Neuro Anatomy and Physiology PDF

Concepts in Anatomy & Physiology MPAS 5003 Neuro Anatomy and Physiology Nervous system Parts of the brain Cerebrum Diencephalon Brainstem Cerebellum Vasculature of the brain Cranial nerves Spinal cord structure Spinal nerves structure Dermatomes Autonomic nervou...

Concepts in Anatomy & Physiology MPAS 5003 Neuro Anatomy and Physiology Nervous system Parts of the brain Cerebrum Diencephalon Brainstem Cerebellum Vasculature of the brain Cranial nerves Spinal cord structure Spinal nerves structure Dermatomes Autonomic nervous system Parts of the brain Cerebrum Diencephalon Midbrain is top of brainstem Brainstem Cerebellum Parts of the brain Cerebrum Cerebral cortex 3mm thick, highly folded gray matter Gray matter is where the actual work is happening All of the while is myelinated for fast connection but the gray is the main work horse Parts of the brain Cerebrum Cerebral cortex 5 lobes Frontal Parietal Temporal Occipital Insula (behind temperal) Wernickes area (how we choose our works (disorganized but fluent) Insula = man of many hats Gustatory = taste Parts of the brain Lobe Functions Frontal Skeletal muscle movement Decision-making Problem-solving / planning Speech (broacas area) Behavior Parietal Somatosensory processing and interpretation (touch, temp, pain, vibratory…) Language comprehension Temporal Auditory processing and interpretation Olfactory processing and interpretation Language comprehension Memory (HUGE IMPORTANT HIPACAMPUS FILER) Emotion Occipital Visual processing and interpretation Insula Gustatory processing and interpretation Risk-reward behavior Emotion Cognition  Parts of the brain Cerebrum Cerebral cortex Limbic system (NO CLEAR BOUNDARIES) Cingulate gyrus – emotions, learning, motivation Fornix – recall memory (CONNECTED TO THE HIPPOCAMPUS) Mammillary body – episodic memory Hippocampus & entorhinal cortex – memory consolidation Amygdala – emotional responses; memory (infront of hippocampus) (hypothalamus) – not part of libic system (olfactory bulbs) – not tech part of libic COPUS COLOSUM (CONNECTS THE TWO LOBES) (not part of the limbic) Parts of the brain Cerebrum Cerebral cortex Limbic system Basal nuclei (ganglia) Helps get everything coordinated instead of walking shaky Caudate Putamen Globus pallidus Substantia nigra (hard to initiate movement, small movements, parkinsons) Nucleus accumbens Parts of the brain Cerebrum Cerebral cortex Limbic system Basal nuclei Parts of the brain Cerebrum Cerebral cortex Limbic system Basal nuclei Internal capsule Parts of the Thalamus brain Diencephalon Hypothalamus Thalamus (Thalami) Hypothalamus Epithalamus Pineal gland Pituitary gland  Parts of the brain Cerebellum Balance Positioned in space Involuntary movements Repetative movements (In stroke we tell them to touch nose then my finger) Parts of the brain Brainstem Midbrain Pons Medulla oblongata Vasculature of the brain 2 arterial circulatory routes to the brain Anterior Common carotid Internal carotid Middle cerebral a. Anterior cerebral a. Posterior Subclavian Vertebral Brachial Cerebellar arteries Posterior cerebral a. Connection = Circle of Willis Anterior (1) and posterior (2) communicating arteries Circle of Willis Vasculature and brain pathology Blockage to a vessel causes loss of Anterior cerebral function in areas that receive blood from Medial frontal and parietal lobe that artery Middle cerebral Lateral frontal, parietal, temporal, insula Hemiparesis neglect Posterior cerebral Occipital, thalamus Basilar Brainstem, cerebellum Brainstem Stoke here and you can only move eyes Cerebellum stroke they cant walk balanced Vasculature and brain pathology Circle of Willis is common site for aneurysms (85% of intracranial aneurysms) Vasculature of the brain Venous system Veins drain into sinuses which ultimately drain into internal jugular veins  Table 6.8 TABLE 6.8 The Cranial Nerves Cranial Nerves Name I. Olfactory II. Optic Fibers Afferent Afferent Comments Carries input from receptors in olfactory (smell) neuroepithelium* Carries input from receptors in eye* III. Oculomotor Efferent Innervates skeletal muscles that move eyeball up, down, and medially, and raise upper eyelid; innervates smooth muscles that constrict pupil and alter Know the name, lens shape for near and far vision Afferent Transmits information from receptors in muscles IV. Trochlear Efferent Innervates skeletal muscles that move eyeball downward and laterally number, fiber, Afferent Transmits information from receptors in muscles origin, and V. Trigeminal Efferent Afferent Innervates skeletal muscles used for chewing Transmits information from receptors in skin; skeletal muscles of face, functions of the 12 VI. Abducens Efferent nose, and mouth; and teeth sockets Innervates skeletal muscles that move eyeball laterally cranial nerves VII. Facial Afferent Efferent Transmits hearing and balance information from receptors in muscles Innervates skeletal muscles of facial expression and swallowing; innervates Afferent = sensory Afferent nose, palate, and lacrimal and salivary glands Transmits information from taste buds in front of tongue and mouth Efferent = motor VIII. Vestibulocochlear Afferent Transmits hearing and balance information from receptors in inner ear Innervates skeletal muscles involved in swallowing and parotid salivary IX. Glossopharyngeal Efferent gland Afferent Transmits information from taste buds at back of tongue and receptors in auditory-tube skin; also transmits information from carotid artery baroreceptors (blood pressure receptors) and from chemoreceptors that detect changes in blood gas levels X. Vagus Efferent Innervates skeletal muscles of pharynx and larynx and smooth muscle and glands of thorax and abdomen Afferent Transmits information from receptors in thorax and abdomen XI. Accessory Efferent Innervates sternocleidomastoid and trapezius muscles in the neck XII. Hypoglossal Efferent Innervates skeletal muscles of tongue *The olfactory and optic pathways are CNS structures so are not technically “nerves.”  Cranial Nerves CN diagram CN mnemonics CN gestures LOOK UP CRANIAL NUMBER GUY  Spinal Cord Structure Gray matter White matter Spinal nerve Together for a Very short time Unless you kill cell body then the axon or dendrites can Grow back Anterior > Anterior roots - leaving Posterior root – sensory coming in Spinal Cord White matter tracts Ascending (sensory) & Descending (motor) Named for where they originate and end (Ex – cortico-spinal vs spinothalamic) Cortico - cortex  White matter tracts Ascending Anterior and lateral Tracts to know Spinothalamic Dorsal columns Eventually both cross over but Dorsal crosses at meduala not like The spinothalmic in the lumbar Spinothalamic Dorsal column  White matter tracts Descending Posterior and medial Tracts to know Corticospinal (lateral and ventral) Rubrospinal Corticospinal Rubrospinal Spinal Nerves < Structure Spinal nerve Dorsal root Dorsal root ganglion Ventral root Dermatomes and myotomes Peripheral Nerves Somatic nervous system 1 neuron NT = acetylcholine Receptor = nicotinic Autonomic nervous system Sympathetic and parasympathetic 2 neurons with ganglion 1st NT = acetylcholine; receptor = nicotinic 2nd NT different Sympathetic Fight or flight responses Exits spinal cord at thoracic and lumbar levels Ganglia = parallel tract along spinal column 2nd NT = norepinephrine or epinephrine Receptors = alpha or beta EITHER HAVE P SYMP. OR SYMP. IN ONE SPINAL BONE Parasympathetic Rest and digest responses Exits spinal cord at cervical and sacral levels Ganglia = within organs 2nd NT = acetylcholine Receptors = muscarinic  STUDY CARIO STUFF Table 6.11 TABLE 6.1 1 Some Eff ects of Autonomic Ne rvous System Activity Sympathetic Nervous System Effect and Receptor Parasympathetic Nervous System Effect (All M-ACh Effector Organ Types* Receptors) Eyes Iris muscle Contracts radial muscle (widens pupil), α1 Contracts sphincter muscle (makes pupil smaller) Ciliary muscle Relaxes (flattens lens for far vision), β2 Contracts (allows lens to become more convex for near vision) Heart SA node Increases heart rate, β1 Decreases heart rate Atria Increases contractility, β1 , β2 Decreases contractility AV node Increases conduction velocity, β1 , β2 Decreases conduction velocity Ventricles Increases contractility, β1 , β2 Decreases contractility slightly Arterioles Coronary Constricts, α1 , α2 —† Dilates, β2 Skin Constricts, α1 , α2 — Skeletal muscle Constricts, α1 — Dilates, β2 Abdominal viscera Constricts, α1 — Kidneys Constricts, α1 — Salivary glands Constricts, α1 , α2 Dilates Veins Constricts, α1 , α2 — Dilates, β2 Lungs Bronchial muscle Relaxes, β2 Contracts Salivary glands Stimulates secretion, α1 Stimulates watery secretion Stimulates enzyme secretion, β1 Stomach Motility, tone Decreases, α1 , α2 , β2 Increases Sphincters Contracts, α1 Relaxes Secretion Inhibits (?) Stimulates Intestine Motility Decreases, α1 , α2 , β1 , β2 Increases Sphincters Contracts (usually), α1 Relaxes (usually) Secretion Inhibits, α2 Stimulates Gallbladder Relaxes, β2 Contracts Liver Glycogenolysis and gluconeogenesis, α1 , β2 — Pancreas Inhibits secretion, α Stimulates secretion Exocrine glands Inhibits secretion, α2 — Endocrine glands Stimulates secretion, β2 Adipose cells Increases fat breakdown, α2 , β3 — Kidneys Increases renin secretion, β1 — Urinary bladder Bladder wall Relaxes, β2 Contracts Sphincter Contracts, α1 Relaxes Uterus Contracts in pregnancy, α1 Variable Relaxes, β2 Reproductive tract (male) Ejaculation, α1 Erection Skin — Muscles causing hair Contracts, α1 erection — Sweat glands Secretion from hands, feet, and armpits, α 1 — Generalized abundant, dilute secretion, M-AChR Lacrimal glands Minor secretion, α1 Major secretion Nasopharyngeal glands — Secretion *Note that m any ef fector organs cont ain bot h al pha-adrenergic and beta-adrenergic receptors. Activat ion of t hese recept ors may produce eit her t he same or opposing ef fect s. F or simpli cit y, except for the arterioles and a f ew ot her cases, only t he dom inan t sympat hetic eff ect is given when t he t wo receptors oppose each ot her. †A dash m eans these cell s are not innervated by thi s branch of the autonom ic nervous system or that t hese nerves do not have a signif icant physiological functi on.