Intro Psych Exam 3 @ JHU Fall 2025 (Firestone)

Personality

A person's characteristic way of thinking, behaving, feeling, and interacting with others.

Personality Traits are... (generality)

more general than an individual level, more specific than a human level

Reliability

The quality of a personality test that produces the same score for the same person over multiple retests. Measured by test-restest; higher = more reliable. (ex. size of someone's forehead)

Validity

The quality of a personality test that accurately measures the characteristic of interest. (ex. mouth openness and awe)

Qualities of a good personality test

Reliability and validity

Trait vs. state

State is not stable, trait is stable. Ex. state anxiety = how anxious you are in the moment, trait anxiety = your anxiety in general

MBTI Test

A very popular test despite no evidence of reliability. Weakly predicts good managers, teammates, etc.

x% of test-takers get a different MBTI type upon retake.

50

The Big Five

A reliable and valid personality test. Measures Openness, Conscientiousness, Extraversion, Agreeableness, and Neuroticism (emotional stability). These traits are value-neutral and independent.

True or false: People's perceptions of themselves with respect to the Big Five traits often match others' perceptions of these traits.

True

Why are people's personalities different?

Nature and nurture

Twin studies

Compare differences between monozygotic and dizygotic twins to study the effect of genetics. If the difference between identical twins is less than the difference between fraternal twins, then genetics is a likely factor.

Monozygotic twins

Identical twins (same genes)

Dizygotic twins

Fraternal twins (genetic siblings)

Heritability

The proportion of a trait variation that is explained by genetic variation (1 = high, 0 = low)

The heritability of eye color is ~x

1

The heritability of heart disease is ~x

0.5

The heritability of the number of eyes is ~x

0

Which personality traits are heritable?

All of them: Big 5, political views, religiosity, sexual orientation, scores on intelligence, all have greater than 0 heritability

Does heritability say anything about group differences?

No! Proof:

Two identical groups of plant seeds are planted. One group is grown in good conditions, while the other group is grown in bad conditions.

Heritability is high for height within each planter. However, even though the group grown in bad conditions has lower heights, there is no heritability between groups.

Parenting matters ___ than you think

less

Obedience to Authority, Sheridan & King

Students were presented with a "cute fluffy puppy" and were prompted to give it a real shock whenever it made a mistake. 77% of college students shocked the puppy despite no obligation to continue.

Milgram experiment

Participants were told to shock another participant when they made a mistake and were played a recording of the person shouting in pain. It was implied that the greater shocks could be lethal. Participants went along 37% of the time. With an ally, they went along even less.

Kitty Genovese murder

37 neighbors of Kitty Genovese did not call the police when they heard her being stabbed.

Bystander effect

People are less likely to help someone when they are in a large group of people vs. when they are alone; diffusion of responsibility.

Diffusion of Responsibility Study

Participants were led to believe they were either alone with another participant or in a large group of people. The participants heard the sound of another participant having an epileptic seizure. 100% helped when alone, while ~60% helped in a large group.

Asch Conformity Experiments

A study on group influence on individual judgment. Participants were placed in a group of actors and asked to say which line they thought was the longest. When the group was unanimously wrong, the participant would conform 36% of the time. When the participant had an ally, they would conform less often.

Minimal Group Paradigm (Tajfel)

Least important thing in common with a group that still makes people feel good. In this study, participants were prompted to count the number of dots on a screen. They were split into two groups: low counters and high counters. Then, they were allotted points and prompted to give $5 and take $3 from a participant. Participants favored their own group and disfavored the other group. This effect was also found in completely arbitrary splits, e.g. flipping a coin.

Categorization

A very fast human skill that is necessary for survival: e.g. what is a peach, chair, lion.

Thin slicing

Fast judgments about people. People can determine talkativeness, politics, lying, psychopathology, and sexuality better than chance from a 6-second silent clip.

Ambady study (lecturers)

Participants were shown silent videos of lectures. Based on their first impression, they gave a rating. These ratings were correlated with the course's overall rating, even for videos as short as 6 seconds.

- interpretation 1: our first reaction is very accurate

- interpretation 2: our first reaction is very sticky

- interpretation 3: our first reaction is self-fulfilling

Implicit Bias (Diallo)

Bias that you don't/can't verbally express. You may not know that you have this bias. Ex. police don't think they're racially biased despite evidence

Finding vs. Looting (Hurricane Katrina)

When white survivors of Hurricane Katrina obtained supplies from grocery stores, AP described their actions as "finding" supplies. When a black survivor did the same, AP described them as "looting" the store. This is an example of implicit bias.

Project Implicit Association Test Description

A test to measure implicit bias in a population (not necessarily individuals). Example:

1. Participant is prompted to press "P" for positive words and black faces. Participant is prompted to press "Q" for negative words and white faces.

2. If the participant already associates positive/black and/or negative/white, then the task is easy, and they react more quickly. If the participant associates negative/black and/or positive/white, then the task is hard, and they react slower.

3. The associations are swapped and the user is prompted to press P/Q for the opposite.

Project Implicit Association Test Findings

On average, white/good and black/bad is faster than black/good white/bad. This effect was found in all races with a difference of 0.5 seconds.

Role of Automatic and Controlled Processes in Misperceiving a Weapon (Payne)

Participants were faster to identify a gun and slower to identify a tool after seeing a black face.

Hiring biases (Dovidio & Gaertner)

Participants were presented with strong, medium, and weak applications for a job. Some applications had "frat" as an activity (assoc. with whiteness), while others had "BSU" listed as an activity (assoc. with blackness). While the activity didn't affect the likelihood of the strongest & weakest applications being accepted, frat was preferred over BSU for the medium application.

Effects of implicit bias are (3)

Fast, ambiguous, subtle

Prisoner's Dilemma

A game where two players can each choose to cooperate or to defect. If both cooperate, both gain +2. If both defect, both get no gain. If one cooperates and the other defects, the defector gains +3 while the cooperator loses -1. The best strategy is to always defect.

Public Goods

A game where there is a magic pot that multiplies the money inside of it and divides it among the group. If one person puts in less than the other people, they individually profit more.

Ultimatum Game

Game where there is a proposer and a responder. The proposer has the job of splitting a certain amount of money, and the responder can either accept the split or say no (giving each player $0). Even though the responder should always say yes to a deal where they get a nonzero amount, participants will say no to an unfair deal.

Spontaneous Giving and Calculated Greed (Rand et al.)

When participants were given less time to play the public goods game, they were more generous, indicating that people are fundamentally good.

How many hours do people spend listening to music/week?

20 hrs

Cochlea

inner ear

Auditory Illusions

- McGurk effect (baa/faa: vision affects audition)

- Green Needle/Brainstorm effect (context -> audition)

- Shepard tone: illusion of an always-increasing pitch

Amplitude of sound

Loudness

Frequency of sound

Pitch

Perfect Pitch

Ability to easily name pitches (like naming colors). 0.01%-0.05% of the population has perfect pitch. However, most people can tell when something sounds "off" without any training.

What did Pinkner mean by saying that music is like cheesecake?

Music has no function or effect aside from pleasure.

Natural History of Song (Mehr)

A study that exposed people to songs from different places/cultures. Participants were prompted to listen to songs and guess their purposes (dance/love/healing/lullaby). People guessed much more accurately than random, indicating that form is function for music. Similar studies were also done in babies, finding the same result (universality of music).

Form and function in music

Form is closely related to function: lullabies are slow/quiet, while dance is fast/loud.

Do babies get sleepier when listening to lullabies? How do we measure sleepiness?

We can measure physical signs of sleepiness: heart rate, pupil dilation. Babies were found to be more sleepy when listening to lullabies.

What animals have music?

Birds, mice, whales, and gibbons sing. Birds dance & have a sense of rhythm.

Mozart Effect

A scientific claim that listening to Mozart makes you smarter. In the 1990s, people were found to perform temporarily better on a spatial IQ test after listening to Mozart vs. relaxation music/silence.

Arguments against Mozart effect

- May have been caused by an increase in arousal (Mozart is more exciting). Energetic classical music was found to cause a greater increase in performance than slow classical.

- The participants were WEIRD college students

- Very short (10-15 sec) effect

Does playing an instrument make you smarter?

No. When controlled for wealth and other circumstances, music classes didn't make elementary school students better at vocabulary or math when compared to art class, or even nothing.

Hartfield and Bersheid

They were two relationship psychology researchers who founded the field. Their research was called "unneeded" by a senator.

Metaanalysis

A type of research paper that analyzes trends in past studies for a wider assessment.

Relationships and survival odds

Over 148 studies on survival odds, the strongest predictor of greater survival was social relationships

Financial cost of the direct and indirect consequences of struggling marriages in the USA is $x

33,000,000,000

Do opposites attract?

No, we are attracted to similarity in personality, attitude, political views, and economic status. We are more likely to interact with people who are similar to us, and thus more likely to form closer relationships with them.

Propinquity

Proximity (physical or psychological)

Major Histocompatibility Complex (MHC)

A protein related to immunity (makes you more or less resistant to different infections). Each person's MHC is unique and determined by genetics. Hypothesized to act as a pheromone.

Major Histocompatibility Complex and Attraction

Scientists hypothesized that we are more attracted to people whose MHC is complementary to ours (so offspring are resistant to a greater variety of diseases). In a study, participants wore white T-shirts for several days. Then, different participants chose one by smell. It was found that MHC compatibility is more complicated (a mix of similar vs. complementary MHC attraction).

What happens to long-distance relationships when they are no longer long-distance?

They have the same relationship quality as geographically close relationships.

Fidelity study

Men were prompted to imagine a romantic partner getting either emotionally or sexually involved with someone else.

- Men were more upset about sexual involvement than emotional involvement.

- Men in relationships were even more upset about physical vs. emotional involvement compared to single men

Benefits of a long-distance relationship (why do LDRs sometimes break up when the distance closes?)

Less jealousy, exposure to each other's flaws, and valued time together more

How do we study relationships?

- surveys, videos (but people act differently when observed)

- VR simulation

- speed dating

4 horsemen of the apocalypse (relationships)

- criticism

- contempt

- defensiveness

- stonewalling

Effect of partner attentiveness on stress

In a study, participants in a VR world were prompted to walk across a scary cliff. Participants thought their partner was in the world with them, but they were seeing a video instead. When the partner in the video was attentive, participants were less stressed. When the partner was not attentive, the participants were more stressed.

Speed dating study results

People like people who like people. People know whether they like someone quickly.

What is different about emotion compared to memory and arithmetic?

Emotions can be easily categorized as positive/negative.

What are the axes of the emotional multidimensional scaling map?

x: valence

y: arousal

Valence

How positive an emotion is (ex. happiness is high, sadness is low).

Arousal

How intense an emotion is (ex. excitement is high, relaxation is low.)

Automaticity of emotions

Emotions are automatic and easy to bring to mind. We know this because they happen even in scenarios where they logically shouldn't.

The Expression of Emotions in Man and Animals

A book by Darwin examining whether people make the same faces when experiencing the same feelings. Concluded that everyone expresses the same emotion with the same expressions. Further evidence: blind people smile.

Evidence that people don't make the same expressions for the same emotion.

People cry when happy, smile when embarassed

Wire mother vs. Cloth mother (and emotion)

Baby monkeys were raised with a cloth mother (a soft fake monkey without food) and a wire mother (a wire fake monkey that gave them food). The baby monkeys spent < 1 hr/day with the wire mother and otherwise sought the cloth mother for comfort, especially when exposed to a scary robot. When the baby monkeys see the scary robot, they scream and cower, appearing to express the same emotions as humans.

Patient SP

She was a patient with bilateral amygdala damage. In a study, she was shown a series of shapes. Whenever a blue square appeared, she was shocked. Her galvanic skin response (a measure of fear) showed that she had no fear from seeing the blue square. In the past, she had been robbed due to having no fear. This brain damage is also associated with less ability to recognize fear in others.

Iowa Gambling Task

Participants were prompted to draw cards from two decks to get money. One deck was better than the other. Control subjects would sample from both decks before recognizing the good deck and choosing only from the good one. Participants with emotional impairment would recognize the bad deck but not avoid it.

Somatic Marker Hypothesis (Damasio)

Emotions constrain the decision-making space, making us more rational.

Capgras' Delusion

A delusion where you believe that all your friends and family are impostors, caused by brain damage. Thought to be caused by a loss of the somatic marker associated with loved ones.

Delusion

A belief that is not logical or connected to other beliefs.

Misattribution of Arousal

A study on how the interpretation of your own emotional state depends on your physical state. Men were approached on a bridge by a female researcher and given a phone number. More men called the phone number from the taller, scarier bridge. A similar effect can be found in caffeine or adrenaline.

How do physical states affect interpolation of events?

Rather than emotions causing physical reactions, physical states can affect how we perceive our own emotions and interpret events.

Maslow's Pyramid (5)

A pyramid organizing the order in which we experience different desires.

- self-actualization

- self-esteem

- love and belonging

- safety

- physiological needs

Barkley Marathon

Example of Maslow's Pyramid: people prioritize sleep, food, and thirst over job and family during the marathon.

Hawaii missile alert

Example of Maslow's Pyramid: visits to pornography website decreased after people received this erroneous alert.

Consumption Adequacy and Autonomy

A study that found that consumption adequacy (physiological needs met) is more important than autonomy (political/economic stability) in determining happiness. People with low autonomy and high consumption adequacy were happier than those with the reverse.

Affective forecasting

How happy we think we would feel in a situation

Does winning the lottery or getting paralyzed make you happier in the long run?

Neither: same level of happiness 1 year later

Dying is unexpectedly positive

In this study, participants were prompted to write a blog post as if they were dying from a terminal illness (ALS). Their imagined blog posts were much more negative than the actual patients' posts.

In another study, participants were prompted to write their last words as if they were inmates on death row. Inmates' actual last words were more positive than non-inmates' forecasts.

Impact bias

Tendency to overestimate the difference of alternatives

Money vs. Happiness

People predict that they would be more upset at a lower salary than people actually are. People predict that they would be happier at a higher salary than people actually are.

Happiness plateaus around 100k salary. After this point, there are diminishing returns.

What do people think they should spend money on?

Save up for something big for yourself.

What should people spend money on to be happy?

- buy experiences

- spend on others

- many small purchases

- avoid comparison

Experiences vs. things

At initial purchase, a thing and an experience give the same amount of purchase satisfaction. Later, the thing depreciates in satisfaction while the experience gains in purchase satisfaction. Buy experiences, not things!

Maximizing vs. Satisficing

Maximizing = looking for the very best

Satisficing = looking for something above a threshold

Positional Concerns

A: Your income is 50k, others earn 25k.

B: Your income is 100k others earn 200k.

Most people choose A because of positional concerns.

A: You have 2 weeks of vacation, others have 1 week.

B: You have 4 weeks of vacation, others have 8 weeks.

Most people choose B because it's an experience.