SYSTEMS AND METHODS FOR APPLYING SIGNALS, INCLUDING CONTRALESIONAL SIGNALS, TO NEURAL POPULATIONS

• US 20070288072A1
• Filed: 04/06/2007
• Published: 12/13/2007
• Est. Priority Date: 04/11/2006
• Status: Active Grant

• Current Assignee: Advanced Neuromodulation Systems Incorporated (Abbott Laboratories)
• Original Assignee: Northstar Neuroscience, Inc.
• Inventors: Pascual-Leone, Alvaro, Himes, David, Sloan, Leif, Gliner, Bradford
• Granted Patent: US 8,926,676 B2
• Time in Patent Office: Days
• US Class Current: 607/88
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/36103 Neuro-rehabilitation; Repair or reorganisation of neural tissue, e.g. after stroke
• CPC Class Codes: A61N 1/3615 Intensity
• CPC Class Codes: A61N 1/36171 Frequency

Abstract

Systems and methods for applying signals, including contralesional electromagnetic signals, to neural populations, are disclosed. A particular method can be directed to treating a patient having a subject neural population in a first (e.g., ipsilesional) hemisphere of the brain, with the subject neural population having, or previously having, a functionality capable of being improved. The method can include directing an application of electromagnetic signals at least proximate to a target neural population at a second (e.g., contralesional) hemisphere of the brain to at least constrain a functionality of the target neural population, which has transcallosal communication with the first hemisphere.

Claims

1. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of electromagnetic signals at least proximate to a target neural population via at least one electrode implanted in the patient to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

2. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to depress the target neural population.

3. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to inhibit the target neural population.

4. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to depotentiate the target neural population.

5. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to disrupt neural processes carried out by the target neural population.

6. The method of claim 1 wherein directing the application of electromagnetic signals includes inhibiting the target neural population from assuming functions normally performed by the subject neural population.

7. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at theta-burst frequencies.

8. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

9. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 4 Hz to about 10 Hz.

10. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at a sub-threshold level for the target neural population.

11. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at 80% or less of a threshold level for the target neural population.

12. The method of claim 1 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at 80% or more of a threshold level for the target neural population.

13. The method of claim 1 wherein the subject neural population includes a subject neural population having a functionality that is reduced or eliminated at least in part as a result of neurological damage to the brain.

14. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first, facilitatory electromagnetic signals to the first hemisphere; and

directing an application of second electromagnetic signals at least proximate to a target neural population via a transcranial magnetic device to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

15. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

16. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 4 Hz to about 10 Hz.

17. The method of claim 14 wherein directing the application of the first electromagnetic signals includes directing the application of electromagnetic signals at a frequency of at least 20 Hz.

18. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to depress the target neural population.

19. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to inhibit the target neural population.

20. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to depotentiate the target neural population.

21. The method of claim 14 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to disrupt neural processes carried out by the target neural population.

22. The method of claim 14, wherein directing the application of the second electromagnetic signals includes inhibiting the target neural population from assuming functions normally performed by the subject neural population.

23. The method of claim 14 wherein directing the application of the second electromagnetic signals is performed before directing the application of the first electromagnetic signals.

24. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first, facilitatory electromagnetic signals to the first hemisphere; and

directing an application of second electromagnetic signals at least proximate to a target neural population to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

25. The method of claim 24 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals at least proximate to the subject neural population.

26. The method of claim 24 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals in conjunction with, and at approximately the same time as, directing the application of the second electromagnetic signals.

27. The method of claim 24 wherein directing the application of the first electromagnetic signals includes directing the application of the second electromagnetic signals at a frequency of at least 20 Hz.

28. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to inhibit the target neural population.

29. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to depotentiate the target neural population.

30. The method of claim 24 wherein directing the application of the second electromagnetic signals includes inhibiting the target neural population from assuming functions normally performed by the subject neural population.

31. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at theta-burst frequencies.

32. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

33. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 4 Hz to about 10 Hz.

34. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a sub-threshold level for the target neural population.

35. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals via an electrode implanted within the patient'"'"'s skull.

36. The method of claim 24 wherein directing the application of the first, the second, or both the first and the second electromagnetic signals includes directing the application of electromagnetic signals via a transcranial magnetic device.

37. The method of claim 24 wherein directing the application of the first, the second, or both the first and the second electromagnetic signals includes directing the application of electromagnetic signals via a one or more electrodes implanted within the patient'"'"'s skull.

38. The method of claim 24, further comprising introducing a chemical agent to the target neural population and wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals while the target neural population is exposed to the chemical agent.

39. The method of claim 38, further comprising selecting the chemical agent to includes at least one of norepinephrine and an adenosine A1 receptor antagonist.

40. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that would be expected to assume at least some functionality of the subject neural population in the absence of inhibitory electromagnetic signals.

41. The method of claim 24 wherein directing the application of facilitatory electromagnetic signals includes directing the application of excitatory signals.

42. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that is homologous to the subject neural population.

43. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that is homologous to the subject neural population, and wherein the method further comprises directing the application of facilitatory signals to a non-homologous neural population at the second hemisphere.

44. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that is non-homologous to the subject neural population, and wherein the method further comprises directing the application of facilitatory signals to a homologous neural population at the second hemisphere.

45. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that is not homologous to the subject neural population.

46. The method of claim 24 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a target neural population that is not homologous to the subject neural population, and has more transcallosal connections than does a neural population that is homologous to the subject neural population.

47. The method of claim 46 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to the contralesional premotor cortex.

48. The method of claim 24, further comprising directing the application of third, facilitatory electromagnetic signals at least proximate to the target neural population.

49. The method of claim 24, further comprising directing the application of third, facilitatory electromagnetic signals at least proximate to the target neural population after directing the application of inhibitory electromagnetic signals at least proximate to the target neural population.

50. The method of claim 24 wherein directing the application of the second electromagnetic signals to the target neural population includes directing the application of the second electromagnetic signals for a target period of time associated with an expected improvement in functionality of neurons at the first hemisphere, and wherein the method further comprises directing the application of third, facilitatory electromagnetic signals to the target neural population after the target period of time has elapsed.

51. The method of claim 24, further comprising:

detecting an improvement in functionality of neurons at the first hemisphere; and

after detecting an improvement in functionality of the neurons at the first hemisphere, directing the application of third, facilitatory electromagnetic signals to the target neural population.

52. The method of claim 24 wherein directing the application of the first electromagnetic signals to the first hemisphere includes directing the application of the first electromagnetic signals simultaneously with directing the application of the second electromagnetic signals to the target neural population, and wherein the method further comprises:

detecting an improvement in functionality of neurons at the first hemisphere; and

after detecting an improvement in functionality of neurons at the first hemisphere, directing the application of third, facilitatory electromagnetic signals to the target neural population.

53. The method of claim 24, further comprising directing the patient to undergo adjunctive therapy as part of a treatment regimen that also includes the application of the first and the second electromagnetic signals.

54. The method of claim 24, further comprising:

directing the patient to undergo adjunctive therapy as part of a treatment regimen that also includes the application of the first and the second electromagnetic signals; and

selecting a characteristic of at least one of the first and the second electromagnetic signals based at least in part on a characteristic of the adjunctive therapy, or selecting a characteristic of the adjunctive therapy based at least in part on a characteristic of at least one of the first and the second electromagnetic signals, or both.

55. The method of claim 24, further comprising identifying the patient as having a subject neural population affected by a stroke.

56. The method of claim 24, further comprising identifying the patient as having a subject neural population affected by a neurological disease.

57. The method of claim 24, further comprising identifying the patient as having a subject neural population affected by a lesion.

58. The method of claim 24 wherein directing the application of electromagnetic signals is performed by computer-based instructions.

59. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first, facilitatory electromagnetic signals to the first hemisphere; and

directing an application of second electromagnetic signals at least proximate to a target neural population via an implanted electrode to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

60. The method of claim 59 wherein the electrode includes the second of two electrodes, and wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals via a first electrode implanted at the first hemisphere.

61. The method of claim 59 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals to inhibit the target neural population.

62. The method of claim 59, wherein directing the application of the second electromagnetic signals includes inhibiting the target neural population from assuming functions normally performed by the subject neural population.

63. The method of claim 59 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

64. The method of claim 59 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 4 Hz to about 10 Hz.

65. The method of claim 59 wherein directing the application of the second electromagnetic signals includes directing the application of electromagnetic signals at a sub-threshold level for the target neural population.

66. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first electromagnetic signals to a first target neural population via at least one electrode implanted in the patient, the first target neural population being at the first hemisphere of the brain; and

directing an application of second electromagnetic signals to a second target neural population via transcranial magnetic stimulation, the second target neural population being located at a second hemisphere of the brain and having transcollosal communication with the first hemisphere.

67. The method of claim 66 wherein directing the application of the first electromagnetic signals includes directing facilitatory electromagnetic signals.

68. The method of claim 66 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to at least constrain a functionality of the second target neural population.

69. The method of claim 68 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

70. The method of claim 68 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals at a frequency of from about 4 Hz to about 10 Hz.

71. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first electromagnetic signals at least proximate to a target neural population to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere; and

directing an application of second, facilitatory electromagnetic signals to the second hemisphere.

72. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to a target neural population that is homologous to the subject neural population.

73. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to a target neural population that is non-homologous to the subject neural population.

74. The method of claim 71, further comprising directing the application of third, facilitatory electromagnetic signals to the first hemisphere.

75. The method of claim 71 wherein directing the application of the second electromagnetic signals includes directing the application of facilitatory electromagnetic signals after directing the application of the first electromagnetic signals.

76. The method of claim 71 wherein the target neural population is a first target neural population, and wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to a second target neural population at the second hemisphere, the second target neural population being different than the first target neural population.

77. The method of claim 71 wherein the target neural population is a first target neural population, and wherein directing the application of the second electromagnetic signals includes simultaneously directing the application of the second electromagnetic signals to a second target neural population at the second hemisphere, the second target neural population being different than the first target neural population.

78. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to inhibit the target neural population.

79. The method of claim 71, wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to inhibit the target neural population from assuming functions normally performed by the subject neural population.

80. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

81. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of electromagnetic signals at a sub-threshold level for the target neural population.

82. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of electromagnetic signals via a transcranial magnetic device.

83. The method of claim 71 wherein directing the application of the first electromagnetic signals includes directing the application of electromagnetic signals via an electrode implanted within the patient'"'"'s skull.

84. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of electromagnetic signals at least proximate to a target neural population via at least one electrode implanted within the patient'"'"'s skull to at least constrain functionality of the target neural population, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere; and

directing an application of an adjunctive therapy to the patient as part of a treatment regimen that includes the electromagnetic signals and the adjunctive therapy.

85. The method of claim 84 wherein directing the application of an adjunctive therapy includes directing the patient to engage in a motor task.

86. The method of claim 84 wherein directing the application of an adjunctive therapy includes directing the patient to engage in a cognitive task.

87. The method of claim 84 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to depress the target neural population.

88. The method of claim 84 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to inhibit the target neural population.

89. The method of claim 84 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to depotentiate the target neural population.

90. The method of claim 84 wherein directing the application of electromagnetic signals includes inhibiting the target neural population from assuming functions normally performed by the subject neural population.

91. The method of claim 84 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at a frequency of from about 0.1 Hz to about 20 Hz.

92. The method of claim 84 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals at a sub-threshold level for the target neural population.

93. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first electromagnetic signals to a first target neural population during a first period of time, the first target neural population being at the first hemisphere of the brain; and

directing an application of second electromagnetic signals to a second target neural population during a second period of time different than the first period of time, the second target neural population being located at a second hemisphere of the brain and having transcollosal communication with the first hemisphere.

94. The method of claim 93 wherein the second period of time includes a practitioner-directed therapy session, and wherein the first period of time is outside the practitioner-directed therapy session.

95. The method of claim 94, further comprising directing the patient to undergo behavioral therapy during the second period of time.

96. The method of claim 93 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to at least constrain a functionality of the second target neural population.

97. The method of claim 93 wherein directing the application of the first, the second or both the first and the second electromagnetic signals includes directing the application of the electromagnetic signals via a transcranial magnetic device.

98. The method of claim 93 wherein directing the application of the first, the second or both the first and the second electromagnetic signals includes directing the application of the electromagnetic signals via an electrode implanted in the patient.

99. The method of claim 93, further comprising automatically triggering the first electromagnetic signals based at least in part on a patient activity.

100. The method of claim 93, further comprising automatically triggering the first electromagnetic signals based at least in part on a rehabilitative patient activity.

101. The method of claim 93 wherein the first time period includes a first pattern of signal cycling and wherein the second time period includes a second pattern of signal cycling different than the first.

102. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first, facilitatory electromagnetic signals to the brain in accordance with a first set of signal delivery parameters; and

directing an application of second electromagnetic signals to a target neural population to least constrain a functionality of the target neural population in accordance with a second set of signal delivery parameters, the second set of signal delivery parameters being different than the first set of signal delivery parameters, and the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

103. The method of claim 102 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to the first hemisphere.

104. The method of claim 102 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to the second hemisphere.

105. The method of claim 102 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals at about 70% of a threshold level of neurons in the target neural population.

106. The method of claim 102 wherein the first electromagnetic signals are applied in one of a bipolar and a unipolar manner, and wherein the second electromagnetic signals are applied in the other of the bipolar and unipolar manner.

107. The method of claim 102 wherein the first electromagnetic signals are applied in one of a cathodal and an anodal matter, and wherein the second electromagnetic signals are applied in the other of the cathodal and anodal manner.

108. The method of claim 102 wherein the first set of signal delivery parameters includes signals that vary in a first temporal manner, and wherein the second set of signal delivery parameters includes signals that vary in a second temporal manner different than the first temporal manner.

109. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of electromagnetic signals at least proximate to a target neural population to at least constrain a functionality of the target neural population, the target neural population being at a second hemisphere of the brain and being non-homologous with respect to the subject neural population, the target population having transcallosal communication with the first hemisphere.

110. The method of claim 109 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals via at least one electrode implanted in the patient.

111. The method of claim 109 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals via a transcranial magnetic device.

112. The method of claim 109, further comprising directing the application of facilitatory stimulation to a homologous neural population at the second hemisphere.

113. The method of claim 109 wherein directing the application of electromagnetic signals includes directing the application of electromagnetic signals to a target neural population that is not homologous with respect to the subject neural population, and has more transcallosal connections than does a neural population that is homologous with respect to the subject neural population.

114. The method of claim 109 wherein the subject neural population includes a neural population at the motor cortex, and wherein directing the application of electromagnetic signals to the target neural population includes directing the application of electromagnetic signals to the contralesional premotor cortex.

115. The method of claim 109, further comprising directing the application of facilitatory electromagnetic signals at least proximate to the target neural population.

116. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

preferentially directing electromagnetic signals to a first target neural population having hypoactive spontaneous electrical activity levels, the first target neural population being located at the first hemisphere; and

directing the application of electromagnetic signals at least proximate to a second target neural population located at a second hemisphere of the brain and having transcallosal communication with the first hemisphere, only after spontaneous electrical activity levels of the second target neural population change from hyperactive levels to become hypoactive levels.

117. The method of claim 116 wherein directing the application of electromagnetic signals at least proximate to the second target neural population includes directing the application of electromagnetic signals to at least constrain a functionality of the target neural population.

118. The method of claim 116 wherein directing the application of electromagnetic signals at least proximate to the second target neural population includes directing the application of electromagnetic signals to facilitate a functionality of the target neural population.

119. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing the application of first electromagnetic signals to a first target neural population at the first hemisphere of the brain; and

directing the application of second electromagnetic signals to a second target neural population at a second hemisphere of the brain using transcranial direct current.

120. The method of claim 119 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to at least one electrode implanted in the patient at the first hemisphere.

121. The method of claim 119 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to the first target neural population via a transcranial magnetic technique.

122. The method of claim 119 wherein directing the application of the first electromagnetic signals includes directing the application of the first electromagnetic signals to the first target neural population via a transcranial direct current technique.

123. The method of claim 119 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to at least constrain a functionality of the second target neural population.

124. The method of claim 123 wherein directing the application of the second electromagnetic signals includes directing the application of cathodal electromagnetic signals.

125. The method of claim 119 wherein directing the application of the second electromagnetic signals includes directing the application of the second electromagnetic signals to facilitate a functionality of the second target neural population.

126. The method of claim 125 wherein directing the application of the second electromagnetic signals includes directing the application of anodal electromagnetic signals.

127. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing the application of aperiodic electromagnetic signals at least proximate to a target neural population via at least one electrode implanted in the patient, the target neural population being at a second hemisphere of the brain and having transcallosal communication with the first hemisphere.

128. The method of claim 127 wherein directing the application of aperiodic electromagnetic signals includes at least constraining a functionality of the target neural population.

129. The method of claim 127 wherein directing the application of aperiodic electromagnetic signals includes directing the application of pseudo-randomly varying signals.

130. The method of claim 127 wherein directing the application of aperiodic electromagnetic signals includes directing the application of chaotically varying signals.

131. The method of claim 127 wherein the electromagnetic signals are the first electromagnetic signals and wherein the method further comprises directing the application of facilitatory electromagnetic signals to the first hemisphere.

132. The method of claim 127 wherein directing the application of facilitatory electromagnetic signals includes directing the application of facilitatory electromagnetic signals at least proximate to the subject neural population.

133. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing an application of first facilitatory electromagnetic signals to the first hemisphere; and

directing an application of second facilitatory electromagnetic signals at least proximate to a target neural population at a second hemisphere of the brain, the target neural population having transcallosal communication with the first hemisphere.

134. The method of claim 133, further comprising directing an application of electromagnetic signals at least proximate to the target neural population to at least constrain a functionality of the target neural population, prior to directing the application of the second facilitatory electromagnetic signals.

135. The method of claim 133, further comprising using a first signal delivery device to apply the first facilitatory signals and using a second signal delivery device, different than the first, to deliver the second facilitatory signals.

136. The method of claim 133 wherein the first facilitatory signals are directed to a first site of a site pair, and wherein the second facilitatory signals are directed to a second site of the site pair, and wherein the method further comprises:

directing signals to multiple site pairs during a test phase;

selecting one or more of the multiple site pairs based at least in part on patient response during the test phase; and

applying electromagnetic signals to the one or more selected site pairs during a therapy phase.

137. The method of claim 133 wherein applying the first and second signals includes applying one of the first and second signals in a theta burst pattern, and applying the other of the first and second signals in a non-theta burst pattern.

138. A method for treating a patient having a subject neural population in a first hemisphere of the patient'"'"'s brain, wherein the subject neural population has or had a functionality that is capable of being improved, the method comprising:

directing signals to multiple site pairs during a first phase, with each site pair including a first site at the first hemisphere of the patient'"'"'s brain and a second site at a second hemisphere of the patient'"'"'s brain;

selecting one or more of the multiple site pairs based at least in part on patient response during the first phase; and

applying electromagnetic signals to the one or more selected site pairs during a second phase.

139. The method of claim 138 wherein directing signals to multiple site pairs during a first phase includes, for at least one site pair, directing facilitatory signals to one of the first and second sites, and directing inhibitory signals to the other of the first and second sites.

140. The method of claim 138 wherein directing signals to multiple site pairs during a first phase includes, for at least one site pair, directing signals at a first polarity to one of the first and second sites, and directing signals at a second polarity different than the first to the other of the first and second sites.

141. The method of claim 138 wherein directing signals to multiple site pairs during a first phase includes, for at least one site pair, directing signals to a first site at the first hemisphere and a non-homologous second site at the second hemisphere.

142. The method of claim 138 wherein directing signals during the first phase includes directing signals via TMS or tDCS, and wherein directing signals during the second phase includes directing signals via at least one implanted electrode.

143. The method of claim 138 wherein selecting one or more of the multiple site pairs includes selecting based at least in part on which site pair is expected to produce a patient response with a lower signal delivery power than other site pairs.

144. The method of claim 143 wherein selecting one or more of the multiple site pairs includes selecting based at least in part on which site pair is expected to produce a motor response in the patient with a lower signal delivery power than other site pairs.

145. The method of claim 138, further comprising engaging the patient in an adjunctive therapy during the second phase but not during the first phase.

146. A computer-readable medium for treating a neurological dysfunction, comprising:

a detection component configured to receive an indication of a change in functionality of a subject neural population of a patient'"'"'s brain, the subject neural population having a functionality that is capable of being improved; and

a direction component configured to direct a change in an electromagnetic signal applied to the patient'"'"'s brain, based at least in part on the indication received by the detection component, the change being between an inhibitory signal and a facilitatory signal.

147. The computer-readable medium of claim 146 wherein the direction component is configured to direct a change in a frequency with which electromagnetic signals are directed to the patient'"'"'s brain.

148. The computer-readable medium of claim 146 wherein the direction component is configured to direct a higher signal frequency for facilitatory signals than for inhibitory signals.

149. A computer-readable medium for treating a neurological dysfunction, comprising:

a timing component that includes information corresponding to expected times at which a change in electromagnetic signals is expected to increase functionality of an subject neural population of a patient'"'"'s brain, the subject neural population having a functionality that is capable of being improved; and

a direction component configured to direct a change in the electromagnetic signals applied to the patient'"'"'s brain, based at least in part on the indication received by the detection component, the change being between an inhibitory signal and a facilitatory signal.

150. The computer-readable medium of claim 149 wherein the direction component is configured to direct a change in a frequency with which electromagnetic signals are directed to the patient'"'"'s brain.

151. The computer-readable medium of claim 149 wherein the direction component is configured to direct a higher signal frequency for facilitatory signals than for inhibitory signals.