Sensation and Perception – Lecture Notes Review (Introduction to Psychology 9/10/21)

A comprehensive set of Q&A flashcards covering sensation, perception, eye/ear anatomy, color and pitch theories, senses (taste, smell, somesthetic), perceptual constancies, Gestalt principles, depth cues, and perceptual illusions.

What is sensation?

The activation of receptors in the various sense organs.

What are sensory receptors?

Specialized forms of neurons that detect sensory information.

Which sense organs are involved in sensation?

Eyes, ears, nose, skin, and taste buds.

What is the Just Noticeable Difference (JND)?

The smallest difference between two stimuli that is detectable 50 percent of the time.

What is the Absolute Threshold?

The smallest amount of energy needed for a person to consciously detect a stimulus 50 percent of the time.

What are subliminal stimuli?

Stimuli that are below the level of conscious awareness but can be strong enough to activate receptors.

What is subliminal perception?

The process by which subliminal stimuli can influence the unconscious mind and behavior.

What is habituation?

The tendency of the brain to stop attending to constant, unchanging information.

What is sensory adaptation?

The tendency of sensory receptor cells to become less responsive to a stimulus that is unchanging.

What are microsaccades?

Tiny, constant eye movements that prevent sensory adaptation to visual stimuli and are not usually consciously noticed.

How is brightness determined?

Brightness is determined by the amplitude of the light wave—the higher the amplitude, the brighter.

How is color (hue) determined?

Color is determined by wavelength; long wavelengths are red, short wavelengths are blue.

What does saturation refer to in color?

The purity of the color; mixing in black or gray reduces saturation.

What is the cornea?

The clear membrane that covers the eye and focuses most of the light entering the eye.

What is the pupil?

The opening through which light enters the interior of the eye.

What is the iris?

The colored muscle that controls the size of the pupil and helps focus the image.

What is the lens?

A clear structure behind the iris that finishes the focusing process begun by the cornea.

What is the aqueous humor?

Clear, watery fluid in the anterior part of the eye that nourishes the eye.

What is the vitreous humor?

Jelly-like fluid that nourishes the eye and gives it shape.

What are rods?

Retinal receptors responsible for noncolor vision in low light; located at the back of the retina.

What are cones?

Retinal receptors responsible for color vision and sharpness of vision; located at the back of the retina.

What does the phrase 'rods outnumber cones by about 20 to 1' mean?

There are roughly twenty rods for every cone in the retina, affecting vision under low light.

What is the blind spot?

The area in the retina where the axons exit the retina to form the optic nerve; insensitive to light.

What is visual accommodation?

The change in the thickness of the lens as the eye focuses on near or far objects.

What is the vitreous humor?

Jelly-like fluid that nourishes the eye and helps give it shape.

What is dark adaptation?

The recovery of the eye's sensitivity to visual stimuli in darkness after exposure to bright lights.

What is light adaptation?

The recovery of the eye's sensitivity to visual stimuli in light after exposure to darkness.

What is the Trichromatic Theory?

The theory of color vision proposing three types of cones: red, blue, and green.

What are afterimages?

Images that persist briefly after the original stimulus is removed.

What is the Opponent-Process Theory?

The theory of color vision proposing four primary colors arranged in red-green and blue-yellow pairs; supported by the LGN.

What are Protanopia and Deuteranopia?

Protanopia: lack of functioning red cones. Deuteranopia: lack of functioning green cones.

What is Tritanopia?

Lack of functioning blue cones.

What is monochrome color blindness?

Color blindness where there are no functioning cones or color vision is absent.

What is the Ishihara Color Test used for?

A test to assess color vision deficiencies using dot patterns.

What is meant by the relation between wavelength and sound Pitch?

Wavelength in sound is interpreted as frequency or pitch.

What does amplitude in sound correspond to?

Amplitude is interpreted as volume (loudness) of a sound.

What does purity (timbre) refer to in sound?

Purity is interpreted as timbre, the richness of the tone.

What does Hz measure?

Hertz, the unit of frequency (cycles per second).

What is the auditory canal?

The short tunnel from the pinna to the eardrum that channels sound toward the eardrum.

What is the eardrum (tympanic membrane)?

Thin skin that vibrates when struck by sound waves, triggering the middle ear bones.

What are the three middle ear bones and their common names?

Hammer (malleus), Anvil (incus), Stirrup (stapes).

What is the cochlea?

A snail-shaped inner ear structure filled with fluid that contains the organ of Corti and hair cells.

What is the Organ of Corti?

The structure in the cochlea that contains hair cells which transduce sound into neural signals.

What is the auditory nerve?

A bundle of axons from the hair cells that carries auditory signals to the brain.

What is Place Theory of pitch?

Different pitches are experienced by stimulation of hair cells at different locations along the organ of Corti.

What is Frequency Theory of pitch?

Pitch is related to the speed of vibration of the basilar membrane; high frequencies create rapid vibrations.

What is the Volley Principle?

For frequencies above about 100 Hz, auditory neurons fire in a volley pattern to encode pitch.

What is conduction hearing impairment?

Damage to the eardrum or middle ear bones that prevents sound from being conducted to the inner ear.

What is nerve (sensorineural) hearing impairment?

Damage to the inner ear or to the auditory pathways and cortical areas of the brain.

What is a Cochlear Implant?

A device with a microphone, a speech processor, transmitter/receiver, and electrode array that electrically stimulates the auditory nerve to restore hearing.

What are taste buds?

Taste receptor cells in the mouth responsible for the sense of taste (gustation).

What is gustation?

The sense of taste.

What are the five basic tastes?

Sweet, Sour, Salty, Bitter, Umami (savory/brothy).

What is olfaction?

The sense of smell.

What are olfactory bulbs and olfactory receptors?

Olfactory bulbs are brain areas that receive signals from olfactory receptors; there are many olfactory receptors in the nose.

What are somesthetic senses?

The body senses including the skin senses, the kinesthetic sense, and the vestibular senses.

What is the gate-control theory of pain?

Pain signals must pass through a gate in the spinal cord; the gate can be opened or closed to modulate pain.

What is kinesthetic sense?

The sense of the location of body parts in relation to each other and to the ground (proprioception).

What are the vestibular senses?

Senses of movement, balance, and the body’s position; can be affected by motion sickness.

What is perception?

The method by which sensations are interpreted and organized into meaningful experiences.

What is size constancy?

The tendency to interpret an object as always being the same actual size, regardless of distance.

What is shape constancy?

The tendency to perceive the shape of an object as constant even when the retinal image changes.

What is brightness constancy?

The tendency to perceive the apparent brightness of an object as the same despite changes in lighting.

What are Gestalt principles related to organization?

Figure-ground, similarity, proximity, closure, continuity, and common region guide how we group visual elements.

What is a reversible figure?

A visual figure where the figure and ground can switch roles, as in the Necker cube.

What is figure-ground perception?

The tendency to perceive objects as either figure (foreground) or ground (background).

What are similar and proximate cues?

Similarity is grouping similar items; Proximity is grouping items that are close together.

What is closure?

The tendency to complete incomplete figures.

What is continuity?

The tendency to perceive patterns as continuous rather than disrupted.

What is contiguity (common region)?

The tendency to perceive elements in close proximity as part of a group.

What is depth perception?

The ability to perceive the world in three dimensions.

What are monocular cues?

Depth cues that rely on one eye, including linear perspective, relative size, interposition, aerial perspective, texture gradient, motion parallax, and accommodation.

What is linear perspective?

Parallel lines appear to converge in the distance.

What is relative size as a depth cue?

Objects that appear smaller are perceived as farther away.

What is interposition?

An object that blocks part of another is perceived as being in front of the blocked object.

What is aerial perspective?

Distant objects appear hazier due to atmospheric particles.

What is texture gradient?

Textures appear finer as distance increases.

What is motion parallax?

Closer objects appear to move faster than distant objects as you move.

What is accommodation (depth cue)?

The brain uses changes in the lens thickness to judge distance.

What are pictorial depth cues?

Monocular cues used in flat pictures to convey depth, such as linear perspective and texture gradient.

What are binocular cues?

Depth cues that depend on both eyes, including convergence and binocular disparity.

What is convergence in depth perception?

The rotation of the eyes to focus on a close object; more convergence for near objects.

What is binocular disparity?

The difference in images between the two eyes; greater for near objects.

What is the Herman grid illusion attributed to?

A perceptual illusion possibly due to responses in the primary visual cortex.

What is the Müller-Lyer illusion?

A line length illusion where lines of equal length appear different due to arrow-like corners.

What is the Moon illusion?

The moon on the horizon appears larger than when it is high in the sky.

What is autokinetic illusion?

A stationary light in a dark room appears to move due to lack of surrounding cues.

What is stroboscopic motion?

A rapid series of still images can create the impression of motion.

What is the phi phenomenon?

Lights turned on in sequence seem to move.

What is Rotating Snakes illusion?

A static image that appears to move due to eye movements.

What is the Ames Room illusion?

A distorted room that makes people appear to grow or shrink as they move.

What is perceptual set?

The tendency to perceive things a certain way because of prior experience or expectations.

What is top-down processing?

Using preexisting knowledge to organize features into a unified whole.

What is bottom-up processing?

Analyzing smaller features to build up to a complete perception.

What is Necker cube an example of?

An ambiguous figure illustrating figure-ground and depth perception.