Chapter 13

Front 1

name the major regions of the brain and the distinct structure of each.

Back 1

The major regions of the brain are the cerebrum (composed of fissures, gyri, and sulci), the diencephalon (thalamus and hypothalamus), the cerebellum, and the brain stem (midbrain, pons, and medulla oblongata). Additionally, the brain contains four ventricles and some connecting passageways ( the interventricular foramen and the aquaduct of the midbrain), plus the corpus callosum and the septum pellucidum.

Front 2

Describe the role of the medulla oblongata.

Back 2

The medulla oblongata (the most caudal of the brain regions) relays sensory information to other parts of the brain stem and to the thalamus. It also contains centers that regulate autonomic function, such as heart rate and blood pressure.

Front 3

Compare the corpus callosum to the septum pellucidum.

Back 3

The corpus callosum is a bundle of axons that links the left and right cerebral hemispheres, whereas the septum pellucidum is a partition that separates the two lateral ventricles.

Front 4

From superficial to deep, name the layers that constitute the cranial meninges.

Back 4

The layers of the cranial meninges are the outer dura mater, the middle arachnoid mater, and the inner pia mater.

Front 5

What would happen if the normal circulation of reabsorption of CSF became blocked

Back 5

If the normal movement of CSF were blocked, CSF would continue to be produced at the choroid plexuses in each ventricle, but the fluid would remain there, causing the ventricles to swell-a condition known as hydrocephalus.

Front 6

How would decreased diffusion across the arachnoid granulations affect the volume of cerebrospinal fluid in the ventricles?

Back 6

If diffusion across the arachnoid granulations decreased, the volume of CSF in the ventricles would increase, because less CSF would reenter the bloodstream. The increased pressure within the brain due to accumulated CSF could damage the brain.

Front 7

What is the function of the ascending and descending tracts in the medulla oblongata?

Back 7

The ascending and descending tracts of the white matter in the medulla oblongata link the brain with the spinal cord.

Front 8

Name the medulla oblongata parts that relay somatic sensory information to the thalamus.

Back 8

The nucleus gracilis and nucleus cuneatus are parts of the medulla oblongata that relay somatic sensory information to the thalamus.

Front 9

Describe the pyramids of the medulla oblongata and the result of decussation.

Back 9

The puramids contain tracts of motor fibers that originate at the cerebral cortex; the result of decussation (crossing over) is that each side of the motor cortex controls the opposite side of the body.

Front 10

Identify the components of the cerebellar gray matter.

Back 10

The components of the cerebellar gray matter are the cerebellar cortex and the cerebellar nuclei.

Front 11

Describe the arbor vitae, including its makeup, location, and function.

Back 11

The arbor vitae, which is the white matter of the cerebellum, connects the cerebellar cortex and nuclei with the cerebellar peduncles.

Front 12

Describe ataxia.

Back 12

Ataxia is the failure of muscular coordination that can result from trauma, stroke, or certain drugs, including alcohol.

Front 13

Cranial nerves III to XII arise from which structure?

Back 13

Cranial nerves III to XII arise from the brain stem.

Front 14

Identify the sensory nuclei contained within the corpora quadrigemina.

Back 14

The two pairs of sensory nuclei contained within the corpora quadrigemina are the superior colliculi and inferior colliculi.

Front 15

Which area(s) of the midbrain control reflexive movement of the eyes, head, and neck?

Back 15

The superior colliculi of the midbrain control reflexive movements of the eyes, head, and neck.

Front 16

Name the main components of the diencephalon.

Back 16

The main components of the diencephalon are the epithalamus, thalamus, and hypothalamus.

Front 17

Damage to the lateral geniculate nuclei of the thalami would interfere with what particular function?

Back 17

Damage to the lateral geniculate nuclei would interfere with the flow of visual information and thus affect the sense of sight.

Front 18

Which component of the diencephalon is stimulated by changes in body temperature?

Back 18

The preoptic area of the hypothalamus, a component of the diencephalon, is stimulated by changes in body temperature.

Front 19

List the primary functions of the limbic system.

Back 19

The limbic system establishes emotional states; links the conscious, intellectual functions of the brain stem; and facilitates memory storage and retrieval.

Front 20

Which region of the limbic system is particularly important for the storage and retrieval of long term memories?

Back 20

The hippocampus is important in the storage and retrieval of long-term memories.

Front 21

Damage to the amygdaloid body would interfere with the regulation of which division of the autonomic nervous system.

Back 21

Damage to the amygdaloid body would interfere with the sympathetic ("fight or flight") division of the autonomic nervous system.

Front 22

Define the basal nuclei.

Back 22

The basal nuclei (also known as the basal ganglia) are masses of cerebral gray matter that function in the subconscious control of skeletal muscle activity.

Front 23

Describe the caudate nucleus.

Back 23

The caudate nucleus is one of the basal nuclei involved with the subconscious control of skeletal muscular activity.

Front 24

What clinical signs would you expect to observe in an individual who has damage to the basal nuclei?

Back 24

Damage to the basal nuclei would result in decreased muscle tone and the loss of coordination of learned movement patterns.

Front 25

Identify the lobes of the cerebrum and indicate the basis for their names.

Back 25

The lobes of the cerebrum-the frontal lobe, parietal lobe, occipital lobe, and temporal lobe-are names for the overlying bones of the skull.

Front 26

Describe the insula.

Back 26

The insula is an island of cortex located medial to the lateral sulcus.

Front 27

What effect would damage to the left postcentral gyrus produce?

Back 27

Damage to the left postcentral gyrus would interfere with the awareness of sensory information from the right side of the body.

Front 28

Where is the primary motor cortex located?

Back 28

The primary motor cortex is located in the precentral gyrus of the frontal lobe of the cerebrum.

Front 29

Which senses are affected by damage to the temporal lobes?

Back 29

Damage to the temporal lobes of the cerebrum would interfere with the processing of olfactory (smell) and auditory (sound) sensations.

Front 30

Which brain part has been affected in a stroke victim who is unable to speak?

Back 30

The stroke has damaged the speech center, located in the frontal lobe.

Front 31

Define electroencephalogram (EEG).

Back 31

An electroencephalogram (EEG) is a graph of the electrical activity of the brain.

Front 32

Describe the four wave types associated with an EEG.

Back 32

The four wave types associated with an EEG are alpha waves (characteristic of normal resting adults), beta waves (characteristic of a person who concentrating), theta waves (observed in children and frustrated adults), and delta waves (found in a person who is sleeping deeply of in individuals with certain pathological states).

Front 33

Differentiate between a seizure and epilepsy.

Back 33

A seizure is a temporary cerebral disorder accompanied by abnormal movements, unusual sensations, inappropriate behavior, or some combination of these signs and symptoms. Epilepsy is a clinical condition characterized by seizures.

Front 34

Identify the cranial nerves by name and number.

Back 34

The cranial nerves are the olfactory (I), optic (II), oculomotor (III), trochlear (VI), facial (VII), vestibulocochlear (VIII), glossopharyngeal (IX), vagus (X), accessory (XI), and hypoglossal (XII) nerves.

Front 35

Which cranial nerves have motor functions only?

Back 35

The cranial nerves with motor functions only are the oculomotor (III), trochlear (IV), abducens (VI), accessory (XI), and hypoglossal (XII).

Front 36

Which cranial nerves are mixed nerves?

Back 36

The cranial nerves with mixed functions are the trigeminal (V), facial (VII), glossopharyngeal (IX), and vagus (X) nerves.

Front 37

List the four types of general sensory receptors based on function, and identify the type of stimulus that excites each type.

Back 37

The four types of general sensory receptors (and stimuli that excite them) are nociceptors (pain), thermoreceptors (temperature), mechanoreceptors (physical distortion), and chemoreceptors (chemicals dissolved in body fluids).

Front 38

Describe the three classes of mechanoreceptors.

Back 38

The three classes of mechanoreceptors are tactile receptors which respond to the sense of touch; baroreceptors, which detect changes in pressure; and proprioceptors, which monitor the positions of bones, joints, and muscles.

Front 39

Explain adaptation, and differentiate between peripheral adaptation and central adaptation.

Back 39

Adaptation is a decrease in receptor sensitivity after chronic stimulation. Peripheral adaptation reduces the amount of information from receptors that reaches the central nervous system. In central adaptation, awareness of a stimulus virtually disappears, even though sensory neurons in the CNS remain active.

Front 40

Identify the six types of tactile receptors located in the skin, and describe their sensitivities.

Back 40

The six types of tactie receptors are free nerve endings (are sensitive to touch and pressure), the root hair plexus (monitors distortion of the movement across the body surface), tactile discs and Merkel cells (detect fine touch and pressure), tactile corpuscles (detect fine touch and pressure), lamellated corpuscles (are sensitive to pulsing or vibrating stimuli, such as deep pressure), and Ruffini corpuscles ( are sensitive to pressure and distortion of the skin).

Front 41

Which types of receptors are located only in the dermis?

Back 41

Tactile receptors found only in the dermis are tactile corpuscle, lamellated corpuscles, and Ruffini corpuscles.

Front 42

Which is likely to be more sensitive to continuous deep pressure: a lamellated corpuscle or a Ruffini corpuscle?

Back 42

A Ruffini corpuscle is more sensitive to continuous deep pressure because, unlike a lamelated corpuscle, it undergoes little adaptation.

Front 43

Define sensory homunculus.

Back 43

A sensory homunculus is a functional map of the primary sensory cortex.

Front 44

Which spinal tracts carry action potentials generated by nociceptors?

Back 44

The lateral spinothalamic tracts carry action potentials generated by nociceptors.

Front 45

Which cerebral hemisphere receives impulses conducted by the right fasciculus gracilis of the spinal cord?

Back 45

The left cerebral hemisphere (specifically, the primary sensory cortex in that hemisphere) receives impulses conducted by the right fasciculus gracilis.

Front 46

Define corticospinal tracts.

Back 46

Corticospinal tracts are descending tracts that carry motor commands from the cerebral cortex to the anterior gray horns of the spinal cord.

Front 47

Describe the role of the corticobulbar tracts.

Back 47

The corticobulbar tracts (which are descending tracts) carry information of commands from the cerebral cortex to nuclei and centers in the brain stem.

Front 48

What effect would increased stimulation of the motor neurons of the red nucleus have on muscle tone?

Back 48

Increased stimulation of the motor neurons of the red nucleus would increase stimulation of the skeletal muscles in the upper limbs, thereby increasing their muscle tone.

Front 49

The basic motor patterns related to eating and drinking are controlled by what region of the brain?

Back 49

The basic motor patterns related to eating and drinking are controlled by the hypothalamus.

Front 50

Which brain regions control reflexes in response to visual and auditory stimuli that are experienced while viewing a movie?

Back 50

The thalamus and midbrain control reflexes in response to visual and auditory stimuli experienced while viewing a movie.

Front 51

During a tennis match, you decide how and where to hit the ball. Explain how the motor associations areas are involved.

Back 51

As you decide to hit the ball, the motor association areas receive information from the frontal lobes and then relay that information to the basal nuclei and cerebellum. As the hitting movement begins, the motor association areas send additional information to the primary motor cortex.

Front 52

Define referred pain.

Back 52

Referred pain is a sensation felt in a part of the body other than its actual source.

Front 53

Describe how rabies is contracted.

Back 53

After being bitten by a rabid animal, the rabies virus infects peripheral nerves. Retrograde flow then carries the viral particles into the CNS.

Front 54

Describe amyotrophic lateral sclerosis (ALS).

Back 54

Amyotrophic lateral sclerosis (ALS), commonly called Lou Gehrig disease, is a progressive degeneration of the motor neurons of the CNS, leading to muscle atrophy and eventual paralysis.

Front 55

What special names are given to axons in the white matter of the cerebral hemispheres?

Back 55

The axons in the cerebral white matter are called association fibers, commissural fibers, and projection fibers.

Front 56

What is the function of the longitudinal fasciculi?

Back 56

The longitudinal fasciculi connect the frontal lobe to the other lobes of the same hemisphere.

Front 57

What are fibers carrying information between the brain and spinal cord called, and through which brain regions do they pass?

Back 57

Projection fibers carry information between the cerebral cortex and the spinal cord, in the process passing through the diencephalon, brain stem, and cerebellum.