Brain/Nervous System

Olfaction (smell)

(chemical sense); scent molecules reach the olfactory epithelium deep in the nasal cavity, the scent molecules contact receptor cells at this location, which project to the olfactory bulbs of the brain. from there information travels to the olfactory cortex and the limbic system.

Three points should be kept in mind regarding the cerebral hemispheres:

1. Although selected regions of the cerebral cortex do participate in specific functions, in many cases it is difficult to assign a precise function to a specific region of the cerebral cortex. Considerable overlap and in distinct boundaries permit a single region of the cerebral cortex to exhibit several different functions. Additionally, some aspects of cortical function, such as memory or consciousness, cannot easily be assigned to any single region. 2. As a general rule, both cerebral hemispheres receive their sensory information from, and project motor commands to, the opposite side of the body. The right cerebral hemisphere communicates with the left side of the body, and vice versa. 3. The two cerebral hemispheres appear as anatomical mirror images, but they display some functional differences, termed cerebral lateralization. For example, the regions of the brain that are responsible for controlling speech and understanding verbalization are frequently located in the left cerebral hemisphere. These types of differences primarily affect higher-order functions.

Place cranial nerves in order of numeric name beginning with number I. The 12 pairs of cranial nerves are given numeric names starting with the olfactory nerve that originates from the cerebrum down to hypoglossal nerve which arises from the brain stem. CN I directly enters the cerebrum. CN II directly enters the diencephalon, CN III and IV arise from the midbrain, CN V-VII arise from the pons, and CN VII-XII arise from the medulla oblongata.

1.) Olfactory 2.) Optic 3.) Oculomotor 4.) Trochlear 5.) Trigeminal 6.) Abducens 7.)Facial 8.)Vestibulocochlear 9.)Glossopharyngeal 10.) Vagus 11.)Accessory 12.)Hypoglossal

Choroid plexus

A highly vascular portion of the lining of the ventricles that secretes cerebrospinal fluid.

Brain growth is 95% complete by age five.

Age 5

The effectors of the autonomic nervous system include cardiac muscle, smooth muscle, and glands.

Autonomic

Label the parts of the nervous system. Use each label twice.

Body: central nervous system, peripheral nervous system Chart: central nervous system, peripheral nervous system

Which organs are part of the central nervous system?

Brain and spinal cord

Cranial nerve VIII (Vestibulocochlear) conducts equilibrium and auditory information to the brain.

CN VIII (Vestibulocochlear)

Cranial nerve X (Vagus) innervates structures in the head, neck, and the thoracic and abdominal cavities.

CN X (Vagus)

12 pairs of cranial nerves

CNI (olfactory) smell CNII (Optic) Vision CNIII (Oculomotor) four extrinsic eye muscles CNIV (trochlear) Superior oblique extrinsic eye muscle CNV (Trigeminal) General sesory from anterior scalp, nasal cavity, nasopharnyx, entire face, oral cavity, meninges, tongue CNVI (abducens) lateral rectus extrinsic eye muscle CNVII (facial) controls muscles of facial expression CNVIII (Hearing/Vestibulocochlear) Sense of equilibrium CNIX (glossopharyngeal) general sensory and taste CNX (Vagus) Visceral sensory: heart, lungs, and abdominal CNXI (accessory) Trapezius muscle, sternocleidomastoid muscle CNXII(hypoglossal) Intrinsic and extrinsic tongue muscles/monitor blood pressure

The brain and the spinal cord make up the Central Nervous System.

CNS

Cranial nerve VII (facial) innervates muscles for facial expression, tear production and most salivary glands

CNVII (Facial)

Cranial nerve XI (Accessory) innervates the trapezius, sternocleidomastoid, and pharynx muscles.

CNXI (Accessory)

Cranial nerve label describing its function:

Carry impulses from taste buds: Facial n. Glossopharyngeal n. And Vagus n. Innervates Extrinsic Muscles of the Eye: Oculomotor n. Trochlear n. Abductees n. Contain Parasympathetic Fibers: Facial n. Glossopharyngeal n. Vagus n. Oculomotor n. Contain Only Sensory Neurons: Optic n. Olfactory n. Vestibulocochlear n.

Spinal Cord Order

Cervical, Thoracic, lumbar, sacral, coccygeal, cauda equina

The cribriform plate of the ethmoid bone is a bony plate with foramina (holes) that transmit the olfactory nerve (CN I) fibers.

Cribiform Plate of Ethmoid—Identify which olfactory nerve fibers are transmitted.

Drag each of the Given signs and symptoms of nerve damage to the proper position to indicate the nerve most likely affected by the condition

Dysfunction allows medical professionals to diagnose which nerve or associated structures have been damaged.

Effectors

Effectors are outside the nervous system and are controlled or modified by nerve impulses.

The muscles and glands whose activities are controlled by nervous activity are classified as effectors

Effectors: Muscles and glands change function based on nervous input, carrying out the effect of nervous stimulation.

The spinal cord extends from the level of the foramen magnum to the level of the first lumbar vertebra.

Foramen magnum; first lumbar vertebra

The Hypoglossal nerve is responsible for movement of the tongue.

Hypoglossal

Hypoglossal nerve (CN XII) leaves the cranium through the Hypoglossal canal, and travels inferior to the mandible and to the interior surface of the tongue. In addition to its sensory function of general sensation and taste to the posterior one-third of the tongue, the Glossopharyngeal nerve also conducts visceral Afferent sensory impulses from the carotid sinus to monitor blood pressure and carotid body to monitor blood oxygen and carbon dioxide.

Hypoglossal Nerve CNXII

Place cranial nerves in order of numeric name beginning with number I

I. Olfactory II. Optic III. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VII. Facial VIII. Vestibulocochlear IX. Glossopharyngeal X. Vagus XI. Accessory XII. Hypoglossal

cerebral cortex

Is the surface layer of gray matter of the cerebrum and that the cerebral nuclei are the internal, deep gray matter within the cerebrum. The cerebral gray matter, like all gray matter, functions as centers of integration and processing.

Hypoglossal Nerve (XII) at the carotid sinus.

Monitor blood pressure and monitor blood oxygen and carbon dioxide

Match the names of the cranial nerves with their functions.

Oculomotor: Controls muscles that move the eye and control the amount of light entering the eye (pupil size) Accessory: Controls muscles of neck (trapezius and sternocleidomastoid) Olfactory: Sensory information for the sense of smell Hypoglossal: Controls muscles that move the tongue Glossopharyngeal: Controls muscles for swallowing and salivary glands. Sensory information from carotid arteries.

Temporal lobes

Olfaction and hearing are processed in the temporal lobes.

Name the specific region: Olfactory Bulb in image

Olfactory Bulb

Match the names of the cranial nerves with their functions/There are 12 pairs of cranial nerves. Each cranial nerve has a number and name with a specific function. Sense of vision Controls muscles of facial expression Sense of equilibrium Cutaneous sensation from the face Controls heart rate and glands in abdomen

Optic Facial Vestibulocohlear Trigeminal Vagus

Match the label to its appropriate region of the CNS: The three regions of the brain stem are the superiority positioned midbrain, the pons, and the inferiorly placed medulla oblongata. The brain stem sits superior to the spinal cord.

Pons Medulla Oblongata Spinal Cord

The corpus callosum is composed of commissural fibers, which reflects its function in allowing the right and left cerebral hemispheres to communicate

Right and Left cerebral hemispheres

medulla oblongata

Section of the brain that contains the cardiac, respiratory, vomiting and vasomotor centers and deals with autonomic functions, such as breathing, heart rate and blood pressure.

Sensory and Motor Nerves

Sensory Nerve: Afferent Fibers/ carries information to the CNS Motor Nerve: Efferent Fibers/carries information away from the CNS Mixed Nerve: Carries information both to and from the CNS

What functions to detect changes inside and outside of the body? Sensory receptors

Sensory receptors are specialized structures that monitor our internal and external environment, sending impulses to the CNS.

The branch of the peripheral nervous system that controls skeletal muscle movement is called the Somatic nervous system. The nervous system is broken up into the somatic and autonomic nervous system based on its motor functions: voluntary and involuntary control.

Somatic

The effectors of the somatic nervous system are skeletal muscles.

Somatic

Place the receptor location with the pathway that receives information from them.

Somatic Sensory Pathway: Skin, muscles, joints Visceral Sensory Pathway: Small intestines, Heart, Urinary bladder

Choroid Plexus

Specialized capillaries that secrete cerebrospinal fluid/The choroid plexuses, made of capillaries and ependymal cells, are found in the ventricles of the brain.

Insula

The deepest of the cerebral lobes, the insula, is also the smallest and least understood.

frontal lobe

The frontal lobe provides critical function in motivation, logical reasoning, expression of emotion, and social attitudes.

Motor cortex

The frontal lobes also include the primary motor cortex, which control voluntary motor functions.

Complete the sentences describing the structural and functional subdivisions of the nervous system.

The nervous system is subdivided multiple times based on the structures and the direction of nerve impulse flow.

Functions of the nervous system

The nervous system, with its sensory receptors, detects changes in the internal and external environment of the body. The nervous system sends information via a network of cells using electrical signals called impulses. By initiating responses to these changes in the body, the nervous system works to maintain homeostasis.

Occipital lobes

The occipital lobes house the visual centers, and receive inputs from the optic radiation.

Parietal lobe

The parietal lobes exhibit receipt and association of general body sensations.

Endoneurium

Tissue layer that surrounds an axon/as with skeletal muscles and their muscle fibers, a peripheral nerve consists of nerve fibers surrounded by connective tissue.

The Trigeminal nerve consists of three divisions: Opthalmic (V1), Maxillary (V2), and Mandibular (V3), which are transmitted through the superior orbital fissure, foramen rotundum, and foramen ovale. It receives sensory input from the face, oral cavity, nasal cavity, and anterior scalp; and it innervates muscles of mastication.

Trigeminal Nerve as specified in the figure

CSF (Cerebrospinal Fluid) helps control the chemical environment surrounding the brain: True

True

True: There are 31 pairs of mixed nerves that emerge from the spinal cord.

True

Match the selected cranial nerves with their function.

Vestibulocochlear nerve: conducts impulses for equilibrium and hearing Optic nerve: Vision Vagus nerve: Innervates visceral smooth muscle and cardiac muscle Glossopharyngeal: Innervates pharynx and secretion of parotid salivary gland Trigeminal nerve: Innervates muscles of mastication Hypoglossal nerve: Innervates intrinsic and extrinsic tongue muscles Facial nerve: Innervates the facial muscles

An Axon is often referred to as a nerve fiber. The axons that bring sensory information to the CNS may be called sensory fibers or afferent fibers. In contrast, motor fibers or efferent fibers conduct impulses from the CNS to effectors (muscles or glands).

What is a nerve? A nerve is a bundle of axons bound together by layers of connective tissue. How does a mixed nerve differ from a sensory nerve? From a motor nerve? Sensory nerves conduct impulses from receptors to the brain or spinal cord. Motor nerves conduct impulses from the CNS to muscle or glands. Mixed nerves contain the axons of both sensory and motor neurons.

CSF leaves the subarachnoid space via the arachnoid villi and enters the bloodstream/ to enter the dural sinuses.

arachnoid villi

somatic sensory division

carries signals from receptors in the skin, muscles, bones, and joints

Cerebral spinal fluid is formed in the

choroid plexus

internal intercostals action

depresses ribs during forced expiration

external intercostal muscles function

elevate ribs during inspiration

Which of the following elevates the ribs?

external intercostals

Lobes of the Cerebrum: The largest area of the brain, known as the cerebrum, is divided into five different anatomical areas that are each marked by differing functional roles.

frontal, parietal, temporal, occipital, insula

The pineal gland secretes a hormone involved with circadian rhythm called: Melatonin

melatonin

Pons

part of brainstem- regulates respiration reflexes, relays sensory information

midbrain

part of brainstem; controls pupil dilation and eye movement reflexes

The connective tissue wrapping that surrounds bundles (fascicles) of axons is the

perineurium

Damage to the pineal gland would likely have the most impact on the sleep wake cycle. The pineal gland secretes melatonin, which is involved in the sleep-wake cycle.

sleep/wake cycle

The most direct effect of severing the corpus callosum would be that the cerebral hemispheres could not directly communicate.

the corpus callosum allows the cerebral hemispheres to communicate.

Parietal lobes

the parietal lobes exhibit receipt and association of general body sensations.

The portion of the nervous system that conducts impulses from the skin, joints, skeletal muscles, and special senses is the ___________ division.

→ somatic sensory