User:Graeme E. Smith/GreySmith Cerebellar Involvement in Action Protocol 1
GreySmith Cerebellar Involvement in Action Protocol 1
Detecting telegraphing of Motor Neuron Activation to the Cerebellum
Graeme E. Smith, GreySmith Institute of Advanced Studies
This is the first part of a two part set of alternate protocols. In the 1970's David Marr, proposed a set of models of pyramidal areas of the brain. One of those articles was about the Cerebellar Cortex, in which he suggested that activation of the motor areas of the brain, was telegraphed to the cerebellum through the inferior olive. This protocol tries to check that assumption using a Miniature MEG device to monitor the cerebellum of a rodent. It is not known how accurate the MEG device is, and whether it is capable of detecting the telegraphing of a signal to a single purkinje cell, so this protocol may be impractical, in which case there is an alternate protocol using fluorescent dye that might be more practical but which requires more sophistication from the researcher to achieve. The alternate protocol can be found in GSCIAP1a.
This protocol depends on the success of GSLTCAP2, and the capability of the miniature MEG unit for its viability. If the miniature MEG is not sensitive enough to detect the activation of a single purkinje cell in the cerebellum, the protocol is invalid. It depends on the success of GSLTCAP2 because without the involvement of the Laminae V in selection of Action, the presence or absence of activity in the cerebellum is mute. The hypotheses it tests are: Marr's hypothesis that the activation of motor areas is telegraphed to the cerebellum where it impacts directly on the activation of single purkinje cells, and the hypothesis that cerebellar activation acts through the thalamus by influencing laminae V. Further work will be needed to confirm the later hypothesis probably through electrostimulation of the purkinje cell involved, but, this is a good first step.
After preparing a smaller population of rodents for the purposes of control, a statistically significant number of rodents are placed in the miniature MEG device one by one and run through a test that encourages them to move a particular limb. The output of the cerebellar purkinje layer is monitored for activity. What we are looking for is confirmation that the purkinje cells are activated by movement indicating the telegraphing of the motor command to the cerebellum.
As control we want to show that movement of another limb does not result in activation of the same purkinje cell, indicating that the purkinje cells are specific to a particular motor command. Note if this protocol is made invalid by the inability to detect single purkinje cell activations in the cerebellum, then use protocol GSCIAP1a instead.