fall 14 - me334 - mechanics of the brain
me 334 - mechanics of the brain 14
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 and written report, 10% each
- 30 % homework - three homework assignments, 10% each
- 20 % project presentation - graded by the class
- 30 % project report - graded by instructor
|tue||sep||23||introduction to brain anatomy||s01|
|thu||sep||25||introduction to brain mechanics||s02|
|thu||oct||02||brain anatomy - student presentations||s04|
|tue||oct||07||brain mechanics in 1d – elasticity of neurons||s05|
|thu||oct||09||brain growth in 1d – growth of axons||s06|
|tue||oct||14||brain growth in 2d – morphogenesis||s07|
|thu||oct||16||brain growth in 3d – evolution and development||s08|
|tue||oct||21||brain growth in 3d – physiology and pathology||s09|
|thu||oct||23||brain mechanics in 3d – elasticity of the brain||s10|
|tue||oct||28||brain mechanics in 3d – viscoelasticity and multiple sclerosis||s11|
|thu||oct||30||brain mechanics in 3d – viscoelasticity and aging||s12|
|tue||nov||04||brain tumor growth in 3d – brain tumors||s13|
|thu||nov||06||brain tumor growth in 3d – brain tumors||s14|
|tue||nov||11||brain surgery - craniosynostosis and intracranial pressure||s15|
|thu||nov||13||brain surgery - brain tumors and craniosynostosis||s16|
|tue||nov||18||brain dynamics in 1d - diffuse axonal injury||s17|
|thu||nov||20||brain dynamics in 3d – traumatic brain injury, shaken baby syndrome||s18|
|tue||dec||02||final projects - discussion, presentation, evaluation||s19|
|thu||dec||04||final projects - discussion, presentation, evaluation||s20|
|fri||dec||05||final project reports due|
here's the matlab code for brain folding
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