Ch. 2: Sensation and Perception Flashcards
(39 cards)
What are sensory receptors?
neurons that respond to stimuli by triggering electrical signals that carry information to the central nervous system
ganglia are collections of neron bodys outside of CNS and will send input to projection areas into the brain
What is absolute threshold?
minimum stimulus energy needed to activate a sensory system
What is the threshold of conscious perception?
level of intensity of a stimulus for te brain to fully process the information
What is a difference threshold?
mimimum difference between two stimli to be percieved as difference
What is Weber’s Law?
the difference threshold for a simulus is proportional to the magnitude of stimulus and proportional to the range of possible stimuli
applying a ratio
What is signal detection theory?
effects of nonsensory factors (experiences, motives, expectations) on peception of stimuli
What is adaptation?
ability to detect a stimulus can change over time
Explain the process of light entering the eye.
- cornea: gathers and focuses light
- anterior chamer
- iris
- posterior chamber
- iris: contains dilator and constrictor pupillae to adjust pupuil, the iris is conitious with the choroid (conective tissue for nutrients) and the ciliary body
- lens: controls refaction of incoming light (ciliary muscle changes lens shape)
- vitereous humor: transparent gel supporting the retina
- retina: converts incoming light to electrical signals
What is accomodation?
ciliary muscpes contract and pull on suspensory ligaments to change to shape of the lens so that it may focus
What is the ciliary body?
produces aqueous humor that drains through the canal of Schlemm
What is the difference between rods and cones?
rods detect light and dark
cones detect color
both are located in the retina
What is the macula and the fovea?
the macula is the central visual field in the retina which has mostly cones with the fovea being the center of the macula which only has cones
What are bipolar cells?
send signals from rods and cones to ganglion cells
What are ganglion cells?
recieve signals form bipolar cells and their axons form the optic nerve
What are nasal/temporal visual fields and retinal fibers?
nasal is inside, nose side and temporal is outside
if the object is in that field, it is detected by the opposite retinal fibers
Explain the visual pathway from the eye to the visual cortex.
- optic nerves
- optic chiasm - nasal fibers from left and right cross paths
- optic tracts
- lateral geniculate nucleus (LGN) in thalamus
- visual cortex in occipital lobe
What is parallel processing?
brain’s ability to analyze information about color, form, motionm=, depth simulatneously
What are parvocellular cells?
detects form
What are magnocellular cells?
detects motion
What are binocular neurons?
detect depth
What is the outer ear?
contains the auricle (outside part of ear) and directs sound waves to tympanic membrane (eardrum) to bibrate at thefrequency of the incoming sound
What is the middle ear?
the middle ear has three small bones called ossicles that transmit and amplify the vibrations to the inner ear
malleus, incus, stapes
What is the inner ear?
the inner ear is a bony labyrinth that has the cochlea, vestibule, and semicircular canals
it is filled tubes and chambers called the membranous layrinth
it is filled with a fluid called the endolympth
there is also a thin layer of fluid called perilymph that transmits vibrations from the outside and cusions inner ear
What does the cochlea do?
detects sound
