@article{THESIS,
      recid = {1656},
      author = {Rajan, Alexander S.},
      title = {INVESTIGATING THE HIERARCHY OF SUBDIVISIONS IN PRIMARY  MOTOR CORTEX, AND BETWEEN PRIMARY MOTOR AND SOMATOSENSORY  CORTICES DURING NATURALISTIC BEHAVIORS},
      publisher = {University of Chicago},
      school = {Ph.D.},
      address = {2016-06},
      number = {THESIS},
      pages = {118},
      abstract = {A popular framework to help comprehend the complicated  connections and interactions between cortical areas is to  place them in a so-called cortical hierarchy [1].  To do so  is helpful not only to describe interactions between  cortical areas and their neural processing, but also to  make predictions.  For example, one would expect a cortical  area that is higher in the hierarchy to have more complex,  or abstract, receptive or projection fields.  Indeed, this  functional difference in cortical areas is a defining  characteristic of cortical hierarchies.  Another defining  characteristic are different patterns of laminar  connections: ascending projections terminate on middle  cortical layers, and descending projections terminate onto  high and low cortical layers, avoiding the middle layers  [2].  Thus, cortical hierarchies, in this dissertation, are  defined by the functional properties of responses, and the  neuroanatomical underpinnings of laminar  connectivity.

Here, I propose using spike-field coherence  to measure the interactions between individual neurons in  one cortical area and populations of neurons in another to  validate the hierarchical structure between cortical areas.   First I will show that these anatomically intertwined  areas are synchronized in a low frequency band, and that  this coherence is not symmetrical.  I expect that rM1-cM1  spike-field coherence will precede cM1-rM1 spike-field  coherence, and likewise that M1-S1 spike-field coherence  will precede S1-M1 coherence.  Additionally, I will provide  support that coherence is a functional mechanism that is  meaningful above and beyond either spikes or local fields.   Finally, I will place these cortical areas in a somatomotor  hierarchy, and discuss their evolutionary origins and roles  in motor control.},
      url = {http://knowledge.uchicago.edu/record/1656},
      doi = {https://doi.org/10.6082/uchicago.1656},
}