Perspectives on Motivation
Motivation: A process that influences the direction, persistence and vigor of goal
An instinct is an inherited predisposition to behave in a specific and predictable way
when exposed to a particular stimulus.
The concept of homeostasis, states that your body strives to maintain a state of
internal physiological equilibrium.
Your body’s internal environment is regulated by homeostatic mechanisms. Sensors
detect bodily changes and send this information to a control centre, which, in turn
regulates a response system that restores bodily equilibrium to a balanced internal
According to Hull’s Drive Theory of Motivation, physiological disruptions to
homeostasis produce drives, which are states of internal tension that motivate an
organism to behave in ways that reduce tension. (e.x. Hunger and thirst)
Hull proposed that reducing drives is the ultimate goal of motivated behavior.
Drives are seen as PUSH factors.
Whereas drives are PUSH factors, incentives are PULL factors.
An incentive is a representation of environmental stimuli that pulls an
organism towards a goal. Modern Incentive Theory emphasizes the “pull” of external stimuli and how stimuli
with high incentive value can motivate behavior, even in the absence of biological
Incentive theories of motivation have been powerfully applied to the study of
Expectancy Theories of Motivation include the value of incentives, but take a
Expectancy X Value Theory: Proposes that goal-directed behavior is jointly
determined by two factors:
1. The strength of the person’s expectation that particular behaviors will lead to
2. The value the individual places on that goal (Incentive Value).
Extrinsic Motivation Performing an activity to obtain an
external reward or avoid punishment.
Intrinsic Motivation Performing an activity for its own sake -
because you find it enjoyable or
Overjustification Hypothesis: Giving people extrinsic rewards to perform activities
that they intrinsically enjoy may “overjustify” that behavior and reduce intrinsic
Freud’s Psychodynamic Theory states that much of our behavior results from a
never-ending battle between unconscious impulses struggling for release and
psychological defences used to keep them under control.
Abraham Maslow believed that psychology’s other perspectives ignored a key
motive: our striving for personal growth.
o Deficiency Needs: Needs that are concerned with physical and social
o Growth Needs: These needs are uniquely human and motivate us to
develop our potential.
He proposed the concept of a Need Hierarchy: a progression of needs containing
deficiency needs at the bottom and growth needs at the top.
Once our basic physiological needs are satisfied, we focus on our needs for safety
and security. Once these needs are met, we turn to our growth needs until we reach
the highest level of the hierarchy.
The highest level of the need hierarchy is self-actualization, which represents
the need to fulfill our potential, and it is the ultimate human motive. Growth
Belongingness and Love Needs Needs
Self-Determination Theory: Focuses on three fundamental psychological needs:
Competence Motivation reflects a human need to
master new challenges and perfect skills.
Autonomy The need for autonomy is satisfied when
people experience their actions as a
result of free choice without outside
Relatedness Refers to our desire to form meaningful
bonds with others.
The most positive psychological outcome of all results from a balance among
all three needs.
Metabolism: is the body’s rate of energy utilization and about 2/3 of the energy we
normally use goes to support basal metabolism. Basal Metabolism: The resting, continuous metabolic work of body cells.
Short-Term Signals There are short-term hunger signals that
start meals by producing hunger and
stop food intake by producing satiety.
Long-Term Signals There are long-term signals based on
how much body fat you have. These
signals adjust appetite and metabolism
to compensate for times when you
overeat or eat too little in the short term.
Satiety: The state in which we no longer feel hungry as a result of eating.
Some of the Signals that Control Eating by Increasing or Decreasing Hunger
Signal Source Effect
Glucose Blood glucose levels Drop-Rise pattern
monitored by increases hunger.
hypothalamus and liver.
CCK (Cholecystokinin) Released into bloodstream Decreases hunger.
Leptin Secreted into bloodstream Decreases hunger.
by fat cells.
Neuropeptide Y Secreted by neuron within Increases Hunger
the PVN of the
Glucose: A key nutrient that is the body’s major source of immediately usable fuel.
Sensors in the hypothalamus and liver monitor blood glucose concentrations.
When blood glucose levels decrease, the liver responds by converting stored
nutrients back into glucose.
The drop-rise pattern caused by glucose increases hunger.
CCK (Cholecystokinin): Is a peptide that is released into the bloodstream by the
small intestine as food arrives from the stomach. It travels to the brain and
stimulates receptors in several regions that decrease eating.
Peptide: A hormone that is released by the intestines in a response to food that
helps to terminate a meal.
Leptin: A hormone that decreases appetite.
o As we gain fat, more leptin is secreted into the blood and reaches the
brain, where receptor sites on certain neurons detect it.
o These leptin signals influence neural pathways to decrease appetite
and increase energy expenditure. Brain Mechanisms
Lateral Hypothalamus (LH): An apparent “hunger on” center.
Ventromedial Hypothalamus (VMH): An apparent “hunger off” center.
Paraventricular Nucleus (PVN): A cluster of neurons packed with receptor sites for
various transmitters that stimulate or reduce appetite.
The paraventricular nucleus appears to integrate several different short-
term and long-term signals that influence metabolic and digestive processes.
One transmitter, Neuropeptide Y, is a powerful appetite stimulant.
Factors Affecting Weight and Appetite
Genetic Predisposition BMI and Adoption Study
The Concept of Set Point Size, not the number of fat cells.
Bodily Homeostasis Dietary restraints lead to disinhibition.
Anorexia Nervosa: An eating disorder involving a severe and sometimes fatal
restriction of food intake.
Bulimia Nervosa: A disorder involving the binging and purging of food, usually by
vomiting or laxative use, because of a concern with being fat.
Multiple Health Problems:
Depletion of bone mass
Death in 15% of the cases
Refusal to maintain body weight.
Intense fear of being fat despite being underweight.
15% under expected weight.
Distortions in perception of body weight.
Onset in late teens or early 20’s.
Frequent and recurrent cycles of:
o Episodes of binge eating
o Dangerous measure to prevent weight gain Binge Eating Disorder
Frequent, recurrent cycles of episodes of binge eating.
Sense of lack of control of eating.
Marked distress about binge eating.
Greater number of post-pubescent males impacted.
Causes of Eating Disorders
Genetics – higher concordance amongst identical twins.
Abnormal activity of serotonin and other chemicals that regulate eating.
Perfectionist, need for control.
Report parents disapproving with high standards.
Report more stressful events related to parents.
Depressed, anxious, with low impulse control.
Lack a stable sense of self.
Bingeing triggered by stress; followed by guilt and self-contempt.
Cultural standards of beauty as thin.
Highest prevalence in Western industrialized countries.
The components of Personality Motive Behavior:
EROS – Sexual
THANATOS – Aggressive
Mediates between ID and Superego
Sense of Right and Wrong Psychological Aspects of Hunger
Objectification Theory: Western culture teaches women to view their bodies as
objects, much as external observers would.
This increases body shame, anxiety, and this leads to eating restriction and
Good tasting food positively reinforces eating and increases food
Food variety also increases consumption.
We tend to eat more when we are dining with other people than when eating
along, in part because meals take longer.
Cultural norms influence when, how and what we eat.
The expected good taste of food motivates eating, and the thought of food can
trigger hunger. Our memory, attitudes, habits, and psychological needs affect
our food intake.
The availability, taste and variety of food powerfully regulate eating. Through
classical conditioning, neutral stimuli can acquire the capacity to trigger
Cultural norms affect our food preference and eating habits.
The heaviest known man in the world weighed 636 Kg.
The heaviest known woman in the world weighed 545 Kg.
BMI (Body Mass Index): Is a measure of the ratio of weight to height.
Heredity influences our basal metabolic rate and tendency to store energy