TABLE 1.
Example of dual detector parameter set from a single patient and hemisphere.
| Setting | Value | Notes |
| Stimulation rate | 130.2 Hz | Stimulation rate |
| Stimulation pulse | 60 μs | Stim pulse width |
| Stimulation contact | +1-case | Monopolar stimulation |
| Shared parameters for both detectors | ||
| Time domain sampling rate | 500 Hz | Sampling rate for time domain data |
| LPF1 | 450 Hz | Embedded low pass filter before amplification |
| LPF2 | 1,700 Hz | Embedded low pass filter after amplification |
| FFT interval | 500 ms | Interval in which FFT is computed |
| FFT size | 1,024 | Number of points for onboard FFT computation |
| Ramp up rate | 0.03 mA/sec | Rate at which stimulation changes from lower to higher amplitudes |
| Ramp down rate | 0.12 mA/sec | Rate at which stimulation changes from higher to lower amplitudes |
| Motor detector | ||
| Sense channel | + 9−8 | MC (motor cortex) |
| Linear detector power band input | 64.45 – 66.41 Hz | Predefined power band for embedded on board power computation |
| Update rate | 60 | Number of FFT intervals averaged in non-moving average, represents 30 s of data. Defines algorithm rate (e.g., algorithm state is determined every 30 s). This is referred to as “detector count” below. |
| Onset | 0 | Number of detector counts must be above threshold to change to state. A value of 0 means that as soon as the threshold is crossed stimulation ramps to the target state. |
| Termination | 4 | Number of detector counts must be below threshold to change to state. Detector value must be below threshold for 2 consecutive minutes (update rate × 4; = 4 min in this case) before it transitions to state. |
| State change blank | 30 | In units of FFT interval. On state change power values are not computed into linear detector for 15 s (FFT interval × 30). |
| Target current state 0 | 3.1 mA | Target stim to ramp to when stimulation is below lower threshold (for the first linear detector- “LD0”) |
| Target current state 1 | HOLD | Target stim to ramp to when stimulation between upper and lower thresholds (for the first linear detector – “LD0”) |
| Target current state 2 | 2.7 mA | Target stim to ramp to when stimulation is above lower threshold (for the first linear detector – “LD0”) |
| Sleep Detector: | ||
| Sense channel | +9−8 | MC (motor cortex) |
| Linear detector power band input | 3.42 – 12.21 Hz | Predefined power band for embedded on board power computation |
| Update rate | 60 | Number of FFT intervals averaged in non-moving average, represents 30 s of data. Defines algorithm rate (e.g., algorithm state is determined every 30 s) |
| Onset | 0 | Number of detector counts must be above threshold to change to state (in “update rate” units). |
| Termination | 10 | Number of detector counts must be below threshold to change to state. Detector value must be below threshold for 5 consecutive minutes (update rate × 10; = 10 min in this case) before it transitions to state. |
| State change blank | 30 | In units of FFT interval. On state change power values are not computed into linear detector for 15 s (FFT interval × 30). |
| Target current state 3 | 2.7 mA | Target stim to ramp to when stimulation is below lower threshold (for the second linear detector – “LD1”) |
| Target current state 4 | 2.7 mA | Target stim to ramp to when stimulation between upper and lower thresholds (for the second linear detector – “LD1”) |
| Target current state 5 | 2.7 mA | Target stim to ramp to when stimulation is above lower threshold (for the second linear detector – “LD1”) |