The effect of familiar male voices on neurons

male zebra finch trying to impress female (Max-Planck)

Zebra finches are a popular model for language learning because unlike most research animals which may have instinctual vocalizations, zebra finches (the male ones at least) learn their signature song from experience.

The importance of social experience in male song learning is clear, but what about the effect of social experience on the female response to the male voice?

Menardy et al., 2012 (figure 2C)

Menardy et al., (2012) have recently analyzed the neural response in females to the male distance calls (not songs).  They tested the  response in anesthetized birds, but also in awake, alert birds. To do so, they used a nifty little recording device that they mounted on the back of the females.


They tested the response of the neurons in the caudomedial nidopallium (NCM) to the calls of the female's mate (4 months spent together), a non-mate familiar male (3 days spent together), and an unfamiliar male (complete stranger).

In general, the neurons in the female NCM responded more strongly to the calls of the males that they knew than to the stranger's call. 

Menardy et al., 2012 (figure 5A)

So why is this and what does it mean? The authors point out that this change in neural response could be a result of extensive social interactions (the female bird spent some quality time with the mate and the familiar male), or it could be a result of having heard the call before. 

In other words, Is the NCM encoding a recognition signal ('ah, that's Nick's voice') or a familiarity signal ('I've heard this sound before')?

It is likely that some form of neuroplasticity is taking place during the male-female interactions, but the mechanisms and the meaning behind it are not clear yet. Some interesting experiments might be to test the effect of traditional 'learning disruptors' (such as protein synthesis inhibitors) on this neural preference for familiarity. 

© TheCellularScale


Menardy F, Touiki K, Dutrieux G, Bozon B, Vignal C, Mathevon N, & Del Negro C (2012). Social experience affects neuronal responses to male calls in adult female zebra finches. The European journal of neuroscience, 35 (8), 1322-36 PMID: 22512260