Synergists and the antagonists for Erector spinae, coracobrachialis, longus capitis?
Answer:
Erector Spinae are extensors of the spine. The antagonists at the neck would be the nouns flexors (ie, sternocleidomastoid, the longus coli and the longus capitis) at the trunk, it would be the rectus abdominis and the obliques. The synergists would be the hip extensors (gluteii) and the latisimus dorsi.
For the coracobrachialis, it's origin/insertion indicates it is a shoulder flexor and adductor. As a shoulder flexor the synergists would include the deltoids (anterior), the pectoralis, the serratus anterior, the rotator cuff and the long head of biceps. As an adductor, its synergists would include the pectorals, the lats and teres crucial. It's agonist would include the shoulder extensors (posterior deltoid, lats, long heaf of triceps and teres major). The agonists for adduction would include the middle deltoid and the rotator cuff.
For the longus capitis, since it is a deep collar flexor, its antagonist would include the suboccipital muscles (Rectus capitis posterior major, Rectus capitis posterior minor, Obliquus capitis superior and Obliquus capitis inferior) and the philosophical muscles (Intertransversarii, Short rotatores, Long rotatores, Multifidus, Semispinalis capitis, Semispinalis cervicis, Splenius capitis and Splenius cervicis). Its synergists would include the neck flexors primarily the sternocleidomastoid and most of the anterior muscles of the nouns.
Hope this helps.
I simply took a major exam surrounded by anatomy- unfortunately I am away and don't own my books with me. BUT roughly speaking: erector spinae are extensors of the spine. I'm not sure anything is precisely a synergist; the closest article would probably be the transversospinalis group, which sidebends, rotates and maybe extends. Antagonists would be the abdominal muscles. Coracobrachialis is a flexor of the forearm; biceps and brachioradialis would be synergists and triceps and anconeus would be antagonists. longus capitis is a flexor of the d¨Ścolletage, with sternocleidomastoid and othere anterior nouns muscles; it is antagonized by posterior neck muscles such as the erector spinae, and splenius cervicis. This is not a faultlessly precise answer but it should give you a starting point. If you want to look it up surrounded by a book, the BRS series anatomy book or Moore's Essential Clinical Anatomy would have to-the-point information and charts.