Weird Inflection -されていかん


I am reading Alita Battle Angel, and I came across a sentence that I do
understand, but for some reason is conjugated to the negative. Please could
someone break the sentence down for me?

> > (After becoming just your head, you have become rather talkative)
>>

>> 取｛と｝り憑{つ｝く体によって知能レベルがどうも **左右{さゆう}されていかん…**

>>

>> (My intelligence is influenced by the body I possess...)

My understanding is that どうも gives the meaning of 'somewhat, fairly, quite',
but I do not know why いかない is not in the plain form. Also, what does it do
when the passive form of the main verb is used?




いかん in this sentence means "no good", "of no use", "it sucks", etc. It's
adding the speaker's feeling about the mentioned fact (左右される). いかん is almost a
lexicalized expression, and it is also used like English "oops", "don't do it"
or "oh my gosh". It sounds a little pompous or dialectal.

Related:

  * [What does ても＋いかん do?](https://japanese.stackexchange.com/q/28856/5010)
  * [Meaning of いかんしょ in following sentence](https://japanese.stackexchange.com/q/28280/5010)
  * [Use of "いかん" in the following sentences](https://japanese.stackexchange.com/q/61398/5010)




いかん in this sentence means "no good", "of no use", "it sucks", etc. It's
adding the speaker's feeling about the mentioned fact (左右される). いかん is almost a
lexicalized expression, and it is also used like English "oops", "don't do it"
or "oh my gosh". It sounds a little pompous or dialectal.

Related:

  * [What does ても＋いかん do?](https://japanese.stackexchange.com/q/28856/5010)
  * [Meaning of いかんしょ in following sentence](https://japanese.stackexchange.com/q/28280/5010)
  * [Use of "いかん" in the following sentences](https://japanese.stackexchange.com/q/61398/5010)

