The Method

«Overview of Reflex Contributions   /   Section 4»

In the middle 1800s it was believed that various types of behavior and action were the result of specific areas in the brain. This notion gained broad support following the findings of Paul Broca and then Carl Wernicke. During this same time, John Hughlings Jackson proposed that the organization of the brain was in fact a phylogenetic hierarchical organization in which the newest areas of the brain managed the most complex behaviors, the middle older areas of the brain managed basic life-sustaining behaviors, and the oldest and lowest areas of the brain managed activities vital to ongoing survival. Jackson went on to propose that “when the brain is functioning as it should, higher (phylogenetically newer) neural circuits inhibit lower (phylogenetically older) neural circuits; but when the higher neural circuits are rendered functionless (due to congenital differences, disease or trauma) the lower neural circuits rise in activity.” (Selected writings of John Hughlings Jackson, Basic Books, 1958, Reprint from Medical Press and Circular, 1887) While Jackson was highly regarded for his work in epilepsy and aphasia, his theories of functional organization and dissolution were given little attention during his lifetime. Sigmund Freud, known for his theories of psychoanalysis and dream states, was among the first to directly build on Jackson’s theories of functional organization and dissolution. This was at a time, however, when the fields of psychology and neurophysiology were separate areas of study. It wasn’t until the mid-1900s – over fifty years after Jackson’s death – that his theories were embraced and built upon by neurologists.

The noted Russian physiologist, Alexander Luria, wrote that “the complexity of John Hughling Jackson’s thinking was beyond the comprehension of his contemporaries Jackson’s thought was particularly modern – so much so, in fact, that his ideas are receiving more serious consideration today than they did in his own time." (44, p. 24). While Broca, Wernicke and others were correct in assuming that localized brain structures are important to specific functions, they were not correct in assuming that function was not in some way coordinated among all structures. Luria’s work demonstrated that complex behavioral processes involve a number of brain structures, each playing highly specific roles (as Wernicke and Broca had clearly determined) and all contributing to a form of coordinated control (as Jackson had proposed). Luria referred to this as functional organization of the brain. Luria’s work with brain damaged soldiers further demonstrated that blocked and damaged neural pathways could be activated or restored when normal function had been lost. Luria’s work helped to prove first that motor programs, whether innate or learned (as proposed by Nikolai Bernstein), remain in the body’s memory even if blocked or damaged neural pathways do not allow their function; and second, that neural pathways can be unblocked when inhibited and re-forged because of the functional organization that exists in the brain.

Below are more in depth summaries of the contributions made by: