Intelligibility between Tohoku dialects


I have heard that not only can people outside of Tohoku have trouble
understanding the dialect, but I have also heard that people from different
regions of Tohoku can't understand each other either. To what extent is this
true? The common example I hear are between Aomori dialects like Tsugaru-ben,
but would people between regions like Miyagi and Yamagata have this same
difficulty? After doing some research, it seems that the sound changes are
fairly similar, or at least known between dialects, so is this
unintelligibility due to the accent or due to vocabulary and grammar
differences?




Here are some data points on the subject (results from Google searches on
terms "東北方言 お互い 理解") :

From <https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q11184915261>

> 私は青森県民ですが、 秋田・岩手は割と似てるところもありますよ。 とはいえ、同じ青森でも津軽と南部は全く違う方言で、
> お互いの高齢者が話してる内容は結構わかんない部分もあります。

i.e "I am from Aomori. It is pretty similar to Iwate. But even in Aomori:
Tsugaru and Nanbu region are so different, old people talking together would
have some trouble understanding each other"

From <https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q11153633351>

> 同じ南部なので基本的には通じます。 ただ、同じ南部でも盛岡と八戸とで全く同じように話すかと言えばやっぱり違います。
> また、岩手の伊達と南部でも互いに通じない言葉も多々ありますが、青森の南部VS津軽ほどではありません。岩手沿岸部や八戸などは独特のイントネーションが特徴です。正直、八戸も含め、沿岸部は標準語に近いとは言えません。

i.e "[Aomori and Iwate] have same Nanbu language and basically understand each
other. But in Nanbu, Morioka and Hachinohe are not exactly the same. Also,
there are Nanbu words that are not understood in Date, but not to the extent
of Nanbu vs. Tsugaru. Iwate seaside or Hachinohe have specific intonations.
I'd say those two are pretty far from standard Japanese"

From <https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1397496063>

> 同じ山形でも地域によって方言も違ってくるみたい

i.e "It seems there are language variations among Yamagata itself as well"

From <https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q10107826150>

> 盛岡市と青森市、年代によっては成立しません。 お年寄りの方は単語から違う方言を使います。 青森市と八戸市も、お年寄り同士は厳しいです。

i.e "Persons of a certain age of Morioka and Aomori could hardly understand
each other. Same between older people from Aomori and Hachinohe"

* * *

And here is a transcription (might not be 100% accurate, I don't know the
technical terms) of the [chart from the Japanese wikipedia page on the topic,
illustrating some differences in pronunciation between the
languages](https://ja.m.wikipedia.org/wiki/%E6%9D%B1%E5%8C%97%E6%96%B9%E8%A8%80#%E6%9D%B1%E5%8C%97%E6%96%B9%E8%A8%80%E3%81%8A%E3%82%88%E3%81%B3%E9%96%A2%E6%9D%B1%E6%96%B9%E8%A8%80%E3%81%AE%E9%9F%B3%E9%9F%BB%E3%81%AE%E6%AF%94%E8%BC%83%E8%A1%A8):

[code]

    ----------------------------------------------------------------------
    |                          | Northern | Southern |  East   |  West   |
    |                          |  Tōhoku  |  Tōhoku  |  Kantō  |  Kantō  |
    ----------------------------------------------------------------------
    | [i]/[u] pronounced as    |   (Y)    |   (Y)    |   (Y)   |   (N)   |
    | "central vowels" [ï]/[ɯ̈] |          |          |         |         |
    ----------------------------------------------------------------------
    | standard [ɛ] pronounced  |   (Y)    |   (Y)    |   (Y)   |   (N)   |
    | as closed vowel [e]      |          |          |         |         |
    ----------------------------------------------------------------------
    | mixing of [i] and [e]    |   (Y)    |   (Y)    |   (Y)   |   (N)   |
    ----------------------------------------------------------------------
    | voicing of internal      |   (Y)    |   (Y)    |   (Y)   |   (N)   |
    | consonants [k]/[t]       |          |          |         |         |
    ----------------------------------------------------------------------
    | nazalization of internal |   (Y)    |   (Y)    |   (N)   |   (N)   |
    | "dull consonants"        |          |          |         |         |
    ----------------------------------------------------------------------
    | merging of pairs         |   (Y)    |   (Y)    |   (N)   |   (N)   |
    | shi/su, chi/tsu, ji/zu   | (in [i]) | (in [u]) |         |         |
    ----------------------------------------------------------------------
    | syllabeme phenomenon     |   (Y)    |   (N)    |   (N)   |   (N)   |
    ----------------------------------------------------------------------
    | absence of accent        |   (N)    |   (Y)    |   (Y)   |   (N)   |
    ----------------------------------------------------------------------
    
[/code]

