Toolkit for Oscillatory Real-Time Tracking and Estimation (TORTE)

Type: Software,

Keywords: Local field potentials (LFP), Oscillations, Phase relation, Phase estimation, Phase-locking, Autoregressive Model, Open Ephys, Closed-loop stimulation

Open source tools for precise phase-locked neuroscience

Please note this tool was previously referred to as “Phase Calculator Plugin”, which is one component of the Toolkit for Oscillatory Real-Time Tracking and Estimation (TORTE).

We have built a set of open-source tools for precisely locking experimental perturbations (optical/electrical/magnetic stimulation, behavioral triggering, etc.) to the phase of ongoing LFP oscillations (probably could be used with anything that has an oscillation, e.g. whisking). They are substantially more accurate than anything in the published literature and have been adapted to work with both human and animal experimental rigs. The target use case is understanding the role of oscillatory phase in cognition, e.g. altering phase relations between structures by timed perturbation.

*Examples of recent projects include:
– Technologies that lock electrical stimulation to the peaks and troughs of brain oscillations, allowing us to control how those oscillations synchronize (or fall out of sync) between brain regions. This oscillatory coherence is believed to be the basic of brain network communication, and controlling it may be a path to restoring circuit function.
– Measuring and modeling how existing clinical stimulation changes ongoing neural firing. From those models, we hope to design rational and theory-informed algorithms that will (A) let us drive brain networks to any desired state and (B) ensure that we are creating the specific patterns that matter most for clinical symptom relief.
– Testing novel neurostimulation designs in human populations, including: psychiatric patients in formal clinical trials, epilepsy patients with large-scale brain monitoring montages, movement disorders patients undergoing deep brain stimulation, and healthy volunteers.

– Enhancing connectivity between brain regions involved in memory, to improve memory function after brain injury.
– Disrupting hyper-connected circuits involved in compulsive and addictive behavior.
– Increasing “”top down”” control from prefrontal cortex to structures involved in mood and emotion, potentially improving individual emotion regulation.

Rat, human, monkey

*Open source.*
Better accuracy than other published methods.
Written in C++ for high speed/low latency closed loop applications.
Part of a large, well-supported infrastructure (Open Ephys) offering compatibility with a wide range of recording and stimulating technologies.

Specific to the Open Ephys architecture. Can be made compatible with other manufacturers (we support Neuralynx and Alpha-Omega; Blackrock is possible) but would require writing new code.

Blackwood, E., Lo, M., Widge, A. S. (2018). Continuous phase estimation for phase-locked neural stimulation using an autoregressive model for signal prediction. 40th International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), Honolulu, HI, 4736-4739. doi: 10.1109/EMBC.2018.8513232


Alik Widge, Assistant Professor


University of Minnesota