Learning: Simple Learning & Classical Conditioning

Unit & Assessment Updates

• Dr. Bahareh (unit coordinator)

  • Specialist in neurodiversity, autism, ADHD; open to supervising later-semester or honours projects.

  • Assessment 1 package now live on Blackboard.

  • Contains: task sheet, marking rubric, support resources, suggested 5-week timeline.

  • Recommendation: start early—5 weeks will pass quickly.

  • Communication channels

  • Email announcements already sent.

  • Use the discussion board for any content or assessment questions.

Lecture Context & Housekeeping

• Guest lecturer: Dr Rachel Patterson (learning researcher, Curtin University).

• Acknowledgement of Country: Wadjuk people of the Noongar nation; respect to Elders past & present.

Why Study Learning?

• Learning underpins all human (and animal) behaviour & emotion.

• Extends far beyond formal education settings.

  • Examples: tuning out noise, emotional responses to music, pet reactions, self-medication, joke-telling.

• Essential knowledge for aspiring psychologists (clinicians & researchers).

• Lecture series will focus on:

  • Simple learning (habituation & sensitization)

  • Classical conditioning

  • Intro reference to “also conditioning” (operant) to be covered later.

Defining Learning

• Textbook definition: “An enduring change in behaviour, or in the capacity to behave, resulting from practice or other forms of experience.”

  • Enduring – persists across time (exceptions: some simple forms fade quickly).

  • Observable in behaviour – but note complexities:

  • Learning can appear as absence of behaviour (e.g.
    not touching a hot stove).

  • Performance ≠ learning – may require maturation (small child can’t make sandwich) or motivation (vacuuming only when pocket-money offered).

  • Experience-dependent – must stem from environmental interaction; excludes innate physiological changes (e.g.
    sweating when hot, yawning when tired).

Simple Learning: Habituation & Sensitization

• Occurs with a single, repeatedly presented stimulus.

• Behaviour change usually temporary (not “enduring” in the long-term sense).

Habituation

• Definition: Decrease in strength of an elicited response after repeated presentations of the same stimulus.

• Typically observed in reflexes:

  • Startle reflex (jump, blink, heart-rate spike).

  • Orienting reflex (automatic attention shift to novel event).

• Everyday instances

  • Ignoring train noise when living near tracks.

  • Olfactory adaptation to constant smells.

  • Visual familiarity with stable surroundings.

• Adaptive value: frees limited attentional resources; prevents sensory overload.

• Must be distinguished from fatigue—motor capacity remains intact (illustrated by renewed response to tray of smashing glasses after balloon habituation).

Sensitization

• Definition: Increase in response strength with repeated presentations.

• More likely when stimulus is:

  • Intense (gunshot, car backfire).

  • Evolutionarily relevant to danger (snake hiss, sudden loud noise).

  • Encountered while organism’s arousal is already high (nervous before birthday speech ⇒ balloons become more startling).

• Adaptive value: maintains vigilance toward potential threats.

Classical Conditioning: Historical Foundations

• Discovered by Russian physiologist Ivan Pavlov (late 1800s).

  • Initially studied digestive reflexes in dogs.

  • Noticed dogs salivated to researcher footsteps/lab coats ⇒ pursued phenomenon.

  • Standard apparatus:

  • Dog harnessed; food delivered through hatch.

  • Saliva collected via oral cannula into graduated tube.

  • Pavlov reportedly ensured humane treatment of dogs.

Classical Conditioning: Core Terminology

• Unconditioned Stimulus (UCS) – naturally elicits response (food).

• Unconditioned Response (UCR) – innate response to UCS (salivation to food).

• Conditioned Stimulus (CS) – originally neutral; elicits response after pairing (metronome).

• Conditioned Response (CR) – learned response to CS (salivation to metronome).

• Decision tree for identifying terms:

  1. Is it a thing (stimulus) or a reaction (response)?

  2. Does it occur naturally or is it conditional on learning?

Illustrative Conditioning Examples

• Food poisoning (Olivia & prawns)

  • UCS – contaminated bacteria.

  • UCR – nausea/sickness.

  • CS – prawns.

  • CR – nausea/sickness in response to prawns.

• Dog & leash (Claire & puppy Maple)

  • UCS – trip to the park (fun environment).

  • UCR – happiness/excitement.

  • CS – leash being taken from cupboard.

  • CR – jumping/excitement at sight of leash.

Processes in Classical Conditioning

• Acquisition

  • Gradual strengthening of CR as UCS–CS pairings accumulate.

  • Often requires multiple trials unless UCS is extremely strong/aversive.

  • Graphically: ascending curve that plateaus.

• Extinction

  • CS presented without UCS ⇒ CR weakens.

  • Pavlov: repeated metronome‐only trials ⇒ saliva drops to baseline.

• Spontaneous Recovery

  • Reappearance of CR after time gap (e.g.
    $24\text{ h}$ rest).

  • Demonstrates extinction forms new inhibitory learning; original acquisition memory remains.

  • Recovery magnitude diminishes with repeated extinction-rest cycles, but acquisition trace never fully erased.

• Generalization

  • Stimuli resembling CS evoke CR.

  • Gradient: similarity ↑ ⇒ response strength ↑.

  • Example graph: $4000 \text{ Hz}$ tone (CS) elicits max saliva; $3500 \text{ Hz}$ evokes moderate; distant frequencies evoke little.

• Discrimination

  • Opposite of generalization; organism learns to respond only to specific CS.

  • Can be shaped: $1000\text{ Hz}$ tone followed by food, $800\text{ Hz}$ never followed ⇒ salivation to $1000\text{ Hz}$ only.

Factors Influencing Conditioning Strength

• Timing (Temporal Contiguity)

  • Best when CS precedes UCS and delay is short.

  • Exception: Taste-aversion learning – strong even with hours-long CS→UCS gap (adaptive, life-preserving).

• Predictability (Contingency)

  • CS must provide reliable information about UCS occurrence.

  • If UCS appears equally often without CS, association fails.

• Novelty (Latent Inhibition)

  • Familiar stimuli become poorer CSs because of prior nonreinforced exposure.

• Salience (Noticeability but not Overpowering)

  • CS must be detectable; too faint ⇒ unnoticed, too intense ⇒ distracts/overwhelms (fire alarm masking food pairing).

Applications: Conditioning of Emotions

• Many human affective states (fear, disgust, sexual arousal, preferences) arise via classical conditioning.

The Little Albert Experiment (Watson & Rayner, 1920)

• Goal: demonstrate acquisition of learned fear.

• Participant: anonymous infant ≈ 9 mo (nicknamed “Albert”).

• Baseline testing: no fear toward white rat, rabbit, dog, monkey, cotton wool, burning newspaper; strong fear to loud noise (hammer striking steel bar).

• Conditioning (at ≈ 11 mo):

  • Procedure: present rat → as Albert touches it, strike hammer on steel bar.

  • Multiple pairings over several days.

  • Outcome: rat alone evokes crying, body withdrawal (CR = fear).

• Generalization: fear extended to rabbit, dog, fur coat, cotton wool, and Watson in a Santa mask.

• Ethical concerns

  • No informed consent standards in 1920.

  • Fear not fully extinguished—family moved away.

  • Modern ethics would prohibit such procedure.

• Follow-up lore: suspected adult “Albert” reportedly led normal life but disliked animals; identity not definitively confirmed.

Ethical, Philosophical & Practical Implications

• Animal welfare in research (Pavlov) vs.
  human participant rights (Little Albert).

• Clinical relevance

  • Understanding conditioning informs exposure therapy for phobias (extinction principles).

  • Habituation models guide sensory integration work in neurodiversity.

• Everyday application

  • Advertising leverages emotional conditioning (pairing products with positive UCS like upbeat music or celebrities).

  • Habit formation & breaking rely on CS–UCS contingencies (e.g.
    coffee smell → alertness expectations).

Key Numerical & Technical References

• Frequency generalization example: $4000\text{ Hz}$ CS; neighboring $3500\text{ Hz}$ ≈ moderate CR; distant tones minimal.

• Discrimination training example: $1000\text{ Hz}$ vs.
  $800\text{ Hz}$.

• Spontaneous recovery gap: $24\text{ h}$ rest period in Pavlov’s schedule.

• Little Albert’s age milestones: baseline at $9\text{ mo}$; conditioning at $11\text{ mo}$.

Study Roadmap / Connections to Upcoming Content

• Current lecture covers simple learning & classical conditioning.

• Next lectures will likely tackle operant (instrumental) conditioning and observational learning, building on concepts of stimulus–response association and reinforcement.

• Revisit extinction, generalization & discrimination when discussing therapeutic interventions and behaviour modification strategies.