1. Discriminative Pain
   1. Anterolateral Columns
      1. Course touch
         1. Less localized info from mechanoreceptors to unmyelinated C Fibers -> left insula (+ feelings)
         2. Anterolateral column lesions here = no emotion assoc w/ touch
      2. Temp
         1. Aδ fibers -> cooling C fibers -> heat
         2. relayed via small (un) & myelinated free nerve endings to sensory cortex
      3. Pain
         1. SIDE NOTE: Spinothalamic Pain -> immediate sharp, localized sensation Spinolimbic Pain -> dull unlocalized pain
         2. Lateral Pain Syst
            1. Fast and Localized
            2. 1st Order Neuron: ->info to dorsal horn of sp cord
            3. Primary Neuron: (myelinated Aδ fiber) sends mechanical/thermal peripheral info to sp cord
            4. Peripheral Axon: impulse ->cell body -> dorsal root ganglion central axon: branches into dorsolateral tract levels -> enters/ends at lamina I, II, OR V of dorsal horn primary neuron: releases NT glutamate
            5. 2nd Order Neuron: -> cross sp. cord midline -> thalamus
            6. Cell Body: in lamina I, II or V of dorsal horn Axon: crosses: anterior white commissure midline -> spinothalamic tract (most end VPL nucleus of thalamus) -> thalamus
            7. 3rd Order Neuron: projects from thalamus -> cerebral cortex
            8. starts at VPL of nucleus ->primary/secondary sensory cortex
            9. SIDE NOTE: lesion in VPL nucleus = inability to localize pain but emot is still there
         3. Systems comparison (purple and dark blue)
            1. BOTH Axons: second order axons cross midline 2nd Order Neuron: ends in VPL nucleus of thalamus 3rd Order Neurons: project -> thalamus ->primary sensory cortex -> info localized
            2. Dorsal Column-Medial Lemniscal Path
            3. axons cross in medulla
            4. Spinothalamic Path
            5. axons cross in sp cord prior to ascent of axon
         4. Fast Pain/Temp Info: Face
            1. 1st Order: travels via trigeminal nerve -> pons -> medulla -> upper cervcal cord -> descending tract of trigem. nerve -> synapse in sp cord of " "
            2. 2nd Order Fibers: ascend trigem. lemniscus -> VPM nucleus of thalamus
            3. 3rd Order Neurons: -> cerebral cortex
            4. Side Note: Analgesia: no pain w/ normally painful stimuli Crossed Analgesia: single lesion = pain sensation lost on face ipsilateral to lesion/opposite side of body
         5. Pain: Fast vs Slow
            1. C Fibers: small unmyelinated axons = feel pain longer; conducts 0.5 sec Aδ Fibers: conduct 0.3 sec (faster)
2. Divergent Pathways
   1. Medial Pain System
      1. activity evokes: affective, motivational, withdrawal, arousal & autonomic responses
         1. 1st Order Neuron: unmyelinated C FIBER
            1. efferent nerves: PNS -> cell body -> dorsal root ganglion -> central axon -> sp. cord -> interneurons in lamina I, II, V dorsal horn
            2. Lamina I: marginal layer Lamina II: substantia gelatinosa NT: substance P
            3. interneurons-> cell bodies of ascending projection neurons-> lamina V and VIII
            4. Ascending Projection Neurons
            5. Spinomesencephalic
            6. Relay to: superior colliculus/periaqueductal gray Regulates: turning eyes/head to source of pain & activates descending tracts (control pain)
            7. Spinoreticular
            8. Relay to: brainstem Reticular Formation RF regulates: attention, arousal, sleep/wake cycle Cont Relay to: axons of midline/intralaminar nuclei in thalamus
            9. Spinolimbic
            10. Relay: SLOW pain info to medial/intralaminar nuclei in thalamus Cont Relay: anterior cingulate cortex, insula, amygdala, dorsolateral prefrontal cortex
            11. Projects to Cerebral Cortex to REGULATE: emotions, sensory integration, personality, mvm't & Projects to: Amygdala, Hypothalams
            12. SIDE NOTE: pain tends to resonate throughout gen location as opposed to a specific point -> automatic mvmt, & autonomic/emot response to hurtful stimuli
            13. Activity here = arousal, withdrawal, autonomic, effective responses to pain
      2. Trigeminoreticulolimbic Pathway
      3. Temp
         1. Relay: reticular formation, nuclei of thalamus (non-specific), subcortical nuclei, hypothalamus Via: phylogenetically older pathways
      4. Activity here = thalamus and basal ganglia detect slow pain
   2. Unconscious Relay Tracts to Cerebellum
      1. Posterior Spinocerebellar Pathway
         1. Transmits: info of lower 1/2 body/legs
         2. 1st Order Neuron: dorsal column of thoracic sp. cord -> synapse dorsal grey matter aka nucleus dorsalis (T1-L2)
         3. 2nd Order Axons: project to cereb. cortex via inferior peduncle
      2. Cuneocerebellar Pathway
         1. 1st Order Neuron: primary afferents of arm/upper 1/2 body Central Axons: travel -> lower medulla posterior columns 1 and 2 synapse meet: lateral cuneate nucleus (medulla) 2nd Order Neurons: form cuneocereb. tract (enter: ipsi. inferior cereb. peduncle / *end: cerebellar cortex) Target Neurons: posterior spinocerebellar/cuneocerebellar tracts in *
   3. Internal Feedback Tracts
      1. Anterior Spinocerebellar T.
         1. Transmits: thoracolumbar sp cord info aka lower limb info -> lat/ventr. horn cell bodies->go to opp side -> ascend contralat. ant. spinocerebellar tract -> midbrain -> superior cerebellar peduncle -> cerebellum -> produce lower limb mvmt
      2. Rostrospinocerebellar T
         1. Transmits: cervical sp cord info -> inf/sup peduncles -> ipsilat cerebellum -> produce lower limb mvmt
      3. SIDE NOTE: job is to convey descending motor info cerebellum first to make corrections to intended mvm't
      4. SIDE NOTE: info received from proprioceptors, sp. interneurons & desc. motor path's.
      5. Activity Here = control motor activity by commands to neurons via interneurons and convey info of sp. reflex circuit act
3. Spinocerebellar Tract vs. Cerebellar Lesions
   1. coord of mvmt w/out vision = damage to SPC Tract
4. Floating Topic