MOR 345 quiz 1 Terms and Studyguides

List the Acquired Facial Markings.

- Nasolabial Sulcus ~Transverse Frontal Sulci ~ Interciliary Sulci ~ BuccoFacial Sulcus ~ Superior Palpebral Sulcus ~ Inferior Palpebral Sulcus ~ Optic Facial Sulci ~ Labial Sulci ~ Mandibular Sulcus ~ Platysmal Sulci ~ Cords of the Neck

List the natural facial markings.

- Philtrum ~ Nasolabial Fold ~ Nasal Sulcus ~ Oblique Palpebral Sulcus ~ Angulus Oris Eminence ~ Angulus Oris Sulcus ~ Labiomental Sulcus ~ Submental Sulcus ~ Dimples

According to the lesson notes, what are three examples of pre-embalming restorative art treatments?

- aligning features - temporary sutures - suturing of clean cuts

Compare and contrast the condyle and the coronoid process.

- condyle: posterior, articulating process of the ramus of the mandible - coronoid process: anterior, non-articulating process of the ramus of the mandible

List three examples of "major" restorative art procedures

- feature reconstruction - attachment of dismembered body parts - deep wound cavity treatment

List and describe the 4 dimensions of form in Restorative Art.

- length: a vertical dimension - width: the dimension of an object measured across from side to side. - projection: The act of throwing forward; a part extending beyond the level of its surroundings. - contour: the outline or surface form

List the 3 heads of the Quadratus labii Superioris muscle.

- levator labii superioris alaque nasi - levator labii superioris - zygomaticus minor

List three examples of "minor" restorative art procedures.

- setting features - simple suturing to close incisions/minor lacerations - minor integumentary waxing

According to the lesson notes, what are three examples of post-embalming restorative art treatments?

- wax restorations - cosmetics - hypodermic tissue building

Describe the forms the Angulus Oris Sulcus may take in the various stages of life. Include Youth (Infancy), Maturity and Old Age.

- youth - angular - maturity - crevice extending inferiorly and obliquely from the end of the line of mouth closure - old age - can reverse direction and extend into upper integumentary lip.

Describe where the Frontal eminences are located.

1" below the hairline

How many basic facial profile views are there? What are they

3; convex, concave, vertical

glabella

A single bony prominence of the frontal bone located between the superciliary arches in the inferior part of the frontal bone above the root of the nose.

Describe the Transverse Frontal Sulci.

Acquired horizontal furrows of the forehead (Think Gordon Ramsay's surprised angry face)

Describe the Labial sulci.

Also known as Smoker's Lines - vertical furrows of the lips extending from within the mucous membranes into the integumentary lip

What mark is formed by the Buccinator muscle?

Bucco-facial sulcus (the vertical furrow/wrinkle in the soft tissues of cheek)

symmetry

Correspondence in size, shape, and relative position of parts that are on opposite sides of the face.

Another name for the frowning muscles

Corrugator muscles

Describe the Mandibular Sulcus.

Furrow beneath the mandible which rises vertically on the cheek

Another name for the Zygomaticus Major Muscle

Laughing or Smiling Muscle

Who has a greater prevalence of wrinkles, men or women? Why?

Men, because women have more soft adipose tissue

Name the 4 External Cranial Bones.

Occipital Bone, Parietal Bones, Temporal Bones, Frontal Bone

The sphincter muscle of the mouth

Orbicularis Oris a.k.a. Puckering Muscle

projection

The act of throwing forward; a part extending beyond the level of its surroundings.

restorative art

The care of the deceased to recreate natural form and color.

The Philtrum lies between what two structures?

The columna nase and the medial lobe of the mucous membrane of the upper lip (the nose and upper lip)

Cribiform plate

The horizontal plate of the ethmoid bone separating the cranial cavity from the nasal cavity.

mandible

The horseshoe-shaped bone forming the inferior jaw.

Describe the Labiomental Sulcus

The junction of the lower lip and the chin, which may appear as a furrow

Describe the Oblique Palpebral Sulcus.

The shallow, curving groove below the inner corner of the eyelids

Describe the Angulus Oris Eminence.

The small convex prominence lateral to the end of the line of mouth closure

Levator labii superioris

This is the intermediate or "middle" head of the Quadratus Labii Superioris

Zygomaticus minor

This is the lateral (or outermost) head/belly of the Quadratus Labii Superioris which emphasizes the nasolabial fold

Levator labii superioris alaque nasi (Common elevator)

This is the medial (or inner) head of the Quadratus Labii Superioris

Define what is meant by natural facial markings.

Those markings which may be present at birth

The facial markings produced by the corrugators

Vertical intercilliary Sulci (vertical wrinkles between the eyes)

concave profile / infantine / retrousse

a basic facial form in which the forehead protrudes beyond the eyebrows while the chin protrudes beyond the plane of the upper lip

convex profile

a basic profile form in which the forehead recedes from the eyebrows while the chin recedes from the plane of the upper lip (most common).

Angle of the mandible

a bony angle formed by the junction of the posterior edge of the ramus of the mandible and the inferior surface of the body of the mandible

Alveolar process

a bony ridge found on the inferior surface of the maxilla and the superior surface of the mandible which contains the sockets for the teeth

Sulcus / Furrow / wrinkle

a crevice in the skin accompanied by adjacent elevation

triangular

a frontal head form in which the face is wider between the angles of the mandible than it is at the forehead

round / infantine

a frontal head form in which the head exhibits maximum curvature

square / strong

a frontal head form in which the head is broad and exhibits very little curvature; the forehead is wide and the angles of the mandible are usually low as well as wide

oval

a frontal head form in which the head is generally egg-shaped, with the cranium slightly wider than the jaws

oblong

a frontal head form in which the head is long and narrow throughout.

diamond

a frontal-view geometric head shape which is widest across the cheekbones, narrowing in width in both the forehead and the jaws.

Quadratus labii superioris

a large, 3-bellied muscle extending from the cheekbone and lower rim of the eyesocket to the orbicularis oris

Procerus (Concentrating muscle)

a long, thin slip of muscle over the bridge of the nose that draws the skin of the forehead inferiorly.

Levator palpebrae superioris

a muscle of facial expression which raises the upper palpebra.

Zygomaticus major (Laughing or Smiling muscle)

a muscle of the face which draws the superior lip posteriorly and superiorly

Sternocleidomastoid muscle (SCM)

a muscle of the neck that is attached to the mastoid process of the temporal bone and the sternum and clavicle; forms the lateral border of the neck

maxilla

a paired bone with several processes that form the skeletal base of most of the superior face, roof of the mouth, sides of the nasal cavity, and floor of the orbit

Convex-vertical profile

a profile variation in which the forehead recedes from the eyebrows while the chin and upper lip project equally to an imaginary vertical line.

Convex-concave profile

a profile variation in which the forehead recedes from the eyebrows while the chin protrudes beyond the plane of the upper lip.

eminence

a prominence or projection of a bone

Corrugator (Frowning muscle)

a pyramid-shaped muscle of facial expression which draws the eyebrows inferiorly and medially; located at the medial end of each eyebrow

condyle

a rounded prominence at the end of a bone forming an articulation; the posterior process of the ramus of the mandible

inverted triangle / heart

a three-sided figure whose base is superior to its apex; when used to describe a frontal-view geometric headshape, a head which is wide at the forehead and narrow at the jaw

mental eminence

a triangular projection on the interior portion of the anterior mandible

recession

a type of surface formed by the withdrawal of a part from its normal position.

color

a visual sensation perceived by the eye and the mind due to the activity and vibration of light

Those facial markings which may develop with age are known as

acquired facial markings

Alveolar prognathism

an abnormal protrusion of the alveolar process

Groove

an elongated depression in a relatively level plane or surface

Fold

an elongated prominence adjoining a surface

Bilateral view

an inferior or superior viewpoint which permits the comparison of two sides of an object or facial feature

face

anatomically, the region from the eyes to the base of the chin; physiognomically, the region from the normal hairline to the base of the chin.

The small triangular depression in the anterior part of the angulus oris eminence.

angulus orcis sulcus??

hard palate

anterior portion of the roof of the mouth

frontal (direct view)

anterior; the anterior view of the face or features

What is an alternate term for the vertical facial profile?

balanced

Anterior

before or in front of; an anatomical term of position and direction which denotes the front or forward part

inferior

beneath; lower; the underside of an organ or indicating a structure below another structure; toward the feet

The nasolabial fold lies between what 2 structures?

between the wing of the nose and the corner of the mouth

vomer

bone of the nasal cavity situated between the nasal passages on the median plane; it forms the inferior and posterior portion of the septum of the nose

zygomatic bone / zygoma / malar

bones of the cheek

Those facial bones that form a dome over the nasal cavity

bridge of the nose

Temporalis

broad fan-shaped muscle over the squama of the temporal bone; muscle of mastication which helps to close the mandible; the strongest of the chewing muscles

Another name for the Trumpeter's Muscle

buccinator

The vertical slightly curved furrow in the soft tissue of the cheek

bucco-facial sulcus

Another name for the Levator Labii Superioris Alaeque Nasi

common elevator

Which facial profile is least common?

concave / infantine / retrousse

What is the most common facial profile?

convex

The prominent vertical folds found on the neck.

cords of the neck

The insertion point of the temporalis muscle

coronoid process of mandible

The Transverse interciliary sulci are formed or accentuated by this muscle

corrugator / frowning muscle

The facial markings which are formed or enhanced by the action of the Orbicularis Occuli

creates the optic facial sulci

Another name for Optic Facial Sulci

crow's feet

convex

curved evenly; resembling a segment of the outer edge of a sphere

Describe the Incisive fossa.

depression found immediately below the 4 front teeth

Another name for the Quadratus Muscle

depressor labii inferiorus

The quadrilateral muscle that approaches the lower lip from below and attaches between the middle of the mouth and the angle of the mouth

depressor labii inferious / quadratus

Shallow depressions found in the soft tissue of the cheeks and/or chin

dimples

nasal bones

directly inferior to the glabella and forming a dome over the superior portion of the nasal cavity

Digastricus

double-bellied muscle which lies below the body of the mandible and draws the hyoid bone superiorly

What is the physiological function of the occipito-frontalis muscle?

draws the scalp posteriorly and raises the eyebrows

What facial markings are enhanced or formed by the Levator Angulis Oris?

emphasizes the presence of the nasolabial fold and the angulus oris eminence

Another name for the occipitofrontalis muscle

epicranius

Describe the location of the Sternocleidomastoid muscle

extends from the lobe of the ear to the clavicle

form

external shape; a mold for casting; produce a certain shape; to constitute existing elements

Acquired facial markings

facial markings that develop during one's lifetime, primarily as a result of repetitious use of certain muscles

An elongated prominence of flesh which abuts convexly against an adjacent surface

fold / eminence

The large opening of the occitipal bone is called the:

foramen magnum

The general shape of the skull can be observed from what three viewpoints?

frontal, side/profile, crown

Another name for a wrinkle

furrow

Describe the Superior Palpebral Sulcus

furrow located at the attached margin of the upper eyelid

Common transverse sulcus

furrow of the upper eyelid found approximately 1/8" - 1/4" from the line of eye closure

Describe the interciliary sulci.

furrows between the eyebrows (Gordon Ramsay's truly pissed off face)

Which transverse frontal sulci appear deeper than the others?

furrows nearest the eyebrows

Linear sulci

furrows of the eyelid which are short and broken, extending horizontally on the palpebrae themselves and which may fan from both the medial and lateral corners of the eyes.

Transverse frontal sulci

furrows which cross the forehead.

The singular elevation of the frontal bone found just superior to the bridge of the nose and medial from the superciliary arches

glabella

An elongated depression in a surface plane is known as a(n)

groove

three-quarter view

in reference to a photograph, a view which reveals the fullness of the cheeks.

The furrow of the lower (attached) border of the lower eyelid

inferior palpebral sulcrus

The movable portion of a muscle which is attached to muscle or skin

insertion

What is the purpose of the foramen magnum on a living body?

it is the opening through which the spinal cord passes from the brain into the spine

What is the purpose of the foramen magnum on a decapitated body?

it is used to reattach the head, by attaching one end of a rod to the bones of the spinal column and the other end through the foramen magnum

Asymmetry

lack of symmetry, balance, or proportion

Occipitofrontalis (Epicranius)

large singular muscle which covers the top and sides of the cranium. It draws the scalp posteriorly and inferiorly and raises the eyebrows

The muscle of the mouth which is located in the region of the upper canine teeth

levator anguli oris

The intermediate head of the Quadratus Labii Superioris and raises the upper lip

levator labii superioris

The muscle that raises the upper eyelid

levator palpebrae superioris

occipital bone

lowest part of the back and base of the cranium, forming a cradle for the brain

Do males or females have more definite facial markings due to muscle action?

males

The muscle which forms the exterior planes of the cheek

masseter

What are the 2 main muscles of mastication?

masseter and temporalis

The thick quadrilateral muscle located on the side of the face near the angle of the mandible

masseter?

The bones which form the upper jaw

maxillae

Differentiate between the terms medial and lateral.

medial - toward the midline lateral - away from midline

The bony prominence of the chin

mental eminence

The muscle that wrinkles the chin

mentalis

superior

more elevated in place or position; higher; upper; anatomically towards the head.

Palpebra

movable, protective fold that opens and closes, covering the eye (eyelid)

Mentalis

muscle situated over the prominence of chin which elevates and protrudes the inferior lip and wrinkles the skin over the chin

The two bones which lie directly inferior to the Glabella

nasal bones

The small angular area formed by the junction of the posterior margin of the nasal wing and the superior end of the Nasolabial fold.

nasal sulcus

The prominence of the anterior part of the cheek.

nasolabial fold

The furrow which may develop along the medial margin of nasolabial fold

nasolabial sulcus

buccal depression

natural, shallow concavities of the cheeks which extend obliquely downward from the medial or lateral margins of the cheekbones

medial

nearer to the midline; opposite of lateral

Describe the mouth and nose of an oblong geometric head shape.

nose is long with prominent tip; mouth tends to narrow

The large muscle that covers the top and sides of the head

occipitofrontalis / epicranius

vertical concave profile

one in which the forehead and the eyebrows project equally to a vertical line and the chin protrudes more than the upper lip

vertical convex profile

one in which the forehead and the eyebrows project equally to a vertical line and the chin recedes from the projection of the upper lip

vertical profile / balanced

one in which the forehead, upper lip, and chin project equally to an imaginary vertical line

zygomatic arch depression

one of the lesser concavities of the face located on the lateral portion of the cheek inferior to the zygomatic arch

Those facial markings that radiate, laterally from the outer canthus of the eye, onto the side of the face

optic facial sulci (crow's feet)

The broad sphincter muscle that surrounds the eye

orbicularis oculi

The portion of a muscle which is attached to a fixed point

origin

What is the general shape of the skull?

oval

What is the most common geometric head form?

oval

frontal eminences

paired, rounded, unmargined prominences of the frontal bone found approximately one inch beneath the normal hairline

horizontal

parallel to the plane of the horizon; transverse plane

vertical

perpendicular to the plane of the horizon; balanced.

The vertical groove on the central plan of the upper integumentary lip

philtrum

The broad, flat superficial muscle of the neck

platysma

he transverse wrinkles of the neck are enhanced or caused by this muscle

platysma

The greatly dipping furrows across the neck

platysmal sulci

The long, thin muscle which extends vertically from the lower part of the nasal bone to the skin of the lower part of the forehead

procerus / concentrating muscle

mandibular prognathism

protrusion of the inferior jaw

maxillary prognathism

protrusion of the superior jaw

post-embalming treatments

restorative procedures performed after the embalming operation.

pre-embalming treatments

restorative procedures performed before the embalming operation.

median plane / midsagittal plane

situated or placed in the middle of the body dividing it into right and left halves

lines of the temple

slightly raised, curved ridges located at the boundary between the forehead and the temple region; marks the lateral border of the forehead

inclination

slope; deviation from the horizontal or vertical; oblique

The type of muscle which encircles a natural orifice of the body

sphincter

Orbicularis oculi

sphincter muscle that closes the eyelids; compresses the lacrimal sacs (tear production.)

Orbicularis oris (Puckering Muscle)

sphincter muscle which encircles the mouth and closes and puckers the lips.

protrusion

state or condition of being thrust forward or projecting

The mastoid process is used for the attachment of what muscle?

sternocleidomastoid (SCM)

The widest part of the neck is formed between these muscles

sternocleidomastoid muscles

The furrow or groove which lies at the juncture of the base of the chin and the submandibular area.

submental sulcus

The bony landmarks of the frontal bone that lie on the lower part of the forehead and just above the medial ends of the eyebrows

supercilliary arches

Which palpebral sulcus is wider (Inferior Palpebral Sulcus or Superior Palpebral Sulcus)?

superior

The widest measurement of the anterior plane of the face is measured between these bone

temporal process

The broad, fan shaped muscle that radiates above the ear

temporalis

Nasolabial fold

the anterior fold of the cheek which descends laterally along the upper lip from the wing of the nose.

frontal bone

the anterior third of the cranium, forming the forehead and the anterior portion of the roof of the skull

coronoid process

the anterior, non-articulating process of the ramus of the mandible which serves as the insertion for the temporalis muscle.

bridge of the nose

the arched portion of the nose which is supported by the nasal bones

origin

the attachment of a muscle which moves least (or not at all) when the muscle contracts; the beginning

parietal bones

the bones that form the roof and part of the sides of the skull

orbital cavity / eye socket

the bony region containing the eyeball

Nasolabial sulcus

the furrow lying medial and adjacent to the nasolabial fold.

Inferior palpebral sulcus

the furrow of the lower attached border of the inferior palpebra.

Superior palpebral sulcus

the furrow of the superior border of the superior palpebra.

Optic facial sulci / crow's feet

the furrows radiating from the lateral corner of the eye

Angulus oris sulcus

the groove at each end of the line of mouth closure

body of the mandible

the horizontal portion of the lower jaw

supercilliary arches

the inferior part of the forehead just superior to the median ends of the eyebrows

Submental sulcus

the junction of the base of the chin and the submandibular area, may appear as a furrow.

The widest measurement of the cranium is between what structures?

the parietal eminences

Where does bone ossification begin in the body?

the parietal eminences

cranium

the part of the skull which encloses the brain

Buccinator (Trumpeter's muscle)

the principle muscle of the cheek which compresses the cheeks and forms the lateral wall of the mouth

Mastication

the process of chewing

internal tissue building

the process of restoring natural fullness to the facial features during the embalming process using techniques such as a higher rate of flow, intermittent drainage, intravascular pressure, and humectant chemicals.

zygomatic arch / process

the processes on the temporal and zygomatic bones; determines the widest part of the face

nuchal line of occipital bone

the projection of bone at the posterior/inferior portion of the skull

parietal eminence

the rounded peak of the external convexity of the parietal bones; determines the widest part of the cranium

Physiognomy

the study of the structure and surface markings of the face and features

crown / vertex

the topmost part of the head

Bucco-facial sulcus

the vertical furrow of the cheek.

Philtrum

the vertical groove located medially on the superior integumentary lip

Interciliary sulci / frowning sulci

the vertical or transverse furrows between the eyebrows

squama

the vertical surface of the temporal bone

Platysma

thin layer of muscle covering anterior aspect of neck.

Natural facial markings

those markings which may be present at birth or are hereditary. If they are not present at birth, they are not acquired throughout the life of the individual.

Platysmal sulci / double chin

transverse, dipping furrows of the anterior neck

what is the least common geometric head form?

triangular

Anatomical position

used as a reference in describing body parts to one another, in which the body is erect, feet together, palms forward, and thumbs are pointed away

Which interciliary sulci are known to be the concentrating sulci? Which are known to be the frowning sulci?

vertical - frowning horizontal - concentrating

septum

vertical cartilage dividing nasal cavity into two chambers, responsible for asymmetry of the nose

labial sulci / smoker's lines

vertical furrows of the lips extending from within the mucous membranes into the integumentary lip

The widest part of the face is measured between these structures

zygomatic arches

Mandibular sulcus

furrow beneath the mandible which rises vertically on the cheek.

dental prognathism / buck teeth

Oblique insertion of the teeth; front teeth protrude

What are the two forms of dimples?

Rounded or vertical in form

What general shape does the philtrum resemble?

irregular parenthesis is the norm (also triangular, inverted triangular, and parallel)

If the eyes will not properly close, this muscle may (though should NOT) be severed to aid in eye closure

levator pelebrae superioris

What facial marking is enhanced by the Depressor Anguli Oris Muscle?

lines around mouth?

Masseter

major muscle of mastication

major restoration

one requiring a long period of time, are extensive, require advanced technical skill, and expressed written consent to perform.

minor restoration

one requiring minimum effort, skill, or time to complete.

posterior

position of direction toward the back

occipital protuberance

prominence at the center of the external surface of the occipital bone

The narrow, superficial muscle which runs across the cheek and attaches at the angle of the mouth

risorius

What is an alternate term for the infantine geometric head shape?

round

How many geometric head shapes are there?

seven

Dimples

shallow depressions located on the cheek or chin

oblique

slanting or inclined, neither perpendicular nor horizontal

What is an alternate term for the square geometric head shape?

strong

complexion

the color and texture of the skin, especially that of the face

temporal cavity

the concave surface of the head overlying the temporal bone

incisive fossa

the depression between the mental eminence and the inferior incisor teeth.

width

the dimension of an object measured across from side to side.

columna nasi

the fleshy termination of the nasal septum at the base of the nose; located between the nostrils; the most inferior part of the mass of the nose

Labiomental sulcus

the junction of the lower integumentary lip and the superior border of the chin, which may appear as a furrow. The deeper the incisive fossa, the more prominent the labiomental sulcus.

Directionally, how are facial markings related to the muscle that creates them?

the lie perpendicular to the muscles that make them

norm

the most common characteristics of each feature; typical, common, average

insertion

the movable portion of a muscle which is attached to muscle or skin

Levator anguli oris

the muscle located in the area of the canine teeth which elevates the angle of the mouth.

Depressor anguli oris (Triangularis)

the muscle located inferior to the lateral portion of the mouth

Depressor labii inferiorus (Quadratus)

the muscle located inferior to the medial portion of the mouth

Risorius

the narrow superficial band of muscle which pulls the angle of the mouth laterally

foramen magnum

the opening in the occipital bone through which the spinal cord passes

external auditory meatus

the opening or passageway of the ear

nasal cavity

the orifice in the bony face bounded by the margins of the nasal bones and the maxilla

contour

the outline or surface form

mastoid process

the rounded projection on the inferior portion of the temporal bones just posterior to the lobe of the ear

Oblique palpebral sulcus

the shallow, curving groove below the inner corner of the eyelids.

Nasal spine of the maxilla

the sharp, bony projection located medially at the inferior margin of the nasal cavity.

profile / silhouette

the side view of the human head

Angulus oris eminence

the small convex prominence lateral to the end of the line of mouth closure.

mandibular fossa

the small oval depression on the zygomatic process of the temporal bone into which the condyle of the mandible articulates, just anterior to the external auditory meatus.

buccal cavity

the space between the lips and the gums and teeth; the vestibule of the oral cavity

supra-orbital margin

the superior rim of the eye socket

Bilateral

two sides

Describe the location of the Depressor Anguli Oris.

under the corners of the mouth

ramus

vertical portion of the mandible

Cords of the neck

vertical prominences of the neck

The bony structure which projects anteriorly from the squama of the temporal bone

zygomatic arch

The muscle located lateral of the Quadratus Labii Superioris that descends obliquely from the posterior portion of the cheekbone to the angle of mouth

zygomaticus major

The lateral head of the Quadratus Labii Superioris

zygomaticus minor

Another name for the Depressor Anguli Oris Muscle

Triangularis Muscle

According to the lesson notes, what are three examples of co-embalming restorative art treatments?

- internal tissue building - sustaining feature alignment - swelling control

lateral

a direction or projection which is away from the midline; to the side

Concave-convex profile

a facial profile in which the forehead protrudes beyond the eyebrows while the chin recedes from the plane of the upper lip

Infranasal prognathism

a form of prognathism in which the base of the nasal cavity protrudes abnormally

depression

a hollow or shallow concave area in a surface

Describe the Quadratus Labii Superioris muscle.

a large 3 bellied muscle extending from the upper cheeckbone/eyesocket to the upper lip

The medial head of the Quadratus Labii Superioris

- levator labii superioris

concave

exhibiting a depressed or hollow surface; a concavity

cartilage

A specialized type of dense connective tissue; attached to the ends of bones and forming parts of structures, such as the nasal septum and the framework of the ear.

Concave-vertical profile

facial profile in which the forehead protrudes beyond the eyebrows while the upper lip and chin project equally to an imaginary vertical line

What, if any, is the difference between the male and female skull after puberty?

female skulls are generall smaller

Vertical lines

fine linear tracings extending vertically on both upper and lower mucous membranes

temporal bone

form the inferior portion of the sides and base of the cranium; inferior to the parietal bones and anterior to the occipital bone