its not any joint, its the size of a penis(for females)/ yummyness of the vagina (for males) which causes the head of opposite sex move their head (pleasurably aroused ofcourse).
Your shoulder joint allows you to raise your arm above your head.
pivot joint
Pivot.
the fixed the fixed
the fixed the fixed
The only movable joint in the head is the temporomandibular joint (TMJ), which connects the jawbone to the skull. This joint allows for movements necessary for chewing, talking, and facial expressions.
It's called the pivot joint. It allows your head to move from side to side.
The joint that allows you to turn your head from side to side is the atlanto-axial joint, formed between the first and second cervical vertebrae (C1 and C2). This joint enables the rotation of the head without moving the entire spine.
This joint forms a pivot motion. When you turn backwards rapidly to open a door or when a dancer pivots on one foot these are the motions a pivot allows. In the joint between C1 and C2, this pivot allows you to turn your head to the left and to the right.
The axillary recess is a space within the shoulder joint capsule that lies below the head of the humerus. It is located in the armpit area and allows for increased range of motion in the shoulder joint.
It's called the pivot joint. It allows your head to move from side to side.
The cervical(neck) vertebrae. The joint formed by C1 and C2, also known as the atlas and axis.