated the structures downstream of the auditory cortex. In particular, they looked at the contribution that the auditory brainstem, which sits below the auditory cortex, makes to the selective attention process.

According to Imperial, the researchers set up non-invasive experiments with 14 participants who listened to two competing conversations. Electrodes were fitted to the participants' heads and connected to a computer, which relayed the brain readings in the auditory brain stem. Algorithms devised by the team then decoded the information gathered by the electrodes.