According to a research conducted at the University of Leipzig in Germany by Anja Roye and colleagues, the instant you hear a cellphone ring, your brain reacts in a unique way if the ringtone matches that of your own phone. Roye says that our brains store templates for our own ringtones, allowing it to distinguish quickly between familiar and unfamiliar tones.
The team recorded the text-alert tones of 12 volunteers, then played them all the tones, at the same volume and in a random order, while recording their neural activity via scalp electrodes. Brain areas linked to hearing and memory retrieval lit up when participants heard their own ringtone or the one they were assigned. However, after just 40 milliseconds, more neurons were active when volunteers heard their own ringtone than someone else’s, even if this was the one they were assigned.
Anecdotal reports and also empirical observations suggest a preferential processing of personally significant sounds. The utterance of one’s own name, the ringing of one’s own telephone, or the like appear to be especially effective for capturing attention. However, there is a lack of knowledge about the time course and functional neuroanatomy of the voluntary and the involuntary detection of personally significant sounds.
To address this issue, the research team applied an active and a passive listening paradigm, in which male and female human participants were presented with the SMS ringtone of their own mobile and other’s ringtones, respectively. Enhanced evoked oscillatory activity in the 35-75 Hz band for one’s own ringtone shows that the brain distinguishes complex personally significant and nonsignificant sounds, starting as early as 40 ms after sound onset.
While in animals it has been reported that the primary auditory cortex accounts for acoustic experience-based memory matching processes, results from the present study suggest that in humans these processes are not confined to sensory processing areas.
In particular, the team found a coactivation of left auditory areas and left frontal gyri during passive listening. Active listening evoked additional involvement of sensory processing areas in the right hemisphere. This supports the idea that top-down mechanisms affect stimulus representations even at the level of sensory cortices. Furthermore, active detection of sounds additionally activated the superior parietal lobe supporting the existence of a frontoparietal network of selective attention. [source, via]