Dr. Carolyn Dean, a medical doctor and naturopath, discusses neurogenesis and the historical belief that humans are born with a fixed number of neurons. This paradigm was challenged by scientists like Joseph Altman and Michael Kaplan, who found evidence of new neuron growth in adult brains. Subsequent research in various species, including humans, supports the notion that neurogenesis occurs throughout life, particularly in areas like the hippocampus.

1. Neurogenesis
Dr Carolyn Dean
is a medical doctor and naturopath. She has
authored and co-authored over 35 books
Introduction to

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Introduction to
Neurogenesis
Until relatively recently, most neuroscientists
believed that humans are born with all the
neurons they are ever going to have.
Dr. Carolyn Dean
During childhood, we may
produce new neurons to
help build ‘neural circuits’,
the pathways that serve as
information highways con-
necting different locations
of the brain. However, it was
believed that once this neural
circuit was established, add-
ing new neurons would sim-
ply disrupt the flow of infor-
mation throughout the brain,

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essentially disabling its communica-
tion system.
Scientist Joseph Altman challenged
this view in 1962, have witnessed the
birth of neurons in the hippocampus
of an adult rat. In 1979, fellow scientist
Michael Kaplan confirmed Joseph Alt-
man’s findings.
These discoveries regarding neuro-
genesis were quite controversial at
the time. However, in the 1980s, Fer-
nando Nottebohm and his team of re-
searchers established that neurons in
the brains of male canaries increased
dramatically during mating season,
enabling the birds to attract females
by learning new songs. Nottebohm
thought this concept could apply to
mammals too.
Later, Elizabeth Gould found evidence
of newborn neurons in the brains of
monkeys, with Peter Eriksson and Fred
Gage subsequently discovering that
humans produced new neurons in a
similar area of the brain.

4. the blog of
You can learn more about neural pathways in the
human body by visiting
Dr. Carolyne Dean