Ch.4 Sensation and perception Flashcards
Sensation
Process of receiving stimulus energies from the external environment
Perception
Process of organizing and interpreting sensory information.
Bottom-up
initiated by sensory input, outside world’s influence on perception
Top-Down
initiated by cognitive processing, internal/mental world’s influence on perception
Sensory receptors
specialized cells that selectively detect and transmit sensory info to the brain
-send signals via distinct neural ways.
Absolute threshold
minimum amount of stimulus
- an organism can detect 50% of the rime
Difference threshold
How much stimulus change is necessary for detection
-just noticeable difference
Signal detection theory
did i detect something?
hit- a stimulus is present and detection of stimulus
miss- stimulus us present no detection
false alarm- false detection of stimulus
correct rejection- no stimulus present and does not detect one
Attention
focusing awareness on a narrowed aspect of the environment
Cocktail party phenomenon
selectively paying attention within a loud setting ( certain things in the environment grab attention more than others)
Sensory adaptation
the process by which our brain cells become less sensitive to constant stimuli that are picked up by our senses.
photoreceptors retina
rods
sensitive to dim light, but not color
function well in low illumination
humans have about 120 million rods
retina (cones) continued
respond to colors
operate best under high illumination
humans have about 6 million cones
fovea- densely populated with cones vital to many visual tasks
Optic chiasm
the part of the brain where the optic nerves cross and is therefore of primary importance to the visual pathway
(optic nerves cross so it is important for vision)
Trichromatic theory of color
three categories of receptors
green, blue, and red cones
Opponent process theory (afterimages)
sensation remains after the stimulus is removed
Cochlea
Located in the inner ear through which sound waves travel and trigger nerve impulses.
Auditory nerve
a nerve connecting the inner ear with the brain and carrying nerve impulses concerned with hearing and balance
Brain stem
the part of the brain that connects the cerebrum with the spinal cord
temporal lobe
most commonly associated with processing auditory information and with the encoding of memory.
Localization of sound (intensity)
The sound waves of the bark hit the right ear first and are more intense on that side compared to the left
localization of sounds (timing)
The brain works out sound direction by comparing the times of when sound reaches the left versus the right ear.
Pathway of auditory information
cochlea-> auditory nerve->brain stem->temporal lobe
Pathway (touch)
receptors-> spinal chord->thalamus->somatosensory cortex of parietal lobe
Thermoreceptors
Detect changes in temperature to warn about the danger of the temperature
Pain (role of endorphins)
Your brain releases endorphins to block the nerve cells that receive the pain signals
Papillae
Papillae are the little bumps on the top of your tongue and they contain your taste buds
Taste buds
nerve endings that are located on the tongue and back of the throat and are responsible for our sensation of taste.
6 taste qualities
sweet, sour, salty, pungent, bitter and astringent.
Olfatory bulb
structure located in the forebrain of vertebrates that receives neural input about odours detected by cells in the nasal cavity
Olfatory nerve
This nerve enables your sense of smell and human olfaction is unique in its ability to cue the emotional aspects of autobiographical memory
Kinesthetic
he senses of position and movement of the body
Vestibular sense
provides the sense of balance
