Timetable / Plan:
- Get recording technology finished & assembled.
- Hardware
- Clean up prototype 2. Test in-chair with Clementine.
- Decide upon a good microelectrode-to-headstage connector with Gary.
- Fit headstage PCB into head-mounted chamber. Select battery and fit that too.
- Assemble one; contract Protronics to assemble 3 more.
- Contract Protronics to assemble 4 receiver boards.
- Software
- Headstage firmware basically complete; need to add in code for LFP measurement & transmission.
- Need some simple sort-client; use existing "Neurocaml" source as a basis. Alternately, use Rppl, inc's open-source "Trellis" electrophysiology suite.
- Integrate UDP reception into the BMI suite.
- Get an rugged all-in-one computer for display of BMI task - at tablet PC in a plexiglas box would be perfect.
- Due: June 30 2009
- Monkeys.
- Test in-cage recording with Clementine. He's a bit long in the tooth now, and does not have enough cells in M1/premotor cortices to do BMI control.
- Select two monkeys, train them on 2D target acquisition with a joystick using Joey's chair and setup. Make sure the monkeys can learn the 2D task in a reasonable amount of time; we don't want to waste time on dumb monkeys.
- Arrange for implantation surgeries this summer, depending on the availability of neurosurgeon.
- Work with Gary Lehew to assemble microelectrodes & head-mounted chamber.
- Get an ethernet drop in the vivarium for transmission of data.
- Due: August 30 2009
- Experiments
- Test & refine task 1 with both monkeys. Allow a maximum of 1 month to learn task 1. Neuron class (x/y/z) selected based on correlational structure (PCA of firing rate).
- Will have to get them to turn off Wifi (in same wireless band as the headstages) in the vivarium.
- Batteries will need to be replaced daily.
- Data will be inspected daily, to eliminate possible confounds / fix bugs / optimize the probability that the monkey learns.
- Expected data rate per headstage, given mean firing rate of 40Hz, full waveform storage, one LFP channel sampled at 1Khz = 3.5Gb / day. 1.5Tb drive, $120, will take 100 days to fill with data from 4 headstages.
- Very occasionally interleave 4-target test trials after the first week of learning, with both 'y' and 'z' neurons used to control the y-axis.
- Test & refine task 2 with both monkeys, in position control; here, record for a minimum of 1 month.
- Adjust cursor and target sizes to maintain task difficulty; measure asymptotic performance in bits/sec.
- Interleave randomly positioned target acquisition with stereotyped target sequences to measure neuronal tuning curves.
- Occasionally perturb cursor to see if there is an internal expectation of cursor motion.
- Switch task 2 to velocity control. Measure performance and learning effects of the switch. Train the monkey on this for at least 2 weeks, or until performance asymptotes.
- Shuffle the neuron class to make it non-topological, and re-train on position control in task 2 (this to test if topology matters). Train monkey for at least 3 weeks.
- Continue recording for as long as it seems worthwhile to do so.
- Due: February 1 2010
- Writing
- Write the DBS paper. This can be done in parallel with many other things, and should take about a month off and on.
- Keep good notes during experiments, write everything up within 1-2 months of finishing the proposed experiments.
- Write thesis.
- Due : June 2010
Contingency Plan:
- Recording technology does not work / cannot be made workable in a reasonable amount of time (Reasonable = 4 months.)
- Use Plexon, record for as long as possible (or permissible given our protocol - 4 hours) while monkey is in chair. If monkeys will not go into REM/SWS in a chair, as seems likely given what I've tried, scratch the sleep specific aim.
- Focus instead on making the simplified BMI work. Will have to assume that neuron identity does not change between sessions.
- Monkey surgery fails.
- Unlikely. If it does happen, we should just get another monkey. As Joey's travails in publishing his paper show, it is best to have two monkeys that learn and perform the same task.
- Even if the implants don't last as long as all the others, the core experiments can be completed within 2 months. Recording quality from even our worst monkey has lasted much longer than this.
- Monkey does not learn the BMI
- Focus on figuring out why the monkeys cannot learn it - start by re-implementing Dawn Taylor's kludgy autoadaptive algorithm, and go from there.
- Focus on sleep. Put a joystick into the cage, and train the monkey on relatively complex sequences of movement to see if there is replay.
- Use the experiment as a springboard to test more complicated decoding algorithms with the help of Zheng.
- There are no signs of replay.
- Try different mathematical methods of looking for replay.
- If still nothing, report that.
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