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Lecture 27-Motivation. Having covered the cognitive psychology of knowledge -- sensation,
perception, learning, memory, and thinking -- and said something about the effect of
psychology of emotion, it remains for us to say something about the conative psychology
of motivation. Why do people engage in various activities -- eating, drinking, bowling, fly
fishing, marathon running, writing poetry, playing the recorder -- even when they don't
do these things particularly well? Psychologists often explain peoples' behavior in terms of
their motives, but in fact explaining behavior in terms of the person's motives is something
that all of us do. Motives are a critical ingredient in Western concepts of law and
justice. People may do bad things, but they haven't committed a crime unless the evil
deed is accompanied by an evil intent.
A motive can be defined as an internal state that causes the organism to initiate, choose,
or persist in behavior that's directed toward, or away from some goal. The motivational state
of hunger causes us to eat, the motivational state of thirst causes us to drink, and the
motivational state of fear causes us to avoid something. Approach and avoidance are the
essential ingredients in any motive. We usually think about motivational states in terms of
the organism's needs, or wants, or goals, or desires. These are not all quite the same
thing. We can need something that we don't really want. And in this consumer-driven society
we can want a lot of stuff we don't need. But for the most part psychologists use these
terms more or less interchangeably.
Many of the motives that underlie our behavior have a biological basis, and many of these
biological motives are based on what the 19th-century French physiologist Claude Bernard called
homeostatic regulation -- that is, the regulation of the organism's internal environment of
physiological state. This is accomplished by a set of physiological mechanisms by which
the body maintains a constant internal environment, despite changes in the external environment.
These mechanisms are so precisely tuned that Walter Cannon, an American physiologist, called
them "the wisdom of the body". The basis of homeostatic regulation is negative
feedback, meaning that changes in the environment instigate actions that have the effect of
stopping or reversing the changes themselves. A familiar example is a thermostat. When a
room gets too cold, the thermostat turns on the heat and then it turns off the heat when
the room is restored to its proper temperature. And when the room gets too hot, thermostat
turns on the air conditioning, and then turns the air conditioning off when the room is
cooled down. In positive feedback a change produces a process that magnifies the change
instead of reducing it. A familiar example is feedback at a rock concert where a microphone
picks up sound from a speaker and feeds that sound back into the amplifier and then to
the speaker again creating screeches and wails. Don't confuse the technical concepts of positive
and negative feedback with things like reward and punishment. Negative feedback stops or
reverses the change that produced it. Positive feedback magnifies that change.
We've already seen one example of homeostatic regulation by negative feedback, which is
the antagonistic relationship between the sympathetic and parasympathetic divisions
of the autonomic nervous system. In response to environmental stressor the sympathetic
nervous system activates the body preparing it for flight or fight, to tend or befriend.
This drains bodily resources like blood sugar, leaving the parasympathetic nervous system
to kick in to dampen sympathetic activity, slowing down the drain of resources. And after
the stressor has disappeared, the parasympathetic nervous system continues to operate, restoring
the organism's internal environment to its optimal level.
As I say, many of our basic biological motives operate on a principle of homeostasis. A clear
example is hunger, and the eating behavior that it stimulates. Hunger is based on mechanisms
that keep track of body weight and glucose, or blood sugar. For example, the liver tries
to keep blood glucose levels roughly constant. If there's too little glucose in the bloodstream,
signals from the liver will initiate eating behavior. If there's too much glucose in the
bloodstream, the liver will send out signals to terminate eating behavior. At the same
time, the liver will convert excess glucose to glycogen and fatty acids for later use.
If there's too little glucose in the bloodstream the liver will convert stored glycogen and
fatty acids back to glucose. Under stress, an organism will deplete blood sugar by virtue
of sympathetic arousal. And because it's engaged in flight or fight, or tend and befriend,
it will not have time to eat. That's when the parasympathetic nervous system kicks in
to convert glycogen back into glucose. Besides the liver there are also glucoreceptors in
the stomach, the duodenum, part of the small intestine and fatty tissue in the body. And
there are also glucoreceptors in the hypothalamus. The activity of gluco-receptors is a very
good example of what Sherrington meant by interoception. Afferent impulses run from
the liver, the stomach, the duodenum, the fatty tissue, and the hypothalamus to the
central nervous system, to provide information about the organism's internal environment,
blood sugar levels. They are technically sensory impulses. We're not conscious of these sensations,
but they're sensory impulses, afferent impulses, nonetheless.
In the classic dual-center theory of feeding one portion of the hypothalamus, the lateral
hypothalamus seems to serve as a go center for feeding, initiating eating behavior when
glucose or body weight drops below normal levels. Another portion of the hypothalamus,
the ventromedial portion, seems to serve as a stop center, terminating eating when body
weight climbs too high. Another approach to understanding hunger and
feeding focuses on calories and body weight (perhaps body mass), rather than blood sugar.
According to a highly popular theory, organisms will consume just enough calories to maintain
their body weight around their genetically determined setpoint. If their weight drops
too much, they'll begin eating until their weight returns to its setpoint. If they gain
too much weight they'll stop eating, or eat less, until their weight returns to its setpoint.
Now note that by "setpoint" we do not mean some medically determined, optimum weight
such as a body mass index of 24 or whatever. Everybody has their own setpoint, determined
by genetics and other aspects of family history. Some people have very low setpoints and are
predisposed to be thin. Others have higher set points and are predisposed to be fat.
But body weight is not all in the genes. Changes in the environment, like the food supply,
can make people thin or fat even though they might have average setpoints under terms of
their normal diets. Moreover, changes in behavior, like exercise, can also alter setpoints. But
whether we're talking about glucose, or calories, or body weight, the liver, or the hypothalamus,
it's all homeostatic regulation by means of negative feedback.
There's a similar account we can give for thirst. The feature of the internal environment
that's regulated by drinking is the concentration of salt in intracellular fluids. When cells
become dehydrated, or the concentration of salt inside cells gets too high, the organism
is stimulated to drink until the proper levels of hydration are restored. According to the
double-depletion hypothesis, there are actually two different kinds of thirst. One controls
intracellular fluids, while a similar one controls extracellular fluids -- like in blood
plasma. In cases of over-hydration, where there's too much water inside or outside cells,
the organism will stop drinking for a time.
And also of body temperature. For humans normal body temperature is 98.6 degrees -- for some
individuals its a little lower or it's a little higher. When an animal's body temperature
gets too high, the parasympathetic nervous system initiates a number of behaviors, including
vasodilation which brings circulating blood nearer the surface of the body where it can
be cooled; also sweating and panting, which also have the effect of lowering body temperature.
When body temperature gets too low, the same system initiates vasoconstriction, which keeps
circulating blood closer to the body's core. If body temperature is too high, animals will
move away from a source of heat; if body temperature is too low, they'll move towards that source
-- which is why your cat can often be found sleeping on your radiator.
Hunger, thirst, and thermoregulation exemplify homeostatic regulation via negative feedback.
But there's obviously more to these motives than homeostatic regulation. We don't eat
just to restore body sugars and we don't drink just to restore cell fluids. For example,
eating and drinking are also social behaviors. We engage in them as ways of being with other
people and we also do them when other people are doing them. There's also an emotional
overlay to eating and drinking. We eat and drink when we're sad, for example. And there's
a perceptual-cognitive overlay. We can become hungry and thirsty, or at least we can eat
and drink, simply by virtue of the presence of food or drink in the environment. Amnesic
patients like patient H.M., who cannot remember recent events, will continue eating when served
several meals in succession -- even though they've already ingested their fill of calories.
They forget they've just eaten lunch and they eat another lunch, just because it's lunchtime.
And the fact that it was lunchtime, and food was being offered, made them eat.
There are other motives that seem not to involve homeostasis at all. For example, aggressive
behavior is stimulated by the presence of external threats, and also just by high levels
of testosterone in the blood stream. But the goal of aggression is not to reduce testosterone
levels; it's to defend one's territory against one's competition for mates.
Similarly, in non-human animals, mating behavior is tightly regulated by sex hormones -- estrogen
in females and testosterone in males, and occurs only at certain points in the female
estrous cycle. After ovulation occurs, the female rat will be receptive to *** overtures
from males, and will even signal to potential partners that she's willing to mate. But at
other points in the cycle, the same female will vehemently reject the same male if he
tries to mate with her. As with aggression, mating behavior is under hormonal control
to some extent, but the behavior has no effect on hormone levels. They rise and fall naturally
as part of the estrous cycle, no matter what the animals do.
Well, actually that's not quite true. The female rat's courtship behavior actually triggers
the release of testosterone in the male. And copulation will also trigger the release of
progesterone in the female. This increases the likelihood that the fertilized egg will
be implanted in the uterus. Neither of these effects represents homeostatic regulation,
however, which is the basic point. Not all motives work by homeostasis.
And it's important to point out the obvious, which is that human *** behavior is, to
a very great extent, freed from hormonal control entirely. That is to say, humans mate regardless
of whether the hormonal circumstances are right for reproduction. In fact, humans are
probably more likely to mate when they can't reproduce than when they can. Sex among humans
is motivated behavior but it's not necessarily motivated by rising hormone levels. It's also
motivated by the feelings of pleasure, affiliation, and intimacy that we get from sex, and even
sometimes by power -- motives that play little or no role in the *** behavior of non -human
animals.
These biological motives -- hunger, thirst, thermal regulation, sex -- are the basis of
what's known as primary reinforcement. You'll remember from our discussion of learning,
Thorndike's laws of learning, which included the law of effect -- that responses that are
rewarded are strengthened and responses that are not rewarded are weakened. And also Thorndike's
law of readiness, which basically says that organisms learn when they're energized by
a motivational state, which in turn serves as the basis for reward. Hungry rats will
push a lever in an operant chamber. Hungry pigeons will peck a key. So these biological
motors serve as the basis for primary reinforcement. But other stimuli can take on motivational
properties simply by virtue of being associated with a primary reinforcement. A rat who's
rewarded with food in a white goal box, and never rewarded in a black goal box, will head
for the white goal box even when there's no food present. Apparently the white goal box
has taken on reinforcing properties by virtue of its association with a primary reinforcer.
This is what's known as a conditioned, or a secondary reinforcement. Monkeys will work
for grapes, they love grapes. But monkeys will also work for poker chips that they can
exchange at a later time for grapes. The grapes are a primary reinforcer, the poker chips
are a conditioned secondary reinforcer. Money, in these terms, is a secondary reinforcer.
It doesn't do anything for us all by itself, but with money, we can buy food and drink
and other things that we need (or want).
Primary motives are in some sense innate. Secondary motives are acquired through experience,
through learning. And, in this context, emotions can serve as sources for secondary motivations.
Hunger, thirst, and sex are innate drives, but love for a particular person, or the fear
of a phobic object, are in some sense learned. We tend to approach the things that we've
learned give us pleasure, and we tend to avoid the things that we've learned give us pain.
Classical fear conditioning is a good model for an emotional response that's acquired
through learning, and escape and avoidance learning are good examples of how acquired
emotions can translate into motivated behavior.
Some secondary motives are acquired through learning, but other secondary motives seem
to reflect the operation of innate, automatic, physiological processes. Consider, for example,
the peculiar temporal dynamics of affect as noted by Richard Solomon and his associates.
The person's initial response to an emotionally arousing event is an increase in positive
and or negative emotion -- happiness or sadness or whatever. But as the event continues the
emotional state doesn't remain at this initially high level. Rather the level of emotional
arousal decreases and then stabilizes at some level. When the arousing event terminates,
the emotional state doesn't just drift back down to zero. Rather, very often, the person
experiences the sudden onset of the opposite emotional state. Fear is replaced by happiness.
Pleasure is replaced by sadness. This opposite hedonic state gradually diminishes. And the
person eventually does return to baseline, to zero.
Again, this doesn't always happen, but it happens often enough to be a source of puzzlement
and to require explanation. This interesting pattern, in which one affective state replaces
another affective state has been explained by the opponent-process theory of acquired
motivation -- a theory that's modeled on the opponent-process theory of color vision proposed
by Jameson and Hurvich. The basic idea of the opponent process theory is that each emotional
state -- lets call it the A state -- automatically generates its opposite -- call it the B state.
The B state is, in these terms, a slave to the A state. Solomon proposed that the person's
emotional experience at any particular moment in time reflects the joint effects of the
A and B opponent processes. In theory, the B state recruits more slowly than the A state.
Thus, the person's initial emotional reaction of a pure A state tapers off as the B state
kicks in and counteracts it. This is the phenomenon noted by Hans Selye in his description of
the first two phases of the general adaptation syndrome, in which the initial state of gross
emotional reaction is followed by decreased emotionality. Solomon also proposed that the
B state dissipates more slowly than the A state. Thus, when the original emotional stimulus
is removed, the A state terminates quickly but the B state remains in effect. In this
way, the original emotion is replaced by its hedonic opposite. Finally, Solomon proposed
that the B state strengthens with repetition. As it strengthens, it can effectively reduce
the A state to near-zero levels, but this reflects the opposing effects of a correspondingly
large B state.
The entire pattern of opponent processes can be illustrated with respect to drug addiction,
as in addiction to morphine or ***. The user's initial dose of morphine produces a
feeling of intense euphoria, the high, which we'll label the A state. As the morphine wears
off, the high is replaced by the negative feelings of withdrawal: the person doesn't
just go back to zero -- and we'll label this the B state. Repeated doses of the drug, however,
lead to tolerance. It takes more of a dose to achieve the level of the initial high.
This is because the slave B state is strengthened by the repeated elicitation of the A state
by the drug. The B state counteracts the A state. So it takes correspondingly larger
doses of the drug to overcome the B and achieve the high of the A state. But paradoxically,
every dose of the drug strengthens the B state. This initiates a vicious cycle in which the
more you dose with the drug, the less likely you are to feel the euphoric high, and the
stronger will be the negative state of withdrawal. Thus occurs the paradox of drug addiction:
addicts aren't seeking the high of the drug anymore; rather, what they're really trying
to do is avoid the lows of withdrawal. If this cycle is perpetuated as the addict takes
bigger and bigger doses in an attempt to avoid the withdrawal, the inevitable result will
be a lethal overdose. This is because the physiological effects of narcotics are to
depress vital functions like heart rate. So in seeking to achieve a high against the effects
of tolerance, the person overdoses to the point of death. This outcome is inevitable
if the addictive cycle is allowed to continue. And if you think about it, something resembling
the high, withdrawal, tolerance, and addiction can be experienced while eating potato chips
and similar salted snacks. The first chip, or more correctly the first handful of chips,
produces a kind of high, but this wears off resulting in a kind of craving and then redosing
--another handful, and another, and another, until the whole bag is finished. Watch people
at the next party you're at. Watch yourself at the next party you're at. Physiologically,
the addiction to salted snacks shows strong parallels to the addiction of morphine. This
salted nut phenomenon is the origin of the old advertising slogan for Lay's Potato Chips,
"Bet you can't eat just one!". And something similar happens with chocolate these days.
On a different scale, the same kind of effect can be experienced by the so-called "runner's
high", and similar effects of extended aerobic exercise - jogging, running, swimming, dancing
- things like that -- in well-trained athletes. Aerobic exercise, extended aerobic exercise,
obviously produce a prolonged stress on the body -- the less so to the degree that the
person is trained for the event. But at the finish line, as the exercise ceases, the athlete
experiences a flush of exhilaration and euphoria. In this case a negative state A is replaced
by the positive state B of the runner's high.
So some acquired motives are derived from basic biological motives through learning,
and others seem to be derived from basic biological motives through a physiological process like
the opponent process. The infant's attachment to its mother, father, or other caretaker
has sometimes been offered as another example of a derived motive. For example, it has been
proposed that infants become attached to their mothers and other caretakers because their
mothers and other caretakers provide them with food. It turns out, though, that this
just isn't true. In a famous series of experiments, Harry Harlow raised infant rhesus monkeys
in isolation from their parents. Each monkey's cage contained two mannequins -- one built
of wire and the other one wrapped in soft terry cloth. The wire figure also had a ***
that the infant could suck on to get milk, but the terry cloth mannequin didn't have
anything like that. Even though the wire mother provided the nourishment, the infant spent
much more time cuddling with the terry cloth mother, who didn't. And when the infants were
frightened, as if by a loud noise, they ran to the terry cloth mother and clung to her,
not the wire mother. Harlow, proposed that what these infants were looking for was contact
comfort, a social motive that was independent of basic biological needs for food and drink.
The need for contact comfort isn't derived from anything else. It's a basic biological
need.
Perhaps the most famous argument that human social motives were all derived from basic
biological motives was made Sigmund Freud. Freud's fundamental assertion was that personality
is rooted in a conflict between instinctual forces on the one hand, and environmental
forces on the other. He defined an instinct as a mental representation of somatic excitation
-- that is, as a wish that expresses an innate bodily need. This instinct drives behavior
intended to satisfy the physical motive -- and thus, to reduce the original need. It's a
tension-reduction model; it's very closely related to homeostasis. Freud called this
endless cycle of excitement and quiescence, of tension and tension-reduction, the repetition
compulsion. In his early writings on the subject, Freud offered a division between the life-maintenance
instincts and the *** instincts. The former consists of biological needs that are necessary
for individual self-preservation. The *** instincts consist of needs, still biological
in nature, that are necessary for the preservation of the species as a whole rather than any
particular member of it. For the individual the *** instincts are important only in
that they give pleasure. Freud paid little or no attention to the life-maintenance instincts
because he observed that they were rarely the source of conflict and anxiety. However,
conflict and anxiety did seem to surround the *** instincts and Freud gave a special
name -- libido -- to the energy associated with them.
Later in his career Freud proposed a new classification of the instincts. Eros, derived from the Greek
word for love, included the life and *** instincts. They're concerned with the continuity
of life. Thanatos, derived from the Greek word for death, is the death instinct. Freud
held that the products of Eros are love and sex, while the products of Thanatos are hate
and aggression.
Perhaps the most comprehensive listing of human social motives came from Henry Murray,
an American psychologist. Murray was influenced by Freud, but his theory moved far beyond
Freud's narrow focus on the biological instincts of sex and aggression. But he agreed with
Freud about the centrality of motives in human mental life and personality. Murray argued
that individual differences and behavior were determined by the interaction of personal
needs with environmental press. A person's academic, athletic, or business success might
be determined by his or her need for achievement, but this need does not determine success directly.
Rather, it interacts with features of the environment such as the level of family support.
With relatively low levels of family support, a person with high levels of achievement motivation
might nonetheless fail to achieve in life. By the same token, even slackers, with low
levels of achievement motivation might succeed, by virtue of family characteristics such as
wealth or reputation. Murray produced a long list of some 20 human
social motives or human needs. But subsequent research in Murray's tradition focused only
on three -- what are known as the three great social motives of achievement, power, and
affiliation. The need for affiliation was subsequently re-characterized as the intimacy
motive.
Yet another view of human motivation was offered by Abraham Maslow, one of the pioneers of
what has come to be called humanistic psychology. In Maslow's theory, human behavior is motivated
by a hierarchy of needs, in which some needs have priority: they must be satisfied before
other, higher, needs can be satisfied or even expressed. At the lowest level of the hierarchy
are obvious biological needs such as hunger and thirst. After our basic physiological
needs have been met, the next need to emerge is for freedom from danger -- meaning not
just physical danger, but also psychological threats to stability and order.
Once the need for safety has been addressed, then Maslow believed that people were free
to form attachments of various kinds -- to seek friends, to find a spouse, to affiliate
with various social groupings. The next need in the hierarchy is self-esteem, or the need
to feel good about ourselves, and for others to hold good images of us in their minds.
The highest level of need, in Maslow's view, is what he called the ongoing actualization
of potentials, capacities, and talents as fulfillment of mission, as an unceasing trend
towards unity, integration, or synergy within the person. Or, put another way, referring
to people in general, what a man can be, he must be. This need we may call self- actualization.
Maslow admitted that very few people are lucky enough to be able to devote all their energies
to self-actualization, much less actually obtain it. But he did insist that obtaining
self-actualization is the highest of all human needs.
Maslow believed that people like Albert Einstein and Mahatma Gandhi actually achieved self-actualization.
But for the rest of us, he provided a kind of checklist of the attributes displayed by
self-actualized people: first, realism, the ability to perceive reality accurately and
fully -- to accept ourselves as we are and to accept others as they are; spontaneity
-- openness, simplicity, naturalness, a well-developed sense of humor; external problem-centered
focus -- a concern with the world outside, rather than with ourselves; autonomy, an ability
to accept and enjoy other people without needing them; a desire for privacy, the desire to
set one's own goals and values; ethical sensitivity, an awareness of the ethical implications of
one's actions. And then, finally, openness to experience: a tendency toward creativity
and productiveness; taking pleasure in experience just for its own sake; and having quasi-mystical
peak experiences. For Maslow, as with Freud, these social needs
were biologically based. It's simply part of our human nature that we strive for safety,
love, belongingness, self-esteem, and ultimately self-actualization. But these needs are felt,
expressed, strived for, and satisfied in an expressly social context.
Maslow's hierarchy of needs raises the distinction between two different kinds of motivation.
What we've been talking about so far can be characterized mostly as cases of extrinsic
motivation. Here, a person or another organism engages in some activity in order to achieve
some specific goal or to satisfy some need. We eat in order in order to satisfy our hunger.
We drink in order to satisfy our thirst. We do other things in order to achieve freedom
from danger. Or to attach ourselves to other people. Or to obtain self-esteem. But then
there's intrinsic motivation, which refers to a person's desire to engage in some specific
activity without any promise or prospect of reward. If you think about the question with
which we began this lecture -- why do people engage in various activities, bowling, fly
fishing, marathon running, writing poetry, play recorder, or whatever? Sometimes we engage
in these activities in order to achieve some other end, a professional bowler is trying
to make money. An amateur bowler is trying to make friends, or score some points on some
friends. We write poetry to get published and become famous. But other times, we do
these things just because we want to -- just because they're satisfying in and of themselves.
Intrinsic motivation refers to a person's desire to engage in some specific activity,
without any promise or prospect of reward. The idea of intrinsic motivation didn't occur
to most psychologists until relatively recently, the latter half of the 20th century. This
is because most psychologists, up until then, were under the influence of Thorndike's Law
of Effect and its corollary, the Law of Readiness -- that responses, behaviors, were strengthened
when they were rewarded, and that the organism's motivational state of hunger, or thirst, or
whatever sets the conditions for what would be rewarding. But you'll also remember that
Edward C. Tolman's studies of latent learning show that reinforcement -- reward -- wasn't
necessary for learning to occur. Still, even Tolman thought that reward controlled behavior
-- that is the organism's acting on what it's learned.
The implication is that behavior is motivated by rewards and punishments. But it turns out
that that's not necessarily the case, even for animals. Consider some research by Harry
Harlow, who presented rhesus monkey with wooden puzzle blocks and other kinds of puzzles.
In one condition, the animals were rewarded with food for making correct moves toward
solving the puzzle. In the control condition, there was no reward. In general Harlow found
no differences in performance between the two conditions. And, contrary to Thorndike's
law of effect, hunger actually interfered with performance. When the monkeys were not
hungry, but received food as reward, they simply stored it for later access. Harlow
concluded that the monkeys were intrinsically motivated to solve the puzzles. They did so
even without the promise or prospect of reward. They were motivated to solve the puzzles for
their own sake, just for the sheer whatever, pleasure, of solving puzzles.
Similarly, in Maslow's theory, the self-actualized person takes pleasure in engaging in activities
for their own sake, not because they satisfy physiological needs or safety needs or whatever.
And it's no coincidence that Abraham Maslow was a graduate student of Harry Harlow's.
Similarly, Donald Berlyne talked about "epistemic curiosity" -- the desire to know something,
just to know it. And Arie Kruglanski talked about individual differences in the need for
closure -- some people want to solve problems, and get answers, just for the sake of doing
so.
Sometimes, intrinsic motivation can be undermined by extrinsic motivation. In a classic study
by Mark Lepper and his associates, nursery school children were engaged in a task that's
normally enjoyable to them -- drawing on large sheets of paper with felt-tip magic markers.
Before engaging in the task, some children were promised a Good Player Award -- basically
a big gold star -- for doing so. Other children were promised no reward. And still other children
received the award unexpectedly. Because drawing on big sheets of paper with magic markers
is something that is intrinsically motivated, all the kids performed the task. But later
in a free-play condition, where there was no mention of reward, and the children had
several choices about what they could do, the children who had received the reward for
drawing spent less time drawing than those who had not been rewarded.
On the basis of these results, *** and his colleagues argued that there was a hidden
cost to reward, which was that it undermined the children's intrinsic motivation. In their
analysis, the children attributed their drawing behavior to the reward, rather than their
intrinsic desire to draw; and when the reward was removed, their desire to draw disappeared
as well.
The Lepper study is often cited as an argument against the use of rewards. But you can see
that from this graph, that the situation is actually a little bit more complicated -- because
the unexpected reward didn't undermine intrinsic motivation. If anything the children who received
the unexpected good player award spent more of their free time drawing with magic markers
even compared to the children in the control condition, who had received no reward at all.
So things are a little bit more complicated than that.
In fact, a detailed analysis by Judith Harackiewicz and her associates suggests that there's a
lot more to intrinsic motivation, than whether performance in some task is rewarded or not.
In the first place, we have to pay attention to the structure of the reward. In task-contingent
rewards, the person receives a reward simply for engaging in some activity. That's the
kind of reward there was in the Lepper study. But in performance-contingent rewards, people
are rewarded for performance that meets a certain standard. Then you have to take into
consideration the evaluative contingency: regardless of whether the award is task-contingent
or performance-contingent, does the person expect to receive the reward at the outset
of performing the task, or does he or she receive it unexpectedly afterward? Performance-contingent
rewards, by their very nature, provide feedback to the person about the nature of his performance.
If he met the standard, he gets the reward. But of course, somebody like a coach can provide
that kind of feedback without using rewards at all. And then finally there's the delivery
of the reward itself. Rewards have symbolic cue value, because they represent a certain
level of accomplishment; but they are also something tangible, something you can hold
in your hand like a trophy or spend like a dollar amount. And in addition to distinguishing
between various reward structures, we also have to distinguish between various types
of rewards. Are the rewards controlling in nature, intended mostly to get the person
to perform the task at all, or perform at a particular level? Or are the rewards informational
in nature, conveying information to the person about how well he or she has done. It turns
out it makes a big difference.
This was clearly demonstrated in a study of college students who were brought into the
laboratory to do something that was intrinsically motivating for them -- playing pinball; as
a reward, they received movie passes for achieving a meaningful but reasonable-sounding standard
of performance (scoring above the 50th or 80th percentile); and rigging the machine
to make sure that every one of the students met this standard. At the end of the experiment,
all subjects were given an opportunity to continue playing the game during some free
time, and the experimenters measured how long they continued playing.
In their first experiment, a promised reward undermined intrinsic motivation, compared
to a standard control group that got performance feedback (i.e., they saw their score) but
no evaluation and no reward condition. But a third group that was surprised with the
reward showed an enhancement of intrinsic motivation. This essentially replicates
Lepper's original experiment, but with college students rather than nursery-school pupils.
The promised reward could be perceived as controlling behavior, and probably was; and
the subjects' anticipation of external evaluation probably induced performance anxiety. On
the other hand, the unexpected reward was purely informational. The outcome suggests
that controlling rewards undermine intrinsic motivation while purely informational rewards
sustain, and may even enhance it. This is the basic under-minding effect.
In their second experiment, some subjects got the evaluation -- they were told that
they had met the standard -- but received no reward. Again, this condition was intended
to increase evaluation apprehension and performance anxiety, without the controlling element introduced
by the offer of the movie tickets (the students got the movie tickets anyway, after they had
completed their "free play" period). And again, this condition undermined intrinsic
motivation, compared to the standard control group. But again, intrinsic motivation was
enhanced for those students who were surprised with the purely informational unexpected reward
(because there was no standard set or reward promised before, it was hoped that these subjects
would not experience any evaluation apprehension or performance anxiety).
In a third experiment, again, some subjects got evaluative feedback but no reward offer;
and, again, they showed diminished intrinsic motivation compared to the standard control
group. Again, this illustrates the deleterious effects of evaluation apprehension and performance
anxiety. But in this study the third group of subjects received information about normative
performance -- they were told what the 80th percentile was -- but they got neither promise
of reward nor any hint of external evaluation (they did receive the reward, though, as a
surprise). In this condition, they maintained or enhanced intrinsic motivation. So, if
you can do it without seeming controlling, and without generating anxiety over performance
evaluation, information about performance enhances intrinsic motivation, and giving
a reward doesn't compromise it. So expected performance contingent rewards
can indeed undermined intrinsic motivation. But unexpected performance contingent rewards
can enhance intrinsic motivation.
Based on the results of an extended series of studies like these involving children and
young adults, being rewarded or not, for engaging in various kinds of tasks, have offered a
detailed process model of intrinsic motivation, the factors that can support it, those that
can enhance it, and those that can undermine it. The model first considers various contextual
and personality factors. For example, are rewards being offered for engaging in the
activity, and the rewards task-contingent, or performance-contingent? There are also
personality factors to be considered such as individual differences in level of achievement
motivation. Then you have to take into account the reason that the person has for engaging
in the task. What's the purpose of engaging in the task? Is it to develop or demonstrate
confidence? Is it to have fun, to relax, to socialize? What's the purpose? These purpose
goals establish the motivational context that influences how a person is going to approach
and experience some activity. You also have to take into consideration target
goals, which reflect the more specific idea of exactly what people are trying to accomplish
when they're performing an activity -- for example, scoring more than 20,000 points when
playing pinball. Purpose goals reflect why the person is engaging in the activity. Target
goals reflect what the individuals are trying to accomplish. Then, because performance-contingent
rewards are rewards for achieving a certain level of competence, you have to understand
how much the individual values competence in that particular domain. How involved does
he or she become in the task that's been assigned? Is he just going through the motions? Or is
there some real enjoyment or other kind of involvement? And finally there's a difference
between how competent the person is, viewed objectively, and how competent that person
perceives him- or herself to be. There can be a big difference between reality and perception.
All of these factors -- contextual factors, personality factors, purpose goals, target
goals, various motivation processes -- will combine and interact to determine the level
of a person’s intrinsic motivation to engage in any particular activity.
Motivation and reward are not particularly important for learning, but motivation and
reward do play an obvious role in behavior. But extrinsic motives are not the only determinants
of behavior: there also intrinsic motives and extrinsic motives do not always undermine
intrinsic motives. Whether reward undermines intrinsic motivation depends on what the reward
is for, how the reward is perceived, and frankly, whether the person cares. But in any case,
the two kinds motives, extrinsic motives and intrinsic motives, together determine whether
a person is going to engage in some particular activity.
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