Multi-electrode channel configurations
An apparatus and method optimizing complex channel configurations to produce minimal channel interactions is provided. The method includes selecting multiple channels from a channel configuration including a plurality of channels, each of the plurality of channels includes multiple electrodes. The method also includes measuring an interaction between selected channels and determining a significance of the measured interaction. The method further includes adjusting a focus of the channel configuration based on the significance of measured interaction, wherein the focus of the channel configuration is not adjusted if the interaction between the selected channels determined to be insignificant. The measuring, determining and adjusting is repeated until the interaction between the selected channels is determined to be insignificant or the magnitude of the interaction is determined to be minimized, thereby optimizing the channel configuration for the selected channels. Another set of channels from the channel configuration is selected and the measuring, determining, adjusting and repeating is performed for each set until full channel configuration is optimized.
1. A method for adjusting weights of a stimulating device comprising a plurality of stimulation channels, wherein each stimulation channel comprises a plurality of electrodes each having a corresponding weight, the method comprising:
selecting a probe channel from amongst the plurality of stimulation channels;
selecting at least one perturbation channel from amongst the plurality of stimulation channels;
applying stimulation via the probe channel using the plurality of electrodes and their corresponding weights;
applying stimulation via the at least one perturbation channel;
measuring an interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel; and
adjusting one or more weights for at least one electrode of at least one of the stimulation channels based on the measured interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel.
2. The method of claim 1 , further comprising:
determining whether the measured interaction exceeds a threshold; and
wherein adjusting the one or more weights comprises: adjusting the one or more weights when the measured interaction is determined to exceed the threshold.
3. The method of claim 2 , further comprising:
determining whether the measured interaction is a constructive or destructive interaction.
4. The method of claim 3 , wherein the adjusting comprises adjusting the weights to increase the focus if the measured interaction is determined to be constructive; and
wherein the adjusting comprises adjusting the weights to decrease the focus if the measured interaction is determined to be destructive.
5. The method of claim 2 , further comprising:
repeating, at the probe channel and at the at least one perturbation channel, the applying, measuring, determining and adjusting until the measured interaction is determined to be below the threshold or the measured interaction is determined to be minimized.
6. The method of claim 5 further comprising:
repeating the selecting a probe channel, selecting at least one perturbation channel, and repeating for each channel of the plurality of channels as the probe channel.
7. The method of claim 2 , wherein each of the probe channel and the at least one perturbation channel have a polarity,
wherein applying a stimulation signal via the at least one perturbation channel comprises
applying a stimulation signal wherein the probe channel and the at least one perturbation channel have the same polarity, and
applying a stimulation signal wherein the probe channel and the at least one perturbation channel have the opposite polarity; and
wherein the measuring comprises:
measuring the interaction between the at least one perturbation channel and the probe channel having the same polarity, and
measuring the interaction between the at least one perturbation channel and the probe channel having opposite polarity.
8. The method of claim 1 , wherein the weights of the stimulation channels are determined using a transimpedance matrix; and
wherein the adjusting one or more weights comprises:
adjusting one or more values of the transimpedance matrix.
9. The method of claim 8 , wherein adjusting one or more values of the transimpedance matrix comprises:
adjusting one or more diagonal terms of the transimpedance matrix.
10. The method of claim 9 , wherein the adjusting one or more diagonal terms of the transimpedance matrix comprises:
decreasing one or more values of the diagonal if the interaction is determined to be constructive; and
increasing one or more values of the diagonal if the interaction is determined to be destructive.
11. The method of claim 1 , wherein:
the action of applying stimulation via the at least one probe channel and the action of applying stimulation via the at least one perturbation channel are executed simultaneously.
12. An apparatus for use in adjusting weights of a stimulating device comprising a plurality of stimulation channels, the apparatus comprising:
a selector configured to select a probe channel from amongst the plurality of stimulation channels, wherein the probe channel comprises a plurality of electrodes each associated with a corresponding weight, and to select at least one perturbation channel from amongst the plurality of stimulation channels;
a stimulation controller configured to transmit information for applying stimulation via the probe channel using the plurality of electrodes and their corresponding weights, and stimulation via the at least one perturbation channel; and
a weight adjuster configured to adjust one or more weights for at least one electrode of at least one of the stimulation channels based on an interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel.
13. The apparatus of claim 12 , wherein the weight adjuster is further configured to measure the interaction between the stimulation from the probe channel and the stimulation of the at least one perturbation channel, determine whether the measured interaction exceeds a threshold, and adjust the one or more weights if the measured interaction is determined to exceed the threshold.
14. The apparatus of claim 13 , wherein weight adjuster is further configured to determine whether the measured interaction is a constructive or destructive interaction.
15. The apparatus of claim 14 , wherein the weight adjuster is further configured to adjust the weights to increase the focus if the measured interaction is determined to be constructive; and
adjust the weights to decrease the focus if the measured interaction is determined to be destructive.
16. The apparatus of claim 13 , wherein each of the probe channel and the at least one perturbation channel have a polarity,
wherein the stimulation controller is further configured to transmit information for applying stimulation regarding applying a stimulation signal wherein the probe channel and the at least one perturbation channel have the same polarity, and applying a stimulation signal wherein the probe channel and the at least one perturbation channel have the opposite polarity; and
wherein the weight adjuster is further configured to measure the interaction between the at least one perturbation channel and the probe channel having the same polarity, and measure the interaction between the at least one perturbation channel and the probe channel having opposite polarity.
17. The apparatus of claim 12 , further comprising:
a weight calculator configured to determine the weights of the stimulation channels using a transimpedance matrix; and
wherein the weight adjuster is further configured to adjust one or more weights by adjusting one or more values of the transimpedance matrix.
18. The apparatus of claim 17 , wherein the weight adjuster is further configured to adjust one or more diagonal terms of the transimpedance matrix.
19. The apparatus of claim 18 , wherein the weight adjuster is further configured to decrease one or more values of the diagonal if the interaction is determined to be constructive; and increase one or more values of the diagonal if the interaction is determined to be destructive.
20. The apparatus of claim 12 , wherein the apparatus is configured such that the stimulation applied via the probe channel and the stimulation applied via the at least one perturbation channel are applied simultaneously.
21. A computer program embodied on a non-transitory computer readable medium, the computer program comprising program code for controlling a processor to execute a method for adjusting weights of a stimulating device comprising a plurality of stimulation channels, wherein each stimulation channel comprises a plurality of electrodes each having a corresponding weight, the method comprising:
selecting a probe channel from amongst the plurality of stimulation channels;
selecting at least one perturbation channel from amongst the plurality of stimulation channels;
applying stimulation via the probe channel using the plurality of electrodes and their corresponding weights;
applying stimulation via the at least one perturbation channel;
measuring an interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel; and
adjusting one or more weights for at least one electrode of at least one of the stimulation channels based on the measured interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel.
22. The computer program of claim 21 , wherein the method comprises:
applying stimulation via the at least one probe channel and applying stimulation via the at least one perturbation channel simultaneously.
23. An apparatus for adjusting weights of a stimulating device comprising a plurality of stimulation channels, wherein each stimulation channel comprises a plurality of electrodes each having a corresponding weight, the apparatus comprising:
means for selecting a probe channel from amongst the plurality of stimulation channels;
means for selecting at least one perturbation channel from amongst the plurality of stimulation channels;
means for applying stimulation via the probe channel using the plurality of electrodes and their corresponding weights;
means for applying stimulation via the at least one perturbation channel;
means for measuring an interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel;
means for adjusting one or more weights for at least one electrode of at least one of the stimulation channels based on the measured interaction between the stimulation via the probe channel and the stimulation via the at least one perturbation channel.
24. The apparatus of claim 23 , wherein the apparatus is configured such that the stimulation applied via the probe channel and the stimulation applied via the at least one perturbation channel are applied simultaneously.