Psychology Exam 2

Sensation

Detecting physical energy with our sense organs (eyes, ears, skin, nose, tongue)

Perception

The brain’s interpretation of the raw sensory information

Illusion

The way we perceive a stimulus doesn’t match its physical reality

Transduction

Conversion of an external stimulus into a neural signal

Sensory Receptors

Specialized cells designed to convert a certain kind of external information into a neural signal

Sensory Adaptation

Sensory neurons adjust their sensitivity based on recent stimulus history.

Aftereffects

opposing sensory or perceptual distortions that occur after adaptation.

Psychophysics

the study of how our sensations (psychological events) correspond to physical events in the world.

Absolute threshold

The lowest level of a stimulus needed for the nervous system to detect a change 50% of the time.

Just Noticeable Differences (JND)

The smallest change in the intensity of a stimulus that we can detect

Signal Detection Theory

How stimuli are detected under different conditions

Signal

What you are trying to detect

Noise

Similar stimuli that might compete with the signal and interfere with your ability to detect the signal

Dichotic listening

Play different information through each ear of headphones. Information reported only from the attended ear.

Cocktail party effect

Happens when important information pops out in a conversation that you are not attending

Bottom-up processing

Constructing a representation from parts & basic features (ex. Trying to see anything in a dotted photo the first time viewing)

Top-down processing

Processing influenced by previous experience & knowledge (ex. Seeing a dog in the dotted photo after someone told you there is one in the photo)

Perceptual sets

Set formed when our expectations influence our perceptions

Sclera

The white part of the eye

Pupil

Circular hole where light enters (the black center of eye)

Iris

Colored portion of the eye that controls pupil size letting in more or less light (the colored part surrounding the pupil)

Cornea

Curved, transparent layer covering the iris & pupil that helps focus light

Lens

Oval shaped disc that bends light

Retina

Membrane at the back of the eye responsible for converting light into a neural signal

Fovea

Central portion of the retina, responsible for visual acuity

Acuity

Sharpness of vision

Myopia

Nearsightedness (eye is too long)

Hyperopia

Farsightedness (eye is too short)

Rods

Respond under low levels of light. Not color sensitive. More common outside of fovea

Cones

Sensitive to fine detail. Primarily located in fovea. Color Sensitive. Less plentiful than rods

Optic Nerve

A bundle of axons that travels from the retina to the brain

Blind Spot

Area of the retina where the optic nerve exits the eye

Hue

The color of light

Opponent Process Theory

We perceive colors in terms of three pairs of opponent colors

Color Blindness

Inability to see some or all colors

Depth perception

Ability to judge distance and spatial relations

Binocular depth cues

Involves two eyes

Binocular disparity

Each eye sees slightly different images; brain can judge depth

Convergence

Eyes converge to see near objects

Monocular depth cues

Involve one eye

Relative size

Distant objects look smaller than closer objects (Part of monocular depth cues)

Texture gradient

Texture is clearer on closer objects (Part of monocular depth cues)

Interposition

Closer objects appear in front of distant objects (Part of monocular depth cues)

Linear perspective

Parallel lines converge with distance (Part of monocular depth cues)

Height in plane

Distant objects appear higher than closer objects (Part of monocular depth cues)

Light and shadow

Shadows can tell us about form (Part of monocular depth cues)

Motion parallax

Closer objects pass more quickly than distant objects (Part of monocular depth cues)

Size constancy

Perceive stimuli as consistent across varied conditions

Color constancy

perceive stimuli as consistent across varied conditions

Perceptual constancy

perceive stimuli as consistent across varied conditions

Shape constancy

perceived shape is constant, even through shape of he image (on retina) varies

Gestalt Principles

rules that govern how we perceive objects as wholes within their overall context (proximity, similarity, continuity, closure, symmetry, figure-ground)

Common fate

objects moving at the same direction and at the same speed are perceived as a group. (ex. Geese flying in a “V”)

Synchrony

stimuli that are perceived to occur at the same time are perceived as part 

of the same event. (ex. Drop keys and a sound occurs the instant it hits the floor)

Habituation

Process of responding less strongly over time to repeated stimuli; getting used to a stimulus; usually a neutral stimulus.

Sensitization

Process of responding more strongly over time to repeated stimuli; usually a dangerous or irritating stimulus.

Classical Conditioning

Ivan Pavlov

physiologist, first to demonstrate classical conditioning, best known for their work on dog digestion

Neutral stimulus

Initially evokes no specific response

Unconditioned stimulus (UCS)

Produces a reflexive / automatic response

Unconditioned response (UCR)

The automatic response (already there, not learned)

Conditioned stimulus (CS)

Initially neutral, becomes associated with UCS

conditioned response (CR)

Automatic response now triggered by CS

Acquisition

Learning phase; when UCS is paired with CS. After which CS produces (aquires) CR

Extinction

CS appears alone and the CR weakens. CR is eventually eliminated (becomes extinct)

Spontaneous Recovery

Extinct CS suddenly emerges again after a delay. Relearning happens more rapidly than initial learning

Renewal effect

Sometimes a response is extinguished when the organism is in different context(s); however, the response may come back when the organism returns to the original setting.

Generalization

Respond to stimuli that are similar to the conditioned stimulus (ex. Dog salivating to other bell tones)

Discrimination

Respond to a particular stimulus but not similar stimuli. Prevents overgeneralization. (ex. Dog salivating to a bell but not to a gong which is similar)

Blocking

A prior association with a conditioned stimulus prevents learning of an association with another stimulus.

Preparedness

Biological predisposition to learn some associations more quickly than other associations.(ex. Phobia of dark, heights, spiders)

Taste aversion conditioning

Associating nausea with food. Helps avoid food that is poisonous or gone bad. Is an example of preparedness.

Fear conditioning

Negative associations can be so powerful that they are learned extremely rapidly. Easily generalized to other similar stimuli.

Chronic Drug Use

When a drug is used, it is associated with the cues present at the same time. These cues help predict that “the drug is coming.” (ex. A room, odor)

Operant Conditioning

Behaviors as a result of the consequences

Discriminative Stimulus

Any stimulus that signals the presence of reinforemmmmment

Reinforcement

Increased likelihood of a behavior being repeated

Punishment

Decreased likelihood of a behavior being repeated

Positive Reinforcement

Increase behavior by adding something good

Negative reinforcement

Increase behavior by subtracting something bad

Positive punishment

Decrease behavior by adding something bad

Negative punishment

Decrease behavior by subtracting something good

Continuous

behavior is rewarded every time it is performed. (faster acquisition, faster extinction)

Partial

Behavior is only rewarded some of the time (slower acquisition, slower extinction)

Fixed Ratio

reinforce after constant # of responses. (Ex. A salesperson receiving a bonus for every five items sold.)

Variable Ratio

Reinforce after a variable # of responses. (Ex. Putting money into a slot machine.)

Fixed Interval

Reinforce after constant amount of time. (Ex. Teacher giving weekly quizzes.)

Variable Interval

Reinforce after a variable amount of time. (Ex. Teacher giving pop quizzes at variable intervals.)

Social Learning Theory

Learning is a cognitive process derived from social observation, and does not necessarily require reinforcement.

According to Bandura, observational learning consists of 4 parts:

1. Attention – you must pay attention to learn!

2. Retention – you must be able to keep the behavior in

your memory.

3. Initiation – you must be able to execute (or initiate)

the learned behavior.

4. Motivation – you must possess motivation to engage

in observational learning.

Insight Learning

Grasping the underlying nature of a problem (“aha” moment)

Encoding

Getting information into memory

Storage

Keeping information in memory

Retrieval

Accessing information from memory

Automatic Processing

Encoding of details like time, space, frequency, and the meaning of words.

Effortful Processing

Encoding of details that require effort and attention on your part.

Levels of processing

The multiple levels at which encoding can occur, ranging from shallow to deep.

Self-Referential Encoding

Encoding based on an event’s relation to our self=concept. (leads to enhanced memory for the event)

For a memory to go into storage, it must pass through three stages:

◦ Sensory Memory

◦ Short-Term Memory

◦ Long-Term Memory

Recall

Generating remembered information.