Psychology ch.3

Perceptual Constancies

Acquired through experience; creates stability - Size Constancy - Color Constancy - Brightness Constancy - Shape Constanc

Optic Nerve

Axons of ganglion neurons form optic nerve - Conducts sensory input to brain (occipital lobe)

inner ear

Cochlea • Basilar membrane • Organ of Corti

Complementary Colors

Colors across from one another on color wheel - Mix complementary colors = gray

prostagandis

Facilitate transmission of pain message - Heighten circulation to injured area (inflammation) - Pain-relieving drugs inhibit production of prostaglandins - Emotional response and response to stress affect degree of pain

outer ear

Funnels sound waves to the eardrum

loudness

Height (amplitude) of sound waves - Expressed in decibels (dB)

Retina

Light Sensitive Surface,Photoreceptors - Rods, Cones, Bipolar and ganglion cell

locating sounds

Loudness and sequence in which sounds reach the ear provide cues - May turn head to clarify information

Just noticeable difference (JND)

Minimum difference a person can detect

Difference Threshold

Minimum difference in magnitude of two stimuli required to tell them apart - Detected 50% of the time

Desensitization

Negative adaptation - Process by which we become less sensitive to stimuli that remains the same

Sensitive areas of the body

Nerve endings are more densely packed - More sensory cortex is devoted to perception of sensations in those areas

gate theory of pain

Nervous system can only process a limited amount of stimulation - Rubbing the pained area competes for neural attention - Closes the "gate" on pain messages to the brain

pain

Nociceptors in skin are stimulated - Pain is usually sharpest where nerve endings are densely packed - Pain can be felt deep within body - No nerve endings for pain in the brain

Trichromat

Normal color vision

smell

Odors trigger receptor neurons in olfactory membrane

Subliminal Stimulation

Sensory stimulation that is below a person's absolute threshold for conscious perception - Visual stimuli flashed too briefly to be processed - Auditory stimuli played a volume too low to consciously hear or played backward

- Active touching

Skin sensory receptors fire when skin surface is touched

Sound

Sound waves require a medium; air or water • Sound waves compress and expand molecules of the medium, creating vibrations - A single cycle of compression and expansion is one wave of sound

Weber's constant

Standard of difference

Signal-Detection Theory

Stimulus characteristics and psychological factors interact to influence whether a stimulus is detected.

taste

Taste is sensed through taste cells - Receptor neurons on taste buds

Opponent-Process Theory

Three types of color receptors • Respond to red or green, blue or yellow, or light or dark • Cannot respond to both at simultaneously

Perception of Motion

Visual perception of motion is based on change of position relative to other objects

Absolute Threshold

Weakest amount of a stimulus that can be distinguished from no stimulus at all - Detected 50% of the time

Spectrum of electromagnetic energy

Within visible light, color is determined by wavelength • The height of a wave gives us it's intensity (brightness). • The length of the wave gives us it's hue (color). • ROY G BIV • The longer the wave the more red. • The shorter the wavelength the more violet.

the human ear

is sensitive to sound waves with frequencies of 20 to 20,000 cycles per second

Iris

muscle; colored part of the eye

Pupil

opening in the iris • Sensitive to light and emotion

Perception

process by which sensations are organized and interpreted to form an inner representation of the world.

odors

sample molecules of substances in the air

sensation

stimulation of sensory receptors and transmission of sensory information to the central nervous system.

Cornea

transparent eye cover

Gestalt Rules of Perceptual Organization (6)

• Figure-Ground • Proximity • Similarity • Continuity • Closure • Common Fate

Sensation/perception

• Sensation is a mechanical process • Perception is an active process - Involves knowledge, expectations, and motivations

Lens

- Changes in thickness for focusing - Image is projected onto retina

Sensorineural deafness

- Damage to inner ear or auditory nerve

conduct deafness

- Damage to middle ear - Hearing aids can help

middle ear

- Eardrum, hammer, anvil and stirrup - Acts as an amplifier - Oval window - Round window

pitch

- Frequency (# of cycles per second) - Expressed in hertz (Hz) - Pitch of women's voice is higher than men's

Müller-Lyer Illusion

- Interpret length of lines based on experience

Cones

- Most densely packed in center of retina (fovea) - Provide color vision

Dichromat

- Partial color blindness - Difficulty in discriminating between two colors - More common in males (sex linked trait)

Monocular Cues

- Perspective - Relative size - Clearness - Overlapping - Shadows - Texture gradient - Motion parallax

volley principle

- Pitch is discriminated through alternate firing of neurons

Illusions of movement

- Stroboscopic motion

four primary taste quality

- Sweet, sour, salty and bitter - Umami (fifth basic taste) - savory

Trichromatic Theory

- Three types of cones • Respond to red, green, or blue

Monochromat

- Totally color blind

the ear

- capture sound waves - vibrate in sympathy with them - transmit auditory information to the brain

phantom limb pain

2 out of 3 combat veterans with amputated limbs report phantom limb pain - May involve activation of nerves in the stump of missing limb - May also involve reorganization of motor and somatosensory cortex

Hering-Helmholtz Illusion

Perceive drawing as three-dimensional

Afterimage

Persistent sensations of color are followed by perception of the complementary color when the first color is removed

• Light is the source of all colors

Pigments reflect and absorb light selectively

place theory

Pitch is sensed according to place that vibrates

frequency theory

Pitch perceived on stimulation of impulses that match the frequency of the sound

Sensitization

Positive adaptation - Process by which we become more sensitive to stimuli of low magnitude

Adaptation to bright light

Process occurs within a minute or so

Dark adaptation

Process of adjusting to lower lighting • Cones reach maximum adaptation in about 10 minutes • Rods continue to adapt up to 45 minutes

Visual Perception

Process used to organize sensory impressions caused by the light that strikes our eyes

Rods

Provide vision in black and white - More sensitive to dim light than cones

temperature

Receptors are located just beneath the skin - Skin temperature increases - receptors for warmth fire - Skin temperature decreases - receptors for cold fire

perception of loudness

Related to number of receptor neurons on the organ of Corti - Sounds are perceived as louder when more sensory neurons fire

Binocular Cues

Retinal disparity - Convergence

Kinesthesis

Sense that informs you about the position and motion of your body - Sensory information is sent to the brain from sensory organs in joints, tendons and muscles • Housed mainly in semicircular canals in your ears • Monitor your body's motion and position in relation to gravit