Kurt Lewin classified conflicts based on whether they posed desirable or undesirable consequences. In an approach-approach conflict, a person is faced with two desirable options. For example, a person must choose between going to one of two restaurants that he enjoys. In an avoidance-avoidance conflict, a person is faced with two undesirable options. For example, a person has to decide between spending his afternoon cleaning or studying for an exam. In an approach-avoidance conflict, a person is faced with one option that has both desirable and undesirable consequences. In the case of this example, Sam is faced with both pros and cons associated with joining the swim team. In a multiple approach-avoidance conflict, there are several conflicts that pose both pros and cons. Last, the term ambivalent is not used in Lewin's classification. 

Intrinsic motivation is defined as motivation to complete a behavior because it is internally satisfying to the person. On the contrary, extrinstic motivation is defined as motivation to complete a behavior to acquire extrinsic rewards (for example, money, food, or elevation of status). 

Maslow's hierarchy of needs ranges from physiological needs (at the bottom of the pyramid) to self-actualization needs (at the top of the pyramid). Self-actualization involves achieving one's unique potential, and is much more spiritually oriented than the lower levels.

Intrinsic motivation involves internal motivating factors that keep us focused on completing a task. This does not include external rewards, like a piece of candy or a bonus at work. Thus, studying for the pure sake of learning is an example of intrinsic motivation.

Marie is faced with two undesirable outcomes: riding a ride she does not like or inviting the mockery of her friends. Marie would prefer to avoid both of these outcomes, thus she faces an avoidance-avoidance conflict.

Psychoanalysts use both of these projective tests in the attempt to access a patient's unconscious mind. The idea behind their use is the possibility that what sense the patient makes of an inkblot or the story they create behind an ambiguous picture will reveal hidden emotions, conflicts, or desires that have been troubling him/her without his/her direct knowledge.

Aptitude tests are used to determine an individual's underlying capacity or talent at a task; aptitudes can be mental or physical. Intelligence tests are used strictly in an attempt to measure mental acuity. Achievement tests are used to test both skill and aptitude. Morality tests are used to assess individuals' response to specific, moral situations.

Intrinsic motivation is when someone completes an action because the action itself is an enjoyable process. This contrasts with external motivation, where an action is completed in order to gain external reward or avoid a negative external consequence. If I'm painting a landscape because I need money and someone will buy my painting, I may enjoy painting it, but this will have been an externally motivated behavior. If I engage in an action like reading, drawing, or the like, because it is pleasurable and there is no expectation of reward, this is intrinsically motivated.

A primary drive is a drive that is completely unlearned, something that any human will inherit regardless of their socialization, upbringing, or background. Primary drives are concerned with survival and reproduction. These drives for humans are hunger, sex, thirst, sleep, and bathroom needs. All of these ensure the health, maintenance, and reproduction of the human species.

William Masters and Virginia Johnson noted in their study on the sexual response cycle that sexual desire can be present even if one does not have the ability to have sex anymore.

The Set Point Theory is the theory that the hypothalamus wants to maintain a certain ideal body weight. Once we reach that set point, our metabolism kicks in to burn off the excess food.