Which intelligence theorist has shown that average intelligence scores have steadily increased in the united states over the last century?

The Flynn effect is entitled for james flynn who prepared much to document it and endorse awareness of its implication. The duration the aforementioned was invented by richard herrnstein and charles murray novelists of the bell curve. Although the over-all word for the phenomenon discussing to no researcher in specific endures to be earthly growth in IQ scores. The Flynn effect bring up to the detail that in the united states and other western developed nations, average intelligence scores have improved steadily over the past century proposed explanations involve many environmental factors such as better nutrition and more education and it is the substantial and long-sustained increase in both fluid and crystallized intelligence test scores dignified in many parts of the world from coarsely 1930 to the existent day.