A&P Chapter 14 Flashcards
Senses
process by which the brain perceives info about the body and surrounding.
Senses
process by which the brain perceives info about the body and surrounding.
general sense
- receptors distributed across the body
- divided into somatic and visceral
Special sense
- limited distribution
- specialized structures
smell, hearing,taste, sight.
sensory receptor
classified by location
cutaneous receptors
- associated with the skin
- external environment
- temp, pressure, touch
viscerorecptors
- viscera and internal
- internal environment
pain, pressure, stretch
proprioreceptors
- joints, tendons, and connective tissue
- body position, movement, muscle stretch.
where your extremities are
mechanoreceptors
- compression, bending, stretching, pinching, or rubbing
- touch tickle, itch, balance, hearing
Chemoreceptors
- chemicals ( liquid or gas)
- smell and taste
Thermoreceptors
- changes in temperature
Photoreceptors
- light and color
- vision
nocireceptors ( pain receptors)
- painful mechanical, chemical, heat
Free nerve endings
- pain, tickle, temperature, movement, and position
general sense
- receptors distributed across the body
- divided into somatic and visceral
Special sense
- limited distribution
- specialized structures
smell, hearing,taste, sight.
sensory receptor
classified by location
Ruffini end organs
pressure and continuous touch
viscerorecptors
- viscera and internal
- internal environment
pain, pressure, stretch
golgi tendon organs
- tendon tension
mechanoreceptors
- compression, bending, stretching, pinching, or rubbing
- touch tickle, itch, balance, hearing
Chemoreceptors
- chemicals ( liquid or gas)
- smell and taste
Thermoreceptors
- changes in temperature
Photoreceptors
- light and color
- vision
nocireceptors ( pain receptors)
- painful mechanical, chemical, heat
Free nerve endings
- pain, tickle, temperature, movement, and position
Merkel disks
- light touch and superficial pressure
Hair follicle receptors
slight bending of the hair and light touch
pacinian corpuscles
- deep pressure, vibration, and position
muscle spindle
muscle length (stretch reflex)
golgi tendon organs
- tendon tension
Muscle spindles
- 3-10 specialized skeletal muscle cells
- provide info about length of muscles
- involved in stretch reflex
Association areas
- areas adjacent to primary sensory areas
- involved in recognition of stimuli
primary receptors
- conduct action potential in response to receptor potential
Secondary receptors
- have no axons
- release neurotransmitters
Adaption
-decreases sensitivity to continued stimuli
getting dressed
tonic receptors (slow adapting)
- generate action potential as long as there’s a stimuli
Phasic receptors(rapidly adapting)
- sensitive to changes in stimuli
2 major ascending tracts
- spinothalamoc tract
- dorsal column/ medial-lemniscal
Spinoolivary
contribute to coordination of movement associated with balance
spinotectal
involved in reflexes that turn the eyes and the head toward point of cutaneous stimulation
primary sensory areas
- where sensations are perceived
- area must be intact for proper sensation
primary somatic sensory cortex
- occupies postcentral gyrus
- receives general sensory input
- organization is inverted
Two divisions
- somatic sensory association area
- visual association area
primary motor cortex
- controls most voluntary movement
- function arranged topographically
- muscle groups with many motor units represented by large areas
premotor area
staging area for motor function organization
prefrontal area
planning and motivation of movements
primates only
Motor tracts
- descending pathways carry signals from brain
- 2 groups
- direct pathways( pyramidal): maintaining muscle tone, speed and precision (mammal specific)
Indirect pathways
- less precise control
- primitive, crude movement
Spinocerebellum
- consists of vermis and lateral hemisphere
- aids in fine motor coordination
- comparator function
Cerebrocerebellum
- rapid complex movements
- planning and practice
playing piano, golf swing (10,000 hr concept)
Reticular activation system
- regulates cyclical motor functions
- affected by visual and acoustic stimuli
- can trigger alertness
- lack of stimuli can trigger sleep
