1900: Many people suffer from the stresses the industrial, urbanizing society, experiencing a variety of nervous disorders, such as insomnia, headaches, anxiety, and exhaustion. Some doctors think this is a disease they call "neurasthenia," and there are many patent medicines claiming to be cures. Some think that you are born with a temperament toward this condition, as are those who succumb to serious mental illness and are confined to asylums for the insane. A few doctors begin to look for a way to treat the mind, rather than the body, to cure these conditions.

Here are a few steps on the science odyssey from then to now, including links to activities and databank entries on this site.

• At the end of the nineteenth century, female patients with odd behaviors were often described as suffering from hysteria. Dr. Charcot studied hysteria in his asylum in Paris, attracting such prominent students as Sigmund Freud.
  

  People: Jean-Martin Charcot
  

• By 1900, Sigmund Freud has begun to elaborate an explanation and a therapy for hysteria.
  

  "That's My Theory!" with special guest Sigmund Freud
  Discoveries: Freud's book, "The Interpretation of Dreams" released
  People: Sigmund Freud
  

• In 1905, Alfred Binet studies the ability of children to perform tasks, introducing a method to test "intelligence."
  

  Discoveries: Binet pioneers intelligence testing
  

• In 1913, building on the recent work of Pavlov, John Watson presents his theory that human behavior is based upon conditioned responses to stimuli.
  

  Discoveries: Watson launches behaviorist school of psychology
  People: Ivan Pavlov
  People: John Watson
  

• In spite of the growth of behaviorism, in the early 1920s, the Eugenics movement, based on the idea that human behavior is an inherited trait, reaches its height.
  

  Discoveries: Eugenics movement reaches its height
  People: Charles Davenport
  

• During the 1930s, scientists begin to try to affect the workings of the brain to treat mental illness, sometimes using radical techniques.
  

  Discoveries: Moniz develops lobotomy for mental illness
  Discoveries: Electroshock therapy introduced
  

• From the late 1930s through the 1960s, B.F. Skinner contributes to the field of behaviorist psychology.
  

  People: B.F. Skinner
  

• During approximately the same period, Jean Piaget expands our understanding of how children's mental abilities develop.
  

  Discoveries: Piaget describes stages of cognitive development
  

• Meanwhile, Harry Harlow conducts experiments on monkeys and finds that love may be as important as nourishment in an infant's emotional development.
  

  People: Harry Harlow
  

• In 1952, Henri Laborit finds a tranquilizer that appears to relieve the symptoms of those suffering from mental illness, ushering in a new era of drug therapies for behavior disorders.
  

  On The Edge: Miracle Pill
  Discoveries: Drug for treating schizophrenia identified
  

• In the 1950s and 1960s, Wilder Penfield publishes studies of the human brain, which isolate specific areas of the brain that control motor impulses, sensory inputs, and memories.
  

  You Try It: Probe the Brain
  People: Wilder Penfield
  

• In the early 1960s, Roger Sperry refines our understanding of brain function, experimenting with patients whose right and left hemispheres have been severed.
  

  People: Roger Sperry
  

• At the same time, the ideas of earlier psychologists such as Freud and Harlow evolve into new psychotherapies developed by their students.
  

  People: Frieda Fromm-Reichmann
  People: Abraham Maslow
  

As we approach the later years of the century, new technologies and new understandings of genetics and biochemistry gradually point scientists away from behaviorist and psychotherapeutic approaches for understanding human behavior.
• In the 1970s and 1980, new scanning devices allow detailed mapping of brain functions.
  

  Discoveries: CT scan and MRI introduced
  

• The discovery of brain chemicals such as endorphins leads to an understanding, in 1975, of how behavior is a biochemical event.
  

  Discoveries: Role of endorphins discovered
  

• This leads to more effective drugs that can alter one's behavior or mood. The most prominent of these by the 1990s is Prozac.
  

  Discoveries: Antidepressant Prozac introduced
  

• Genetic research in the 1990s leads to identification of certain genes that seem tied to behaviors.
  

  Discoveries: Search for behavioral genes
  

Today: Science has come to understand that our mental condition is part of a complex interplay between our biology and our environment. We have identified brain structures and chemistry which control behavior and have produced medicines which affect our behavior. We have begun to identify the genes that control the molecules of the brain. We also have a range of psychological tools to help us cope with the stresses of life as we enter the twenty-first century. Our challenge is to gain a greater understanding of how the environment actually affects our genes, creating the diversity of human behavior.