Muscle Actions

orbicularis oculi

closes eye

obicularis oris

close mouth

buccinator

suck through straw

masseter

jaw closure

temporalis

retracts mandible

frontalis

raises eyebrows

mentalis

wrinkle chin

stylohyoid

elevate hyoid

mylohyoid

raises roof of mouth

sternohyoid

depress larynx

thryohyoid

elevate larynx

sternocleidomastoid

neck rotation

platysma

tenses skin in neck

pectoralis major

adducts arm

serratus anterior

stabilizing pectoral girdle

deltoid

arm abduction

external intercostals

pull ribs together

internal intercostals

pull ribs together

rectus abdominis

flexes trunk

external abdominal oblique

compress abdomen

internal abdominal oblique

compress abdomen

transversus abdominis

wraps abdomen

latissimus dorsi

arm extension

trapezius

stablilize scapula

teres major

adducts arm

rhomboids

stabilize scapula

erector spinae

back extension

psoas major

thigh flexion