What's on your neck 颈?

颈 [giaŋ55], neck or throat,  is the inspiration of  quite a few words in Taishanese. The words can be roughly divided into two groups.
The first group has to do with food ingestion. I'm puzzled that Taishanese tends to use throat as a component of the  bi-syllable words instead of the more typical mouth or stomach as in Cantonese or Mandarin.  After all, the throat is just a connection between the two functional organs. 
    咸颈 [ham22 giaŋ55]   'salty-throat'        salty
    腻颈 [nɔu22 giaŋ55]    'greasy-throat'     greasy
    鲠颈 [kaŋ55 giaŋ55]     'choke-throat'     bony
    颈赤 [giaŋ55 tiak33]     'throat-ache'       gluttonous
    颈渴 [giaŋ55 hɔt33]      'throat-thirsty'     thirsty
    颈喉 [giaŋ55 hǝu21]    'neck-throat'         throat
    肿颈 [dzǝŋ55 giaŋ55]   'swollen-throat'    to have the mumps
The next group is even more surprising: it is related to temperament. Other than stiff neck which is both literally and semantically equivalent to its Cantonese cousin as well as English, all others are quite unique.
    丑颈 [tsiu55 giaŋ55]   'ugly-neck'     of bad temper
    好颈 [hɔu55 giaŋ55]   'good-neck'   of good temper
    牛颈 [ŋǝu22 giaŋ55]   'cow-neck'     stubborn
    硬颈 [ŋaŋ32  giaŋ55]   'stiff-neck'     stiff neck
    拗颈 [niu55 giaŋ55]     'twist-neck'    in anger
    蛮颈 [man22 giaŋ55]   'wild-neck'     rude and stubborn
    顶颈 [?ein22 giaŋ55]   'push-neck'    talk back, quarrel
    颈紧 [giaŋ55 gin55]    'neck-tight'     impatient