Cortical stimulation and recording electrode and method for making such electrode

1. A cortical stimulating and recording electrode comprising:

a flexible support element having a head end and a tail end;

a head contact, a tail contact, and a conductive track arranged on the flexible support element, the head contact and the tail contact being respectively arranged at the head end and tail end and being connected by the conductive track, such that said conductive track transmits signals from said head contact to said tail contact and vice versa,

wherein said conductive track is formed of a layer of conductive ink deposited on said flexible support element;

a layer of insulating material overlapping at least the conductive track but not the head contact and the tail contact; and

a conductive contact element overlapping the head contact and a portion of the flexible support element surrounding the head contact, the head contact and the conductive contact element each having a planar shape, a lower surface of the conductive contact element directly contacting an upper surface of the head contact, the conductive contact element being insulated from the conductive track by the layer of insulating material and providing a larger cortical stimulating and recording surface than the upper surface of the head contact.

2. The stimulating and recording electrode according to claim 1 , wherein there is provided a plurality of head contacts, tail contacts, and conductive contact elements, each conductive element connecting one of the plurality of head contacts to one of the plurality of tail contacts, the layer of insulating material providing at least an insulating track interposed between neighboring conductive tracks.

3. The stimulating and recording electrode according to claim 1 , wherein said head contact and said tail contact each comprise a plate having a first layer of conductive ink.

4. The stimulating and recording electrode according to claim 3 , wherein said conductive contact element is produced by binding a plurality of particles of a metal material deposited on said first layer of conductive ink.

5. The stimulating and recording electrode according to claim 1 , wherein said head contact comprises a plate comprising a first layer of the conductive ink in contact with the conductive contact element comprising a second layer of metal material.

6. The stimulating and recording electrode according to claim 5 , wherein said head end has the flexible support element on which the first layer of the conductive ink is deposited intended to provide at least said plate,

a third layer of insulating material being provided that covers partially said head end except for at least a part of said plate, and

the second layer of the metal material being deposited at said plate and completely covering said plate.

7. The stimulating and recording electrode according to claim 1 , wherein said flexible support element is configured as a tubular element.

8. A method of making a cortical stimulating and recording electrode, comprising:

(a) depositing conductive ink on a first layer of flexible material to form a plurality of head contacts, tail contacts, and conductive tracks connecting head contact to each tail contact;

(b) depositing a second layer of insulating material overlapping the conductive tracks but not the head contacts and the tail contacts; and

(c) depositing a third layer of a metal material to form conductive contact elements disposed to overlap the head contacts and portions of the first layer surrounding the head contacts,

wherein the head contacts and the conductive contact elements each have a planar shape, a lower surface of each of the conductive contact elements directly contacting an upper surfaces of a corresponding head contact.

9. The method according to claim 8 , wherein the conductive ink forming the head contacts and/or the tail contacts is deposited after forming said conductive tracks.

10. The method according to claim 8 , wherein depositing the third layer of the metal material comprised depositing the third layer with a galvanic coating.

11. The method according to claim 8 , wherein depositing the third layer of the metal material comprises binding a plurality of particles of the metal material.