Ap Psych Unit 3: Sensation and Perception

Sensation

Detecting stimuli and encoding neural signals. (Feeling/sensing something).

Transduction

Stimuli/energy must be converted into natural messages so the brain can understand it.

Perception

Organizing/processing sensations and thinking about/understanding it.

Bottom-Up Processing

Sensory info to the brain to begin processing.

Top-Down Processing

Preconcieved notions in the brain begin prosessing.

• Flinching

• Stereotypes

Selective Attenion

At any one time we focus consious awareness on select stimuli, generally at the expense of other stimuli.

• We still detect other stimuli

• Driving

• Studying

Threshold

The point where we know it’s a stimuli.

Absolute Threshold

Minimum amount of stimuli needed for detection about 50% of the time.

Signal Detection Theory

Detection depends on the individual as well as the stimulus.

Subliminal Messaging

More towards the unconscious. Subliminal means below threshold.

Difference/Just Noticeable/Differential Threshold

When you’re able to notice a difference.

Webber’s Law

There’s gonna be a proportion. The difference in a ratio.

Sensory Adaptation

We will stop noticing something that’s constant.

Sensory Restriction Meaning #1

When one sense is gone, others will improve.

Sensory Restriction Meaning #2

The mind is set free when the senses are removed.

Light Energy

Light/color are pulses of electromagnetic energy/waves.

Wave Length

Determines the hue-color experienced.

Amplitude

Height of wave.

• high amplitude=more energy=brighter colors

Cornea

Outer covering, protection for the eyeball.

Pupil

Opening (black part) of eyeball. Lets light in.

Iris

Colored muscle, pretty part, blocks light.

Lens

Focuses light rays into the retina.

Accomidation

Curvature changes to focus better.

Visual Acuity

Sharpness of vision.

Nearsighted

Light from far away objects hits in front of retina.

• See close objects clearly

• Eyeball may be too long

Farsighted

Light from nearby objects focused behind retina.

• See far away objects clearly

• Eyeball may be too short

Retina

Lines the back of the eyeball, flips stuff like a mirror, is a reciever.

Receptor Cells

Rods and cones.

Rods

Outline of object, black and white, shading, peripheral vision.

Cones

Color, details, requires plenty of light.

Bipolar Cells

Organize what you see.

Ganglion Cells

Transfer what you see.

Optic Nerve

Axons of ganglion cells.

Blindspot

Where the optic nerve leaves the eye, the opening. Your brain fills it in for you.

Fovea

Area of central focus.

Feature Detectors

Turns everything the eyeball is taking in into an image.

Parallel Processing

Our brain can do multiple things at once.

Color Vision

Colors get reflected. You absorb every color EXCEPT the one you’re seeing.

Young-Helmholtz Trichromatic Theory

Retina has 3 types of color receptors that combine.

• Red, green, and blue

Opponent Process Theory

Thalamus cells responsible for seeing one of 2 colors.

• Black or white

• Green or red

• Blue or yellow

• You can only see one at a time

After Images

See the “opponent” color after looking at a color long enough.

Soundwaves

Molecules of air bumping into eachother.

Amplitude

Loudness.

Decibels

Measure of sound energy.

Frequency/Wavelength

Pitch.

• Long waves=low frequency/pitch

  • Short waves=high frequency/pitch

Outer Ear

What you can see on the outside.

Auditory Canal

Passageway into the ear.

Eardrum/Tympanic Membrane

Membrane that vibrates to transmit sounds from outer to middle ear.

Middle Ear

Transmits sound from eardrum to inner ear.

Piston/Ossicles

3 delicate bones.

• Hammer, anvil, and stirrup

• They vibrate each other

• I HAS a piston

Inner Ear

Cochlea, oval window, basilar membrane, hair cells, and auditory nerve.

Cochlea

Snail shaped tube filled with fluid that vibrates.

Oval Window

Cochlea’s membrane attached to the stirrup.

Basilar Membrane

Runs through middle of cochlea.

Hair Cells

Line basilar membrane and bend to transfer sound.

Auditory Nerve

Carries info from cochlea into the brain.

Place Theory

WHERE it vibrates determines the pitch.

• Like a piano

• Works for medium to high pitches

Frequency Theory

Basilar membrane determines the pitch.

• Like a guitar

• Works for low to medium pitches

Volley Principle

Cells alternate with place AND speed to determine the pitch.

Locating Sound

Hits one ear first.

Sound Shadow

Sound bounces off walls first.

Just Noticeable Difference (JND)

0.000027 seconds.

Conduction Deafness

Cannot gets sounds into cochlea.

• Hearing aids help

Sensorineural/Nerve Deafness

Damage to cochlea/hair cells.

• Caused by age, and exposure to loud sounds

• Hearing aids barely help

• Hair cells won’t bend

Pressure, warmth, cold, and pain.

4 skin senses

Pain

The bodies way of telling you something’s wrong

Phantom Limb Sensations

7 in 10 amputees feel pain in their missing limb.

Gate-Control Theory

The spinal cord contains a gate to allow/block pain signals.

Small Fibers

Open the gate and transmit pain.

Large Fibers

Close the gate, transmit other sensations, and block pain.

Sweet, sour, bitter, salty, and umami

5 tastes

Tastebuds

• 200

• Pores

• They reproduce

Age, alcohol, and tobacco

Causes of taste bud reduction

Flavor

Combination of taste and smell.

Olfaction

Experiencing smell.

Smell

• Least sensitive

• Chemical sense

• Declines with age

• Tied with memory

Kinesthesis

Body position and movement (knowing where your body is).

Vestibular Sense/Equilibrium

Position and balance of body.

Semicircular Canal

Filled with fluid to act like a level for balance.

Fluid in the semicircular canal is shaken up.

What causes dizziness?

Illusions

Show how you organize and interpret sensations.

Visual Capture

Vision tends to dominate the other senses.

Gestalt

Seeing things as a whole.

Figure and Ground

The brain creates a distinction between an object and its background.

Gestalt Rules of Grouping

People/brains like to organize figures.

Proximity

Desks in rows.

Similarity

Same jerseys.

Continuity

Concessions.

Closure

Dashed lines on the road.

Connectedness

GES and GHS.

Depth Perception

Transforms 2D images into 3D knowledge.

Binocular Cues

BOTH eyes helping us determine depth.

Retinal Disparity

Different images on each retina create depth in the brain.

Convergence

How much our eyes turn inward alerts the brain to depth.

Monocular Cues

Some depth is done with just one eye.

Relative Size

2 similar objects, one having a larger image on the retina means it’s closer.

Interposition

A blocked view means the thing blocking is closer.

Relative Clarity

The more clear something is, the closer it is.

Texture Gradient

The more distinct an image is, the closer we perceive it as.

Relative Height

Higher up objects are perceived as farther away.