Donald Olding Hebb (July 22, 1904-August 20, 1985) was a Canadian psychologist
who was influentian in the area of neuropsychology, where he sought to
understand how the function of neurons contributed to psychological processes
such as learning.
His most famous work involved the rule of covariation of synaptic weight
between two neurons, a process now known as Hebbian learning or more generally,
He spent much of his career as a lecturer of psychology at McGill University
He came up with the A/S ratio, a value that measures the brain complexity
of an organism.