Term Test 4 - Senses Flashcards
what does sensation refer to?
raw sensory information activating our sensory receptors, that travels through the brain as action potentials.
what sensory receptors are used for vision?
rods and cones.
what does transduction refer to?
physical information from the environment being turned into electrical signals.
what does perception refer to?
your interpretation, selection, and organization of that sensory input.
how is perception constructed?
perception is constructed by prior experience, attention, and your expectations of the world.
sensation is determined by the nature of the_____?
sense receptor.
what is a phosphene?
a ring or spot of light produced by pressure on the eyeball or direct stimulation of the visual system other than by light.
what is cross-modal perception?
this refers to the combination of senses that can lead to different perceptual experiences.
what is the McGurk effect?
visual processing influences auditory processing. This shows us that sensation and perception differ.
Based on our visual input, our perception can be influenced, even if the sensory input has not changed.
what is synesthesia?
condition in which people experience consistent cross-modal sensations.
what is graphme-color synesthesia?
when you associate colours to numbers even if the numbers are printed in black in white.
what is lexical-taste synesthesia?
people with this type of condition can have a taste sensation based on a word.
what is synesthesia an example of?
this is an example of how sensation and perception do not always line up.
what is psychophysics?
psychophysics is the study of how physical stimuli are translated into psychological experience.
what is a threshold?
a threshold refers to how strong a stimulus has to be in order for us to detect it.
what is an absolute threshold?
the stimulus intensity in which the stimulus is detected 50% of the time when the stimulus is actually present.
what is the JND?
the smallest difference in the amount of stimulation that a specific sense can detect.
what is an example of a JND?
if you are holding two objects, the smallest difference in weight is the JND.
what is Weber’s law?
the size of JND is a constant proportion to the size of the initial stimulus.
what does sensitivity refer to?
how responsive we are to faint stimuli.
what does acuity refer to?
how well we can distinguish two very similar stimuli.
what is the SDT?
this theory states that all decision making happens in the presence of noise.
what are two factors in the SDT?
expectations and strength of the stimuli are important in decision making.
what are the correct decisions?
HIT and CR.
what are the incorrect decisions?
FA and MISS.
if you have expectations for a stimulus, is your threshold higher or lower?
lower.
what does the signal refer to?
the useful, relevant information.
what does the noise refer to?
the irrelevant, or false information.
what is the criterion?
the criterion helps you determine how likely you are to say the signal is present.
what is a liberal criterion?
a liberal criterion (lower threshold) makes you say yes more often and increases your HIT and FA.
what is a conservative criterion?
more likely to say no, and you have an increase in CR and MISS.
what properties of light are we interested in?
wavelength, amplitude, and purity
what does wavelength refer to?
the wavelength is the distance between the two peaks, and it determines the colour we see.
what does a longer wavelength refer to?
we will see colours closer to red.
what does amplitude refer to?
the vertical distance of the wave, which determines the brightness of the light we see.
what does purity refer to?
purity refers to the degree to which a light source is emitting just one wavelength or a mixture of wavelengths.
what does purity tell us?
it tells us how many colours (saturation) we will see.
what are the parts of the eye we discussed?
the cornea, iris, and pupil.
what does the cornea do?
the cornea is the protective layer that bends light and sends it through the pupil.
what does the pupil do?
the pupil dilates and constricts in order to determine how much light to let in.
in dark conditions does the pupil get smaller or larger?
in dark conditions, the pupil dilates and becomes larger to increase the amount of light in.
what does the iris do?
the iris is the coloured ring in the eye that helps control the constriction and dilation of their pupil.
what happens to those individuals born without an iris
everything is constantly way too bright.
what is the purpose of the lens?
Muscles in the lens help you adjust your focus to things that are near and far.
is nearsightedness and farsightedness caused by damage to the muscles?
no, it is not. In some ae related changes, it may be due to the muscles.
what comes after the lens?
after the lens, you have your eyeball. The light travels through the cornea, pupil, and then lens to get reflected at the back of your eye, where the retina is located.
what is located at the retina?
the rods and cones.
what is the fovea?
located at the retina, the fovea also known as the focal point is the area where your vision is the clearest.
what is the optic disk?
the optic disk is where the optic nerve exits the back of the eyeball. At this spot, there is a blind spot, because there are no light receptors.
do we notice the blind spot?
no, because our perception helps us fill in the gaps.
what is nearsightedness?
nearsightedness, also known as myopia is a condition where the eye is longer than it should be and the focal point of the eye is in front of the retina.
how do we fix this condition?
concave lenses.
what is farsightedness?
farsightedness, also known as hyperopia, is when the eye is too short. In this condition, the focal point is behind the eye.
how do we fix this condition?
convex lenses.
what do rods and cones do?
the rods and cones pick up signals from light. When the light hits the back of the retina, it is projected forward and out to your optic nerve.
rods are sensitive to?
light and dark.