Sara A. Solla, Northwestern University, Chicago, USA Observing the brain to know ourselves http://obc2012.outofthebox.si/

1. Observing the brain to know ourselves
Sara A. Solla
Northwestern University

2. The human brain

3. The human brain

4. Neurons
About 85 billion neurons,
of which about 15 billion
are in the cortex.

5. Neurons

6. Neurons
electrode

7. Spikes: action potentials

8. Spikes: from single neurons
to multiple neurons

9. Multi Electrode Arrays (MEAs)

10. Reaching tasks

11. Center out task

12. MEA recordings: center out task

13. MEA recordings: multiple targets

14. Converting thoughts into actions
Nicolelis, Nature Reviews Neuroscience (2003)

15. Brain machine interfaces
Idea first proposed by Edward M. Schmidt in 1980: `Single
neuron recording from motor cortex as a possible source of
signals for control of external devices’.
Schmidt, Annals of Biomedical Engineering (1980)

16. Multi Electrode Arrays (MEAs)
Truccolo, Hochberg, Donoghue, Nature Neuroscience (2009)

17. Activity: multiple neurons
110 neurons, M1, hS3

18. Brain machine interfaces

19. Neuroprosthesis
Hochberg, Serruya, Friehs, Mukand, et al, Nature (2006)

20. Neuroprosthesis

21. MEA recordings: center out task

22. Target-dependent population activity
ni Here ni is the number of spikes
fi = emitted by neuron i during a time
D bin of duration D .

23. Decoding direction of motion
for center out task

24. Predicting motion from neural activity
 Simultaneous recordings of population activity
provide insight on the activity of networks of neurons
and its relation to function.
 The mathematical analysis of neural activity associated
with arm reaches allows us to predict motion trajectory.
 The ability to simultaneously record and decode the
activity of large populations of neurons provides a tool for
the restoration of function.

25. Bidirectional Brain Machine Interface
• Incorporate realistic limb dynamics into forward pathway
• Incorporate proprioception in feedback pathway