Activity 7: Nervous System Histology, Brain, & Cranial Nerves Chapters 14 & 15 – McKinley et al., Human Anatomy, 4e. Objectives: Histology: Identify structures indicated on three different slides or images of nervous system tissue. Some of these are also visible on the classroom model of a neuron. Human brain: Identify listed structures of the human brain on classroom models, the cranial meninges, and structures involved in cerebrospinal fluid circulation. Human brain: Identify the 12 pairs of cranial nerves by name and number on a model and on the sheep brain. Dissect a sheep brain and identify structures listed. Compilation: Mohammad Tomaraei & Cristin Fail

Nervous System Tissues: Spinal Cord Smear (Histology)

Nervous System Tissues: Cross Section of a Nerve (Illustration)

Nervous System Tissues: Cross Section of a Nerve (Histology)

Nervous System Tissues: Cross Section of a Nerve (Histology)

Nervous System Tissues: Teased Myelinated Nerve Fibers (Histology)

Nervous System Tissues: Multipolar Neuron Model

Nervous System Tissues: Multipolar Neuron Illustration

Brain Anatomy – Adult Human Brain

Brain Anatomy – Sheep Brain

Brain Anatomy – Adult Human Brain

Brain Anatomy – Sheep Brain

Brain Anatomy – Sheep Brain

Brain Anatomy – Cerebrum

Brain Anatomy – Cerebrum Cerebral hemispheres are divided by the longitudinal fissure into left and right sides Central sulcus divides the frontal lobe from parietal lobes

Brain Anatomy – Lobes of the Brain

Brain Anatomy – White Matter of Cerebrum

Brain Anatomy – Cerebral Hemispheres

Brain Anatomy – Hemispheric Lateralization

Brain Anatomy – Lobes of the Brain

Brain Anatomy – Lobes of the Brain & their Functions Frontal Lobe Parietal Lobe Occipital Lobe Temporal Lobe Brain Stem Cerebellum Primary Motor Cortex (Precentral Gyrus) Voluntary motor functions Concentration Verbal communication Decision making Planning Personality Primary Somatosensory Cortex (Postcentral Gyrus) Sensory functions (Pain, heat and other sensations) Comprehension of language Primary Visual Cortex Processing visual information Storing visual memories Understanding Speech Interpretation and storage of auditory and olfactory sensations Breathing Swallowing Heart rate Includes Midbrain, Pons, and Medulla Oblongata Coordination Balance Stores memories of previously learned movement patterns

Brain Anatomy – Primary Somatosensory Cortex The amount of cortex devoted to any given body region is proportional to how richly innervated that region is.

Brain Anatomy – Homunculus Model Which model is more realistic?

Brain Anatomy – Cross-section Brain Model Corpus Callosum Corpora Quadrigemina (Tectal Plate) Superior Colliculus (pl. colliculi) Inferior Colliculus Cerebellum (Arbor Vitae) 4th Ventricle Central canal of spinal cord Medulla Oblongata Pons Pituitary gland Optic Chiasm Hypothalamus Thalamus Septum Pellucidum Fornix Pineal Gland

Brain Anatomy – Corpus Callosum Carries messages between the left and right hemispheres Its under surface forms the roof of the body of the lateral ventricle.

Brain Anatomy - Diencephalon Sits on top of the brain stem Enclosed by the cerebral hemispheres Made of three parts Thalamus Hypothalamus Epithalamus

Brain Anatomy - Diencephalon

Brain Anatomy – Epithalamus & Pineal Gland Pineal gland is an endocrine gland that secretes the hormone Melatonin. Melatonin helps regulate day-night cycles known as the body’s Circadian Rhythm.

Brain Anatomy – Thalamus & the Interthalamic Adhesion The Interthalamic Adhesion is located midsagitally and connects the left and right thalamic bodies

Brain Anatomy – Hypothalamus Includes: Pituitary Gland Mammillary Body Optic Chiasm Optic Tracts Infundibulum 3rd Ventricle

Brain Anatomy – Functions of Hypothalamus Master control of the autonomic nervous system Heart rate, blood pressure, digestive activities and respiration Master control of the endocrine system Metabolism, growth, stress responses and reproduction Regulation of body temperature Body’s “thermostat”, detects altered blood temperatures, heat or cool the body: shivering/sweating Control of emotional behavior Emotional responses: pleasure, aggression, fear, rage, contentment and sex drive Control of food intake Monitors levels of glucose and amino acids in the blood and produces sensations of hunger Control of water intake Monitors blood solute concentration Regulation of sleep-wake rhythms The Suprachiasmatic Nucleus directs the Pineal gland to secrete melatonin, regulating circadian rhythms.

Brain Anatomy – Brain Stem Includes: Midbrain (mesencephalon) Pons Medulla Oblongata

Brain Anatomy – Overview of Brain Stem Functions

Brain Anatomy – Midbrain Includes: Corpora Quadrigemina (tectal plate) Superior Colliculus: Visual reflex center (turns eyes and head in response to visual stimulus) Inferior Colliculus: Auditory reflex center (turns eyes and head in the direction of a sound) Cerebral Peduncles

Brain Anatomy – Pons Functions: Bridge between the cerebellum and cerebrum Houses cranial nerves Trigeminal (CN V) Abducens (CN VI) Facial (CN VII) Some of the nuclei for Vestibulocochlear (CN VIII) Helps regulate skeletal muscles of breathing

Brain Anatomy – Medulla Oblongata Functions: Regulates heart rate and strength of contraction Controls blood pressure Regulates respiratory rate Involved in coughing, sneezing, salivating, swallowing, gagging and vomiting

Brain Anatomy – Medulla Oblongata & Pons

Brain Anatomy – Medulla Oblongata & Pons

Brain Anatomy – Cerebellum Functions: Processes sensory input Coordinates movement output Balance Includes: Vermis Separates right and left hemispheres Arbor Vitae (“tree of life”)

Brain Anatomy – Cerebellum

Brain Anatomy – Cerebellum

Brain Anatomy – Meninges and Spaces

Brain Anatomy – Cranial Dural Septa

Brain Anatomy – Dural Venous Sinuses

Brain Anatomy – Ventricles

Brain Anatomy – Ventricles

Brain Anatomy – Circulation of Cerebrospinal Fluid

Brain Anatomy – Cranial Nerves Olfactory nerve (I) Optic nerve (II) Oculomotor nerve (III) Trochlear nerve (IV) Trigeminal nerve (V) Abducens nerve (VI) Facial nerve (VII) Vestibulocochlear nerve (VIII) Glossopharyngeal nerve (IX) Vagus Nerve (X) Accessory Nerve (XI) Hypoglossal nerve (XII)

Brain Anatomy – Cranial Nerves

Brain Anatomy – Cranial Nerves Sensory, Motor or Both Some Say Marry Money But My Brother Says Big Brains Matter Most

Brain Anatomy – Origins of Cranial Nerves

Brain Anatomy – Sheep Brain

Brain Anatomy – Sheep Brain

Brain Anatomy – Trigeminal Nerve

Brain Anatomy – Facial Nerve

Brain Anatomy – Vestibulocochlear Nerve

Brain Anatomy – Glossopharyngeal Nerve

Brain Anatomy – Vagus Nerve

Brain Anatomy – Accessory & Hypoglossal Nerve

Brain Anatomy – Cerebral Nuclei Includes: Caudate Nucleus Lentiform Nucleus Putamen Globus Pallidus Claustrum Amygdaloid body

Brain Anatomy – Cerebral Nuclei

Brain Anatomy – Functions of Cerebral Nuclei Caudate Spatial processing Posture and directed movements Putamen Controls muscular movements at the subconscious level Globus Pallidus Excites and inhibits the activities of the thalamus to control muscle tone Amygdaloid body Expression of emotions , control of behavioral activities, development of moods Claustrum Processes visual information at a subconscious level

Brain Anatomy – Lobes & Structures of the Brain G. B. F. C. E. D. http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif

Brain Anatomy – Lobes & Structures of the Brain A. Central Sulcus B. Frontal Lobe C. Lateral Fissure A. (groove) G. D. Temporal Lobe B. F. E. Transverse Fissure F. Occipital Lobe C. (groove) G. Parietal Lobe E. D. (groove) http://williamcalvin.com/BrainForAllSeasons/img/bonoboLH-humanLH-viaTWD.gif