Dopamine is a neurotransmitter that interacts with the brain's reward and pleasure centers, while oxytocin and vasopressin are known as the "hormones of attachment". The Pink Lens Effect refers to the feeling a person in love often has that convinces him/her that his/her loved one is perfect and can do no wrong.

The Commons Dilemma, or Tragedy of the Commons, refers to the tendency of groups (or individuals) sharing a common resource to each prioritize their own self-interest and claim more of the resource than is their fair share. This tendency can be combatted by teaching everyone that the needs of their neighbors should be valued as much as their own, and that they should act accordingly.

Paul Ekman's work on universal facial expressions asserts that most people recognize emotions similarly. Ekman's primary example is that smiles are almost universally recognized as expressing happiness across cultures. While cultural norms and styles of communication may radically the frequency of a given expression, or the social context in which they are made, the fundamental expression is recognized across cultures.

Colin's actions do not line up with his beliefs in this scenario and that causes a sense of conflict or tension, which psychologists label cognitive dissonance. According to this concept, Colin will be motivated to resolve the dissonance by either changing his beliefs or his actions. Hopefully, he will choose to work on his actions. Of note, low psychological absorption is a made up concept. Reactance has to do with our sense of freedom. Self-immunization involves minimizing our failures.

It is a well-known fact in social psychology, particular in the study of romantic relationships, that women are choosier about mates than men. This is because there is a higher social and biological risk for women who pick bad mates (e.g. social stigma and the biological costs associated with rearing children alone).

Physical attractiveness has an affect in nearly every part of life. Due to psychological phenomena like the halo effect (e.g. when one character trait of a person leads others to assume other traits about them), physical attractiveness can lead individuals to believe that someone seems more intelligent, likeable, or competent. In terms of job interviews and average salary, studies have shown that conventionally attractive people tend to get jobs more easily and make more money. And, of course, physical attractiveness is one criterion that people consider important with regard to dating and relationships.

Social exchange theory is the idea that social relationships are an exchange in which a participant tries to maximize benefits and minimize costs (e.g. if the costs get too high or the benefits too low, then an individual will end the relationship). 

While intriguing, the other choices are incorrect. Comparison level for alternatives is the idea that people tend to stay in a relationship if they perceive that their relational outcomes would not be better in a different relationship and leave if they believe that their outcomes would be. Equity theory is the idea that people are happier in relationships where there is fair give and take by both people in the relationship.  The halo effect is the idea that people tend to overgeneralize one character trait; for example, if someone is handsome, other people might overgeneralize that positive attribute and assume he's also funny and hardworking. Mere exposure effect is the idea that people tend to like things or people they are familiar with/exposed to more often. 

Comparison level for alternatives is the idea that people tend to stay in a relationship if they perceive that their relational outcomes would not be better in a different relationship and leave if they believe that their outcomes would be better (such as a nicer partner).

While intriguing, the other choices are incorrect. Equity theory is the idea that people are happier in relationships where there is fair give and take by both people in the relationship. The halo effect is the idea that people tend to overgeneralize one character trait; for example, if someone is handsome, other people might overgeneralize that positive attribute and assume he's also funny and hardworking. Mere exposure effect is the idea that people tend to like things or people they are familiar with/exposed to more often. \ Social exchange theory is the idea that social relationships are an exchange in which a participant tries to maximize benefits and minimize costs; if the costs get too high or the benefits too low, they will end the relationship. 

Equity theory is the idea that people are happier in relationships where there is fair give and take by both people in the relationship. 

While intriguing, the other choices are incorrect. The halo effect is the idea that people tend to overgeneralize one character trait; for example, if someone is handsome, other people might overgeneralize that positive attribute and assume he's also funny and hardworking. Mere exposure effect is the idea that people tend to like things or people they are familiar with/exposed to more often. Social exchange theory is the idea that social relationships are an exchange in which a participant tries to maximize benefits and minimize costs; if the costs get too high or the benefits too low, they will end the relationship. Comparison level for alternatives is the idea that people tend to stay in a relationship if they perceive that their relational outcomes would not be better in a different relationship and leave if they believe that their outcomes would be.

The halo effect is the idea that people tend to overgeneralize one character trait; for example, if someone is handsome, other people might overgeneralize that positive attribute and assume he's also funny and hardworking.

While intriguing, the other choices are incorrect. Mere exposure effect is the idea that people tend to like things or people they are familiar with/exposed to more often. Social exchange theory is the idea that social relationships are an exchange in which a participant tries to maximize benefits and minimize costs; if the costs get too high or the benefits too low, they will end the relationship. Comparison level for alternatives is the idea that people tend to stay in a relationship if they perceive that their relational outcomes would not be better in a different relationship and leave if they believe that their outcomes would be. Equity theory is the idea that people are happier in relationships where there is fair give and take by both people in the relationship.