Retraction Note: Neuromuscular Specializations of the Human Hypopharyngeal Muscles

Cranial nerves are responsible for transmitting motor and sensory information between the brain and various parts of the body. There are twelve pairs of cranial nerves. While the first six innervate the head and neck, the latter six nerves innervate the head and neck, as well as organs and tissues in the thoracic and abdominal cavities. They facilitate communication, expression, and autonomic control within the human body.
Facial Nerve (Cranial Nerve VII)
Cranial nerve VII, or the facial nerve,...

The anterior neck muscles are the group of muscles covering the front part of the neck. These muscles are classified into three subgroups. The first one is the superficial muscles, the most visible muscles in the front of the neck. It includes the platysma and sternocleidomastoid. The second group is the suprahyoid muscles, located above the hyoid bone. This group comprises the digastric, mylohyoid, geniohyoid, and stylohyoid. Lastly, the infrahyoid muscles are found below the hyoid bone and...

The hyoid bone is a small U-shaped bone located in the upper neck at the level of the inferior mandible, with its tips pointing posteriorly. It does not directly articulate with any other bone in the body. The hyoid acts as the attachment site for the tongue, the larynx, and the pharynx. It is held in position by a series of small muscles attached from above or below. These muscles help to move the hyoid up/down or forward/back in coordination with movements of the tongue, larynx, and pharynx...

The pharynx, a tubular structure framed by skeletal muscle and lined with mucous membrane, extends continuously from the nasal cavities. It is segmented into three major areas: the nasopharynx, oropharynx, and laryngopharynx.
Nasopharynx
The nasopharynx, bordered by the conchae of the nasal cavity, serves exclusively as an air conduit. In its superior region, the pharyngeal tonsils or adenoids are located. These tonsils are clusters of lymphoid reticular tissue akin to a lymph node. The precise...

Swallowing, otherwise known as deglutition, facilitates the transport of food from the mouth to the stomach. It is a multifaceted process that involves both the tongue and the muscles of the throat and esophagus. Saliva and mucus aid in this process, which takes approximately 4 to 8 seconds for semi-solid or solid food and around 1 second for liquids or very soft food.
Swallowing can be divided into three stages: the voluntary phase, the pharyngeal phase, and the esophageal phase. Although the...

The nervous system consists of complex motor neuron circuits, including upper motor neurons originating from the cerebral cortex and lower motor neurons starting in the spinal cord, coordinating both voluntary and involuntary movements. Among these, somatic motor neurons activate skeletal muscles and are classified into alpha, beta, and gamma types. Alpha neurons are vital for voluntary movement coordination, while gamma neurons adjust muscle spindle sensitivity, and the function of beta...