Between 1924-32 the Hawthorne Works telephone equipment plant of the Western Electric Company was the site of a research program. A series of experiments focused on the levels of illumination and its affect on productivity. What made this interesting was that productivity continued to increase even when the illumination was reduced. It seemed that because the workers knew they were a part of a research they increased their productivity even when the conditions were not conducive to them. This was eventually called the Hawthorne Effect. Even though, the research that was conducted was flawed the knowledge gained on motivation was significant.
Motivation is considered goal-oriented behavior and the underlying motives. Motives arouse and direct our behavior toward some goal. There are three major categories of motives: biological, stimulus, and learned social motives.
Biological motives are things such as hunger, thirst, and physical needs.
Stimulus motives are things such as sensory stimulation, exploration, curiosity etc.
Social motives are behaviors such as achievement, power, affiliation, and other social experiences.
Motivation is behavior that is initiated and directed toward a goal, and varies in intensity and persistence.
Consider a biological motive such as hunger. There are times when you eat because its time and other times when your hunger is such you stop doing something and eat. Consider sleep, there are times when you sleep because you're tired and other times because it is time. The intensity of your behavior to eat or sleep is also, relevant. Psychologists look at motivation via behaviors associated with initiation, direction, intensity and persistence. In research we may manipulate the environment such that behaviors will or will not occur. For example, if a lab rat is not hungry it will probably not push a button to get food. Therefore it would be difficult to train a lab rat to push a button.
Theories of motivation
In the late 1800's the field of psychology initially leaned toward the concept of instinct theory to explain motivation. According to instinct theory people are motivated to engage in certain behaviors because of genetic programming. However, instinct theory began to be viewed as too simplistic and was not able to explain a number of behaviors. During the 1920-30's it began to fall out of favor. Instinct theory was replaced by the concept of Drive theories. This asserted that behavior is motivated by the desire to reduce internal tension caused by unmet biological needs. When particular behavior is successful at reducing tension then it is more likely to be repeated.
The idea is these unmet biological needs drive or push us to behave in certain ways. Clark Hull and Robert Woodworth believed that drives are a triggered by the internal mechanisms of homeostasis. Homeostasis is the principle that the body monitors and maintains itself in a balance of all the systems. And the body is constantly, attempting to maintain this state. If there is loss of homeostasis then there is action to return to it. The intensity of the behavior or actions related to maintaining this balanced state are tempered with the amount of out of balance we are. When your levels of oxygen and C02 are out of balance you initiate a yawning behavior which returns the 02 and C02's balance. This is called a drive. Drive is the impulse that activates behavior to reduce a need and restore homeostasis. Again this was not adequate in explaining all behaviors and situations. Although, this was useful for understanding many types of behavior and motivation.
Incentive theories view behavior is motivated by the pull of external goals, such as rewards. During the 1950's [remember that behaviorism was considered the predominate view of behavior in psychology] psychology began to view motivation as not necessarily involving all of the internal mechanisms. The behaviorists could create or modify many behaviors by manipulating stimulus and or rewards [reinforcement].
Arousal theory holds that you must consider the whole person and to understand how the person regulates his or her arousal level. Arousal is a continuum that ranges from low to high and behavior is motivated by changes in the arousal state which in turn creates behavior to efficiently address the arousal state.
Donald Hebb  proposed the we are motivated to maintain an optimum level of arousal. In other words, if our arousal level drops too low we are motivated to do something about it. It is also noted that the relationship between arousal and performance is an inverted U and there is a finite point in which too much arousal will cause a deterioration in performance as well as too little arousal.
Abraham Maslow proposed the concept of "Hierarchy of Needs. Maslow was a humanist psychologist that did not discount the biological components of motivation but proposed that there were basic needs, psychological needs and self-fulfillment needs. He develop the concept of the hierarch of needs:
Physiological needs: such as food, water, warmth, rest, etc.
Safety needs: security, safety, shelter etc.
Belongingness: intimacy, friendships, social relationships
Esteem needs: prestige, feelings of accomplishment, social acceptance.
Self-actualization: achieving ones potential
Maslow approached this by studying people who where view as successful and well adjusted.
The cognitive theorists would view motivation based on physical needs or arousal, learned behavior, and maybe non-conscious not only wants or wishes but also on how we think. Your thinking controls how you act and when you act. If you think you are in danger you will behave differently than if you don't think you are in danger. The expectancy-value theory, developed by Julian Rotter  argued that behavior is the result of our expectations of achieving goals and the value that those goals have for us. Attribution is an other cognitive process related to motivation. Forces within the person [disposition forces] and forces in the environment [situation forces] interact and a person does or doesn't do goal directed behavior.
Uses the principles of natural selection to study how adaptive human behaviors and psychological mechanisms have developed. Evolutionary psychology studies cross culture in an attempt to discover the commonality of human behavior.
Consider eating. There is probably many times when you eat because you are physically hungry. However, there are probably other times when you eat not because you are hungry but for something else. Have you ever over eaten? If you were motivated to eat only by the biological need to eat how would you explain eating past your hunger quenching level?
The motivation to eat
The motivation to eat is influenced by psychological, biological and/or social and cultural factors.
Oral stimulation, stomach signals, CCK [a hormone called cholecystokinin] that acts as a neurotransmitter that signals the receptor sites in hypothalamus that are related to eating and hunger. The glucostatic theory of hunger, proposed by Jean Mayer asserted that hunger occurs when the glucose metabolism in individual cells falls below a certain level which in turn stimulates us to eat. The Lipstatic theory proposed our hunger is regulated by the storage of body fat. And that for some the storage of body fat manifests itself in over eating and obesity. Richard Nisbett suggested that there is a set-point theory of obesity. He suggests that there is a point in which the hypothalamus reacts to blood sugar level and for some this point is higher.
It has also been suggested that people who over eat may have low levels of the neurotransmitter serotonin. And msy over eat carbohydrates to compensate.
Psychological reasons to eat and over eat:
The psychodynamic view is eating is related to security, safety and maybe driven by unconscious desires and wishes. Eating maybe compensating for some unconscious psychic need. An example to this approach might suggest that a person who over eats and becomes heavy is putting a layer of fat on them to insulate them from their environment or to make him or her less attractive in order to avoid people. [this is a very simplistic manner in explaining this concept.]
The behaviorists would explain over eating as a learned behavior via direct reinforcement, imitation, and other learned behavior. And that eating is a self rewarding behavior.
The cognitive theorists would consider overeating as having its roots in the cognitive processes and that we think or believe certain things and eating is the manifestation of those cognitive processes.
Two major eating disorders are anorexia nervosa and Bulimia nervosa
Anorexia nervosa is an eating disorder in which the person becomes severely underweight because of self-imposed restrictions in eating. The APA diagnosis of this disorder includes the intense fear of being overweight and the loss of 15% of body weight without any physical problems that would account for it. Although both sexes are represented in this disorder more females present with this disorder. It is estimated 1% of the female teenage population is affected by anorexia. The person literally starves themselves, often times, to death. The anorexic will either ignore or is not aware that they are not ingesting enough to maintain a healthy state. Their self-perceptions are extremely disoriented. They view themselves as appearing differently than others. When they look in the mirror they appear to not see themselves as others do. They see fat where there is none, they a poor at self monitoring and evaluation. Causes seem to be related to societal pressures to be thin as well as culture as that it is a disorder that is mainly in the Western Americian/Europeon culture.
Bulimia nervosa is a eating disorder that is manifested by eating large amounts of calorie rich food in a short time then purging the food by vomiting or using laxatives. This is contrasted to anorexia as often individuals with bulimia are within normal weight ranges. Sometimes the bulimic will ingest as much as 50,000 calories at one time in a short period. There are periods of binge eating which occur in secret. As with anorexia, cultural pressures seemed to be related as well as faulty thinking about food intake, distorted body perception and a tendency toward perfectionism. Also, worth noting is there seems to be genetic factors related as well.
Curiosity and exploration
The curiosity motive causes us to seek out a certain amount of novelty and complexity, and with not apparent motivation, we seek out and explore new environments. Young children prefer complex patterns over simple ones.
Some of the research suggests that our level of curiosity motive stays stable throughout our lifetime. The motivational theory of competence state that we are motivated to interact successfully with our environment.
Intrinsic motivation is behavior that results from interpersonal factors.
Extrinsic motivation is behavior that results for extra-personal factors. [what we can get]
Edward Deci  proposed his theory of intrinsic motivation. He suggested that we need to feel competent in controlling and interacting with our environment. And self-determination is can increase intrinsic motivated behavior.
Learned Social Motives
Henry Murray  contended that social motives are largely learned and he developed a list of basic social motives:
He and others suggest we are taught to maintain a certain level of the above. Further, we are taught and acquire behavior that allows us to achieve our learned social motives.
The level of intensity by which the person attempts to meet the learned social motives is determined both by individual and familial influences as well as by cultural and societal influences.
Research of fear of failure indicates that people who score low on the need for achievement tests also tend to have a high fear of failure.
Also, it has been shown that the need for affiliation increases during period of anxiety. Misery needs company. When given the choice of waiting in an anxious situation in a nice environment and alone or in a poor environment with others most would choose the later.
Psychology a Connectext 4th edition, Terry F. Pettijohn
Discovering Psychology, Don Hockenbury & Sandra Hockenbury
Social Psychology, 5th edition, Deaux Wrightsman