Ch. 8 Lecture BSC228 Student Handout PDF

Because learning changes everything.® Chapter 8 The Central Nervous System Lecture Outline Human Physiology Sixteenth Edition Stuart Ira Fox Krista Rompolski Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw H...

Because learning changes everything.® Chapter 8 The Central Nervous System Lecture Outline Human Physiology Sixteenth Edition Stuart Ira Fox Krista Rompolski Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. I. Structural Organization of the Brain Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 2  A. Central Nervous System 1 1. The CNS is composed of the ___________ brain'sSpinal cord 2. a. Receives input from sensory ______neurons and directs activity of motor neurons that innervate muscles and glands b. Loading… Association neurons integrate sensory information and help direct the appropriate response to maintain homeostasis and response to the environment. c. Responsible for learning and memory Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 3 Central Nervous System 2 3meningesa (Arachnoid Arachnoid mater mater inner : Dia D ↓ ↓ Cerebellum ↓ cord exam Spinal ↓ brain stem L pituitary ↓ cerebrum Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 4 Ventricle of the Brain & Loading… m Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 8  "Wrinkly part" of brain II. The Cerebrum Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 9 Lobes of the Cerebrum primaryrouse sensory Oneurons Succeala Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 12  Functional Regions of the Cerebrum movement O ofa understandi & written ↳ Speech - S hot , cold pain, etc , relate to memories Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 13 Maps of the Precentral and Postcentral Gyri Left right motormore motor ger sensory neuronsbig Detect texture, pressure 3 temp , deep deep superficial superficial O * 5 lobe Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 15  eX) lobe is "occipital Functions of the Cerebral Lobes responsiblefor TABLE 8.1 Functions of the Cerebral Lobes Lobe Functions Exam Frontal Voluntary motor control of skeletal muscles; personality; higher intellectual processes (for example, concentration, planning, and decision making); verbal communication Parietal Somatesthetic interpretation (for example, cutaneous and muscular sensations); understanding speech and formulating words to express thoughts and emotions; interpretation of textures and shapes Temporal Interpretation of auditory sensations; storage (memory) of auditory and visual experiences Occipital Integration of movements in focusing the eye; correlation of visual images with previous visual experiences and other sensory stimuli; conscious perception of vision Insula Memory; sensory (principally pain) and visceral integration Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 17  D. Cerebral Lateralization (Dominance) 1 1. Each side of the precentral gyrus controls movements on the _________ contralateral (opposite) side of the body due to decussation of fibers. 2. Somatesthetic sensation from each side of the body projects to __________ contralateral sides of the postcentral gyrus. 3. Loading… Communication between the sides occurs through the corpus callosum; this is severed in severe forms of = epilepsy. I R - - - Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 19  Cerebral Lateralization (Dominance) 2 1. Some tasks seem to be performed better by one side of the brain than the other. a. __________: right hemisphere visuospatial tasks, recognizing faces, entionshipcomposing creative s music, arranging blocks, reading maps, comprehension of patterns, part-whole relationships b. __________: left hemisphere Language, analytical ability, speech, writing, calculations, understand O mainnie visual appearance music, describe > - Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 20 Cerebral Lateralization LR of O O typicalonnected Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 21  F. The Limbic System and Emotion 1 1. Group of brain regions responsible for emotional drives a. Areas of the cerebrum included: cingulate gyrus, amygdaloid body, hippocampus, septal = nuclei, anterior insula - * I memory stored b. The hypothalamus and thalamus (in the diencephalon) are also part of this system Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 28  -green The Limbic System 3 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 30  The Limbic System 4 emotionaleories from smell 1. Once called the rhinencephalon, or “smell brain,” because it deals with olfaction but it’s main function is the center of emotional drives. 2. There are few synaptic connections between the limbic system and the cerebral cortex, which is why it is hard to control your emotions. frontal S much lobefrontal lobe development I controled better Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 31  The Limbic System 5 1. Emotions controlled by the limbic system: a. ________: aggression areas in the amygdaloid body and hypothalamus b. fear _______: amygdaloid body and hypothalamus c. feeding Hunger/satiety: hypothalamus ________: d. ________: sex drive the whole system, including the cerebrum e. Goal-directed behaviors: hypothalamus and frontal I cortex planned hypothalamus - 3 thought · on out each emot in Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 32  G. Memory 1 1. Brain Areas a. Studies of people with amnesia reveal that areas of the temporal lobe, hippocampus, the head of the caudate nucleus, and dorsomedial thalamus are involved in memory. b. The _________ amygdaloid body is involved with conversion of short- term memory into long-term memory, fears aggression - c. The prefrontal ________ cortex may be involved in complex problem solving and working memory–very Oshort-term memory. -not good in ADHD Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 33 A. Emotions and Memory 1 1. Limbic System a. Emotions sometimes strengthen and other times weaken memory formation. b. If the memory has an emotional component, the amygdaloid body is involved in memory formation. c. Stress ________ impairs memory consolidation in the hippocampus and working memory function of the prefrontal cortex. -not "downloaded"Wo stress d. Posttraumatic stress disorder may result in hippocampal atrophy. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 50 Emotions and Memory 2 Limbic System, continued e. The amygdaloid body and hippocampus have receptors for stress hormones, ___________. such as cortiso f. It is thought that cortisol may strengthen emotional memory formation via the amygdaloid body but weaken hippocampal memory formation and memory retrieval. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 51 Brain Regions Involved in Emotion CGinspiration/iStock/Getty Images for B. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 52  C. Hypothalamus and Pituitary Gland 1 1. Hypothalamus -creates hormones a. Very important for maintaining homeostasis and regulating the autonomic system. Contains centers for: 1) Hunger/satiety and thirst 2) Regulation of body temperature 3) Regulation of sleep and wakefulness 4) Sexual arousal and performance 5) Emotions of fear, anger, pain, and pleasure 6) Visceral responses to emotion 7) Controls hormone secretion from the pituitary gland Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 59  B. Hindbrain 3 c. Cerebellum 1) Second largest brain structure; gray matter outside, white matter inside 2) Receives input from proprioceptors in joints, tendons, and muscles 3) Works with the basal nuclei and motor cortex to coordinate movement a) Fibers from the cerebellum pass through the red nucleus to the thalamus and then to the motor cortex Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 72  B. Hindbrain 4 Cerebellum, Continued 1) The cerebellum is needed for motor learning and the proper timing and force required to move limbs in a specific task. 2) Required for maintaining posture and balance. 3) The cerebellum influences motor coordination through inhibition on the motor cortex from Purkinje cells. 4) May have roles in acquisition of sensory data, memory, emotion, and other higher functions Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 73  C. Reticular Activating System 1 1. To fall asleep, we must tune out sensory stimuli. When awake, we are alert to sensory stimuli. 2. This depends on the activation and inhibition of the reticular activating system (RAS). a. Includes the pons and reticular formation of the midbrain Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 77 Structures of the RAS Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 78  Reticular Activating System 2 1. Arousal from sleep and alertness: a. Neurons from the pons release ACh on the thalamus. This enhances passing of sensory information to the cerebral cortex. b. Neurons from the hypothalamus and basal forebrain release monoamines onto the cerebrum, further enhancing alertness. c. Neurons from the lateral hypothalamic area release arousing polypeptide hormone, orexin (hypocretin) 1) Loss of these neurons leads to narcolepsy. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 79  Reticular Activating System 3 1. Sleep a. Neurons from the ventrolateral preoptic nucleus (VLPO) of the hypothalamus release GABA into other areas of the RAS. b. This inhibits the RAS and allows sleep. c. This activity is increased with depth of sleep. 2. Many drugs act on the RAS to promote either sleep (Benadryl® and Ambien®) or wakefulness (caffeine). Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 80  Loading… Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior https://www.pharmacy180.com/article/spinal-cord-3554/ written consent of McGraw Hill LLC. 81  V. Spinal Cord Tracts Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 82  A. Introduction: Spinal Cord Tracts 1 1. The spinal cord is composed of _____ White matter surrounding a ______ grey matter core a. Extends from the foramen magnum of the skull to the first lumbar vertebra. b. The gray matter is arranged in the shape of an H with left and right dorsal (posterior) horns and left and right ventral (anterior) horns. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 83  Introduction: Spinal Cord Tracts 2 1. The white matter is composed of ascending and descending fiber tracts. a. Arranged into six columns called ___________ column called funiculi b. Ascending tracts carry _______ sensoryimpulses impulses and are given the prefix spino- with a suffix that indicates the brain region it synapses on; ex – lateral spinothalamic tract to brain c. Descending tracts carry motor _______ impulses impulses and are given the suffix -spinal, and the prefix indicates the brain region they come from; ex – anterior corticospinal tract brain down Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 84 wine - - wider · I tell lateral u9 https://doctorlib.info/anatomy/neuroanatomy- ventral illustrated-colour-text/neuroanatomy-illustrated-colour- Copyright 2022 © McGraw Hill LLC. All rights reserved. Notext.files/image118.jpg reproduction or distribution without the prior written consent of McGraw Hill LLC. 85  B. Ascending Tracts 1 1. Convey sensory information from cutaneous receptors (skin), proprioceptors (muscles and joints), and visceral receptors (internal organs) 2. ___________ (decusation)may occur in the spinal cord or in the crossover of tracts medulla. This means that the origin of the input and the brain area are contralateral. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 86 Ascending Tracts 2 TABLE 8.4 Principal Ascending Tracts of the Spinal Cord Tract Origin Termination Function Anterolateral Posterior horn on one Thalamus, then cerebral Conducts pain and temperature spinothalamic side of cord but crosses cortex impulses that are interpreted to opposite side within cerebral cortex Dorsal column- Peripheral afferent Nucleus gracilis and Conducts sensory impulses medial lemniscus neurons; ascends on nucleus cuneatus of from skin, muscles, tendons, ipsilateral side of spinal medulla; eventually and joints, which are cord but crosses over thalamus, then cerebral interpreted as sensations of in medulla cortex cutaneous touch and pressure, and body position Posterior Posterior horn; does not Cerebellum Conducts sensory impulses spinocerebellar cross over from one side of body to same side of cerebellum; necessary for coordinated muscular contractions Anterior Posterior horn; some Cerebellum Conducts sensory impulses spinocerebellar fibers cross, others do from both sides of body to not cerebellum; necessary for coordinated muscular contractions Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 88 Ascending Tracts 3 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 89  C. Descending Tracts 1 1. Two major groups: a. _____________: cortico descend directly without synaptic spinal/pyramidal interruption from the cerebral cortex to the spinal cord 1) Cell bodies of these neurons are located in the precentral gyrus (Primary motor cortex) and superior frontal gyrus (Supplementary motor complex). 2) 80 to 90% cross in the medulla pyramids and descend as lateral corticospinal tracts. Involved with movement of the contralateral limbs. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 90  C. Descending Tracts 2 Corticospinal or pyramidal tracts, continued 1) Those that do not cross in the medulla, descend as anterior corticospinal tracts and cross in the _________ Spinal cord at the level that the nerves leave the cord. These tracts primarily control the muscles of the axial skeleton. 2) The corticospinal tracts are mainly concerned with the control of fine movements that require dexterity. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 91 Descending Pyramidal Tracts Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 92  Descending Tracts 2 b. ____________: extrapyramidal originate in the brain stem and are tracts controlled by the motor circuits of the corpus striatum, substantia nigra, and thalamus 1) Symptoms of Parkinson disease reveal the importance of these tracts for initiating body movements, maintaining posture, and controlling facial expression. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 93  Descending Tracts 3 Extrapyramidal Tracts, Continued 1) ___________ reticulospinal tracts are the major descending extrapyramidal tracts (crossed). a) These originate in the reticular formation of the brain stem. This area is stimulated or inhibited by neurons from the cerebellum, basal nuclei, and cerebrum. 2) __________ Vestibulospinal tracts arise from the vestibular nuclei in the medulla oblongata (uncrossed) 3) __________ rubrospinal arise from the red nucleus (crossed) tracts Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 94 Higher Motor Neuron Control of Skeletal Muscles Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 95  VI. Cranial and Spinal Nerves Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 98  A. Cranial Nerves 1 1. Part of the PNS 2. Nerves that arise directly from nuclei in the brain 3. Twelve pairs 4. Most are mixed nerves with both sensory and motor neurons (somatic and parasympathetic) 5. Those associated with vision, olfaction, and hearing are sensory only and have their cell bodies in ganglia located near the sensory organ. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 99 A. Cranial Nerves 2 Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 100  Cranial Nerves 3 TABLE 8.6 Summary of Cranial Nerves Number and Name Composition Function I Olfactory Sensory Olfaction II Optic Sensory Vision III Oculomotor Somatic motor Motor impulses to levator palpebrae superioris and extrinsic eye muscles, except superior oblique and lateral rectus; innervation to muscles that regulate amount of light entering eye and that focus the lens IV Trochlear Somatic motor Motor impulses to superior oblique muscle of eyeball V Trigeminal Ophthalmic division Sensory Sensory impulses from cornea, skin of nose, forehead, and scalp Maxillary division Sensory Sensory impulses from nasal mucosa, upper teeth and gums, palate, upper lip, and skin of cheek Mandibular division Sensory Sensory impulses from temporal region, tongue, lower teeth and gums, and skin of chin and mandible Sensory: Proprioception from muscles of mastication proprioception Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 101  Cranial Nerves 4 TABLE 8.6 Summary of Cranial Nerves (Continued) Number and Name Composition Function VI Abducens Somatic motor Motor impulses to lateral rectus muscle of eyeball VII Facial Somatic motor Motor impulses to muscles of facial expression and muscle that tenses the stapes Parasympathetic motor Secretion of tears from lacrimal gland and salivation from sublingual and submandibular salivary glands Sensory Sensory impulses from taste buds on anterior two- thirds of tongue; nasal and palatal sensation VIII Vestibulocochlear Sensory Sensory impulses associated with equilibrium Sensory impulses associated with hearing IX Glossopharyngeal Somatic motor Motor impulses to muscles of pharynx used in swallowing Sensory Sensory impulses from pharynx, middle-ear cavity, carotid sinus, and taste buds on posterior one-third of tongue Parasympathetic motor Salivation from parotid salivary gland Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 102  Cranial Nerves 5 TABLE 8.6 Summary of Cranial Nerves (Continued) Number and Name Composition Function X Vagus Somatic motor Contraction of muscles of pharynx (swallowing) and larynx (phonation) Sensory Sensory impulses from taste buds on rear of tongue; sensations from auricle of ear; general visceral sensations Parasympathetic motor Regulation of many visceral functions XI Accessory Somatic motor Laryngeal movement; soft palate Motor impulses to trapezius and sternocleidomastoid muscles for movement of head, neck, and shoulders XII Hypoglossal Somatic motor Motor impulses to intrinsic and extrinsic muscles of tongue and infrahyoid muscles Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 103  B. Spinal Nerves 1. Part of the PNS 2. Nerves that arise directly from the spinal cord 3. __ 3) g cervical, ___ pairs: ___ 12 thoracic, __ b lumbar, __ 5 sacral, 1 coccygeal 4. All are mixed nerves that separate near the spinal cord into a dorsal root carrying sensory fibers and a ventral root carrying motor fibers. a. The ________ dorsal houses the sensory neuron cell root bodies. b. Motor neuron cell bodies are in the ___________ ventral gray horns Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 104 Distribution of Spinal Nerves Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 105  C. Reflex Arc 1 1. Unconscious motor response to a sensory stimulus 2. Parts of an arc a. Sensory receptor b. Sensory neuron c. Interneuron in CNS (spinal cord gray matter; missing in 2-neuron arcs) d. Somatic motor neuron e. Effector – muscle or gland that responds Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 106  Reflex Arc 2 1. Types of arcs a. __________ somatic reflex – effectors are skeletal muscles b. ___________ autonomic reflex – effectors are smooth muscle, cardiac muscle, or glands Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 107 Somatic Reflex Arc Access the text alternative for slide images. Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC. 108  End of Main Content Because learning changes everything.® www.mheducation.com Copyright 2022 © McGraw Hill LLC. All rights reserved. No reproduction or distribution without the prior written consent of McGraw Hill LLC.