Selective recruitment and activation of fiber types in nerves for the control of undesirable brain state changes

1. A method for selectively recruiting a nerve fiber type within a cranial nerve, a peripheral nerve or a spinal root, comprising:

applying a first pressure to a second location of said cranial nerve, said peripheral nerve or said spinal root, said pressure sufficient to substantially block at least one of activation or conduction in at least one of an A-fiber population or a B-fiber population through said second location of said cranial nerve, said peripheral nerve or said spinal root for a blocking time period; and

applying an electrical signal to a first location of said cranial nerve, said peripheral nerve, or said spinal root during said blocking time period, said electrical signal sufficient to activate at least one of a B-fiber population or a C-fiber population at said first location of cranial nerve, said peripheral nerve, or said spinal root.

2. The method of claim 1 wherein the cranial nerve is a vagus nerve and the electrical signal is a therapy for epilepsy, depression, or a cardiovascular disorder.

3. The method of claim 1 , wherein said first pressure is programmably selectable.

4. The method of claim 1 , further comprising:

recording a neurogram relating to impulse conduction through said second location of said cranial nerve, said peripheral nerve or said spinal root; and

determining a first pressure threshold required to substantially block at least one of activation or conduction along at least one of said A fiber population or B fiber population based upon said neurogram.

5. The method of claim 1 , further comprising:

applying said first pressure to substantially block nerve activation or conduction relating to the A-fiber population of said cranial nerve, said peripheral nerve or said spinal root; and

applying a second pressure to substantially block nerve activation or conduction relating to the A-fiber population and the B-fiber population of said cranial nerve.

6. The method of claim 1 , further comprising performing an operation selected from one of heating or cooling said cranial nerve, said peripheral nerve or said spinal root at a third location.

7. A medical device system for selectively stimulating a nerve fiber type within a cranial nerve, a peripheral nerve or a spinal root, comprising:

an electrode coupled to a first location of a cranial nerve, a peripheral nerve or a spinal root, said electrode capable of applying an electrical signal to said first location;

a nerve pressure device coupled to a second location of said cranial nerve, said peripheral nerve or said spinal root, capable of applying a first pressure to the second location;

a medical device operatively coupled to said electrode and said nerve pressure device, said medical device comprising:

a controller

an electrical signal generator configured to apply said electrical signal to the first location of said cranial nerve, said peripheral nerve or said spinal root using said electrode to activate at least one of a B-fiber population or a C-fiber population at said first location of said cranial nerve, said peripheral nerve, or said spinal root; and

a pressure signal generator configured to apply said first pressure to said second location of said cranial nerve, said peripheral nerve or said spinal root using said nerve pressure device, to substantially block at least one of activation or conduction in at least one of an A-fiber population or a B-fiber population at said second location of said cranial nerve, said peripheral nerve or said spinal root.

8. The medical device system of claim 7 , wherein the controller is further configured to determine at least one parameter of the electrical signal.

9. The medical device system of claim 7 , further comprising:

a sensor to receive at least one body data stream;

wherein said electrical signal generator applies at least one of said first pressure and said electrical signal to the first location of said cranial nerve, said peripheral nerve or said spinal root based upon said at least one body data stream.

10. The medical device system of claim 7 , further comprising a user interface, wherein said first pressure is programmably selectable by a user with said user interface.

11. The medical device system of claim 10 , wherein said nerve pressure device is capable of applying a plurality of pressures at said second location, wherein said pressure signal generator is capable of applying said plurality of pressures to said second location using said nerve pressure device, and wherein said plurality of pressures are selectable.

12. The medical device system of claim 11 further comprising a sensor, wherein said plurality of pressures are selectable based on at least one of:

a body data stream provided by a sensor,

an input from said user interface, and

a desired effect on one of brain cortical rhythms and brain excitability.

13. The medical device system of claim 7 , wherein said nerve pressure device comprises a circumneural cuff having an adjustable circumference and length.

14. The medical device system of claim 13 , further comprising a reservoir containing a fluid, wherein the nerve pressure device is configured to apply said first pressure by reversibly receiving or withdrawing said fluid from said reservoir.

15. The medical device system of claim 13 , wherein said circumference of the circumneural cuff is adjusted by an actuator selected from a gear, a sliding member, a switch, a valve, or a spring.

16. The medical device system of claim 7 , wherein said second location is proximal to the brain, relative to the first location, and said electrical signal is applied as a therapy for one of epilepsy and depression; or said second location is proximal to the heart, relative to the first location, and said electrical signal is applied as a therapy for a cardio-vascular condition.

17. The medical device system of claim 7 , further comprising:

a thermal manipulation unit coupled to a third location of said cranial nerve, said peripheral nerve or said spinal root, said thermal manipulation unit capable of heating or cooling said third location;

and wherein said medical device is operatively coupled to said thermal manipulation unit and further comprises a thermal signal generator capable of heating or cooling said third location, to substantially block at least one of activation or conduction in at least one of an A-fiber population or a B-fiber population at said third location.

18. The medical device system of claim 17 , wherein said second location and said third location are the same.