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Wayne L. Klein, PhD

Neuropsychological Assessment of Children & Adults; Couples & Individual Psychotherapy Offices in Franklin, MA & Spaulding Center for Children, Sandwich, MA
About Dr. Klein
Children and Adolescents
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Autism, Asperger's & PDD
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Animal Intelligence
Brain Evolution
How the Mind/Brain Works
Human Evolution
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Brain Evolution



Human evolution is a long history of the overcoming of barriers. The first barrier was the need for a universe, for space and matter. This occurred 14 billion years ago with the Big Bang. After hundreds of millions of years, the hot plasma of subatomic particles cooled sufficiently for atoms to form. But the only chemical elements were hydrogen and helium. It would take nuclear fusion in massive stars to produce elements heavier than helium, to overcome the barrier of absence of building blocks. Some of those stars would eventually become supernovae, exploding, spewing stardust throughout the galaxy. With the formation of second- and third-generation solar systems, the elements necessary for life came into existence. As the Bible says, "Thou art dust." Life on earth is ultimately composed of dust - stardust. With the exception of the hydrogen in your body, you are made of stardust. Caveat: some heavier elements may also have formed on the periphery of Black Holes. We may be partially composed of matter formed in the chaos near Black Holes.

Additional barriers
The organization of molecules to form life.

Energy barriers:
More power in the engine room: symbiosis produces eukaryotes - cells with more efficient metabolism.
The energy crisis: chlorophyll, production of energy from the sun & the Great die Off with the Oxygen Catastrophe.
Opportunity in catastrophe: ozone
layer forms enabling life on land & aerobic respiration
Greater engine power enables multicellular animals paves the wave for specialized cells including office workers - information cells - neurons & nervous systems


Evolutionary History Compressed to One Year

Deep TimePBS slide show

Sweeping OverviewCarl Sagan's cosmic Calendar

4 billion year history of evolutionCarl Sagan

Three Nervous System Designs

Arthropod Insects, spiders, crustaceans
Ant Aphid Herders BBC
Counting Module in Ant Brain NPR

Arthropods conquered the land, but the evolution of their nervous system was limited by a fatal design flaw. The brain could not grow bigger without strangling the esophagus. thus the largest brained arthropods - smart spiders - can not swallow solid food - they can only swallow liquids. The social insects overcome this barrier by developing colony wide intelligence. This is most developed in bees who communicate the location of flowers with a dance, and ants who farm fungus, herd aphids and take slaves.

Cephalopod Octopus Opens Bottle
Well designed brain, but no way to program it because octopus have no parental care and minimal social interaction.

Vertebrate Jawless Fish to humans
The vertebrate design avoids the arthropod design flaw allowing for the largest brains ever seen on the planet. Mammals (and birds) overcome the cephalopod programing barrier by taking care of - and teaching - their young. But first, the Age of Reptiles had to come to an end. Mammals would be small prey animals to the dinosaurs until a meteorite hit earth and caused a massive die-off opening the way for a burst of mammalian evolution. If that meteorite had not hit Earth 65 million years ago, Troodan might have mastered the globe.

Brainstem & Cranial Nerves


Ape to Human

Jaw muscle defect & human evolution
how a mutation 2.4 million yrs ago may have opened the path for massive brain growth. Until our jaw muscles were rendered weak, to anchor our jaw during the massive forces of chewing, we required a massive skull that closed early - preventing further brain growth. A weak jaw muscle was a barrier to be overcome on the road to a large brained ape.

Language EvolutionMartin Soreno of UC San Diego Dept Cognitive Science presents his theory that language evolved not from alarm calls but from the yoking of "song" to pre-existing visual sequentual processing Presentation of Language theory begins at 30 minutes total video is 57 minutes

SingularityRay Kurzweil forcasts coming merger of humans & computers7 minutes