Chapter 11; What Drives Us: Hunger, Sex, Belonging, and Achievement

  1. Basic Motivational Concepts
    1. Motivation
      1. A need or desire that energizes and directs behavior
      2. Arise from the interplay between nature (the bodily “push”) and nurture (the “pulls” from our personal experiences, thoughts, and culture)
      3. Four perspectives for understanding motivated behaviors:
        1. Instinct theory: focuses on genetically predisposed behaviors
        2. Drive-reduction theory: focuses on how we respond to inner pushes and external pulls
        3. Arousal theory: focus on finding the right level of stimulation
        4. Abraham Maslow’s hierarchy of needs: focuses on the priority of some needs over others
    2. Instincts and Evolutionary Theory
      1. Instinct
        1. A complex behavior that is rigidly patterned throughout a species and is unlearned
        2. Examples
          1. Imprinting
          2. Infants innate reflex to suck nipple
          3. Infants grasping behavior
      2. Evolutionary Psychology
        1. Genes do predispose some species-typical behavior
    3. Drives and Incentives
      1. Physiological needs
        1. A basic bodily requirement
        2. Example
          1. Food and water
      2. Drive-reduction theory
        1. The idea that a physiological need creates an aroused state (a drive) that motivates an organism to satisfy the need
      3. Homeostasis
        1. A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level
      4. Need to drive to drive-reducing behaviors
      5. Incentive
        1. A positive or negative environmental stimulus that motivates behavior
    4. Arousal Theory
      1. Some motivated behaviors actually increase rather than decrease arousal
      2. Sensation-seekers
        1. Risk takers
        2. May also be motivated to master their emotions
      3. Yerkes-Dodson law
        1. The principle that performance increases with arousal only up to a point, beyond which performance decreases
        2. Moderate arousal leads to optimal performance
        3. When taking an exam, it pays to be moderately aroused- alert but not trembling with nervousness
    5. A Hierarchy of Needs
      1. Hierarchy of needs
        1. Maslow’s pyramid of human needs, beginning at the base with physiological needs that must first be satisfied before people can fulfill their higher-level safety needs and then psychological needs
      2. Some needs take priority
      3. Bottom to top
        1. Physiological needs
          1. Satisfy hunger and thirst
        2. Safety needs
          1. Need to feel safe and secure and stable
        3. Belongingness and love needs
          1. Need to love and be loved
        4. Esteem needs
          1. Need for self-esteem, achievement, competence, and independence
        5. Self-actualization needs
          1. Need to live up to our fullest and unique potential
        6. Self-transcendence needs
          1. Need to find meaning and identity beyond the self
    6. The Physiology of Hunger
      1. What physiological factors produce hunger?
        1. A. L. Washburn conducted an experiment where he swallowed a balloon attached to recording device
          1. When inflated to fill his stomach, the balloon transmitted his stomach contractions
          2. Washburn supplied information about his feelings of hunger by pressing a key each time he felt a hunger pang
          3. The discovery: whenever washburn felt hungry, he was indeed having a stomach contraction
      2. Body Chemistry and the Brain
        1. Glucose
          1. The form of sugar that circulates in the blood and provides the major source of energy for body tissues. When its level is low, we feel hunger.
        2. Set point
          1. The point at which the “weight thermostat” may be set. When the body falls below this weight, increased hunger and a lowered metabolic rate may combine to restore lost weight.
        3. Basal metabolic rate
          1. The body’s resting rate of energy output
        4. Appetite Hormones
          1. Increases appetite

Ghrelin: hormone secreted by empty stomach; sends “I’m hungry” signals to the brain

Orexin: Hunger-triggering hormone secreted by hypothalamus

          1. Decreases appetite

Leptin: protein hormone secreted by fat cells; when abundant, causes brain to increase metabolism and decrease hunger

PYY: digestive tract hormones; sends “I’m not hungry” signals to the brain

    1. Sexual Orientation
      1. Sexual orientation
        1. The direction of our sexual attractions, as reflected in our longings and fantasies
      2. Origins of Sexual Orientation
        1. Same-sex attraction in other species
        2. Brain differences
        3. Prenatal influences