fall 16 - me234 - intro to neuromechanics
me 234 - intro to neuromechanics 16
our brain is not only our softest, but also our least well-understood organ. floating in the cerebrospinal fluid, embedded in the skull, it is almost perfectly isolated from its mechanical environment. not surprisingly, most brain research focuses on the electrical rather than the mechanical characteristics of brain tissue. recent studies suggest though, that the mechanical environment plays an important role in modulating brain function. neuromechanics has traditionally focused on the extremely fast time scales associated with dynamic phenomena on the order of milliseconds. the prototype example is traumatic brain injury where extreme loading rates cause intracranial damage associated with a temporary or permanent loss of function. neurodevelopment, on the contrary, falls into the slow time scales associated with quasi-static phenomena on the order of months. a typical example is cortical folding, where compressive forces between gray and white matter induce surface buckling. to understand the role of mechanics in neuroanatomy and neuromorphology, we begin this course by dissecting mammalian brains and correlate our observations to neurophysiology. we discuss morphological abnormalities including lissencephaly and polymicrogyria and illustrate their morphological similarities with neurological disorders including schizophrenia and autism. then, we address the role of mechanics during brachycephaly, plagiocephaly, tumor growth, and hydrocephalus. last, we explore the mechanics of traumatic brain injury with special applications to shaken baby syndrome.
- 20 % dissection - presentation
- 30 % homework - three homework assignments, 10% each
- 20 % project presentation - graded by the class
- 30 % project report - graded by instructors
|tue||sep||27||introduction to brain anatomy||s01|
|thu||sep||29||introduction to brain mechanics||s02|
|thu||oct||06||brain anatomy - student presentations||s04|
|tue||oct||11||brain mechanics in 1d – elasticity of neurons||s05|
|thu||oct||13||brain mechanics in 3d – elasticity of the brain||s06|
|tue||oct||18||brain mechanics in 3d – brain-skull interaction – craniectomy||s07|
|thu||oct||20||brain mechanics in 3d - viscoelasticity of the brain||s08|
|tue||oct||25||brain growth in 1d – axonal growth||s09|
|thu||oct||27||brain growth in 2d – morphogenesis||s10|
|tue||nov||01||brain swelling in 3d - electrochemistry||s11|
|thu||nov||03||brain swelling in 3d - craniectomy||s12|
|tue||nov||08||brain growth in 3d – physiology and pathologies||s13|
|thu||nov||10||brain surgery - brain doctors at john radcliffe||s14|
|tue||nov||15||brain-fluid interaction – hydrocephalus||s15|
|thu||nov||17||brain damage in 1d – diffuse axonal injury||s16|
|tue||nov||29||brain damage in 3d - traumatic brain injury||s17|
|thu||dec||01||brain damage in 3d – shaken baby syndrome||s18|
|tue||dec||06||final projects - discussion, presentation, evaluation||s19|
|thu||dec||08||final projects - discussion, presentation, evaluation||s20|
|fri||dec||09||final project reports due|
here's the matlab code for brain folding
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a mechanical model predicts morphological abnormalities in the developing human brain.
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van essen dc.
a tension-based theory of morphogenesis and compact wiring in the central nervous system.