Chapter 3: The Perceiving Mind [Exam 2] Flashcards
Sensation
Environmental energy that impinges on your sensory receptors.
The process of detecting environmental stimuli arising from the body.
It begins with the interaction between a physical stimulus and our biological sensory systems.
Perception
The process of interpreting sensory information.
What you are conscious of.
Stimulus
Anything that can elicit a reaction from our sensory systems.
Transduction
The translation of incoming sensory information into neural signals.
Distal vs. proximal stimulus.
Sensation > Transduction > Perception.
Sensory Adaptation
The tendency to pay less attention to a non-changing source of stimuli.
Bottom-up Processing
Perception based on building simple input into more complex perceptions.
It is driven by the environment - an “in the moment” observation.
Top-down Processing
A perceptual process in which memory and other cognitive processes are required for interpreting incoming sensory information.
We use knowledge that we have gained from previous experiences.
Absolute Sensory Threshold
The smallest amount of input that can be detected by our sensory systems.
Difference Threshold
The smallest detectable difference between two stimuli - the difference depends on the size of the stimuli being compared.
Method of Limits
Present stimuli in ascending and descending order.
This method is quick, but contains bias due to the previous trials.
Method of Adjustments
Allow the participants to manually adjust stimulus.
It is the fastest method, but it still contains bias.
Method of Constant Stimuli
Present 5-9 different stimuli of different intensities randomly.
This method takes the longest, but is the most effective.
Psychophysics
The study of relationships between the physical qualities of stimuli and the subjective responses they produce.
Gustav Fechner.
Signal Detection
The analysis of sensory and decision-making process in the detection of faint, uncertain stimuli.
It involves two steps: the actual intensity of the stimulus and the individual observer’s criteria for deciding whether the stimulus occurred.
Liberal or conservative responses.
Vision
The sense that allows us to process reflected light.
50% of this is in the cerebral cortex.
Visible light
The radiation emitted from the sun.
Wavelength
The distance between successive peaks of waves.
A shorter wavelength means a higher frequency.
Cornea
The clear surface at the front of the eye that begins the process of directing light to the retina.
Pupil
An opening formed by the iris, where the light enters.
Iris
The colored circular muscle surrounding the pupil. Adjusts the opening of the pupil in response to the amount of light present in the environment and to signals from the autonomous nervous system.
Arousal = dilated pupils.
Relaxation = constricted pupils.
Lens
Clear structure behind the pupil that bends light toward the retina.
Muscles can change shape allowing us to adjust our focus to see near or distant objects.
Retina
Layers of visual processing cells in the back of the eye.
Where the rods and cones are - specialized receptors that transduce light information.
Before light reaches the receptors, it needs to pass through blood vessels and neural layers.
Fovea
The area of the retina that is specialized for highly detailed vision.
Responsible for central vision.
Rod
Photo receptor specialized to detect dim light.
Peripheral vision.
Large and cylindrical.
Cone
A photo receptor in the retina that processes color.
Smaller and tapered.
Optic Nerve
Nerve exiting the retina of the eye.
Optic Chiasm
Point where optic nerves cross the midline.
Optic tracts
Nerve pathways traveling from the optic chaism to the thalamus, hypothalamus, and midbrain.
Trichromacy Theory
Theory of color vision based on the existence of different types of cones for the detection of short, medium and long wavelengths.
Opponent Process Theory
A theory of color vision based on the existence of different types of cones for the detection of short, medium, and long wavelengths.
Short = blue.
Medium = green.
Long = red.
Opponent Process Theory
Suggests that we have a red-green color channel and blue-yellow color channel in which activation of one color in each pair inhibits the other.
Feature Detector
A hypothetical cell that responds to only one specific visual stimulus.
Gestalt Psychology Principles
- We analyze visual input by dividing a scene into figure and ground.
- Proximity - objects that are close together tend to be grouped together.
- Continuity - we assume that points that form smooth lines when connected probably belong together.
- Closure - occurs when people see a complete, unbroken image even when there are gaps in the lines forming the image. “Fill in the blanks.”
- Simplicity - we use the simplest solution to a perceptual problem.
Depth Perception
The ability to use the 2D image projected on the retina to perceive 3D.
Ames room illustrates vulnerabilities in depth perception.
Monocular Cue
A depth cue that requires the use of only one eye.
Binocular Cue
A depth cue that requires the use of only one eye.
Linear Perspective
Apparent convergence of parallel lines at the horizon.
Used in art and graphics.
EX: texture gradients, shading, and occlusion.
Occlusion
Blocking of images of distant objects by closer objects.
Retinal Disparity
Difference between the images projected onto each eye.
An example of binocular cue.
It does not tell us exactly how far away an object is, but it does provide information about the relative distance between two objects.
Nearsightedness
Elongated eyeballs interfering with a person’s vision for distant objects.
Farsightedness
Shortened eyeballs interfering with vision for close-up objects.
Astigmatism
The surface of the cornea is uneven.
Pure Tone
A wave with only one frequency.
These rarely occur in nature.
A tuning fork produces this.
Timbre
A complex tone combining multiple waves.
Different instruments have different timbres.
Infrasound
Refers to frequencies below the range of human hearing.
Less than 20 Hz.
Ultrasound
Refers to the frequencies above the range of human hearing.
Pinna
Outer ear.
The outer visible structure of the ear, collects and focuses sounds, helps us localize sounds above and below our heads.
Sounds collected here are channeled through the auditory canal which ends at the tympanic membrane (eardrum).
Oval Window
Middle ear.
The boundary between the middle and inner ear.
It is bridged by a series of tiny bones - these bones transfer sound energy from the air of the outer and middle ear to the fluid found in the middle ear.
Cochlea
Inner ear.
A fluid-filled cavity embedded in the bone of the skull.
Vestibular Canal
Inner ear.
Vibrations here transmit fluid that travels around to the apex and back to the tympanic canal.
Cochlear Duct
Inner ear.
Separates from the tympanic cancal by the basilar membrane.
Organ of Corti
Inner ear.
On top of the basilar membrane that has many hair cells that transduce sound energy into neural signals.
Auditory Nerve
Inner ear.
Nerve carrying sound information from the cochlea to the brain.
It is formed when the hair cells of the basilar membrane move.
Place Theory
Suggests that the frequency of a sound is correlated with the part of the basilar membrane showing a peak response.
