Do speakers with heavy accents find it easier to understand their own accent than a more standard accent?

Question

As a speaker of a fairly standard North American English accent, I occasionally find it difficult to understand people who speak with a heavy accent. I've always been curious about what exactly makes accents difficult to understand, and it occurred to me that intelligibility could either be an absolute property (for example, driven by the brain's ability to distinguish phonemes) or relative (determined by the brain's ability to 'pattern match' to known phonemes).

If it were true that intelligibility is absolute, then I would expect that any listener would tend to have an easier time understanding speech in a "clear" or "common" accent, even if they natively speak with a heavier accent. On the other hand, intelligibility being relative would suggest that what is a "clear" accent to one person would be a "heavy" accent to another. Has this sort of experiment been done, and what does it tell us about intelligibility?

Also, I realize that this could also possibly be different between first- and second-language speakers - presumably people growing up in a community naturally understand other speakers from that community clearly, but perhaps two speakers with the same native language who are conversing in a second language may struggle to understand each other more than they would a native speaker.

Answer 1

I also speak Standard North American English, and encounter problems understanding and being understood. For instance, a "root" is a [rʊt] for me, and if I ask a Kenyan what their word for [rʊt] is, they will have no idea, but if I ask for a [ruwt] then they can tell me. People from outside my US zone sometimes giggle when I say [rʊt]. My dialect can be particularly hard to follow if you don't know the patterns of syllable reduction and glottalization that typify Our Language ("tear" and "terror" are a minimal pair for vowel length in my dialect).

I witnessed a Kenyan guy pointing out a [reobad] in a tree, which a bunch of Californian passengers thought was a "rail bird", and not a [lɛpɹ̩d]. My advantage was that I'm familiar with that dialect. I also found Newcastle-area English to be utterly incomprehensible for about a week, even though I knew all of the phonemes and had heard all of those sounds plus a lot more. It's just that I had never encountered that particular system before.

The "heaviness" of an accent is really a measure of your subjective ability to map from what you hear to a particular meaning. It's actually not just pronunciation, quite often those other dialects have constructions that don't make immediate sense even if written down. There's a certain amount of quaint difference between US and posh UK English, but I have a hard time, sometimes, with non-posh UK especially working class lexicon.

Intelligiblity is relative: relative to the complexity of mapping from one system to the other. The reason why RP is not so difficult for me to understand is that I've been exposed to bits of it most of my life, thanks to Monty Python and their ilk. So I would look to prior exposure as the factor that makes an accent easy vs. hard – it's not something intrinsic to the system.