Psychology of Learning

Module 03: Unlearned Adaptive Behaviors

Summary

Elicited Behaviors

Organisms display innate stimulus‑response connections that require no learning. These include:

• Reflexes: automatic responses like the knee‑jerk or infant rooting reflex.
• Tropisms: whole‑body forced movements, such as plants bending toward light.
• Kineses: random movements until favorable conditions are found (e.g., wood lice seeking humidity).
• Taxes: directed movements toward or away from stimuli (e.g., maggots avoiding light).
• Fixed Action Patterns: stereotyped sequences triggered by sign stimuli, such as stickleback fish attacking red bellies.
• Reaction Chains: sequences of fixed action patterns where one action triggers the next (e.g., hermit crabs changing shells). These behaviors are adaptive but inflexible, highlighting the need for learning in changing environments.

Habituation & Sensitization

These proto‑learning processes involve short‑term changes in response due to repeated stimulation:

• Habituation: decreased responding to repeated, non‑threatening stimuli (e.g., reduced startle to repeated sneezes). Neural studies in Aplysia show reduced neurotransmitter release at synapses.
• Sensitization: increased responding after intense or threatening stimuli (e.g., heightened reactivity after a shock).
• Dishabituation: recovery of a habituated response after a novel stimulus.
• Dual‑Process Theory: both habituation & sensitization occur simultaneously; behavior reflects whichever process dominates. These mechanisms help organisms allocate attention & resources efficiently, though they are shorter‑lasting than true learning.

Opponent‑Process Theory of Emotion

Richard Solomon’s theory explains how emotional experiences change with repetition:

• Emotions consist of an a‑process (initial reaction) & a b‑process (opponent aftereffect).
• The a‑process is fast, strong, & constant; the b‑process is slower, strengthens with repetition, & lasts longer.
• With repeated experiences (e.g., skydiving), fear (a‑process) diminishes while euphoria (b‑process) grows.
• Applications include drug tolerance & addiction: the pleasurable a‑process remains constant, but the unpleasant b‑process strengthens, driving tolerance & withdrawal.
• Emotions serve adaptive functions, preparing organisms for survival, while motivation—another hypothetical construct—energizes, directs, & maintains goal‑directed behavior.

Conclusion

Module 03 shows how unlearned behaviors, habituation, sensitization, & opponent‑process theory provide the foundation for understanding more complex learning. These processes illustrate how organisms adapt to stimuli & experiences, setting the stage for classical conditioning in Module 04.