A&P CH 14

Typically, an interruption in blood flow for ___-___ minutes impairs neuronal function, and total deprivation of oxygen for about ____ minutes causes permanent injury. Because virtually no ______ is stored in the brain, the supply of it also must be continuous. If blood entering the brain has a low level of it, ____ ____, ___, ____, and ___ of ____ may occur. People with diabetes must be vigilant about their blood sugar levels because these levels can drop quickly, leading to diabetic shock, which is characterized by seizure, coma, and possibly death.

1-2, 4, glucose, mental confusion, dizziness, convulsions, loss of conciousness

the cranial dura has ___ layers as opposed to ___ in the spine

2, 1

______ nerves. Nuclei in the pons provide motor impulses that control eyeball movement via the ____ nerves.

Abducens, abducens

_____ nerves. These fibers are actually part of the vagus (X) nerves. Nuclei in the medulla are the origin for nerve impulses that control swallowing via the --- nerves.

Accessory, vagus

___ ____ contain axons that conduct nerve impulses between gyri in the same hemisphere.

Association tracts

____ are one type of neuroglia; the processes of many of them press up against the capillaries and secrete chemicals that maintain the _____ characteristics of the ____ ____. A few water-soluble substances, such as ______, cross the BBB by ___ ____. Other substances, such as _____, ____, and most _____, cross the BBB very slowly. Still other substances—_____ and most ____ _____—do not pass at all from the blood into brain tissue.

Astrocytes, permeability, tight junctions, glucose, active transport, creatinine, urea, ions, proteins, antibiotic drugs

metencephalon

Becomes the pons, cerebellum, and upper part of fourth ventricle

___ ____ ___ innervate skeletal muscles that develop from the pharyngeal (branchial) arches. These neurons leave the brain through the mixed cranial nerves and the accessory nerve.

Branchial motor axons

Posterior to the brain stem is the _____.

Cerebellum

_ __ is a clear, colorless liquid composed primarily of water that protects the brain and spinal cord from chemical and physical injuries. It also carries small amounts of ____ , ____, and other needed chemicals from the blood to neurons and neuroglia. CSF continuously circulates through cavities in the brain and spinal cord and around the brain and spinal cord in the _____ space.

Cerebrospinal fluid, oxygen, glucose, subarachnoid

Supported on the diencephalon and brain stem is the _____, the largest part of the brain.

Cerebrum

____ ___ contain axons that conduct nerve impulses from gyri in one cerebral hemisphere to corresponding gyri in the other cerebral hemisphere.

Commissural tracts,

telencephalon

Develops into the cerebrum and lateral ventricles

_____ nerves. Nuclei in the pons receive sensory impulses for taste and provide motor impulses to regulate secretion of ____ and ____ and contraction of muscles of ____ expression via the ____ nerves.

Facial, saliva, tears, facial, facial

Diencephalon

Forms the thalamus, hypothalamus, epithalamus, and third ventricle

mesencephalon

Gives rise to midbrain and aqueduct of the midbrain

______ nerves. Nuclei in the medulla relay sensory and motor impulses related to taste, swallowing, and salivation via the ____ nerves.

Glossopharyngeal, glossopharyngeal

____ nerves. Nuclei in the medulla are the origin for nerve impulses that control tongue movements during speech and swallowing via the ____ nerves.

Hypoglossal, hypoglossal

The anterior nucleus receives input from the _____ and sends output to the _____ system. It functions in emotions and memory.

hypothalamus, limbic

A bridge of gray matter called the ____ ___ joins the right and left halves of the thalamus in about 70% of human brains. A vertical Y-shaped sheet of white matter called the ____ ___ ___ divides the gray matter of the right and left sides of the ____. It consists of _____ axons that enter and leave the various thalamic nuclei. Axons that connect the thalamus and cerebral cortex pass through the ____ ____, a thick band of white matter lateral to the thalamus.

interthalamic adhesion, internal medullary lamina, thalamus, myelinated, internal capsule

The CSF formed in the choroid plexuses of each lateral ventricle flows into the third ventricle through two narrow, oval openings, the _____ ____ . More CSF is added by the choroid plexus in the roof of the third ventricle. The fluid then flows through the _____ of the midbrain, which passes through the midbrain, into the fourth ventricle. The choroid plexus of the fourth ventricle contributes more fluid. CSF enters the _____ space through three openings in the roof of the fourth ventricle: a single ____ aperture and paired ____ apertures, one on each side. CSF then circulates in the central canal of the spinal cord and in the ____ space around the surface of the brain and spinal cord.

interventricular foramina, aqueduct, subarachnoid, median, lateral, subarachnoid

There is one ____ ventricle in each hemisphere of the cerebrum. Anteriorly, the _____ ventricles are separated by a thin membrane, the ___ ____ The third ventricle is a narrow slitlike cavity along the midline superior to the ____ and between the right and left halves of the ____. The fourth ventricle lies between the brain stem and the ____.

lateral, lateral, septum pellucidum, hypothalamus, thalamus, cerebellum

Nuclei in the _____ group receive input from the ____ system, ____ ____, and ___ ___ and send output to the cerebral cortex. The ___ ____ nucleus functions in the expression of emotions. The ____ ____ nucleus and _____ nucleus help integrate sensory information.

lateral, limbic, superior colliculi, cerebral cortex, lateral dorsal, lateral posterior, pulvinar

Wernicke's area, a broad region in the __ ___ and ____ lobes, interprets the meaning of speech by recognizing spoken words. It is active as you translate words into thoughts. The regions in the ____ hemisphere that correspond to Broca's and Wernicke's areas in the ____ hemisphere also contribute to verbal communication by adding emotional content, such as anger or joy, to spoken words. Unlike those who have CVAs in Broca's area, people who suffer strokes in Wernicke's area can still speak, but cannot arrange words in a coherent fashion.

left temporal, parietal, right, left,

The so-called ____ ___ is a rim of cerebral cortex on the medial surface of each hemisphere. It includes the ____ ___, which lies above the corpus callosum, and the ____ ___, which is in the temporal lobe below. The hippocampus is a portion of the ____ ___ that extends into the floor of the lateral ventricle.

limbic lobe, cingulate gyrus, corpus callosum, parahippocampal gyrus, parahippocampal gyrus

Encircling the upper part of the brain stem and the corpus callosum is a ring of structures on the inner border of the cerebrum and floor of the diencephalon that constitutes the ____ ____

limbic system

The medial nuclei receive input from the _____ system and ___ ___ and send output to the ___ ____. They function in emotions, learning, memory, and cognition

limbic, basal nuclei, cerebral cortex

Together with the ____ system, the hypothalamus participates in expressions of ___, ___, pain, and ___, and the behavioral patterns related to sexual arousal.

limbic, rage, aggression, pain, pleasure

The corticospinal tracts control voluntary movements of the ___ and ____. Just superior to the junction of the medulla with the spinal cord, 90% of the axons in the left pyramid cross to the right side, and 90% of the axons in the right pyramid cross to the left side. This crossing is called the _____ of ____ and explains why each side of the brain controls voluntary movements on the opposite side of the body.

limbs, trunk, decussation of pyamids

Each cerebral hemisphere can be further subdivided into several ____.

lobes

Axons of parasympathetic motor neurons in the vagus nerve originate in nuclei of the medulla and supply the ____, ___, ____ ___, ______ ____, _____, ____, _____, ____ ___, and most of the ___ ____. Parasympathetic motor axons initiate smooth muscle contractions in the gastrointestinal tract to aid motility and stimulate secretion by digestive glands; activate smooth muscle to constrict respiratory passageways; and decrease heart rate.

lungs, heart, gi tract, smooth muscle, esophagus, stomach, gallbladder, small intestine, large intestive

The ___ ___ of the hypothalamus are two round masses close to the midline near the cerebral peduncles.

mammillary bodies

The ____ ____, adjacent to the midbrain, is the most posterior part of the hypothalamus. It includes the mammillary bodies and posterior hypothalamic nuclei The ___ ____ are two small, rounded projections that serve as relay stations for reflexes related to the sense of ___.

mammillary region, mammillary bodies, smell

The brain stem is continuous with the spinal cord and consists of the ______ ____, _____, and ____.

medulla oblongata, pons, midbrain

The diencephalon forms a central core of brain tissue just superior to the ____. It is almost completely surrounded by the ___ ____ and contains numerous nuclei involved in a wide variety of sensory and motor processing between higher and lower brain centers. The diencephalon extends from the brain stem to the ____ and surrounds the _____ ventricle; it includes the ____, _____, and ____. Projecting from the hypothalamus is the ____, or pituitary gland. Portions of the diencephalon in the wall of the third ventricle are called ______ organs. The optic tracts carrying neurons from the retina enter the diencephalon.

midbrain, cerebral hemispheres, cerebrum, third, thalamus, hypothalamus, epithalamus, hypophysis, circumventricular

The _____ or _______ extends from the pons to the diencephalon and is about 2.5 cm long.

midbrain, mesencephalon

The ____ ____ forms a thin band adjacent to the third ventricle and has a presumed function in memory and olfaction.

midline nucleus,

Five cranial nerves are classified as ____ ___ because they contain only axons of motor neurons as they leave the brain stem. The cell bodies of these lie in nuclei within the brain.

motor nerves

The neural crest is a mass of tissue between the ______ ____ and the skin ______. It differentiates and eventually forms the posterior (dorsal) root ganglia of spinal nerves, ____ ____, ganglia of cranial nerves, ____ ____, ganglia of the autonomic nervous system, ____ _____, and ______.

neural tube, ectoderm, spinal nerves, cranial nerves, adrenal medulla, meninges

The medulla also contains several ____. Some of these control vital body functions. Examples of them in the medulla that regulate vital activities include the _____ ____ and the ___ ____ ___.

nuclei, cardiovascular center, cardiovascular center

CSF is a medium for minor exchange of ___ and ____ ___ between the blood and adjacent nervous tissue.

nutrients, waste products

The limbic system plays a primary role in a range of emotions, including pain, pleasure, docility, affection, and anger. It also is involved in _____ and _____.

olfaction, memory,

Just lateral to each pyramid is an oval-shaped swelling called an ____. Within it is the inferior ___ ___, which receives input from the _____ ____, red nucleus of the ____, and ___ ___.

olive, olivary nucleus, cerebral cortex, midbrain, spinal cord,

Lipid-soluble substances, such as __, __ ___, ___, and most ___ agents, are able to access brain tissue freely. _____, certain ____, and ____ can cause a breakdown of the blood-brain barrier.

oxygen, carbon dioxide, alcohol, anesthetic, trauma, toxins, inflammation

In an adult, the brain represents only 2% of total body weight, but it consumes about 20% of the ____ and _____ used by the body, even when you are resting. Neurons synthesize ATP almost exclusively from glucose via reactions that use oxygen. When the activity of neurons and neuroglia increases in a particular region of the brain, ____ ___ to that area also increases. Even a brief slowing of brain ____ ____ may cause disorientation or a lack of consciousness, such as when you stand up too quickly after sitting for a long period of time.

oxygen, glucose, blood flow, blood flow

The ____ of the CSF affects pulmonary ventilation and cerebral blood flow, which is important in main- taining homeostatic controls for brain tissue. CSF also serves as a transport system for ___ ____ secreted by hypothalamic neurons that act at remote sites in the brain.

pH, polypeptide hormones,

The inferior branch of the oculomotor nerve also supplies _______ motor axons to intrinsic eyeball muscles, which consist of smooth muscle. They include the ____ ____ of the eyeball and the circular muscles of the iris. Parasympathetic impulses propagate from a nucleus in the midbrain to the ____ ___, a synaptic relay center for the two motor neurons of the parasympathetic nervous system. From the ciliary ganglion, parasympathetic motor axons extend to the ciliary muscle, which adjusts the lens for near vision (accommodation). Other parasympathetic motor axons stimulate the circular muscles of the iris to contract when bright light stimulates the eye, causing a decrease in the size of the pupil (constriction).

parasympathetic, ciliary muscle, ciliary ganglion

The parieto-occipital sulcus separates the ____ lobe from the ____ lobe. A fifth part of the cerebrum, the ____, cannot be seen at the surface of the brain because it lies within the lateral cerebral sulcus, deep to the parietal, frontal, and temporal lobes

parietal, occipital, insula

The two dural layers are called the ______ layer (which is external) and the ______ layer (which is internal). The dural layers around the brain are fused together except where they separate to enclose the ___ _____ ____ that drain venous blood from the brain and deliver it into the internal jugular veins.

periosteal, meningeal, dural venous sinuses

In the cerebral cortex, primary sensory areas receive sensory information that has been relayed from ___ ___ ___ through lower regions of the brain. Sensory association areas often are adjacent to the primary areas. They usually receive input both from the primary areas and from other brain regions. Sensory association areas integrate sensory experiences to generate meaningful patterns of recognition and awareness. For example, a person with damage in the primary visual area would be blind in at least part of his visual field, but a person with damage to a visual association area might see normally yet be unable to recognize ordinary objects such as a lamp or a toothbrush just by looking at them.

peripheral sensory receptors,

The hypothalamus produces several hormones and has two types of important connections with the _____ gland, an endocrine gland located inferior to the hypothalamus.

pituitary

Although the brain is almost symmetrical on its right and left sides, subtle anatomical differences between the two hemispheres exist. For example, in about two-thirds of the population, the ____ ___, a region of the temporal lobe that includes Wernicke's area, is 50% larger on the left side than on the right side. This asymmetry appears in the human fetus at about 30 weeks gestation. Physiological differences also exist; although the two hemispheres share performance of many functions, each hemisphere also specializes in performing certain unique functions. This functional asymmetry is termed ___ ___.

planum temporale, hemispheric lateralization

The ____ lies directly superior to the medulla and anterior to the cerebellum and is about 2.5 cm. Like the medulla, it consists of both ___ and ___. As its name implies, it is a bridge that connects parts of the brain with one another. These connections are provided by bundles of ____. Some ____ of the pons connect the right and left sides of the cerebellum. Others are part of ascending ___ tracts and descending ___ tracts

pons, nuclei, tracts, axons, axons, sensory, motor

The primary gustatory area, located at the base of the ____ ____ superior to the ____ ____ ___ in the parietal cortex, receives impulses for taste and is involved in gustatory perception and taste discrimination.

postcentral gyrus, lateral cerebral sulcus

Another major gyrus, the _____ gyrus, which is located immediately posterior to the _____ sulcus, contains the primary _____ area of the cerebral cortex. The ____ cerebral sulcus (fissure) separates the ____ lobe from the _____ lobe.

postcentral, central, somatosensory, lateral, frontal, temporal

The tracts of the posterior columns and the axons of the medial lemniscus are collectively known as the ____ ____-____ ___ ____.

posterior column-medial lemniscus pathway.

The pineal gland is about the size of a small pea and protrudes from the ____ ___ of the ___ ____ The pineal gland is part of the ____ system be- cause it secretes the hormone melatonin. As more melatonin is liberated during darkness than in light, this hormone is thought to promote sleepiness. When taken orally, melatonin also appears to contribute to the setting of the body's biological clock by inducing sleep and helping the body to adjust to jet lag.

posterior midline, third ventricle, endocrine,

The primary visual area, located at the ____ tip of the _____ ___ mainly on the medial surface, receives visual information and is involved in visual perception.

posterior, occipital lobe,

Aside from the coordination of skilled movements, the cerebellum is the main brain region that regulates _____ and _____. These aspects of cerebellar function make possible all skilled muscular activities, from catching a baseball to dancing to speaking.

posture, balance

The primary motor area is located in the ____ ____ of the frontal lobe. As is true for the primary _____ area, a "map" of the entire body is present in the primary motor area: Each region within the area controls voluntary contractions of specific muscles or groups of muscles. Electrical stimulation of any point in the primary motor area causes contraction of specific ____ ____ fibers on the opposite side of the body. Different muscles are represented unequally in the primary motor area. More cortical area is devoted to those muscles involved in skilled, complex, or delicate movement. For instance, the cortical region devoted to muscles that move the fingers is much larger than the region for muscles that move the toes. This distorted muscle map of the body is called the ____ ___.

precentral gyrus, somatosensory, skeletal muscle, motor homunculus

The frontal eye field area in the frontal cortex is sometimes included in the _____ area. It controls voluntary scanning movements of the eyes—like those you just used in reading this sentence.

premotor

The ____ ___ anterior to the supraoptic region is usually considered part of the hypothalamus because it participates with the hypothalamus in regulating certain autonomic activities. It contains the ____ and ____ preoptic nuclei

preoptic region, medial, lateral

The orbitofrontal cortex receives sensory impulses from the ___ ___ area. This area allows you to identify odors and to discriminate among different odors. During olfactory processing, the orbitofrontal cortex of the ____ hemisphere exhibits greater activity than the corresponding region in the ___ hemisphere.

primary olfactory, right, left

A "map" of the entire body is present in the ____ ___ area: Each point within the area receives impulses from a specific part of the body. The size of the ____ area receiving impulses from a particular part of the body depends on the number of receptors present there rather than on the size of the body part. For example, a larger region of the _____ area receives impulses from the lips and fingertips than from the thorax or hip. This distorted ___ ___ map of the body is known as the ___ ___

primary somatosensory, cortical, somatosensory, somatic sensory, sensory homunculus

The ___ ___ area is located directly ____ to the central sulcus of each cerebral hemisphere in the postcentral gyrus of each parietal lobe. It extends from the ___ ___ sulcus, along the lateral surface of the parietal lobe to the longitudinal fissure, and then along the medial surface of the parietal lobe within the longitudinal fissure. The primary somatosensory area receives nerve impulses for ___. __, __, __, __, __, and ___ and is involved in the perception of these somatic sensations.

primary somatosensory, posterior, lateral cerebral, touch, pressure, vibration, itch, tickle, temperature, preprioception

The ______, or forebrain, gives rise to the ___ and ___, and the ____, or hindbrain, develops into the ____ and ____.

prosencephalon, telencephalon, diencephalon, rhombencephalon, metencephalon, myelencephalon

Axons of the parasympathetic motor neurons run in branches of the facial nerve and end in two ganglia: the ________ ganglion and the _____ ganglion. From synaptic relays in the two ganglia, postganglionic parasympathetic motor axons extend to _____ glands, ___ glands, palatine glands, and saliva-producing glands.

pterygopalatine, submandibular, lacrimal, nasal, palatine

The presence of ___ ___ between the cerebellum and association areas of the cerebral cortex suggests that the cerebellum may also have nonmotor functions such as _____ and _____ processing. This view is supported by imaging studies using MRI and PET. Studies also suggest that the cerebellum may play a role in processing _____ information.

reciprocal connections, cognition, language, sensory

First, hypothalamic hormones known as _____ hormones and _____ hormones are released into capillary networks in the median eminence. The bloodstream carries these hormones directly to the anterior lobe of the _____, where they stimulate or inhibit secretion of anterior pituitary hormones. Second, ____ extend from the _____ and ____ nuclei through the infundibulum into the posterior lobe of the pituitary. The cell bodies of these neurons make one of two hormones. Their axons transport the hormones to the posterior _____, where they are released.

releasing, inhibiting, pituitary, axons, paraventricular, supraoptic, pituitary

The ____ ___ surrounds the lateral aspect of the thalamus, next to the internal capsule. This nucleus monitors, filters, and integrates activities of other thalamic nuclei.

reticular nucleus

The RAS also prevents ___ ___ by filtering out insignificant information so that it does not reach consciousness. Inactivation of the RAS produces sleep, a state of partial consciousness from which an individual can be aroused. Damage to the RAS, on the other hand, results in coma, a state of unconsciousness from which an individual cannot be aroused. In the lightest stages of coma, brain stem and spinal cord reflexes persist, but in the deepest states even those reflexes are lost, and if respiratory and cardiovascular controls are lost, the patient dies. Drugs such as ____ affect the RAS by helping to induce sleep, and general anesthetics turn off consciousness via the RAS. The descending portion of the RAS has connections to the cerebellum and spinal cord and helps regulate muscle tone, the slight degree of involuntary contraction in normal resting skeletal muscles. This portion of the RAS also assists in the regulation of heart rate, blood pressure, and respiratory rate.

sensory overload, melatonin,

Specific types of ____, ____, and _____ signals are processed in certain regions of the cerebral cortex. Generally, ____ areas receive sensory information and are involved in perception, the conscious awareness of a sensation; ___ areas control the execution of _____ movements; and association areas deal with more complex integrative functions such as ____, ____. ____, ___, ___, ____ traits, ____

sensory, motor, integrative, sensory, sensory, motor, voluntary, memory, emotions, reasoning, will, judgement, personality, intelligence

The ____ ___ are located within the septal area formed by the regions under the corpus callosum and the paraterminal gyrus

septal nuclei

The ophthalmic nerve, the ____ branch, passes into the orbit via the ____ ____ ___. The maxillary nerve is intermediate in size between the ophthalmic and mandibular nerves and passes through the ____ ____. The mandibular nerve, the ____ branch, passes through the ___ ___.

smallest, superior orbital fissure, foramen rotundum, largest, foramen ovale

The _____ ____ area is just posterior to and receives input from the ___ ___ area, as well as from the _____ and other parts of the brain. This area permits you to determine the exact shape and texture of an object by feeling it, to determine the orientation of one object with respect to another as they are felt, and to sense the relationship of one body part to another. Another role of the ____ ___ area is the storage of memories of past somatic sensory experiences, enabling you to compare current sensations with previous experiences.

somatosensory association, primary somatosensory, thalamus, somatosensory association

The common integrative area is bordered by ____, ____, and ____ association areas. It receives nerve impulses from these areas and from the primary ____ area, the primary ____ area, the ____, and parts of the brain stem. This area integrates sensory interpretations from the association areas and impulses from other areas, allowing the formation of thoughts based on a variety of sensory inputs. It then transmits signals to other parts of the brain for the appropriate response to the sensory signals it has interpreted.

somatosensory, visual, auditory, gustatory, olfactory, thalamus

Three cranial nerves carry axons of sensory neurons and thus are called ___ ____ ___. These nerves are unique to the head and are associated with the special senses of ___, ____, and ____. The cell bodies of most sensory neurons are located in ganglia outside the brain.

special sensory nerves, smelling, seeing, hearing

The inferior cerebellar peduncles consist of (1) axons of the ________ ____ that carry sensory information into the cerebellum from _____ in the trunk and limbs; (2) ____ from the ___ ___ of the inner ear and from the ___ ____ of the medulla and pons that carry sensory information into the cerebellum from proprioceptors in the head; (3) ___ from the ____ ___ ___ of the medulla that enter the cerebellum and regulate the activity of cerebellar neurons; (4)___ that extend from the cerebellum to the ____ _____ of the medulla and pons; and (5) ____ that extend from the cerebellum to the ____ ____

spinocerebellar tracts, proprioceptors, axons, vestibular apparatus, vestibular nuclei, axons, inferior olivary nucleus, axons, vestibular nuclei, axons, reticular formation

The accessory nerve conveys motor impulses to the _____ and ____ muscles to coordinate head movements. Sensory axons in the accessory nerve, which originate from proprioceptors in the ______ and ____ muscles, begin their course toward the brain in the accessory nerve, but eventually leave the nerve to join nerves of the ___ ___. From the cervical plexus they enter the spinal cord via the posterior roots of cervical spinal nerves; their cell bodies are located in the posterior root ganglia of those nerves. In the spinal cord the axons ascend to nuclei in the _____ _____.

sternocleidomastoid, trapezius, sternocleidomastoid, trapezius, cervical plexus, medulla oblongata

Axons of branchial motor neurons arise from a nucleus in the pons and exit the _____ ___ to innervate middle ear, facial, scalp, and neck muscles. Nerve impulses propagating along these axons cause contraction of the muscles of facial expression plus the ___ ___, the posterior belly of the ____ ___, and the _____ ____. The facial nerve innervates more named muscles than any other nerve in the body.

stylomastoid foramen, stylohyoid muscle, digastric muscle, stapedius muscle

The midbrain contains several other nuclei, including the left and right ____ ___, which are large and darkly pigmented.

substantia nigra

Neurons that release dopamine, extending from the ___ ___ to the ___ ___, help control subconscious muscle activities. Loss of these neurons is associated with ___ ___. Also present are the left and right red nuclei, which look reddish due to their rich blood supply and an iron-containing pigment in their neuronal cell bodies. ____ from the cerebellum and cerebral cortex form synapses in the red nuclei, which help control _____ movements.

substantia nigra, basal nuclei, Parkinson's disease, Axons, muscular

Nearby structures that are functionally linked to the basal nuclei are the ____ ____ of the midbrain and the ____ ____ of the dincephalon. Axons from the ____ ____ terminate in the caudate nucleus and putamen. The ____ ____ interconnect with the globus pallidus.

substantia nigra, subthalamic nuclei, substantia nigra, subthalamic nuclei

The ___ ____ ____ contain axons that extend from the cerebellum to the red nuclei of the midbrain and to several nuclei of the thalamus. The ___ ____ ___ are the largest peduncles; their axons carry impulses for voluntary movements from the pontine nuclei into the cerebellum.

superior cerebellar peduncles, middle cerebellar peduncles,

The medulla oblongata, or more simply the medulla, is continuous with the ____ part of the spinal cord; it forms the inferior part of the brain stem. The medulla begins at the ____ ____ and extends to the inferior border of the ____, a distance of about 3 cm

superior, foramen magnum, pons

The ______ nucleus of the hypothalamus serves as the body's internal biological clock because it establishes ____ rhythms. This nucleus receives input from the eyes and sends output to other hypothalamic nuclei, the reticular formation, and the ____ gland.

suprachiasmatic, circadian, pineal

The ____ ____ lies superior to the optic chiasm and contains the _____ nucleus, ____ nucleus, ____ ____ nucleus, and _____ nucleus.

supraoptic region, paraventricular, supraoptic, anterior hypothalamic, suprachiasmatic

The ventral region of the pons forms a large ___ ___ ___ consisting of scattered gray centers called the ___ ____. Entering and exiting these nuclei are numerous ___ ___ tracts, each of which provides a connection between the cortex of a cerebral hemisphere and that of the opposite hemisphere of the cerebellum. This complex circuitry plays an essential role in coordinating and maximizing the efficiency of voluntary ____ output throughout the body. The dorsal region of the pons is more like the other regions of the brain stem, the medulla and midbrain. It contains ascending and descending tracts along with the nuclei of ___ ___.

synaptic relay station, pontine nuclei, white matter, motor, cranial nerves

The posterior part of the midbrain, called the _____, contains four rounded elevations. The two superior elevations, nuclei known as the superior _____, serve as reflex centers for certain ____ activities. Through neural circuits from the retina of the eye to the superior colliculi to the extrinsic eye muscles, visual stimuli elicit eye movements for tracking moving images and scanning stationary images. The superior ____ are also responsible for reflexes that govern movements of the ___, ____, and ____ in response to visual stimuli. The two inferior elevations, the inferior _____, are part of the ____ pathway, relaying impulses from the receptors for hearing in the inner ear to the brain. These two nuclei are also reflex centers for the ____ reflex, sudden movements of the ____, ___, and ____ that occur when you are surprised by a loud noise such as a gunshot.

tectum, colliculi, visual, colliculi, head, eyes, trunk, colliculi, auditory, startle, head, eyes, trunk

The primary auditory area, located in the superior part of the ____ ___ near the ___ ____ __, receives information for sound and is involved in auditory perception.

temporal lobe, lateral cerebral sulcus

The primary olfactory area, located in the ____ ___ on the ___ ___, receives impulses for smell and is involved in olfactory perception.

temporal lobe, medial aspect

Superior to the brain stem is the diencephalon, which consists of the _____, _____, and ______.

thalamus, hypothalamus, epithalamus

The aqueduct of the midbrain passes through the midbrain, connecting the ___ ___ above with the ___ ___ below. Like the medulla and the pons, the midbrain contains both ___ and ____

third ventricle, fourth ventricle, nuclei, tracts

Development of the nervous system begins in the ____ week of gestation with a thickening of the _____ called the neural plate. The plate folds inward and forms a longitudinal groove, the ____ groove. The raised edges of the plate are called ____ folds. As development continues, the folds increase in height and meet to form a tube called the _____ tube.

third, ectoderm, neural, neural, neural

The blood-brain barrier (BBB) consists mainly of ____ ___ that seal together the _____ cells of brain blood capillaries and a thick ____ ____ that surrounds the capillaries.

tight junctions, endothelial, basement membrane,

Nuclei associated with sensations of ___, ___, ___, and conscious ____ are located in the posterior part of the medulla. These nuclei are the right and left ____ nucleus and ____ nucleus.

touch, pressure, vibration, proprioception, gracile, cuneate

A deep groove known as the ____ ____, along with the ____ ____, which supports the posterior part of the cerebrum, separates the cerebellum from the cerebrum

transverse fissure, tentorium cerebelli

The ___ ___, the widest part of the hypothalamus, includes the _____ nucleus, _____ nucleus, and arcuate nucleus, plus the stalklike ______, which connects the pituitary gland to the hypothalamus. The median eminence is a slightly raised region that encircles the _____

tuberal region, dorsomedial, ventromedial, infundibulum, infundibulum

The cranial accessory nerve actually is part of the ____ nerve.

vagus

Five nuclei are part of the ventral group. The ____ ____ nucleus receives input from the basal nuclei and sends output to motor areas of the cerebral cortex; it plays a role in movement control. The ___ ____ nucleus receives input from the cerebellum and basal nuclei and sends output to motor areas of the cerebral cortex; it also plays a role in movement control. The ____ ____ nucleus relays impulses for somatic sensations such as touch, pressure, vibration, itch, tickle, temperature, pain, and proprioception from the face and body to the cerebral cortex. The _____ ____ nucleus relays visual impulses for sight from the retina to the primary visual area of the cerebral cortex. The ____ ____ nucleus relays auditory impulses for hearing from the ear to the primary auditory area of the cerebral cortex.

ventral anterior, ventral lateral, ventral posterior, lateral geniculate, medial geniculate

The pons has two major structural components: a _____ region and a _____ region.

ventral, dorsal

In superior or inferior views, the shape of the cerebellum resembles a butterfly. The central constricted area is the ____, and the lateral "wings" or lobes are the ____ ____. Each hemisphere consists of lobes separated by deep and distinct fissures. The ____ lobe and ______ lobe govern subconscious aspects of skeletal muscle movements. The _____ lobe on the inferior surface contributes to equilibrium and balance.

vermis, cerebellar hemispheres, anterior, posterior, flocculonodular

The _____ ____ area, located in the ___ ___, receives sensory impulses from the primary visual area and the thalamus. It relates present and past visual experiences and is essential for recognizing and evaluating what is seen.

visual association, occipital lobe,

The facial recognition area receives nerve impulses from the ____ ____ area. This area stores information about faces, and it allows you to recognize people by their faces. The facial recognition area in the ___ hemisphere is usually more dominant than the corresponding region in the ___ hemisphere.

visual association, right, left

Three layers of cells differentiate from the wall that encloses the neural tube. The outer or marginal layer cells develop into the ____ ____ of the nervous system. The middle or mantle layer cells develop into the____ ____. The cells of the inner or ____ layer eventually form the lining of the central canal of the spinal cord and ventricles of the brain.

white matter, gray matter, ependymal

The medulla's ___ ___ contains all ____ (ascending) tracts and ____ (descending) tracts that extend between the spinal cord and other parts of the brain. Some of the white matter forms bulges on the ____ aspect of the medulla. These protrusions, called the ____, are formed by the large ___ tracts that pass from the cerebrum to the spinal cord.

white matter, sensory, motor, anterior, pyramids, corticospinal

The Olfactory (_) nerve is entirely sensory; it contains axons that conduct nerve impulses for olfaction, the sense of smell. The olfactory epithelium occupies the superior part of the ___ ___, covering the inferior surface of the ____ ___ and extending down along the ___ ____ ___. The olfactory receptors within the olfactory epithelium are ____ neurons. Each has a single odor-sensitive, knob-shaped ____ projecting from one side of the cell body and an _____ axon extending from the other side. Bundles of axons of olfactory receptors extend through about 20 olfactory foramina in the cribriform plate of the ethmoid bone on each side of the nose. These 40 or so bundles of axons collectively form the right and left olfactory nerves. Olfactory nerves end in the brain in paired masses of ____ ____ called the ___ ___, two extensions of the brain that rest on the cribriform plate. Within the olfactory bulbs, the axon terminals of olfactory receptors form synapses with the dendrites and cell bodies of the next neurons in the olfactory pathway. The axons of these neurons make up the olfactory tracts, which extend posteriorly from the olfactory bulbs. Axons in the olfactory tracts end in the primary olfactory area in the temporal lobe of the cerebral cortex.

I, nasal cavity, cribriform plate, superior nasal concha, bipolar, dendrite, unmyelinated, gray matter, olfactory bulbs

The optic (___) nerve is entirely sensory; it contains axons that conduct nerve impulses for vision. In the retina, ___ and ___ initiate visual signals and relay them to ____ cells, which transmit the signals to ganglion cells. Axons of all ganglion cells in the retina of each eye join to form an optic nerve, which passes through the ___ ___. About 10 mm posterior to the eyeball, the two optic nerves merge to form the ____ ___. Within it, axons from the medial half of each eye cross to the opposite side; axons from the lateral half remain on the same side. Posterior to it, the regrouped axons, some from each eye, form the ___ ___. Most axons in these end in the lateral geniculate nucleus of the thalamus. There they synapse with neurons whose axons extend to the primary visual area in the occipital lobe of the cerebral cortex. A few axons pass through the ___ ____ nucleus and then extend to the ___ ___ of the midbrain and to motor nuclei of the brain stem where they synapse with motor neurons that control the extrinsic and intrinsic eye muscles.

II, rods, cones, bipolar, optic foramen, optic chiasm, optic tracts, lateral geniculate, superior colliculi,

The oculomotor (___) nerve has its motor nucleus in the ____ part of the midbrain. The oculomotor nerve extends anteriorly and divides into superior and inferior branches, both of which pass through the ____ ____ ___ into the orbit. Axons in the superior branch innervate the ____ ___ and the ___ ___ ___. Axons in the inferior branch supply the ___ ___, ___ ___, and ___ ___ muscles—all extrinsic eyeball muscles. These somatic motor neurons control movements of the eyeball and upper eyelid.

III, anterior, superior orbital fissure, superior rectus, levator palpebrae superioris, medial rectus, inferior rectus, inferior oblique

The trochlear (___) nerve is the ____ of the 12 cranial nerves and is the only one that arises from the ____ aspect of the brain stem. The somatic motor neurons originate in a nucleus in the midbrain (trochlear nucleus), and axons from the nucleus cross to the opposite side as they exit the brain on its posterior aspect. The nerve then wraps around the ____ and exits through the ____ ____ ___ into the orbit. These somatic motor axons innervate the superior oblique muscle of the eyeball, another extrinsic eyeball muscle that controls movement of the eyeball.

IV, smallest, posterior, pons, superior orbital fissure,

The glossopharyngeal (___) nerve is a ____ cranial nerve. Sensory axons of the glossopharyngeal nerve arise from (1) ____ ____ on the posterior one-third of the tongue, (2) ______ from some swallowing muscles supplied by the motor portion, (3) _____ (pressure-monitoring receptors) in the carotid sinus that monitor blood pressure, (4) _______ (receptors that monitor blood levels of oxygen and carbon dioxide) in the carotid bodies near the carotid arteries and aortic bodies near the arch of the aorta, and (5) the external ____ to convey touch, pain, and thermal (heat and cold) sensations. The cell bodies of these sensory neurons are located in the superior and inferior ganglia. From the ganglia, sensory axons pass through the _____ ____ and end in the -____.

IX, mixed, taste buds, proprioceptors, baroreceptors, chemoreceptors, ear, jugular foramen, medulla

______ nuclei lie within the internal ____ ____ and make connections with the reticular formation, cerebellum, basal nuclei, and wide areas of the cerebral cortex. They function in _____ and _____ of _____ and ____ information.

Intralaminar, medullary lamina, arousal, integration, sensory, motor

Receives somatic sensory signals from, and controls muscles on, right side of body. reasoning numerical and scientific skills ability to understand sign language spoken and written language Persons with damage in this hemisphere often exhibit aphasia.

Left

____ nerves. Nuclei in the midbrain provide motor impulses that control movements of the eyeball, while accessory oculomotor nuclei provide motor control to the smooth muscles that regulate constriction of the pupil and changes in shape of the lens via the ____ nerves.

Oculomotor, oculomotor

The ____ ___ are flattened bodies of the olfactory pathway that rest on the cribriform plate.

Olfactory bulbs

____ ____ contain axons that conduct nerve impulses from the _____ to lower parts of the CNS or from lower parts of the CNS to the _____. An example is the internal capsule, a thick band of white matter that contains both ascending and descending axons

Projection tracts, cerebrum, cerebrum,

The ascending portion of the reticular formation is called the ___ ___ ___, which consists of sensory axons that project to the ____ ___, both directly and through the _____.

Reticular activating system, cerebral cortex, thalamus,

Generating mental images to compare spatial relationships. Identifying and discriminating among odors. Patients with damage in this hemisphere regions that correspond to Broca's and Wernicke's areas in the left hemisphere speak in a monotonous voice, having lost the ability to impart emotional inflection to what they say. Generating emotional content of language. Recognition of faces and emotional content of facial expressions. Space and pattern perception. Musical and artistic awareness. Receives somatic sensory signals from, and controls muscles on, left side of body.

Right

____ ___ arrive mainly in the posterior half of both cerebral hemispheres, in regions behind the ___ ___.

Sensory impulses, central sulci

____ ____ ___ innervate skeletal muscles that develop from head somites. These neurons exit the brain through five motor cranial nerves. Motor axons that innervate smooth muscle, cardiac muscle, and glands are called autonomic motor axons and are part of the _____ division.

Somatic motor axons, parasympathetic

_______ which measures about 3 cm (1.2 in.) in length and makes up 80% of the diencephalon, consists of paired oval masses of ____ matter organized into nuclei with interspersed tracts of ____ matter.

Thalamus, gray, white

______ nerves. Nuclei in the pons receive sensory impulses for somatic sensations from the head and face and provide motor impulses that govern chewing via the ____ nerves.

Trigeminal, trigeminal

____ nerves. Nuclei in the midbrain provide motor impulses that control movements of the eyeball via the ____ nerves.

Trochlear, trochlear

The trigeminal (__) nerve is a _____ cranial nerve and the _____ of the cranial nerves. The trigeminal nerve emerges from two roots on the anterolateral surface of the ____. The large sensory root has a swelling called the trigeminal ganglion, which is located in a fossa on the inner surface of the petrous portion of the temporal bone. The ganglion contains ____ ___ of most of the primary sensory neurons. Neurons of the smaller motor root originate in a nucleus in the ___.

V, mixed, largest, pons, cell bodies, pons

Neurons of the abducens (___) nerve originate from a nucleus in the ___. Somatic motor axons extend from the nucleus to the ____ ____ muscle of the eyeball, an extrinsic eye-ball muscle, through the superior orbital fissure of the orbit. The abducens nerve is so named because nerve impulses cause ____ (lateral rotation) of the eyeball.

VI, pons, lateral rectus, abduction

The facial (___) nerve is a ___ cranial nerve. Its sensory axons extend from the taste buds of the anterior two-thirds of the tongue, which enter the ___ ___ to join the ____ ____. From here the sensory axons pass to the geniculate ganglion, a cluster of cell bodies of sensory neurons of the facial nerve within the temporal bone, and ends in the pons. From the pons, axons extend to the _____, and then to the gustatory areas of the cerebral cortex. The sensory portion of the facial nerve also contains axons from skin in the ear canal that relay touch, pain, and thermal sensations. Additionally, proprioceptors from muscles of the face and scalp relay information through their cell bodies in a nucleus in the ____.

VII, mixed, temporal bone, facial nerve, thalamus, midbrain

The vestibulocochlear (____) nerve was formerly known as the acoustic or auditory nerve. It is a sensory cranial nerve and has two branches, the _____ branch and the ______ branch. The ______ branch carries impulses for equilibrium and the ______ branch carries impulses for hearing.

VIII, vestibular, cochlear, vestibular, cochlear

_____ nerves. Nuclei in the medulla receive sensory impulses from and provide motor impulses to the ___ and ____ and many thoracic and abdominal viscera via the ____ nerves.

Vagus, pharynx, larynx, vagus

_____ nerves: Several nuclei in the medulla receive sensory input from and provide motor output to the cochlea of the internal ear via the _____ nerves. These nerves convey impulses related to hearing.

Vestibulocochlear, vestibulocochlear

________ nerves. Nuclei in the pons receive sensory impulses from and provide motor impulses to the vestibular apparatus via the _____ nerves. These nerves convey impulses related to balance and equilibrium.

Vestibulocochlear, vestibulocochlear

Many sensory stimuli can activate the ascending portion of the RAS. Among these are ____ and _____ stimuli; ___ activities; stimuli from ___, ___, and _____ receptors; and receptors in our ____ and ____ that keep us aware of the position of our body parts.

Visual, auditory, mental, pain, touch, pleassure, limbs, head

The vagus (__) nerve is a ___ cranial nerve that is distributed from the head and neck into the thorax and abdomen. The nerve derives its name from its wide distribution. In the neck, it lies medial and posterior to the _____ ____ ___ and ___ ____ ___.

X, mixed, internal jugular vein, common carotid artery

The accessory (__) nerve is a ___ ____ ___ nerve. Historically it has been divided into two parts, a _____ accessory nerve and a ____ accessory nerve.

XI, branchial motor cranial, cranial, spinal

The hypoglossal (___) nerve is a _____ cranial nerve. The somatic motor axons originate in a nucleus in the ____ ____, exit it on its anterior surface, and pass through the hypoglossal canal to supply the muscles of the _____. These axons conduct nerve impulses for ____ and ____. The sensory axons do not return to the brain in the hypoglossal nerve. Instead, sensory axons that originate from proprioceptors in the tongue muscles begin their course toward the brain in the hypoglossal nerve but leave the nerve to join ____ ____ nerves and end in the ____ _____, again entering the central nervous system via posterior roots of cervical spinal nerves.

XII, motor, medulla oblongata, tongue, speech, swallowing, cervical spinal, medulla oblongata

The ______ is composed of several groups of neurons located close to the tail of the caudate nucleus.

amygdala

The "old" spinal accessory nerve is the accessory nerve we discuss. Its motor axons arise in the ___ ___ ___ of the first five segments of the cervical portion of the spinal cord. The axons from the segments exit the spinal cord laterally and come together, ascend through the ____ _____, and then exit through the ____ ____ along with the vagus and glossopharyngeal nerves.

anterior gray horn, foramen magnum, jugular foramen

Two nuclei of the thalamus, the ____ nucleus and the ____ nucleus, participate in limbic circuits

anterior, medial

The premotor area is a motor association area that is immediately _____ to the primary motor area. Neurons in this area communicate with the primary motor cortex, the sensory association areas in the ___ ___, the ____ ___, and the ___. The premotor area deals with learned motor activities of a complex and sequential nature. It generates nerve impulses that cause specific groups of muscles to contract in a specific sequence, as when you write your name. The premotor area also serves as a memory bank for such movements.

anterior, parietal lobe, basal nuclei, thalamus

CSF is gradually reabsorbed into the blood through ___ ___, fingerlike extensions of the ___ ___ that project into the dural venous sinuses, especially the superior sagittal sinus. Normally, CSF is reabsorbed as rapidly as it is formed by the ___ ___, at a rate of about 20 mL/hr. Because the rates of formation and reabsorption are the same, the pressure of CSF normally is constant. For the same reason, the volume of CSF remains constant.

arachnoid villi, arachnoid mater, choroid plexuses,

Another function of the RAS is to help maintain ____ and _____

attention, alertness

The ____ ___ area, located ___ and ___ to the primary auditory area in the ___ ___, allows you to recognize a particular sound as speech, music, or noise.

auditory association, inferior, posterior, temporal cortex

The hypothalamus also functions as the body's thermostat, which senses body temperature so that it is maintained at a desired setpoint. If the temperature of blood flowing through the hypothalamus is above normal, the hypothalamus directs the _____ nervous system to stimulate activities that promote heat loss. When blood temperature is below normal, by contrast, the hypothalamus generates impulses that promote heat production and retention.

autonomic

The hypothalamus controls and integrates activities of the _____ nervous system, which regulates contraction of ____ muscle and ____ muscle and the secretions of many _____. Axons extend from the hypothalamus to parasympathetic and sympathetic nuclei in the brain stem and spinal cord. Through the _NS, the hypothalamus is a major regulator of visceral activities, including regulation of ___ ___, movement of ___ through the ___ ___, and contraction of the ____ ___.

autonomic, smooth, cardiac, glands, A, heart rate, food, GI tract, urinary bladder

Deep within each cerebral hemisphere are three nuclei that are collectively termed the ____ ___.

basal nuclei

The adult brain consists of four major parts: ___ ___, ___, _____, and ___.

brain stem, cerebellum, diencephalon, and cerebrum

The ___ ____ ___, which run briefly with the accessory nerve, arise from nuclei in the ___ ____ and supply muscles of the pharynx, larynx, and soft palate that are used in swallowing, vocalization, and coughing. Historically these motor neurons have been called the cranial accessory nerve, but these fibers actually belong to the vagus (X) nerve.

branchial motor neurons, medulla oblongata,

Blood flows to the brain mainly via the internal ___ and ___ arteries; the dural venous sinuses drain into the internal ___ ___ to return blood from the head to the heart

carotid, vertebral, jugular veins

The superficial layer of the cerebellum, called the ____ ____, consists of gray matter in a series of slender, parallel folds called ____. Deep to the gray matter are tracts of white matter called ____ ___ that resemble branches of a tree. Even deeper, within the white matter, are the ___ ____, regions of gray matter that give rise to axons carrying impulses from the cerebellum to other brain centers.

cerebellar cortex, folia, arbor vitae, cerebellar nuclei

Three paired ___ ____ attach the cerebellum to the brain stem. These bundles of ___ ___ consist of axons that conduct impulses between the cerebellum and other parts of the brain.

cerebellar peduncles, white matter

Neurons of the inferior olivary nucleus extend their axons into the ____, where they regulate the activity of ____ neurons. By influencing this neuron activity, the inferior olivary nucleus provides instructions that the ____ uses to make adjustments to muscle activity as you learn new motor skills.

cerebellum, cerebellar, cerebellum

The _____, second only to the _____ in size, occupies the inferior and posterior aspects of the cranial cavity. It has a highly folded surface that greatly increases the surface area of its ___ ____ ____ __, allowing for a greater number of neurons. It accounts for about a ___ of the brain mass yet contains nearly ____ of the neurons in the brain. It is ____ to the medulla and pons and _____ to the posterior portion of the cerebrum.

cerebellum, cerebrum, outer gray matter cortex, tenth, half, posterior, inferior,

The thalamus is the major relay station for most sensory impulses that reach the primary sensory areas of the -___ ____ from the ___ ___ and ___ ___. In addition, the thalamus contributes to motor functions by transmitting information from the ____ and __ __ to the primary motor area of the ____ ___. The thalamus also relays nerve impulses between different areas of the _____ and plays a role in the maintenance of consciousness.

cerebral cortex, spinal cord, brain stem, cerebellum, basal nuclei, cerebral cortex, cerebrum

The prefrontal cortex is an extensive area in the anterior portion of the frontal lobe that is well developed in primates, especially humans. This area has numerous connections with other areas of the ____ ___, ____, ____, ___ ___, and ____. The prefrontal cortex is concerned with the makeup of a person's personality, intellect, complex learning abilities, recall of information, initiative, judgment, foresight, reasoning, conscience, intuition, mood, planning for the future, and development of abstract ideas. A person with bilateral damage to the prefrontal cortices typically becomes rude, inconsiderate, incapable of accepting advice, moody, inattentive, less creative, unable to plan for the future, and incapable of anticipating the consequences of rash or reckless words or behavior.

cerebral cortex, thalamus, hypothalamus, limbic system, cerebellum

The anterior part of the midbrain contains paired bundles of axons known as the ____ ___. They consist of axons of the _____, _____, and _____ tracts, which conduct nerve impulses from motor areas in the cerebral cortex to the spinal cord, medulla, and pons, respectively.

cerebral peduncles, corticospinal, corticobulbar, corticopontine

The _____ is the "seat of intelligence." It provides us with the ability to read, write, and speak; to make calculations and compose music; and to remember the past, plan for the future, and imagine things that have never existed before. It consists of an outer _____ ____, an internal region of ___ ____ ___, and ____ ____ nuclei deep within the ___ ___.

cerebrum, cerebral cortex, cerebral white matter, gray matter, white matter

The majority of CSF production is from the ___ ____, networks of blood capillaries in the walls of the ventricles. Ependymal cells joined by ____ ____ cover the capillaries of the ___ ___. Selected substances from the blood plasma, which are filtered from the capillaries, are secreted by the _____ cells to produce the cerebrospinal fluid. This secretory capacity is bidirectional and accounts for continuous production of CSF and transport of metabolites from the nervous tissue back to the blood.

choroid plexuses, tight junctions, choroid plexuses, ependymal,

Parts of the diencephalon, called ______ ____ because they lie in the wall of the third ventricle, can monitor chemical changes in the blood because they lack a blood-brain barrier. They include part of the _____, the ____ gland, the ______ gland, and a few other nearby structures. Functionally, these regions coordinate homeostatic activities of the endocrine and nervous systems, such as the regulation of ___ ___, ___ balance, ____, and ____. They are also thought to be the sites of entry into the brain of HIV, the virus that causes AIDS. Once in the brain, HIV may cause dementia (irreversible deterioration of mental state) and other neurological disorders.

circumventricular organs, hypothalamus, pineal, pituitary, blood pressure, fluid, hunger, thirst

The _____ is a thin sheet of gray matter situated lateral to the _____. It is considered by some to be a subdivision of the ___ ___. The function of it in humans has not been clearly defined, but it may be involved in visual attention.

claustrum, putamen, basal nuclei,

Perhaps the most important function of the RAS is _____, a state of wakefulness in which an individual is fully alert, aware, and oriented. Visual and auditory stimuli and mental activities can stimulate the RAS to help maintain it. The RAS is also active during _____, or awakening from sleep.

consciousness, arousal

Three important groups of commissural tracts are the ____ ___, ____ ___, and ____ ____

corpus callosum, anterior commissure, posterior commissure

The ___ ___ lies between the hippocampus and parahippocampal gyrus.

dentate gyrus

The brain and spinal cord develop from the _____ ____ tube. The anterior part of the neural tube expands, along with the associated neural ____ ___. Constrictions in this expanded tube soon appear, creating three regions called primary brain vesicles: _____, _____, and _____. Both the _____ and ______ subdivide further, forming secondary brain vesicles.

ectodermal neural, crest tissue, prosencephalon, mesencephalon, rhombencephalon, prosencephalon, rhombencephalon

Because of the tight junctions between ____ cells, materials entering CSF from choroid capillaries cannot leak between these cells; instead, they must pass through the _____ cells. This _____-_____ ___ ____ permits certain substances to enter the CSF but excludes others, protecting the brain and spinal cord from potentially harmful blood-borne substances. In contrast to the blood-brain barrier, which is formed mainly by tight junctions of brain capillary endothelial cells, this barrier is formed by _____ _____ of ____ ____.

ependymal, ependymal, blood-cerebrospinal fluid barrier, tight junctions, ependymal cells

There is no _____ space around the brain. Blood vessels that enter brain tissue pass along the surface of the brain, and as they penetrate inward, they are sheathed by a loose-fitting sleeve of ___ ____.

epidural, pia mater

The _____, a small region superior and posterior to the thalamus, consists of the _____ gland and ____ nuclei.

epithalamus, pineal, habenular

Sensory axons in the vagus nerve arise from the skin of the ___ ____ for touch, pain, and thermal sensations; a few taste buds in the _____ and _____; and ______ in muscles of the neck and throat. Also, sensory axons come from ______ in the carotid sinus and _____ in the carotid and aortic bodies. The majority of sensory neurons come from visceral sensory receptors in most organs of the thoracic and abdominal cavities that convey sensations (such as hunger, fullness, and discomfort) from these organs. The sensory neurons have cell bodies in the superior and inferior ganglia and then pass through the jugular foramen to end in the medulla and pons.

external ear, epiglottis, pharynx, proprioceptors, baroreceptors, chemoreceptors

Three extensions of the dura mater separate parts of the brain: (1) The ____ ____ separates the two hemispheres (sides) of the cerebrum. (2) The ___ ____ separates the two hemispheres of the cerebellum. (3) The ____ ___ separates the cerebrum from the cerebellum.

falx cerebri, falx cerebelli, tentorium cerebelli

The primary function of the cerebellum is to evaluate how well movements initiated by motor areas in the cerebrum are actually being carried out. When movements initiated by the cerebral m tor areas are not being carried out correctly, the cerebellum detects the discrepancies. It then sends _____ ____ to motor areas of the ___ ____, via its connections to the _____. The feedback signals help correct the errors, smooth the movements, and coordinate complex sequences of ___ ____ contractions.

feedback signals, cerebral cortex, thalamus, skeletal muscle,

The hypothalamus regulates food intake. It contains a ____ ____, which promotes eating, and a ____ ____, which causes a sensation of fullness and cessation of eating. The hypothalamus also contains a ___ ___. When certain cells in the hypothalamus are stimulated by rising osmotic pressure of the ___ ___, they cause the sensation of thirst. The intake of water by drinking restores the osmotic pressure to normal, removing the stimulation and relieving the thirst.

feeding center, satiety center, thirst center, extracellular fluid,

myelencephalon

forms the medulla oblongata and the lower part of the fourth ventricle

The ____, ___ ___, ____ ___, ____ ___ bundle, and _____ tract are linked by bundles of interconnecting myelinated axons.

fornix, stria terminalis, stria medullaris, medial forebrain, mammillothalamic

Broca's speech area is located in the ___ ___ close to the ___ ____ ___. Speaking and understanding language are complex activities that involve several sensory, association, and motor areas of the cortex. In about 97% of the population, these language areas are localized in the ___ hemisphere. The planning and production of speech occur in the ____ ____ lobe in most people. From Broca's speech area, nerve impulses pass to the premotor regions that control the muscles of the larynx, pharynx, and mouth. The impulses from the premotor area result in specific, coordinated muscle contractions. Simultaneously, impulses propagate from Broca's speech area to the ___ ____ __. From here, impulses also control the breathing muscles to regulate the proper flow of air past the vocal cords. The coordinated contractions of your speech and breathing muscles enable you to speak your thoughts.

frontal lobe, lateral cerebral sulcus, left, left frontal, primary motor area

The central sulcus separates the ____ lobe from the _____ lobe. A major gyrus, the ____ gyrus—located immediately anterior to the central sulcus— contains the primary motor area of the cerebral cortex.

frontal, parietal, precentral,

The lobes are named after the bones that cover them: ___, ___, ___, and ____ lobes.

frontal, parietal, temporal, occipital

Two of the basal nuclei lie side by side, just lateral to the thalamus. They are the ____ ____, which is closer to the thalamus, and the _____, which is closer to the cerebral cortex. Together, they are referred to as the _____ nucleus. The third of the basal nuclei is the _____ ____, which has a large "head" connected to a smaller "tail" by a long comma-shaped "body." Together, they are known as the ___ ___.

globus pallidus, putamen, lentiform, caudate nucleus, corpus striatum,

CSF contains small amounts of ____, ____ , ___ ____, ____, ___ , and ______ it also contains some ___ ____ ___.

glucose, proteins, lactic acid, urea, cations, anions, white blood cells

Ascending sensory axons of the ____ ____ and the ___ ____, which are two tracts in the posterior columns of the spinal cord, form synapses in these nuclei. Postsynaptic neurons then relay the sensory information to the _____ on the opposite side of the brain. The axons ascend to the thalamus in a band of white matter called the ___ ___, which extends through the ___, ___, and _____.

gracile fasciculus, cuneate fasciculus, thalamus, medial lemniscus, medulla, pons, midbrain

The cerebral cortex is a region of _____ ____ that forms the outer rim of the _____. During embryonic development, when brain size increases rapidly, the ____ ____ of the cortex enlarges much faster than the deeper ___ ___. As a result, the cortical region rolls and folds on itself. The folds are called ____ or -___. The deepest grooves between folds are known as _____; the shallower grooves between folds are termed ____. The most prominent one, the ____ ____, separates the cerebrum into right and left halves called cerebral hemispheres. Within the (______ _____) between the cerebral hemispheres is the ____ ____. The cerebral hemispheres are connected internally by the ____ ___, a broad band of white matter containing axons that extend between the hemispheres

gray matter, cerebrum, gray matter, white matter, gyri, convolutions, fissures, sulci, longitudinal fissure, falx cerebri, corpus callosum

In addition to the well-defined nuclei already described, much of the brain stem consists of small clusters of neuronal cell bodies (____ ____) interspersed among small bundles of myelinated axons (____ ____). The broad region where they exhibit a netlike arrangement is known as the ___ ___. It extends from the superior part of the spinal cord, throughout the brain stem, and into the inferior part of the diencephalon. Neurons within the this have both ascending (_____) and descending (___) functions.

gray matter, white matter, reticular formation, sensory, motor

The medulla also contains nuclei that are components of sensory pathways for ___ , __, and ___.

gustation, audition, equilibrium

The _____ nucleus of the medulla is part of the gustatory pathway from the tongue to the brain; it receives ____ input from the taste buds of the tongue. The ____ nuclei of the medulla are part of the auditory pathway from the inner ear to the brain; they receive auditory input from the ____ of the inner ear. The _____ nuclei of the medulla and pons are components of the equilibrium pathway from the inner ear to the brain; they re- ceive sensory information associated with ___ from proprioceptors in the vestibular apparatus of the inner ear

gustatory, gustatory, cochlear, cochlea, vestibular, Equilibrium

The ____ ____ are involved in olfaction, especially emotional responses to odors such as a loved one's cologne or Mom's chocolate chip cookies baking in the oven.

habenular nucle

Besides regulating ____, ___ ____ ___, and the normal _____ rhythm, nuclei in the medulla also control reflexes for ___, ___, ___, ___, and ___

heartbeat, blood vessel diameter, breathing, vomiting, swallowing, sneezing, coughing, hiccuping

Axons from the paraventricular and supraoptic nuclei form the ____ ____, which extends through the infundibulum to the posterior lobe of the pituitary

hypothalamohypophyseal tract