Motivation, Hunger, and Emotion – Key Vocabulary

Motivation: Definitions & Characteristics

• Definition of Motivation

  • Refers to the forces acting on/within an organism that initiate and direct behaviour ⇒ the “why” behind actions.

  • Includes both internal (biological, emotional, cognitive) and external (social, environmental) forces.

  • Two processes:

  • Initiation – starting a behaviour.

  • Direction – guiding behaviour toward a goal.

• Four Sources of Motivation

  • Biological, emotional, cognitive, social.

• Three Core Characteristics

  • Activation – beginning/producing behaviour.

  • Persistence – continued effort, determination.

  • Intensity – vigour, focused attention and effort.

Classic Theories of Motivation

• Serve as foundational “building blocks.”

(1) Instinct Theories – Inborn Behaviours as Motivators

• Proponents: William McDougall, William James (influenced by Darwin).

• Behaviour is innate, unlearned, evolutionarily programmed.

• Major criticism: Primarily descriptive; fails to explain underlying mechanisms.

• Legacy: Sparks modern evolutionary psychology.

• James’s List of Human Instincts (partial):

  • Attachment, Fear, Greediness, Disgust, Hunting, Rivalry, Play, Shyness, Shame, Resentment, Anger, Curiosity, Bashfulness, Modesty, Secretiveness, Cleanliness, Sociability, Love, Parental Love.

(2) Drive Theories – Biological Needs as Motivators

• Replaced instinct account.

• Core idea: Behaviour motivated by desire to reduce internal tension from unmet biological needs.

• Key terms:

  • Drive – internal state pushing organism to act (e.g., thirst).

  • Homeostasis – body’s tendency toward balanced internal state.

• Sequence: \text{Need} \rightarrow \text{Drive} \rightarrow \text{Behaviour} \rightarrow \text{Drive Reduction}.

(3) Incentive Theories – Goal Objects as Motivators

• Core idea: Behaviour “pulled” by external goals (rewards, money, recognition).

• Grounded in classical & operant conditioning.

• Combination with drives explains broad range (e.g., hunger + delicious food).

(4) Arousal Theory – Optimal Stimulation as Motivator

• People seek to maintain optimal arousal, neither too high nor too low.

  • Low arousal → boredom → seek stimulation.

  • High arousal → stress → seek calm.

• Yerkes–Dodson Law: \text{Performance} = f(\text{Arousal}); best at moderate arousal, optimum varies by task & individual.

• Sensation Seeking

  • Trait reflecting preference for high sensory/physical arousal.

  • Examples: skydiving, extreme sports, travel.

Humanistic Theories – Human Potential as Motivator

• Proponents: Carl Rogers, Abraham Maslow.

• Emphasise psychological & cognitive factors; drive toward self-fulfilment.

• Maslow’s Hierarchy of Needs (bottom → top):

  1. Physiological (food, water, sleep)

  2. Safety (security, shelter)

  3. Belongingness & Love (relationships, affection)

  4. Esteem (achievement, respect)

  5. Self-Actualisation (realising personal potential)

• Need to Belong

  • Fundamental drive to form enduring, caring relationships.

  • Social bonds enhance health & resilience; isolation/ostracism causes distress & physical pain.

Contemporary Theories of Motivation

Self-Determination Theory (SDT) – Deci & Ryan

• Optimal functioning when 3 innate psychological needs met:

  1. Autonomy – sense of volitional control.

  2. Competence – feeling effective/capable.

  3. Relatedness – meaningful connections.

• Intrinsic Motivation – activity for inherent satisfaction.

• Extrinsic Motivation – activity for reward/avoid punishment.

Achievement Goal Theory

• Achievement Motivation – desire to excel/outperform.

• Goal Orientations

  • Mastery Goals (growth mindset): focus on learning & improvement.

  • Performance Goals (fixed mindset): focus on demonstrating competence vs. others.

• Cultural Differences

  • Individualistic: personal success.

  • Collectivistic: group honour, social contribution.

Hunger & Eating – A Biological and Psychological Drive

Multifactorial Nature

• Hunger = biological motive; eating behaviour shaped by biological, social, psychological factors.

Energy Homeostasis

• Key variables:

  • Glucose – primary fuel.

  • Insulin – regulates glucose & weight.

  • Basal Metabolic Rate \text{BMR} – energy used at rest.

  • Body Fat – stored excess energy.

  • Baseline Body Weight – weight maintained by homeostasis.

  • Formula: \text{Calories Consumed} = \text{Calories Expended} (balance).

Short-Term Hunger Signals

• Blood glucose drop precedes eating.

• Insulin rise ~30 min pre-meal.

• Ghrelin (stomach hormone) ↑ before meals, ↓ after.

• Body T ↑, metabolism ↓ can intensify hunger.

Learning & Conditioning

• Classical conditioning: time of day, sight/smell food → insulin/ghrelin shifts.

• Operant conditioning: taste preferences (sweet, salty, fatty) reinforced by positive incentive value; situational eating habits learned.

Satiation – Why We Stop Eating

• Stretch receptors (stomach) send fullness info.

• Cholecystokinin (CCK) slows stomach emptying.

• Sensory-Specific Satiety – decreased desire for a particular food while still hungry for others (dessert phenomenon).

Long-Term Weight Regulation Signals

• Leptin – from fat cells; conveys fat stores, influences hunger & metabolism.

• Insulin – long-term energy balance.

• Neuropeptide Y (NPY) – hypothalamic neurotransmitter; stimulates appetite, reduces energy expenditure.

Body-Weight Theories

• Set-Point Theory – body defends natural weight W_{set}.

• Thrifty Gene Hypothesis – genes favour efficient fat storage; adaptive in scarcity, risk for obesity in abundance.

Weight-Related Stigma & Health

• Rising global weight & reduced activity ⇒ stigma/“weight shaming”.

• Stigma causes stress, avoidance (gyms, doctors), can promote weight gain.

• Shift to behaviour-focused health: healthy behaviours lower mortality across BMI categories.

Emotion & Emotional Expression

Emotion – Introduction & Components

• Emotions = complex psychological states crucial for survival, decision-making, social interaction.

• Components:

  1. Cognitive – subjective feeling.

  2. Physiological – bodily arousal.

  3. Behavioural – outward expression (facial, vocal).

• Functions: interpret survival-relevant info; communicate internal states.

Moods vs. Emotions

• Moods: longer (hours/days), milder, diffuse cause, easier to regulate, no consistent expression.

• Emotions: shorter, intense, specific cause, object-directed, harder to regulate, universal expressions.

Evolutionary Perspective

• Darwin: emotions evolved for survival & social signalling.

• Adaptive roles: Fear → escape; Anger → defend; Disgust → avoid toxins; Love → bonding.

Basic Emotions

• Biologically innate, universal, hard-wired; people can experience mixed emotions simultaneously.

Expression of Emotion

• Facial expressions primary channel; also body language, gestures, tone.

• Universality Evidence

  • Darwin (1872) hypothesis; Ekman’s cross-cultural studies (>7,000 expressions).

  • Spontaneous expressions in blind vs. sighted children similar.

• Duchenne vs. Non-Duchenne Smiles – “true” smile involves eye-muscle activation.

Dimensions, Culture, Gender

• James Russell’s core dimensions: Pleasant–Unpleasant, Activation–Deactivation.

• Some cultures emphasise interpersonal engagement.

• Display Rules regulate expression timing/intensity.

• Gender: similar frequency/experience, but expression shaped by norms (e.g., anger, sadness).

Neuroscience of Emotion

Sympathetic Nervous System (SNS)

• Emotions provoke SNS “fight-or-flight.”

• Different emotions → distinct SNS patterns:

  • Fear: skin temperature ↓ (“cold feet”).

  • Anger: skin temperature ↑ (“hot under the collar”).

• Patterns appear universal.

Lie Detection

• Polygraph measures HR, respiration, skin conductance; assumes lying = anxiety.

• Issues: no unique “lie” pattern, some lie calmly, innocents anxious, subjective interpretation.

• Micro-expressions – fleeting facial cues revealing concealed emotion.

The Emotional Brain – Amygdala

• Part of limbic system; processes especially fear.

• Functions: threat evaluation, emotional response, hormonal triggers.

• Evidence:

  • Amygdala-lesioned rats fail to acquire conditioned fear.

  • Humans with damage show “psychic blindness” to fear cues.

LeDoux’s Dual Pathways

• High Road: Thalamus → Cortex → Amygdala (slower, cognitive appraisal).

• Low Road: Thalamus → Amygdala (fast, automatic). Enables rapid SNS activation.

Emotion Regulation & Brain Mechanisms

• Essential for well-being, relationships, coping.

• Develops from caregiver interactions; later uses reappraisal to reframe events.

Prefrontal Regions

• Ventromedial PFC – regulates amygdala, inhibits responses, supports decision & self-control.

• Orbitofrontal PFC – integrates reward info for decisions.

• Dorsolateral PFC – executive functions, social cognition, helps regulate social behaviour.

Theories of Emotion

James-Lange Theory

• Stimulus → Physiological/Behavioural Changes → Emotion.

• Facial feedback studies offer support.

• Cannon’s Critiques: similar body reactions for different emotions; emotional experience can precede visceral changes; inducing physiology doesn’t always yield emotion.

Two-Factor Theory (Schachter & Singer)

• Emotion = Physiological Arousal + Cognitive Label.

• Sequence: Stimulus → Arousal → Interpretation → Emotion.

• Excitation transfer – arousal can spill over.

• Criticised: arousal not always necessary, label not sole path.

Cognitive Appraisal Theory (Lazarus, Arnold)

• Stimulus → Cognitive Appraisal → Emotion → Physiology/Behaviour.

• Appraisal of personal significance triggers emotion.

• Critics: Some emotions rapid/automatic; modern view recognises multiple trigger pathways.

Ethical, Philosophical & Practical Implications

• Weight Stigma – moral obligation to combat harmful health effects; shift to behaviour-based health view.

• Emotion Regulation – critical for mental health interventions; emphasises early caregiving and cognitive reframing techniques.

• Lie Detection – ethical caution in legal/occupational contexts given unreliability.

• Cultural Display Rules – importance of cultural competence in globalised interactions.

Numerical & Statistical Notes

• Ekman identified >7,000 facial expressions.

• SNS body-mapping (Nummenmaa et al., 2014) visualises 9 emotions (Anger, Fear, Disgust, Happiness, Sadness, Surprise, Love, Depression, Neutral).

Connections & Recap

• Motivation and emotion processes share reliance on arousal and cognitive interpretation.

• Brain circuitry (PFC–Amygdala) underpins both motivation (goal pursuit) and emotion regulation.

• Homeostasis parallels: body energy balance vs. emotional equilibrium via regulation.

• Evolutionary roots integrate instinct theories, basic emotions, and thrifty gene hypothesis.

(Contact: Yang Yang, PhD student – yyang3077@gatech.edu)