Chapter 2 Flashcards
Sensation
aligns w/ transduction–> conversion of physical, electromagnetic, & other information from internal & external envts. to electrical signals in the nervous system
Perception
processing of info to make sense of its significance
Sensory receptors
sensory nerves that respond to stimuli
Distal stimuli
in the distance. ex: campfire
Proximal stimuli
in close proximity
Psychophysics
relationship between physical nature of stimuli & sensational/perception they evoke
Sensory ganglia
collection of cell bodies outside the CNS
Projection Areas
areas in the brain that analyze sensory input
Photoreceptors
respond to electromagnetic waves in the visible spectrum (sight)
Hair cells
respond to movement of fluid in the inner ear structures (hearing, rotational, & linear acceleration)
Nociceptors
respond to painful or noxious stimuli (somatosensation)
Thermoreceptors
respond to changes in temperature (thermosensation)
Osmoreceptors
respond to the osmolarity of the blood (water homeostasis)
Olfactory receptors
respond to volatile compounds (smell)
Taste receptors
respond to dissolved compounds (taste)
Absolute threshold
the minimum of stimulus energy that will activate a sensory system
Subliminal perception
refers to the perception of a stimulus below a given stimulus
Threshold of conscious perception
the minimum stimulus energy that will create a signal large enough in size & long enough in duration to be brought into awareness
Difference Threshold
the minimum difference in magnitude between 2 stimuli before one can perceive this difference
-440 Hz vs 441 Hz
Weber’s Law
Just Noticeable Difference (JND) for a stimulus is proportional to the magnitude of the stimulus
Signal Detection Theory
refers to the effects of nonsensory factors, such as experiences, motives, and expectations on perception of stimuli. Accounts for response bias
Adaptation
refers to a decrease or increase in sensitivity to a stimulus
Sclera
exposed portion of eye covered by this thick layer (white of the eye)
Choroid and retinal vessels
eye supplied with these nutrients
Cornea
gathers and filters incoming light
Iris
controls size of pupil, colored part of eye, divided front of the eye into anterior & posterior chamber, 2 muscles: dilator and constrictor pupillae
Lens
refracts incoming light to focus it onto the retina
Aqueous humor
produced by the ciliary body. Nourishes the eye and gives the eye its shape. Drains through the canal of Schlemm
Retina
rods: detect light/dark, contains rhodopsin
cones: color. short/medium/long, in the fovea part of macula
pathway: rods/cones–> bipolar cells–> ganglion cells–> optic nerve
Retinal Disparity
space between eyes; allows for binocular vision and depth
Horizontal & amacrine cells
integrates signals from ganglion cells and performs edge-sharpening
Support
vitreous= inside, sclera/choroid= outside
Parallel Processing
color, form, and motion at same time
Magnocellular cells
motion, high temporal resolution
Parvocellular cells
shape, high spatial resolution
Visual pathway
eye–> optic nerves–> optic chiasm–> optic tracts–> lateral geniculate nucleus-> visual radiations–> visual cortex
Outer ear
pinna (auricle)= channel sound waves to external auditory canal to tympanic membrane (eardrum)
Middle ear
connected to nasal cavity by Eustachian tube. Ossicles: acronym MIS and HAS
Malleus: Hammer
Incus: Anvil
Stapes: Stirrup, footplate of stapes rests in the oval window of cochlea
Inner ear
Bony labyrinth: filled w/ perilymph
Membranous labyrinth: filled w/ endolymph. Consists of cochlea (sound), utricle & sacculae (linear acceleration) & semicircular canals (rotational acceleration and balance)
Projection Areas
superior olive: localizes sounds, in brain stem
inferior colliculus: startle reflex, used by eyes/ears in the vestibulo-ocular reflex which keeps the eyes fixed on a single point as the head rotates
Auditory pathway
cochlea–> vestibulocochlear nerve–> medial geniculate nucleus–> auditory cortex
Place theory
location of hair cell on a basilar membrane determines perception of pitch when that hair cell is vibrated
Smell
detection of volatile or aerosolized chemicals by the olfactory chemoreceptors (olfactory nerves) in the olfactory epithelial. Smell info bypasses the thalamus
Pheromones
chemicals given off by animals that have an effect on social foraging, and sexual behavior
Taste
the detection of dissolved compounds by taste buds in papillae. Sweet/sour/salty/bitter/umamai
Somatosensation
refers to the four touch modalities: pressure, vibration, pain, and temp
Two-point threshold
minimum distance necessary between 2 points of stimulation on the skin such that the points will be felt as two distinct stimuli
Physiological zero
the normal temp of skin to which objects are compared to
Nociceptors
pain reception. Gate theory of pain. Decrease in JND for pain
Kinesthetic reception
proprioception
Top-down processing
the recognition of an object by memories and expectations. Little attention to detail. Uses background knowledge
Bottom-up processing
Details–> whole. Recognition of objects by feature detection. Not influenced by background knowledge
Gestalt principles
proximity, similarity, continuity, closure. All are governed by the law of Pragnanz
