1. General Organization CNS (Brain + Spinal Cord) Peripheral NS (= PNS) Afferent Efferent Somatic Autonomic Sympathetic Parasympathetic

2. Protection of CNS Mechanical Bony covering (skull, vertebrae) Meninges (dura mater, arachnoid mater, pia mater) Chemical Blood-Brain Barrier (hypothalamus is “outside”)

3. Cerebral Cortex Organization Layers I-VI Vertical columns

4. Gross Anatomy of Cerebral Cortex Four pairs of lobes (bilaterally symmetric)

5. Parietal Lobes Sensory input from body surface (touch, pressure, heat, cold, pain, proprioception) Sensory homunculus

6. Frontal Lobes Voluntary movement, speech Motor homunculus Sensory Motor Brain plasticity

7. Specific Cortical Areas Broca’s area (formation of words) Wernicke’s area (speech recognition) Association areas Prefrontal association cortex Parietal-temporal-occipital association cortex Limbic association cortex (in temporal lobe)

8. Subcortical Structures Basal nuclei (= basal ganglia). Lesions cause resting tremors Thalamus Hypothalamus Limbic system (includes parts of cerebral cortex, basal nuclei, thalamus and hypothalamus)

9. MEMORY Short term (seconds to 6 hours) Long term (days to decades) Consolidation Amnesia Retrograde Anterograde

10. CEREBELLUM Motor coordination: Fine movements (writing, playing musical instrument) Coarse movement (posture, walking) Lesions cause intention tremor, poor balance, poor muscle tone, poor coordination

11. Brain Stem Connects cerebrum and cerebellum to spinal cord Includes areas that control “vital activities” (respiration, heart rate, arterial pressure, gastrointestinal activities) Cranial nerves (12 pair; vagus) Reticular formation and reticular activating system Controls alertness and level of attention (arousal) States of arousal: Maximal alertness Wakefulness Sleep Coma

12. Spinal Cord Gray matter inside, white matter outside Ascending and descending tracts Spinal reflex arc

13. Peripheral NS: Afferent Receptors as transducers Sensations vs perceptions How receptors work Stimulation usually increases Na permeability This lessens negativity of receptor cell When receptor is a neuron, this is a receptor potential When receptor isn’t a neuron, this is a generator potential Receptor and generator potentials are graded potentials at low levels of stimulus strength

14. Coding of Stimulus Strength Frequency coding (afferent neuron generates action potentials at higher frequencies as stimulus strength increases) Population coding (more afferent neurons generate action potentials as stimulus strength increases) Adaptation Phasic receptors (respond to rate of change in stimulus strength) Tonic receptors (pain; proprioception)

15. Somatic vs Special Senses Special senses = taste, olfaction, vision, hearing Somatic senses are those originating on body surface (pressure, touch, heat, cold) and proprioception Labeled lines, referred pain and phantom pain Receptive fields and sensory acuity

16. Pain and Analgesia Nociceptors (pain receptors): A-Delta fibers (fast; sensitive to heat and mechanical stimuli) C-Fibers (slow; sensitive to chemical stimuli) Analgesia and endorphins Central pain Chronic inflammation following injury to peripheral nerve Uninterrupted except by sleep http://www.practicalpainmanagement.com/critical- necessity-diagnose-pain-centralizedhttp://www.practicalpainmanagement.com/critical- necessity-diagnose-pain-centralized

17. Peripheral NS – Efferent General Autonomics Architecture of systems (preganglionic and postganglionic cells) Sympathetic trunk (= sympathetic ganglion chain) Collateral ganglia in sympathetic system Parasympathetic ganglia Transmitters in autonomics Preganglionic fibers are cholinergic Postganglionic fibers are cholinergic in parasympathetics, adrenergic in sympathetics

18. Resting outputs and autonomic tone Autonomic dominance Sympathetic (flight or fight) Parasympathetic (vegetative)

19. Somatic Nervous System Voluntary, not necessarily conscious One neuron from CNS to effector cell (unlike autonomic) Stimulation only, no inhibition. Motor neurons = final common pathway

20. Neuromuscular Junction

21. Many terminal branches on motor neuron (one can innervate many muscle cells) Axon terminal = “bouton” (“button”) Motor end plate Neuromuscular junction analogous to synapse Usually, each action potential in motor neuron -> one action potential in muscle cell

22. Toxins Black widow venom (releases ACh from cholinergic neurons) Botulinum toxin (“botox”; blocks ACh release from boutons) Curare (competes with ACh for cholinergic receptors) Cholinesterase inhibitors (many insecticides, chemical warfare agents). Prevent muscles from relaxing