Abstract: Deep Brain Stimulation (DBS) electrodes are positioned within (or adjacent to) white matter fiber tracts in a brain of patient. The DBS electrodes may be positioned near one or more stimulation sites within the white matter fiber tracts. The stimulation sites may be selected based on the disorder of the patient. In some examples, the stimulation sites may be selected based on one or more symptoms of the patient. In some examples, additional electrodes may be positioned in another area to collect bioelectrical brain signals. The area in which the additional electrodes are placed is an area that is different from the stimulation site but is targeted by stimulation therapy provided at the stimulation site.

Abstract: A characteristic of a washout period following the delivery of therapy to a patient according to a therapy program may be determined based on a physiological parameter of the patient. A washout period includes the period of time during which a carryover effect from the therapy dissipates. The washout period characteristic may include, for example, a duration of the washout period, an amplitude or a trend in a physiological signal during the washout period or a power level or a ratio of power levels in frequency bands of the physiological signal. In some embodiments, washout period characteristics associated with a plurality of therapy programs may be used to compare the programs. In other embodiments, a washout period characteristic may be used to determine a mood state of the patient and, in some cases, modify a therapy program. Monitoring a washout period may also be useful for timing therapy program trials.

Abstract: A therapy system for managing a psychiatric disorder of the patient may be controlled based on a patient mood state. Therapy may be delivered to a patient according to a therapy program, and a physiological parameter of the patient may be monitored during or after therapy delivery. The patient mood state may be determined based on the monitored physiological parameter, and the therapy delivery may be controlled based on the determined mood state. In some embodiments, the therapy delivery is stopped prior to determining the patient mood state and the therapy delivery is restarted upon detecting a negative mood state. In other embodiments, therapy delivery is delivered until a positive mood state is detected, at which point the therapy delivery may be stopped.

Abstract: Bioelectrical brain signals may be monitored at one more regions of the brain of a patient by a medical device. The monitored bioelectrical signals may be used to select one or more therapy cycle parameters, e.g., on cycle duration and/or off cycle duration, for therapy delivered to treat a patient disorder. In one example, the off cycle duration of a therapy may be selected based on the washout period determined from sensed brain signals of the patient following delivery of therapy during an on cycle. In another example, the on cycle duration and/or off cycle duration of a therapy may be selected to maintain the value of one or more characteristics of a brain signal (e.g., cortical activity) of patient within a threshold range of a target value defined for the characteristic that is associated with effective treatment of the patient disorder.

Abstract: In some examples of selecting a target therapy delivery site for treating a patient condition, a relatively high frequency electrical stimulation signal is delivered to at least two areas within a first region (e.g., an anterior nucleus of the thalamus) of a brain of a patient, and changes in brain activity (e.g., as indicated by bioelectrical brain signals) within a second region (e.g., a hippocampus) of the brain of the patient in response to the delivered stimulation are determined. The target therapy delivery site, an electrode combination, or both, may be selected based on the changes in brain activity.

Abstract: Various embodiments concern delivering electrical stimulation to the brain at a plurality of different levels of a stimulation parameter and sensing a bioelectrical response of the brain to delivery of the electrical stimulation for each of the plurality of different levels of the stimulation parameter. A suppression window of the stimulation parameter can be identified as having a suppression threshold as a lower boundary and an after-discharge threshold as an upper boundary based on the sensed bioelectrical responses. A therapy level of the stimulation parameter can be set for therapy delivery based on the suppression window. The therapy level of the stimulation parameter may be set closer to the suppression threshold than the after-discharge threshold within the suppression window. Data for hippocampal stimulation demonstrating a suppression window is presented.

Abstract: Various embodiments concern delivering electrical stimulation to the brain at a plurality of different levels of a stimulation parameter and sensing a bioelectrical response of the brain to delivery of the electrical stimulation for each of the plurality of different levels of the stimulation parameter. A suppression window of the stimulation parameter can be identified as having a suppression threshold as a lower boundary and an after-discharge threshold as an upper boundary based on the sensed bioelectrical responses. A therapy level of the stimulation parameter can be set for therapy delivery based on the suppression window. The therapy level of the stimulation parameter may be set closer to the suppression threshold than the after-discharge threshold within the suppression window. Data for hippocampal stimulation demonstrating a suppression window is presented.

Abstract: In some examples of selecting a target therapy delivery site for treating a patient condition, a relatively high frequency electrical stimulation signal is delivered to at least two areas within a first region (e.g., an anterior nucleus of the thalamus) of a brain of a patient, and changes in brain activity (e.g., as indicated by bioelectrical brain signals) within a second region (e.g., a hippocampus) of the brain of the patient in response to the delivered stimulation are determined. The target therapy delivery site, an electrode combination, or both, may be selected based on the changes in brain activity.

Abstract: In some examples of selecting a target therapy delivery site for treating a patient condition, a relatively high frequency electrical stimulation signal is delivered to at least two areas within a first region (e.g., an anterior nucleus of the thalamus) of a brain of a patient, and changes in brain activity (e.g., as indicated by bioelectrical brain signals) within a second region (e.g., a hippocampus) of the brain of the patient in response to the delivered stimulation are determined. The target therapy delivery site, an electrode combination, or both, may be selected based on the changes in brain activity.

Abstract: A method for selectively interacting with electrically excitable tissue of a patient is provided. In one configuration, an implantable pulse generator with a number of outputs and an array of electrodes with a number of electrodes being greater than the number of outputs may be implanted in a patient. An extension unit may be implanted between the implantable pulse generator and array. The extension unit acts to electrically couple the inputs of implantable pulse generator with the greater number of electrodes in the array so that the output sources are coupled to a portion of the electrodes.

Abstract: Bioelectrical brain signals may be monitored at one more regions of the brain of a patient by a medical device. The monitored bioelectrical signals may be used to select one or more therapy cycle parameters, e.g., on cycle duration and/or off cycle duration, for therapy delivered to treat a patient disorder. In one example, the off cycle duration of a therapy may be selected based on the washout period determined from sensed brain signals of the patient following delivery of therapy during an on cycle. In another example, the on cycle duration and/or off cycle duration of a therapy may be selected to maintain the value of one or more characteristics of a brain signal (e.g., cortical activity) of patient within a threshold range of a target value defined for the characteristic that is associated with effective treatment of the patient disorder.

Abstract: Techniques for varying stimulus parameters used in neural stimulation to improve therapy efficacy, minimize energy consumption, minimize undesired side effects, and minimize loss of therapeutic effectiveness due to physiologic tolerance to stimulation. Neural stimulation is provided having a stimulation amplitude, a stimulation frequency, a stimulation pulse duration, an electrode-firing pattern, and a set of electrode-firing-polarity conditions. At least one of the stimulation parameters is pseudo-randomly varied. A second stimulation parameter is changed based upon having pseudo-randomly varied the first stimulation parameter and based upon a predetermined relationship specifying how changes in the first parameter affect desirable values for the second parameter.

Abstract: Techniques for varying stimulus parameters used in neural stimulation to improve therapy efficacy, minimize energy consumption, minimize undesired side effects, and minimize loss of therapeutic effectiveness due to physiologic tolerance to stimulation. Neural stimulation is provided having a stimulation amplitude, a stimulation frequency, a stimulation pulse duration, an electrode-firing pattern, and a set of electrode-firing-polarity conditions. At least one of the stimulation parameters is pseudo-randomly varied. A second stimulation parameter is changed based upon having pseudo-randomly varied the first stimulation parameter and based upon a predetermined relationship specifying how changes in the first parameter affect desirable values for the second parameter.

Abstract: An anxiety episode may be identified as being an anxiety event that is attributable to an anxiety disorder of a patient based on the patient activity associated with the anxiety episode. The patient activity may include, for example, patient motion, patient posture or voice activity. Detection of the activity component during an anxiety episode can help distinguish between a general anxiety state and an anxiety event that differs from the general anxiety state. Examples of anxiety events include, for example, an occurrence of a compulsion or a panic attack. The detected anxiety events can be used to evaluate an anxiety disorder of a patient, evaluate therapy programs implemented by a medical device to treat the anxiety disorder, or control therapy delivery. In some examples, a mood state transition is detected based on patient activity information and therapy delivery is controlled based on the detection of the mood state transition.

Abstract: Stuttering-treatment techniques using neural stimulation and/or drug delivery. One or more electrodes and/or a catheter are implanted adjacent to sites in the brain. A signal generator and the electrode deliver stimulation to a first site. A pump and the catheter deliver one or more therapeutic drugs to a second site. The first and second sites could be: the supplementary motor area, the centromedian circuit, the dorsomedial nuclei, the lateral prefrontal circuit, or other paramedian thalamic and midbrain nuclei. The stuttering treatment could be performed via periodic transcranial magnetic stimulation. A sensor, located near the patient's vocal folds, can be used for generating a signal responsive to activity of the patient's speech-producing muscles. A controller adjusts one or more stimulation parameters in response to the signal from the sensor.

Abstract: Brain signals may be monitored at different locations of a mood circuit in order to determine a mood state of the patient. A relationship (e.g., a ratio) between frequency band characteristics of the monitored brain signals may be indicative of a particular mood state. In some examples, therapy parameter values that define the therapy delivered to the patient may be selected to maintain a target relationship (e.g., a target ratio) between the frequency band characteristics of the brain signals monitored within the mood circuit. In addition, in some examples, therapy delivery to the patient may be controlled based on the frequency band characteristics of brain signals sensed at different portions of the mood circuit.

Abstract: Stuttering-treatment techniques using neural stimulation and/or drug delivery. One or more electrodes and/or a catheter are implanted adjacent to sites in the brain. A signal generator and the electrode deliver stimulation to a first site. A pump and the catheter deliver one or more therapeutic drugs to a second site. The first and second sites could be: the supplementary motor area, the centromedian circuit, the dorsomedial nuclei, the lateral prefrontal circuit, or other paramedian thalamic and midbrain nuclei. The stuttering treatment could be performed via periodic transcranial magnetic stimulation. A sensor, located near the patient's vocal folds, can be used for generating a signal responsive to activity of the patient's speech-producing muscles. A controller adjusts one or more stimulation parameters in response to the signal from the sensor.

Abstract: A therapy system for managing a psychiatric disorder of the patient may be controlled based on a patient mood state. Therapy may be delivered to a patient according to a therapy program, and a physiological parameter of the patient may be monitored during or after therapy delivery. The patient mood state may be determined based on the monitored physiological parameter, and the therapy delivery may be controlled based on the determined mood state. In some embodiments, the therapy delivery is stopped prior to determining the patient mood state and the therapy delivery is restarted upon detecting a negative mood state. In other embodiments, therapy delivery is delivered until a positive mood state is detected, at which point the therapy delivery may be stopped.

Abstract: A characteristic of a washout period following the delivery of therapy to a patient according to a therapy program may be determined based on a physiological parameter of the patient. A washout period includes the period of time during which a carryover effect from the therapy dissipates. The washout period characteristic may include, for example, a duration of the washout period, an amplitude or a trend in a physiological signal during the washout period or a power level or a ratio of power levels in frequency bands of the physiological signal. In some embodiments, washout period characteristics associated with a plurality of therapy programs may be used to compare the programs. In other embodiments, a washout period characteristic may be used to determine a mood state of the patient and, in some cases, modify a therapy program. Monitoring a washout period may also be useful for timing therapy program trials.

Abstract: A characteristic of a washout period following the delivery of therapy to a patient according to a therapy program may be determined based on a physiological parameter of the patient. A washout period includes the period of time during which a carryover effect from the therapy delivery dissipates. Monitoring a washout period may be useful for timing the delivery of therapy according to different therapy programs during a therapy evaluation period. For example, at least one physiological signal of the patient may be monitored to automatically determine when a washout period has ended, e.g., when stimulation and carryover effects of therapy delivery according to a first therapy program have substantially dissipated, in order to determine when therapy delivery according to a second therapy program can be initiated.