**a&p 2 Chap 16

Front 1

Sensory modalities and 2 types

Back 1

Each unique type of sensation

General Senses - touch, proprioception, pain, heat, pressure, movement

Special senses - Touch, taste, hear, smell, equilibrium

Front 2

Sensory neurons that conduct impulses from PNS into the CNS

Back 2

First-order neurons

Front 3

Generator Potential

Back 3

Graded potential produced by free nerve endings, encapsulated nerve endings, and receptive part of olfactory to trigger action potentials

Front 4

Receptor Potential

Back 4

Graded potential caused by separate cells in the ear, gustatory, and eyes and triggers PSPs post synaptic potentials

Front 5

Nociceptors

Back 5

Free nerve endings that respond to pain found everywhere except the brain

Has very little adaptation

Front 6

Osmoreceptors

Back 6

Receptors that detect osmotic pressure of body fluids

Front 7

Tactile sensations

Back 7

Touch, pressure, vibration, itch and tickle

Front 8

Two types of rapidly adapting touch receptors

Back 8

Meissner corpuscles (corpuscles of touch) for fine touch in dermal papillae

Hair root plexuses for crude touch in hair follicles

Front 9

Two types of slowly adapting touch receptors

Back 9

Merkel discs in stratum basale for fine touch

Ruffini corpuscles in dermis, ligaments and tendons for stretch

Front 10

Receptors for pressure & vibration

Back 10

Corpuscles of touch (meissener), type I mechanoreceptors (Merkel disk) & lamellated or pacinian corpuscle are all rapidly adapting

Front 11

Cold receptors

Back 11

More plentyful of the thermal receptors and connect to myelinated A fibers

Front 12

Warm Receptors

Back 12

Less plentyful of the thermal receptors and connect to unmyelinated C fibers

Front 13

Kinesthesia

Back 13

Perception of body movements

Front 14

Muscle Spindles

Back 14

Proprioceptors in skeletal muscles & sets muscle tone

Found in all skeletal muscle except the inner ear & monitors muscle length

Front 15

Intrafusal muscle fibers

Back 15

specialized muscle fibers within a muscle spindle that have sensory nerve endings wrapped around it

Front 16

Gamma motor neurons

Back 16

Adjusts tension in a muscle spindle to variations in muscle length to keep intrafusal fibers taur and maintain spindle sensitivity

More frequency of impulses in gamma motor neuron, spindle becomes more sensitive to stretching in midregion

Front 17

Extrafusal muscle fibers

Back 17

Ordinary skeletal muscle that are supplied by large diameter A fibers called alpha motor neurons that causes contraction or relaxation of skeletal muscle

Front 18

Alpha motor neurons

Back 18

Neurons with cell bodies in anterior gray horn and activates extrafusal muscle fibers

Front 19

Tendon Organs

Back 19

Found in tendons and relaxes muscle during extreme tension

Front 20

Joing Kinesthetic Receptors

Back 20

Monitors & controls pressure in joints

Front 21

First, Second, Third order Neurons & paths

Back 21

Conduct impulses from somatic receptors into brain stem or spinal cord

Decussate in brain stem or spinal cord and into the thalamus

Conducts impulses from thalamus to primary somatosensory area on same side

Paths to cortex are
- Posterior colum-medial lemniscus pathway
- Anterolatero spinothalamic pathway

-Somatic sensory impulses get to cerebellum by spinocerebellar tracts

Front 22

Posterior column-medial lemniscus pathway & Components

Back 22

Pathway for nerve impulses for proprioception and tactile sensations

Posterior columns composed of gracile fasciculus and cuneate fasciculus

Medial lemniscus after deccusation in medulla

Front 23

Stereognosis

Back 23

Ability to recognize size, shape and texture of object by touching it

Front 24

Weight discrimination is mediated by what sensasion

Back 24

Proprioception

Front 25

Lateral spinothalamic tract

Back 25

Conveys pain and temperature

Front 26

Anterior spinothalamic tract

Back 26

Conveys tickel, itch, crude touch, and pressure

Front 27

2 major proprioceptive routes

Back 27

Posterior and Anterior spinocerebellar tracts critical for posture, balance, and coordination

Front 28

Syphilis cause & symptoms

Back 28

Treponema Pallidum

Damage to posterior portion of spinal cord resulting in loss of sensations & proprioception

Front 29

Lower motor neurons (LMNs)

Back 29

Neurons that extend from brain stem and spinal cord to innverate skeletal muscle

Front 30

Somatic Motor pathways

Back 30

Provides input to lower motor neurons
- Local circuit neurons
- Upper motor neurons
- Basal ganglia neurons
- Cerebellar neurons

Front 31

Two types of paralysis

Back 31

Flaccid paralysis caused by damage to lower motor neurons on same side of body

Spastic paralysis from damage of upper motor neurons in cerebral cortex causes paralysis on opposite side of body & reflexes are exaggerated with increase muscle tone

Front 32

Direct & indirect motor pathways

Back 32

Two different ways that upper motor neurons extend from brain to lower motor neurons

Indirect inputs info to brain stem which receives signals from other parts

Front 33

Direct motor pathways

Back 33

-Lateral corticospinal tract for precise agile movements
-Anterior corticospinal tract for movements in neck, trunk,aka axial skeleton
-Corticobulbar tract controls skeletal muscles in the head

Front 34

Amyotrophic Lateral Sclerosis (ALS)

Back 34

a.k.a Lou Gehrig's disease that causes progressive muscle weakness and atrophy due to attacks on motor neurons

Front 35

Extrapyramidal pathways

Back 35

a.k.a Indirect motor pathways
Rubrospinal
Tectospinal
Vestibulospinal
Lateral & Medial reticulospinal tracts

Front 36

Chorea

Back 36

key sign of HD involving rapid jerky movements involuntarilly

Front 37

Huntington's disease

Back 37

Neurodegenerative disease of the caudate nucleus and putamen with loss of neurons that release GABA & Ach

Front 38

Circadian Rhythm

Back 38

24 hour cycle that humans sleep and awake

Front 39

Reticular Activating System (RAS)

Back 39

functions in arousal and regaining conciousness found for all senses except olfactory

Front 40

Plasticity

Back 40

Capability for change associated with learning

Front 41

Memory consolidation

Back 41

Reinforcement that results from frequent retrieval of a piece of information

Front 42

Long-Term Potentiation (LTP)

Back 42

A phenomenon in which transmission at some synapses within hippocampus is enhanced after a brief period of high frequency stimulation