AP unit 3: sensation and perception

Bottom-up processing

When the environment influences our thinking (sensation)

Volley principle

When they fire in rapid succession, neural cells can reach a combined frequency of around 1000 waves per second

Perceptual set

mental predispositions of what we expect to see influences what we really see

Absolute threshold

minimum amount of stimulation needed to detect senses 50% of the time

Lens

shapeshifting clear structure behind pupil to help focus images

Salty

sodium needed for physiological processes

Subliminal perception

stimuli that is below your absolute threshold and we can't detect 50% of the time.

Organ of Corti

strucutre in Cochlea that produces neural impulses in response to sound waves

Psychophysics

studies the relationships between physical characteristics of a stimulus

Proximity

tendency to group nearby figures together

Continuity

tendency to see continuous patterns instead of discontinuous ones

Perception

the brain recognizes and interprets sensory input; allows us to recognize meaningful objects & events

Different threshold

Minimum difference between 2 stimuli that a person can detect 50% of the time.

Blind spot

-a result of the optic nerve leaving the eye -no receptor cells anymore

Cochlea

-bony tube filled with fluid in the inner ear - vibrations of sound cause its membrane to vibrate and shakes the fluid -shaking of the fluid causes ripples in basilar membrane & bends hair cells that line the surface

Smell (olfaction)

-chemical sense in which odorants enter the nasal cavity and stimulates 5 million receptors to sense smell. - brain region for smell is connected to the one for memory; strong memories= strong scents

Inner ear

-consists of cochlea, semicircular canals, vestibular sacs

Sensory adaptation

-diminished sensitivity caused by constant stimulation -helps u get less distracted by background information

Relative size

-monocular cue -Tendency to perceive that the object hat looks smaller is farther away

opponent process theory of color vision

-opposing retinal processes allow us to see color - color processes: red vs. green perception and blue vs. yellow perception

How experience and culture affect perception

-past learning shapes perception -norms & stereotypes of a group of people affect perception

Helmholtz's place theory

-theory that connects the pitch we hear to what area of the cochlea membrane is stimulated -Believes different sounds are caused waves triggering activity at different places along the cochlea's basilar membrane - explains our ability to hear high-pitched but not low-pitched sounds

Frequency/temporal theory

-theory that the brain recognizes the pitch by looking at the frequency of neural impulses -sound waves cause basilar membrane to vibrate, triggering neural impulses at the same rate.

Steps of Stimulus Processing

1.Light waves 2. Cornea 3. Pupil 4. Lens 5. Retina (rods/cones: transduction + trichromatic theory) 6. Bipolar cells; ganglion cells 7. Opponent process theory of color vision 8. Feature detectors: Parallel processing 9. Perception

Weber's Law

2 stimuli need to differ by constant min percentage instead of amount

Cognitive style

A way of processing stimuli in environment that affects how we look at the world -Field-dependent and independent approach

Selective Attention

-When our attention is somewhere else, we can't notice part of our environment

Gestalt Psychology

-Emphasized that our conscious perception is whole -We first try to find the object that is different from its surroundings -Organize stimuli by grouping

Inattentional blindness

-Inability to see something in our direct view because our attention is elsewhere

Interposition

-Monocular cue - We see the object as closer if it partially blocks our view of another object

Figure-ground

-Organizing our visual field by looking for objects that stand out from surroundings

Perceptual constancy

-See objects as the same even when the angle, distance, and light is different

Umami

(savory and MSG) Proteins that grow and repair tissue

Fovea

- Area in the retina that is the center of the visual field - very concentrated w/ cones

Kinesthesis (Proprioception sense)

- How we sense the movement and position of ourselves and body parts -senses strength of effort exherted -Without it we would have to watch our limbs in order to coordinate movement

Taste

- Our tongue has receptors for different types of tastes and they have survival functions - Sweet, Sour, Umami, Salty, Bitter

Rods

- Receptors in the retina that recognizes black, white and gray color - Responsible for peripheral vision and seeing in the dark when cones are not responsive

Cones in retina

- Receptors in the retina that works in daylight and well-lit conditions - concentrated amt. in fovea -processed by opponent-process cells

Cochlear implant

- a device tha converts sound into electrical signals -Stimulates auditory nerve by the electrodes inside the cochlea -helps children improve in oral communication -only helps adults regain hearing if their brain learned how to process sound when they were a child

Parallel processing

- a way of processing functions -Brain divides visual picture into smaller aspects and works on them simultaneously

Feature detectors

- brain nerve cells that respond to the particular features of a stimulus (ex:shape) -Recieves information from ganglion cells in retina

Middle ear

- chamber in between the eardrum and cochlea -contains hammer, anvil, stirrup -Picks up vibrations and transmits them to the cochlea

Change blindness

- inability to detect minor changes in visual field

retina

- light-sensitive inner surface of eye - has receptor rods/cones and layers of neurons -beginning of visual formation processing -converts light energy into neural impulses (Transduction)

Vestibular sense

- our ability to feel the position of our head and body - vestibular sacs & semicircular canals have receptors that send messages about head's position to the cerebrellum -Helps us balance and stay upright

Signal Detection theory

- predicts how & when we detect the presence of a small signal - detection partly depends on experience, expectations, motivation, alertness - why we respond to same stimulus differently and when environment changes

Retinal disparity

- the difference between the 2 images our eyes see - greater the difference, the closer the object

Depth-perception

-Ability to see objects in 3D when the images our retina sees are 2D -Lets us guess how far an object is from us

Pupil

Adjustable opening in the center of the eye that light enters through

Visual cliff

An experiment used to test for depth perception; apparent drop from the floor but not an actual one

Papillae

Bumps on tongue that are covered by taste buds

functional fixedness

Cognitive bias which a person only uses an object in the way it is normally used

Prosopagnosia

Cognitive disorder that you are unable to recognize your own face and others'

Iris

Colored muscle that surrounds the pupil and controls its size -Dilates/constricts pupil based on light intensity

Monocular cues

Depth cues for each eye separately

Binocular cues

Depth cues that need the use of 2 eyes

Wavelength

Distance from a wave peak to the next -determines the color we see, our sensory experience, intensity

Sensorineural hearing loss

Hearing loss as a result of damaged cochlea receptor cells or auditory nerves - biological factors: heredity/age

Amplitude

Height of a wave that determines the intensity

Relative clarity

Less blurry objects are closer than cloudier objects

Motion perception/parallax

Our brain presumes shrinking objects as retreating and objects that are getting bigger as coming closer.

top-down processing

Our thinking determines what our senses detect (perception)

Linear Perspective

Parallel lines seem to meet in the distance (monocular cue)

Relative height

Perceive objects higher in the field of vision are farther away

Field-dependent approach

Perceive the world as a whole with not a lot of detail (Levelers)

Field-independent approach

Percieve aspects of environment as separate from each other with a lot of detail (sharpeners)

Observer characteristics of perception

Personality: Our unique way of thinking and behaviors Motivation: desires and needs to shape perceptions Values: we deem as important to shape perception

Closure

Tendency to fill in gaps to create a complete picture

Shape constancy

Tendency to see the shape of a familiar object as the same even when different shapes are sent to the retina

Accommodation

The lens focuses the rays by changing its own thickness

Gate Control theory

The theory that spinal chord consists of neurological gates that can push away pain or allow it to be sensed

Brightness constancy

Think that the object has same brightness even when light changes

Color constancy

Thinking a familiar object has the same color even when the light changes reflected wavelengths

Vision capture

Vision competes with other sense and normally wins

Perceptual adaptation

We are able to adjust to a distorted visual field

Priming

We create associations that create predipositions that affect our senses

size constancy

We detect objects to have the same size no matter its distance from us

Mcgurk Effect

When one sound component is used with a visual component of a different sound, there is a sense of a third sound

Relative motion

When we're moving, stable objects look like they're moving too

Trichromatic theory of color

Young and Helmhotz - retina contains 3 color receptors: red, blue, green -Combinations of these 3 receptors can make any color

Outer ear

channels sound waves through auditory cannal and the eardrum, causing a mechanical chain reaction

Synethesia

condition in which when one sense is activated, another unrelated one is activated too.

Transduction

converting one form of energy into another that our brain can use

Conduction hearing loss

hearing loss as a result of damaging our mechanical system that directs sound waves to cochlea

Phi phenomenon

illusion of a movement as a result of 2/more nearby lights blinking on and off in quick patterns

Context effect

interpreting what we see by the context of it

Optic nerve

nerve that takes neural impulses from the eye to the brain

Sweet

our energy source

Bitter

possible poisons

sour

potentially toxic acid

Tactile touch

pressure, cold, warmth, pain

Sensation

process of detecting environmental stimuli and converting them into signals that can be detected by the nervous system

Sensory restrictions

there is a critical period for normal sensory & perceptual development