Exam 3 Flashcards
What are the five different senses
sight taste smell hearing somatosensory
what kind of stimuli is sight responsive to
light stimuli
what kind of stimuli is taste responsive to
chemical stimuli
what kind of stimuli is smell responsive to
chemical stimuli
what kind of stimuli is hearing responsive to
mechanical stimuli
what kind of stimuli is somatosensory or touch responsive to
mechanical stimuli
The three different kinds of sensory receptors
photoreceptors
chemoreceptors
mechanoreceptors
photoreceptors are associated with
vision; converting light energy into action potentials
mechanoreceptors are associated with
touch, and hearing;converting mechanical energy into action potentials
chemoreceptors are associated with
taste and smell; convert chemical energy into action potentials
the factors influencing receptive field sensitivity
individual receptor sensitivity
density of the receptive field
individual receptor sensitivity
different types of receptors have different sensitivities
ex: rods are more sensitive than cones
stimulus intensity is coded
greater intensity like brighter light or louder noise encoded by a greater discharge rate
ex: with brightness it sends out more action potentials to adjust your eyes to light
stimulus quality is coded
type of the receptor tells the brain the quality/nature of a stimulus
ex: greater quality differentiation for the greater levels received by specific colors receptors
Sensation
the registration of physical stimuli from the environment by the sensory receptors
perception
the subjective experience of sensation
Factors contributing to perception
- nature of sensation
- context in which sensory events take place
- our emotional state
- past experiences and memories
Fovea
the region containing the largest density of photoreceptors; vision is actually sharpest here; makes up 1% of visual field
saccades
moving your eye to move your visual file to focus your fovea
blind spot
a region in your retina with no photoreceptors because of the optic nerve exiting the eye
Are photoreceptors hyper-polarized or depolarized by light
The more light hits the photoreceptor the more Na+ channels is will close, the more HYPERPOLARIZED a cell will be, the less glutamate will be released
rods
light sensitivity, size/shape, their functions, and what numbers of photopigments they contain.
more sensitive to dim light (night vision); only one type of pigment, responsible for night visions, large and cylindrical
cones
light sensitivity, size/shape, their functions, and what numbers of photopigments they contain.
more responsive to bright light; see fine detail and color; smaller; less sensitive; helps with motion; 3 types of light pigment ; smaller and tapered at the end
The different neurons involed in the neural relay for the visual system
photoreceptor -> striate cortex
light enters through the visual system-> photoreceptors (rods and cones)-> action potential from photoreceptors or either high low glutamate->horizontal cells (converge infor from receptors)->bipolar cells->acramine cells (converges from bipolar cells)-> retinal ganglion cells -> to the striate cortex