Intro to Psychology - Exam Two

Sensation

Sense organs gather information, energy is converted to neural signals via transduction

Transduction

The conversion of physical energy into neural signals that the brain can understand.

Perception

Brain interprets neural signals, leads to a psychological experience.

Detection Question of Sensation

This question is concerned with the limits on our ability to detect very faint signals. The absolute threshold notifies the minimum energy detected 50% of the time.

Difference Question of Sensation

This question is concerned with limits on our detection abilities, but in this case with our ability to detect very small changes between stimuli. The difference threshold is the minimum change detected just 50% of the time.

Weber’s Law

Threshold is a constant fraction of the original stimulus.

Scaling Question of Sensation

How we perceive the magnitudes (intensities) of clearly detectable stimuli. Stevens’s Power Law is a law that states that perceived intensity is equal to physical intensity, but raised/lowered to some constant power.

Sensory Adaptation

Sensitivity to unchanging stimuli disappears over time. Exceptions are things like vision (saccades), very loud noises, and bodily pain.

Waveforms

Amplitude - intensity, height of a wave at its crest, Wavelength - distance in one cycle of a wave, Frequency - the number of times the waveform cycles in 1 second

Structure of the eye

1. Cornea bends light waves to be focused on retina, passes thru pupil & cornea

2. The iris creates color in the eye and determines how much light enters

3. Light waves travel to retina, transduction occurs

Structure of the retina

Composed of ganglion, bipolar, and receptor cells.

1. Light waves absorbed by photopigments within receptor cells creating neural impulses that describe visual image.

2. Neural info. conveyed to bipolar cells which send it to ganglion cells.

3. Optic nerve = ganglion cells bundled together, exits the eye carrying information to brain

Properties of Rods

120 million in each eye, located mainly in periphery of retina, primarily responsible for dim light vision, responsible for achromatic (colorless) vision, lead to low visual acuity

Properties of Cones

6 million in each eye, located mainly in fovea and central retina, primarily responsible for bright light vision, responsible for chromatic (color) vision, lead to high visual acuity b/c each communicates w/one bipolar cell

Trichromatic Theory of Color Vision

There are three types of cones, short wavelengths are blueish, medium wavelengths are greenish, and long wavelengths are reddish. Perceived color results from additive mixture. Explains colorblindness.

Opponent Process Theory of Color Vision

There are three opponent-process cell systems helping us to see color and that they are located at the post-receptor level of processing. There’s red-green, blue-yellow, and black-white. It explains afterimages.

Composite Theory

Color information is processed by the cones according to trichromatic theory, but color information is processed at the post-receptor cell level according to opponent-process theory.

How the ear works

The ear is divided into the outer, middle, and inner ear.

1. The pinna collects sounds and funnels them through auditory canal to the eardrum.

2. Sound waves produce vibrations in the eardrum, and moves the malleus, incus, and stapes and the three tiny bones in the ear.

3. Movement of stapes creates vibrations of oval window, a membrane covering an opening in the inner ear.

How we distinguish pitch

Place theory can explain how we hear the entire range of pitches except for low pitches, and frequency theory can explain how we hear these low pitches.

• The brain uses the firing rate to differentiate the low frequencies and the location of maximal hair cell activity along the basilar membrane to distinguish the high frequencies.

Bottom-Up, Top-Down Processing & Humans

The processing of incoming sensory input as it travels up from the sensory structures to the brain.

• Bringing the sensory input from the environment to the brain to be interpreted

The brain’s use of knowledge, beliefs, and expectations to interpret the sensory information.

• Processing of information coming from the top (the brain) back down to the lower sensory structures

Humans utilize both top-down and bottom up sensations, although there are more top-down than bottom-up, at about a 10:1 ratio.

Understand how various illusions demonstrate that perception is an active process influenced by the situational context (contextual effect)

An effect on perception occurs when we use the present context of sensory input to determine its meaning.

Understand how various illusions demonstrate that perception is an active process influenced by the past experience (perceptual set), expectation, belief, and culture

Perceptual set: When we interpret an ambiguous stimulus in terms of how our past experiences have “set” us to perceive it. Don’t we usually see sports games in favor of “our” team? We are set by past experiences to see them in this biased way. This means that past experiences guide our perception with top-down processing.

Understand how various illusions demonstrate that perception is an active process influenced by past experiences, expectation, belief, and culture

Perceptual bias and contextual perceptual effects are good examples of how our beliefs, and expectations guide our interpretation of the world.

Figure-and-Ground Principle

Gestalt psychologists developed a basic rule for perceptual organization; the brain organizes sensory information into a figure or figures (the center of attention) and ground (the less distinct background).

Closure and Subjective Contours

The brain completes incomplete figures to form meaningful objects.
A line or shape that is perceived to be present but does not really exist. The brain creates it during perception.

Perceptual Constancy

The perceptual stability of the size, shape, brightness, and color for familiar objects seen at varying distances, at different angles, and under different lighting conditions.

Retinal Disparity

Refers to the fact that as the difference between the two retinal images increases, the distance from us decreases.

Linear Perspective

As parallel lines recede away from us, they appear to converge — the greater the distance, the more they converge.

Interposition

A monocular depth cue referring to the fact that if one object partially blocks our view of another, we perceive it as closer to us.

Classical Conditioning: Definition

Acquiring a new response (the conditioned response) to a previously neutral stimulus (the conditioned stimulus) that reliably signals the arrival of an unconditioned stimulus.

Classical Conditioning: Little Albert Study

Watson and Rayner studied an infant between 9-13 months, Little Albert. They repeatedly paired a white rat with a loud noise. The rat alone eventually produced a fear response in Albert. They afterward tested other stimuli such as a rabbit and Santa Claus mask to see what would make him cry.

Classical Conditioning: Unconditioned Stimulus

The stimulus in a reflex that automatically elicits an unconditioned response.

Classical Conditioning: Unconditioned Response

The response in a reflex that is automatically elicited by the unconditioned stimulus.

Classical Conditioning: Neutral Stimulus

A stimulus that does not naturally elicit the to-be-conditioned response.

Classical Conditioning: Conditioned Stimulus

The stimulus that comes to elicit a new response (the conditioned response) in classical conditioning.

Classical Conditioning: Conditioned Response

The response that is elicited by the conditioned stimulus.

Classical Conditioning: Acquisition

Acquiring a new response (the conditioned response) to the conditioned stimulus.

Classical Conditioning: Extinction

The diminishing of the conditioned response when the unconditioned stimulus no longer follows the conditioned stimulus.

Classical Conditioning: Spontaneous Recovery

A partial recovery in strength of the conditioned response following a break during extinction training.

Classical Conditioning: Stimulus Generalization

Stimuli similar to the CS elicit the CR. The more similar the stimulus is to the CS, the stronger the response will be. (ex: Little Albert & rabbits)

Classical Conditioning: Stimulus Discrimination

The elicitation of the conditioned response only by the conditioned stimulus or only by a small set of highly similar stimuli that includes the conditioned stimulus.

Classical Conditioning and Conditioned Taste Aversion

Classically associated with food poisoning and illness. Classical conditioning supercharged. When a UCS (Illness/Bacteria) happens at the same time as an NS (Food) → the UCR (Nausea) occurs, and makes you avoid that food thereafter.

Operant Conditioning: Definition

Learning to associate behaviors with their consequences. Behaviors that are reinforced (lead to satisfying consequences) will be strengthened, and behaviors that are punished (lead to unsatisfying consequences) will be weakened.

Edward Thorndike’s Law of Effect

Says that any behavior that results in satisfying consequences tends to be repeated and that any behavior that results in unsatisfying consequences tends not to be repeated.

Operant Conditioning: Positive vs Negative Reinforcement

Reinforcement in which an appetitive (pleasant) stimulus is presented.
Reinforcement in which an aversive (unpleasant) stimulus is removed.

Operant Conditioning: Positive vs. Negative Punishment

Punishment in which an aversive (unpleasant) stimulus is presented.
Punishment in which an appetitive (pleasant) stimulus is removed.

Operant Conditioning: Primary vs Secondary Reinforcers

A stimulus that is innately reinforcing. Food and water are good examples.
A stimulus that gains its reinforcing property through learning. Examples of secondary reinforcers are money, good grades, and applause.

Operant Conditioning: Continuous Schedule of Reinforcement

Reinforcing the desired operant response each time it is made. But we aren’t reinforced for every response in everyday life.

Operant Conditioning: Partial Schedules of Reinforcement

Reinforcing the desired operant response only part of the time.

Operant Conditioning: Fixed-Ratio Schedule

A partial schedule of reinforcement in which a reinforcer is delivered each time a fixed number of responses is made. The fixed number can be any number greater than one. For example, a rat might have to press the lever 10 times before the delivery of a reinforcer (usually food).

Operant Conditioning: Variable-Ratio Schedule

A partial schedule of reinforcement in which the number of responses it takes to obtain a reinforcer varies on each trial but averages to a set number across trials. For example, a rat might have to press a lever 10 times to get a reinforcer, then 21 times, then 6 times, and so on.

Operant Conditioning: Fixed-Interval Schedule

A partial schedule of reinforcement in which a reinforcer is delivered after the first response is given once a set interval of time has elapsed. For the rat example, a food pellet would be delivered following the first lever press after one minute had elapsed.

Operant Conditioning: Variable-Interval Schedule

A partial schedule of reinforcement in which the time that must elapse on each trial before a response will lead to the delivery of a reinforcer varies from trial to trial but averages to a set time across trials. Think about how students’ study behavior would have to change to do well on the exams with this new schedule. Students would have to study more regularly because a test could be given at any time.

Partial schedules in terms of rates of responding and extinction

Continuous - slow response/quick extinction
Fixed-Ratio - fast response/medium extinction
Fixed-Interval - medium response/medium extinction
Variable-Ratio - fast response/slow extinction
Variable-Interval - fast response/slow extinction

Operant Conditioning: Acquisition

The strengthening of a reinforced operant response.

Operant Conditioning: Extinction

The diminishing of the operant response when it is no longer reinforced.

Operant Conditioning: Spontaneous Recovery

The temporary recovery of the operant response following a break during extinction training.

Operant Conditioning: Stimulus Generalization

Giving the operant response in the presence of stimuli similar to the discriminative stimulus. The more similar the stimulus is to the discriminative stimulus, the higher the operant response rate.

Operant Conditioning: Stimulus Discrimination

Learning to give the operant response only in the presence of the discriminative stimulus.

Operant Conditioning: Shaping

Training a human or animal to make an operant response by reinforcing successive approximations of the desired response.
Ex:
The researcher would watch the behavior of the pigeon and would begin the shaping by reinforcing the pigeon for going in the general area of the key. This would get the pigeon near the key. The researcher would then reinforce the pigeon any time its head was in the area of the key. The pigeon would keep its head near the key and would probably occasionally touch the key. Then the researcher would reinforce the pigeon for touching the key.

Drive-Reduction Theory of Motivation

Proposes that our behavior is motivated to reduce drives (bodily tension states) created by unsatisfied bodily needs to return the body to a balanced internal state.

Incentive Theory of Motivation

Proposes that our behavior is motivated by incentives, external stimuli that we have learned to associate with reinforcement.

Arousal Theory of Motivation

Proposes that our behavior is motivated to maintain an optimal level of physiological arousal.

Yerkes-Dodson Law

Describing the relationship between the amount of arousal and the performance quality on a task—increasing arousal up to some optimal level increases performance quality on a task, but increasing arousal past this point is detrimental to performance.

Effects of reinforcement on creativity and problem-solving

Reinforcement is best for behaviors with no intrinsic motivation. If a behavior has intrinsic motivation and you are also given reinforcement, the quality of your creativity and problem-solving decreases.

Extrinsic and Intrinsic Motivation

One is “the desire to perform a behavior for external reinforcement.” The other is “the desire to perform a behavior for its own sake.”

Overjustification Effect

A decrease in an intrinsically motivated behavior after the behavior is extrinsically reinforced and then the reinforcement is discontinued.

Self-Determination Theory

Humans have three basic psychological needs: Autonomy, Competence, and Relatedness. Satisfaction of basic psychological needs predicts intrinsic motivation and promotes well-being.

Latent Learning

Learning that occurs but is not demonstrated until there is incentive to do so. Think about studying for an exam in one of your courses. What you have learned is not openly demonstrated until you are tested on it by the exam. You learn, but you do not demonstrate the learning until reinforcement for demonstrating it is available.

Observational Learning/Modeling

Learning by observing others and imitating their behavior. For example, it helps us learn how to play sports, write the letters of the alphabet, and drive a car.

Bobo Doll Studies

In one experiment, some of the children in the study were exposed to an adult who beat, kicked, and yelled at the Bobo doll. After observing this behavior, each child was taken to a room filled with many appealing toys, but the experimenter upset the child by saying that these toys were being saved for other children. The child was then taken to a room that contained a few other toys, including the Bobo doll. Can you guess what happened? The child started beating on the Bobo doll just as the adult model had done.

Effects of violent video games

Short-term effects from lab findings

Observational learning in non-human animals

Octopus - trained to touch red or white ball & gets reward eventually. A second one just observes, not plays. When the scientist puts the second one in that situation, 90% of the time the octopus will touch the colored ball.
Crows - remember who banded them and engage in aggressive behavior towards human w/mask on. Other crows observing banding know that person wasn’t good news, and even others who didn’t see it knew somehow.