Why does Ilyn clack when he laughs?
Caveat: I'm a Speech and Language Therapist who doesn't specialise in glossectomy with too much time on my hands
One of Ilyn's defining characteristics is the fact that 14 years before we're introduced to him in AGOT, he was mutilated by Aerys Targaryen:
While the removal of a person's tongue using hot pincers is barbaric, we do have a modern analogue: glossectomy.
As a result of his glossectomy, GRRM doesn't include any verbal output from Ilyn in the text (i.e spoken words).
However, there is one distinct vocal (i.e using voice but not necessarily words, such as humming, singing, or individual sounds) characteristic that we see repeatedly from Ilyn: the clacking sound that tells us that he's amused.
Here's the thing about laughter: unlike speech, where precise tongue movements are needed to form sounds, laughter doesn't require the same level of articulation.
This MRI of spontaneous laughter shows us that the main processes in producing laughter are movement of the velum (soft palate), movement of the pharyngeal walls, and retraction and lowering of the tongue. Given what we know about Ilyn, we can assume the only process that's interrupted here is the retraction and lowering of the tongue.
So why exactly does he clack when he laughs?
First of all, we need to define what is meant by clacking.
The broad dictionary definition is a sharp, repetitive sound made when two hard surfaces quickly strike each other. In the context of vocal sounds, we need to consider a few possibilities:
- Speech sounds
- Clicks
- Speech sounds
We're assuming, as Aerys had his "tongue ripped out", there is a significant portion of Ilyn's tongue missing. Because of this, for place of articulation I'm going to be focusing on the portion of the IPA chart from palatal sounds to glottal sounds. Because clacking requires two surfaces striking each other, there are three different manners of articulation which we could consider: plosives, taps/ flaps, and trills. However, when we consider both place and manner of articulation together, there are only a few sounds which Ilyn could produce, all plosive sounds (where articulators fully close, stopping airflow, and then release it with a burst).
Given that the sounds are described as "clacking" rather than "gulping", I'm going to assume that the sounds are voiceless plosives (typically align more with /k/ sounds) rather than voiced plosives (typically align more with /g/ sounds). This gives us three different ideas of what the clacking might sound like (I'm eliminating the glottal stop as this is a complete closure of the vocal cords, e.g the space between the first and second words in uh-oh):
We can also use the IPA to transcribe clicks, which are used in some African languages.
Again, given that we can assume a significant portion of Ilyn's tongue is missing, we can narrow this down to one type of click, as it's the only type of click which does not require the tip of the tongue: an alveolar lateral click.
Yes, but you still haven't explained why he clacks rather than laughs.
There's a reason I still haven't given a clear explanation: it doesn't make much sense.
We've seen in the MRI above that laughter requires lowering and retraction of the tongue, but all the examples of clacking sounds require the raising of the tongue in order for it to strike another articulator to produce the required sound.
There's one exception to producing laughter where the tongue is raised rather than lowered or neutral: giggling.
TL;DR: Ilyn clacks when he laughs because he's a giggler.