Henry Markram
Encyclopedia
Henry Markram is Director of the Blue Brain
Blue Brain
The Blue Brain Project is an attempt to create a synthetic brain by reverse-engineering the mammalian brain down to the molecular level.The aim of the project, founded in May 2005 by the Brain and Mind Institute of the École Polytechnique Fédérale de Lausanne is to study the brain's architectural...

 Project at École Polytechnique Fédérale de Lausanne
École polytechnique fédérale de Lausanne
The École polytechnique fédérale de Lausanne is one of the two Swiss Federal Institutes of Technology and is located in Lausanne, Switzerland.The school was founded by the Swiss Federal Government with the stated mission to:...

 (EPFL).

He obtained his B.Sc. (Hons) from Cape Town University, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

 under the supervision of Rodney Douglas and his Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...

 from the Weizmann Institute of Science
Weizmann Institute of Science
The Weizmann Institute of Science , known as Machon Weizmann, is a university and research institute in Rehovot, Israel. It differs from other Israeli universities in that it offers only graduate and post-graduate studies in the sciences....

, Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

, under the supervision of Menahem Segal. During his Ph.D. work, he discovered a link between acetylcholine
Acetylcholine
The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...

 and memory mechanisms by showing that acetylcholine modulates the primary receptor linked to synaptic plasticity
Synaptic plasticity
In neuroscience, synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength in response to either use or disuse of transmission over synaptic pathways. Plastic change also results from the alteration of the number of receptors located on a synapse...

.

Markram went to the United States as a Fulbright Scholar at the National Institutes of Health
National Institutes of Health
The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...

 (NIH), where he studied ion channels on synaptic vesicles. He then went as a Minerva Fellow to the Laboratory of Bert Sakmann at the Max Planck Institute, Heidelberg
Heidelberg
-Early history:Between 600,000 and 200,000 years ago, "Heidelberg Man" died at nearby Mauer. His jaw bone was discovered in 1907; with scientific dating, his remains were determined to be the earliest evidence of human life in Europe. In the 5th century BC, a Celtic fortress of refuge and place of...

, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, where he discovered calcium transients in dendrites evoked by sub-threshold activity, and by single action potentials propagating back into dendrites. He also began studying the connectivity between neurons, describing in great detail how layer 5 pyramidal neurons are interconnected.

Some of his work altered the relative timing of single pre- and post-synaptic action potentials to reveal a learning mechanism operating between neurons where the relative timing in the millisecond range affects the coupling strength between neurons. The importance of such timing has been reproduced in many brain regions and is known as spike timing-dependent synaptic plasticity
Spike timing dependent plasticity
Spike-timing-dependent plasticity is a biological process that adjusts the strength of connections between neurons in the brain. The process adjusts the connection strengths based on the relative timing of a particular neuron's output and input action potentials...

 (STDP).

Markram was appointed assistant professor at the Weizmann Institute of Science
Weizmann Institute of Science
The Weizmann Institute of Science , known as Machon Weizmann, is a university and research institute in Rehovot, Israel. It differs from other Israeli universities in that it offers only graduate and post-graduate studies in the sciences....

, where he started systematically dissecting out the neocortical column. He discovered that synaptic learning can also involve a change in synaptic dynamics (called redistribution of synaptic efficacy) rather than merely changing the strengths of connections. He also studied principles governing neocortical microcircuit structure, function, and emergent dynamics. Together with Wolfgang Maass he developed the so-called theory of liquid computing, or high entropy computing.

In 2002 he moved to EPFL as full professor and founder/director of the Brain Mind Institute and Director of the Center for Neuroscience and Technology. At the BMI, in the Laboratory for Neural Microcircuitry, Markram continues to study the organisation of the neocortical column, develops tools to carry out multi-neuron patch clamp
Patch clamp
The patch clamp technique is a laboratory technique in electrophysiology that allows the study of single or multiple ion channels in cells. The technique can be applied to a wide variety of cells, but is especially useful in the study of excitable cells such as neurons, cardiomyocytes, muscle...

recordings combined with laser and electrical stimulation as well as multi-site electrical recording, chemical imaging and gene expression.

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