Exam #2 on Thursday Bring scantron. Same format. exam #2 covers chapters exam #2 does NOT cover ANS

1.Where is the dura mater in relationship to the skull? 2.If someone had a blockage in the cerebral aqueduct, could CSF flow from the 3 rd to the 4 th ventricle? 3. If someone had a stroke that affected area A, what type of symptoms would they have (be specific)? Central sulcus A 4. Name gyrus B. 5. What type of information is processed here? B

Autonomic Nervous System basic anatomy of ANS ANS vs PNS divisions of ANS sympathetic division anatomy & function ANS plexuses sympathetic response adrenal gland parasympathetic division anatomy & function visceral reflexes stress & the ANS referred pain anatomy

PNS CNS Sensory Somatic & visceral Motor ANSSomatic Sympathetic Parasympathetic

Autonomic Nervous System Visceral sensory & motor system Innervates viscera, smooth muscle, glands Autonomic = self governed Adjusts visceral functions to the body’s needs Responsible for visceral reflexes High BP Decrease Heart rate CN IX CN X

Somatic efferent innervation Autonomic efferent innervation ACh ACh or NE Autonomic ganglion ACh = Acetylcholine NE = Norepinephrine

Preganglionic neuron cell body in brain or spinal cord (lateral horn) axon is myelinated Synapses in ganglion Postganglionic neuron cell body in autonomic ganglion axon is unmyelinated synapses on visceral effector Basic anatomy of ANS

Sympathetic –Speeds up –Fight or flight Parasympathetic – slows down – rest & digest

Sympathetic division (thoracolumbar) –preganglionic neuron cell body in T1-L2 of spinal cord Parasympathetic division (craniosacral) –preganglionic neuron cell body in S2-S4 of spinal cord & brainstem –III, VII, IX & X

Sympathetic ganglia –near spine –connected via chain (sympathetic chain) –Short preganglionic neuron –Long postganglionic neuron Parasympathetic ganglia –in organ wall –not connected –Long preganglionic neuron –Short postganglionic neuron Location of ganglion

Sympathetic ganglion Communicating rami Dorsal ramus Ventral ramus Anterior (ventral) Posterior (dorsal)

Fig a(TE Art) Communicating rami Sympathetic chain

Sympathetic chain Sympathetic ganglia Sympathetic chain in thorax

Plexuses of ANS = sympathetic + parasympathetic Cardiac plexus Pulmonary plexus Celiac (solar) plexus Superior mesenteric Inferior mesenteric Hypogastric

Remember a stressful event What was that event List 5 changes that occurred in your body that you noticed during the event How long did it take for the stress response to go away?

Sympathetic responses Red = preganglionic Black = postganglionic

Adrenal cortex Adrenal medulla Cortex = steroid hormones (endocrine system) Medulla = modified sympathetic ganglion secretes epinephrine (adrenaline) & norepinephrine innervated by preganglionic sympathetic neurons products get secreted into bloodstream Adrenal gland

Sympathetic pathways all this innervation is BILATERAL (right & left) sympathetic pathways carry noxious sensory information (except in pelvis)

Parasympathetic pathways Cranial nerves: III, VII, IX & X Sacral nerves S2-S4 NT = acetylcholine Also bilateral innervation Carries most sensory info except noxious stimuli (carries pain info from pelvis)

Low BP Increase HR And constrict BV sympathetic High BP CN IX Decrease HR And dilate BV CN X Vagus Visceral reflex Beta adrenergic blockers Block sympathetic response

Gut stretch peristalsis Visceral reflex in the gut

vagus Asthma parasympathetic response bronchospasm increased gland activity treat with B 2 adrenergic agonists (stimulate sympathetic response)

Visceral Pain Organ & skin pain fibers travel to the spinal cord together Organ pain misinterpreted as skin pain (referred pain) –Heart & skin in left arm = spinal nerves T1-T5 –Heart attack (pain) is felt in skin (pain) along left arm & chest

T1-T4 receive visceral afferents from heart T1 dermatome Sensory from skin = green Sensory from heart = red

What is STRESS? Short term “amp” to long term amp Year after year…… Problems! - hypertension - ulcers - constipation - bladder infections - Raynaud’s - sexual dysfunction