Five separate pulses of serotonin, designed to simulate five shocks to the tail, strengthened the synaptic connection for days and led to the growth … - Eric Kandel

Even though I had long been taught that the genes of the brain are the governors of behavior, the absolute masters of our fate, our work showed that, in the brain as in bacteria, genes are also servants of the environment. ...An environmental stimulus... activates modulatory interneurons that release serotonin. The serotonin acts on the sensory neuron to increase cyclic AMP and to cause protein kinase A and MAP kinase to move to the nucleus and activate CREB. The activation of CREB, in turn, leads to the expression of genes that changes the function and the structure of the cell.

I was very much influenced by the psychology of Freud and by early workers in the field of learning and memory—James, Thorndike, Pavlov, Skinner, and Ulric Neisser. Their thinking, and even their errors, provided a wonderfully rich cultural background for my later work.

In Vienna, Modernism had three main characteristics. The first was the new view of the human mind as being largely irrational by nature. ...they questioned what constitutes reality, what lies below the surface appearances of people, objects, and events. ...They discovered that ...people harbor not only unconscious erotic feelings, but also unconscious aggressive impulses that are directed against themselves as well as against others. Freud later called these dark impulses the death instinct.