Fifty Classic Studies in Psychology
Last revised 9/30/2026

Fifty Classic Studies in Psychology

How psychology knows what it knows, one landmark experiment at a time

This collection covers the landmark studies behind modern psychology, from Ebbinghaus memorising nonsense syllables in the 1880s to the 2015 project that re-ran a hundred published experiments. We have chosen fifty studies and arranged them by the method each one used, so every session shows what the researchers actually did, what they found, and how well the result has held up. Each study is told from its set-up to its numbers in plain language, with no statistics required. You finish able to ask of any psychological claim the question that matters most: how would they know that?

AnthologyField Guide
Earn6CreditsinPsychology
9Modules50Sessions507Cards149Quizzes

Modules in this Collection’s System

The laboratory experiment

Change one thing, hold everything else still, and watch what follows.

6Sessions

Timing the mind

Clever tasks that measure what attention and memory do in milliseconds and minutes.

6Sessions

Animals as models

What dogs, rats and pigeons revealed about learning, and where the animal model stops.

6Sessions

Infants and children

How researchers put questions to people who cannot yet answer in words.

6Sessions

Field experiments

Studies run in summer camps, hospitals, subway cars, schools and care homes.

6Sessions

Single cases

Individual patients whose injuries revealed how the brain divides its work.

5Sessions

Twins, adoptees and lifelong studies

Designs that pull genes apart from upbringing and follow people for decades.

5Sessions

Decision experiments

Simple choice problems that exposed systematic departures from rational judgement.

5Sessions

The replication reckoning

Famous results re-examined, and what psychology changed as a result.

5Sessions

What You'll Walk Away With

  • 5study-reading questions for judging any psychological claim you meet in the news.
  • 8research designs you can recognise and weigh by what each can and cannot prove.
  • 4warning signs that a famous finding may not survive replication.
  • 3ethical principles that now govern research with people and animals.

You'll Have Answers To

  • ?Why did two thirds of Milgram's volunteers keep pressing the switch, and when did they stop?
  • ?How can you test what a baby knows before it can say a single word?
  • ?What does it really mean that a trait is 70% heritable?
  • ?Why did some of psychology's most famous findings fall apart when others tried again?
  • ?Can people tell you the real reasons behind their own choices?

Critical Concepts Explored

controlled comparisonconfederate and cover storydemand characteristicsfield experimentsingle-case dissociationheritabilitylongitudinal cohortframing effectreplication crisispreregistration
Editor's Note
“Fifty famous experiments, told honestly, including the ones that did not survive.”

Grouping the studies by method rather than topic is the collection's quiet strength: readers learn to see what each design can prove. Every study starts with what was actually done, and the closing module on failed replications turns the classics into a lesson in weighing evidence.

Editor's Brief
Who it's for
Curious readers who want to see how psychology's best-known findings were actually produced and tested.
What stands out
It selects fifty landmark studies, groups them by method, and tells each one plainly from set-up to replication record.
Read if
Read it if you want to judge a psychology headline by asking how the researchers could know.
Gold Quotes
The design of a study decides what its result can mean, which is why method matters more than the headline.

A lab experiment can show cause but may not travel beyond the lab; a single patient can overturn a theory but cannot give an average. Knowing which design produced a claim tells you how far to trust it.

About the Curator
PPsychology Digest

Psychology Digest publishes collections on the human mind: why we think, feel, remember and behave the way we do. Grounded in real science, each one helps readers understand themselves and others, and put that understanding to work in their relationships, choices and everyday lives.

Fifty Classic Studies in Psychology | LearningFirst