Implantable Device Phase-Amplitude Coupling Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring phase-amplitude coupling in brain signals are computationally intensive and typically require external processing, making them impractical for implementation in implantable medical devices.
Innovation Solution
An active implantable medical device is configured to sense brain signals and compute measures of phase-amplitude coupling in real time using a data analyzer that processes electrographic signals to detect features in low and high frequency ranges, and calculates metrics to determine the strength of phase-amplitude coupling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional phase-amplitude coupling measurement methods are used, then measurement precision is improved, but device complexity and computational requirements increase significantly
Solution Approach 1:
The patent segments the brain signal processing into distinct frequency band analyses (theta, alpha, beta, gamma bands) and separates phase extraction from amplitude modulation detection. This segmentation allows the complex phase-amplitude coupling calculation to be broken down into manageable computational steps that can be executed by implantable devices with limited processing power.
Solution Approach 2:
The patent transforms the continuous signal processing problem into discrete parameter measurements by extracting specific features (phase angles, amplitude envelopes) at defined time points. This parameter transformation reduces the computational burden while preserving the essential coupling information, enabling implementation in resource-constrained implantable devices.
2Loss of time
If real-time processing is implemented in implantable devices, then response time is improved, but power consumption and computational resources increase
Solution Approach 1:
The patent implements periodic computation of phase-amplitude coupling metrics at defined intervals rather than continuous calculation. This periodic action allows the device to maintain real-time monitoring capability while reducing average power consumption by processing signals only when necessary, balancing responsiveness with energy conservation in implantable operation.
3Measurement precision
If comprehensive signal processing is performed externally, then measurement precision is improved, but ease of operation and portability worsen
Solution Approach 1:
The patent designs the implantable device to perform multiple functions including signal acquisition, preprocessing, phase-amplitude coupling calculation, and therapeutic stimulation delivery. This multi-functionality integrates what would otherwise require separate external devices, improving portability and ease of operation while maintaining measurement precision through on-device processing capabilities.
Data Source
AI summary
A sensor of an implantable medical device senses electrical activity of the brain. A data analyzer of the device monitors an electrographic signal corresponding to the electrical activity of the sensed brain signal, and processes the brain signal to obtain a measure of phase-amplitude coupling. For a selected portion of the electrographic signal, the data analyzer detects first features and second features of the electrographic signal. The first features represent oscillations in a low frequency range, while the second features represent oscillations in a frequency range higher than the low frequency range. For example, the low frequency range may correspond to theta frequency and the higher frequency range may correspond to gamma frequency. The data analyzer determines a measure of phase-amplitude coupling between oscillations in the low frequency range and oscillations in the higher frequency range based on occurrences of second features which coincide with first features.