Book contents
- From Loss to Memory
- From Loss to Memory
- Copyright page
- Dedication
- Contents
- Preface
- Acknowledgments
- 1 Counting Synapses
- 2 Discovering Synaptic Pruning
- 3 Else, Peter’s Mother
- 4 Richard, Peter’s Father, and Peter’s Uncle Fritz
- 5 Greiz: Kriegskinder (Children of War)
- 6 In Braubach, after the War
- 7 Arrival in America
- 8 Harvard Medical School
- 9 Understanding Sleep and Consciousness: Research at the National Institutes of Health
- 10 Entering the Cognitive Revolution: Neuroscience and Cognitive Psychology
- 11 Physician First, Scientist Second?
- 12 Comparative Brain Regions and Synapse Formation
- 13 Stimulating Progress on Developmental Brain Disorders
- 14 Neurodevelopmental Disorders and Schizophrenia: A Role for Synaptic Pruning?
- 15 Early Childhood Education
- 16 Peter and Janellen’s Collaboration
- 17 Microglial Cells and the Mechanisms of Synaptic Pruning
- 18 Looking Forward: Being a Physician and a Scientist
- 19 Parkinson’s Disease and Berlin
- 20 Auf Deutsch: Back to German
- 21 Memories and Reflections at the End: A Return Trip to Greiz
- Glossary
- Index
- References
17 - Microglial Cells and the Mechanisms of Synaptic Pruning
Published online by Cambridge University Press: 10 October 2023
- From Loss to Memory
- From Loss to Memory
- Copyright page
- Dedication
- Contents
- Preface
- Acknowledgments
- 1 Counting Synapses
- 2 Discovering Synaptic Pruning
- 3 Else, Peter’s Mother
- 4 Richard, Peter’s Father, and Peter’s Uncle Fritz
- 5 Greiz: Kriegskinder (Children of War)
- 6 In Braubach, after the War
- 7 Arrival in America
- 8 Harvard Medical School
- 9 Understanding Sleep and Consciousness: Research at the National Institutes of Health
- 10 Entering the Cognitive Revolution: Neuroscience and Cognitive Psychology
- 11 Physician First, Scientist Second?
- 12 Comparative Brain Regions and Synapse Formation
- 13 Stimulating Progress on Developmental Brain Disorders
- 14 Neurodevelopmental Disorders and Schizophrenia: A Role for Synaptic Pruning?
- 15 Early Childhood Education
- 16 Peter and Janellen’s Collaboration
- 17 Microglial Cells and the Mechanisms of Synaptic Pruning
- 18 Looking Forward: Being a Physician and a Scientist
- 19 Parkinson’s Disease and Berlin
- 20 Auf Deutsch: Back to German
- 21 Memories and Reflections at the End: A Return Trip to Greiz
- Glossary
- Index
- References
Summary
In 1937, the Spanish neuroscientist and artist Ramón y Cajal commented on an apparent trial and error period of chaotic dendritic and axonic growth, with most of the resulting connections destined to disappear. But over subsequent decades the prevailing concept among neurobiologists and behavioral biologists was that synaptic connections increase with learning. Peter then rigorously showed in 1979 that after birth and an initial burst of growth in synapse numbers in human infants, there is a regression. He and his collaborators went on to show that these connections disappear at different times, with different kinetics, in distinct regions of the brain. The physical housekeeping task of this process is not small – selecting and eliminating billions of inactive synapses in the developing brain. In some regions of the brain, such as the visual system, the clearance mechanism seems to be relatively rapid over weeks or months. In other regions of the brain, for example in areas of higher cognitive function like the frontal cortex, this process of elimination is apparently more prolonged. What process or system has the intrinsic ability to identify and clear unused synapses? What has the ability to do this in a refined way, by targeting the correct contact sites, and without leaving dead cells and debris behind?
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- Information
- From Loss to MemoryBehind the Discovery of Synaptic Pruning, pp. 109 - 115Publisher: Cambridge University PressPrint publication year: 2023