PSYC2 LECTURE 9 MOTIVATION:THEORIES & HUNGER

Reminders & Course Business
ž Silence

your cell phones ž Exam 1 Results posted later today
ž 24 hour waiting period before you

contact TA!

2

Mean = 34.9

1 SD (+/- 6.1) 2 SD

Lecture 9 Objectives
ž Why

do we do what we do? ž Major theories of motivation
— BIS/BAS — Expectancy X Value — Maslow’s Hierarchy of Needs

ž How

do we explain hunger and eating?

— Biologically? — Psychologically?

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What is motivation?
Motivation: a process that influences the direction, persistence, and vigor of goaldirected behavior

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WHY do we do things?

Instincts: No Longer the Explanation
— Darwin’s theory of

evolution

— Instinct: a strong,

biological characteristic that automatically produces a particular response when the organism is exposed to a particular stimulus

— Circular reasoning
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A More Modern Approach
Homeostasis:
internal physiological equilibrium

Requires:
○ A sensory

mechanism ○ A response system ○ A control center
— Set point: fixed level

that maintains homeostasis
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Homeostatic Disequilibrium

ž Imbalance

leads to drives (Hull, 1943)

ž Drives:

internal ‘tensions’ that motivate an organism
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Homeostatic Disequilibrium
BUT we often behave in ways that increase rather than reduce arousal

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Major Psychological Theories
We Will Talk About
1. Approach/Avoidance (BIS/BAS) 2. Cognitive Processes 3. Maslow’s Hierarchy of Needs

Read on your own
1. Psychodynamic views 2. Self-determination theory

Approach Vs. Avoidance (Gray, 1991)
ž Behavioral Activation

System (BAS): produces movement toward positive goals in anticipation of pleasure Inhibition System (BIS): produces fear and escape/avoidant behaviors

ž Behavioral

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WANT

DO NOT WANT

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Cognitive Process Views
Expectancy x value theory: behavior is motivated by
○ Strength of the expectation that behavior will lead

to a goal ○ Incentive value that person places on goal
— Incentives are stimuli in environment that pull for

behavior

Motivation

Expectancy (can you get it?)

Incentive Value (do you want it?)
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Cognitive Process Views
ž Extrinsic

motivation: performing an activity to obtain an external reward or to avoid punishment motivation: performing an activity for its own sake

ž Intrinsic

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Maslow’s (1954) Hierarchy of Needs

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Hunger and Weight Regulation
Physiological

Psychological
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Hunger and Weight Regulation
ž Metabolism:

the body’s rate of energy (caloric) utilization state in which we no longer feel hungry

ž Satiety:

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Hunger Regulation
Hunger is not necessarily linked to immediate energy needs
ž

Information on energy supply interacts with other factors (amount, variety) Homeostatic mechanisms are designed to prevent us from running low on energy Set point for energy level, weight (fat mass)

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