Detecting physical energy from the environment and encoding it as neural signals
Selecting, organizing, and interpreting our sensations
What is bottom-up processing?
Sensory analysis that starts at the entry level (begins with sensory receptors)
What is top-down processing?
Constructing perceptions drawing on bottom-up processing and on experience and expectations.
The minimum stimulation needed to detect a particular stimulus 50% of the time
Term for 'below one's absolute threshold for conscious awareness'?
What is priming?
the activation of certain associations, thus predisposing one's perception, memory or responses.
What is the minimum difference between 2 stimuli required for detection 50% percent of the time?
The difference threshold. (a just noticable difference.)
Diminishing sensitivity to an unchanging stimulus
conversion of one form of energy into another. The transforming of stimulus energies, such as sights and sounds, into neural impulses that our brains can interpret.
What is wavelength and intensity, in respect to vision?
- Wavelength= determines hue
- Intensity= influences brightness (determined by wave amplitude)
What are key parts of the eye, and what do they do?
- Cornea: protects eye and bends light to provide focus
- Pupil: light passes through the pupil, a small adjustable opening
- Iris: colored muscle surrounding the pupil; regulates pupil size and amount of light entering eye
- Lens: Focuses incoming rays into image on eye's light-sensitive back surface
- Retina: Light-sensitive inner surface
- Fovea: cones in eye cluster around it; retina's area of central focus
Process by which the eye's lens changes shape to focus on near/far objects on the retina
2 key parts of the retina:
- Rods: detect black, white, and gray; necessary for peripheral/twilight vision
- Cones: function in daylight/well-lit conditions
What is the optic nerve?
The nerve that carries neural impulses from the eye to the brain.
What is parallel processing?
The brain constructs perception by doing several things at once (dividing visual scene into color, depth, etc. working on each aspect simultaneously)
What is amplitude and frequency, in respect to hearing?
- Amplitude: strength of soundwaves= loudness
- Frequency: Wavelength variation= pitch
What are key parts to the ear?
- Eardrum: membrane that vibrates with waves
- Middle ear: transmits eardrum's vibrations through a piston made of the hammer, anvil, and stirrup
- Cochlea: sound waves trigger nerve impulses
- Inner ear: contains cochlea, semicircular canals and vestibular sacs
What is the signal detection theory?
predicts how/when we detect the presence of a faint stimulus amid background stimulation
Compare and contrast conduction hearing loss and sensorineural hearing loss:
- Conduction hearing loss is caused by damage to the mechanical system that conducts sound waves to the cochlea;
- Sensorineural hearing loss is nerve deafness caused by damage to the cochlea's receptor cells
What are the 4 skin senses?
Pressure, warmth, cold, and pain
the spinal cord contains neurological gates that blocks pain signals/allows them to pass to the brain
What are the 5 tongue tastes?
Sweet, sour, salty, bitter, umami (monosodium glutamate)
Idea that one sense may influence another sense (smell, taste, and texture)
What is the sense of olfaction?
the sense of smell
What is kinesthesis?
The sense of our body parts' position and movement
the sense of body movement/position (including sense of balance)
What is Gestalt?
an organized whole; Gestalt psychologists emphasize our tendency to integrate pieces of info into meaningful wholes
What are some optical illusions/perceptual tendencies?
- Figure-ground: organization of visual field into objects that stand out from their surroundings
- Depth perception: ability to see objects in 3D
- Binocular cues: Depth cues (retinal disparity and convergence) that depend on use of 2 eyes
- Retinal disparity: brain computes distance; the greater the difference between 2 images, the closer the object
- Convergence: the extent to which the eyes verge inward when looking at an object (greater the inward strain, the closer the object)
- Context effects change our perceptions
- Lightness constancy: we percieve an object having constant lightness even when illumination varies
- Phi Phenomenon: illusion of movement created when 2+ adjacent lights blink on/off
- Perceptual adaptation: the ability to adjust to an inverted visual field
- Perceptual constancy: percieving objects as unchanging even as illumination/retinal images change
a mental predisposition to percieve one thing and not the other