Week 8 Flashcards
(81 cards)
lateral inhibition
inhibiting neighboring signals for sharper contrast of a message
mechanical lateral inhibition
activating neighboring receptors to suppress an area of pain (itch around mosquito bite)
crossing over
right side of the body is controlled by the left side of the brain etc.
inhibitory efferent nerves
block afferent pathways for messages that are deemed unnecessary (ex. don’t feel watch after a certain period of time)
what type of info does the somatosensory nervous system gather?
skin, muscles, joints, bones, tendons
what type of neurons are used in the somatosensory NS?
afferent neurons, 1st design
what types of receptors are used in the somatosensory NS?
thermoreceptors, mechanoreceptors, noiceceptors
what is visual stimuli?
electromagnetic waves
how are electromagnetic waves measured?
photons
do human eyes detect all kinds of electromagnetic waves?
no (ex. UV rays)
what kind of receptors are used in our visual system?
photoreceptors
what kind of adequacy do our photoreceptors have?
low adequacy
what components of the eye help us focus our sight?
cornea and lens
what part of the eye transforms electromagnetic waves?
retina
what version of receptors are in the retina?
2nd version
what is the “problem” with the design of our retinas?
afferent neurons are in front of the receptors, information moves back and forth
why do we have blind spots?
axons of ANs in the retina exit and block receptors
how does the brain make up for blind spots?
makes up what it should look like
what are the types of receptors that encode info in the retina?
rods and cones
rods
seeing shades of grey, more sensitive because they are larger
cones
smaller and less sensitive, seeing “colors”
what type of cones do we have?
red, green and blue
how do we see other colors?
based on the ratio of the cones that are activated, combination of info sent to the CNS by cones causes specific color
what causes color blindness
lack of a certain type of pigment or certain cones behave more like another