Difference between revisions of "CorTec BIC"

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*Attention
 
*Attention
Please note that this example is only to illustrate how to obtain measurement values. It writes a value to stdout approximately every millisecond (i.e., with the sampling frequency) will cause performance issues on slow machines. For productive use, the measurement data can be passed to another thread for further processing or written to a binary file, instead of being written to stdout.
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Please note that the current implementation writes a value to stdout approximately every millisecond (i.e., with the sampling frequency) will cause performance issues on slow machines. For productive use, the measurement data can be passed to another thread for further processing or written to a binary file, instead of being written to stdout.
  
 
===Doing Stimulation===
 
===Doing Stimulation===

Revision as of 15:28, 26 July 2019

Introduction

CorTec BIC is an application interface (API) in BCI2000 that facilitates with the CorTec hardware device, which is implanted in animals (primarily, pigs) for research and medical purposes. The API enables programmatic access to BIC implants.

Walkthrough: Experimental Steps

The following steps are the primary steps to perform the necessary experiment for medical and research purposes.

Initial Access and Device Discovery

There are several functions in the header file bciapi.h that provide central access to the application interface which helps in creating an implant factory and obtaining some information and details regarding the connected external units and implant devices (device discovery).

Implant Object Creation

This steps involves creation of implant object. During this step, it is assumed that only one external unit is connected and one implant is connected to this external unit. Then this implant object is used to query the temperature and the humidity within the implant's hermetic capsule.

Obtaining Measurement Data

In this step, an Implant listener object is created and registered to an Implant object. Then the measurement is started and one channel is written to standard output.

  • Attention

Please note that the current implementation writes a value to stdout approximately every millisecond (i.e., with the sampling frequency) will cause performance issues on slow machines. For productive use, the measurement data can be passed to another thread for further processing or written to a binary file, instead of being written to stdout.

Doing Stimulation

In this step, electrical stimulation is performed via an implant by first creating a stimulation command that stimulates with a frequency of ~18.5Hz.

Parameters:CorTec BIC Implant

Following is the Parameter Configuration for BIC Implant application interface in BCI2000.

Source Parameters

SourceCh

The total number of digitized and stored channels.

SampleBlockSize

Samples per channel per digitized block. Together with the sampling rate, this parameter determines how often per second data are collected, processed, and feedback is updated. For example, at 500 Hz sampling and a SampleBlockSize of 20, the system (e.g., source signal display, signal processing, and stimulus presentation) will be updated 25 times per second.

SamplingRate

The sample rate of the system. All data is either acquired at 250Hz In case you are experiencing problems by higher sampling rates (e.g., data loss, jerky display, etc.), increase the SampleBlockSize so that you are updating the system less frequently (usually, updating the system 20-30 times per second is sufficient for most applications), and increase Visualize->VisualizeSourceDecimation. This parameter will decrease the number of samples per second that are actually drawn in the Source display.

SourceChOffset

Offset for each channel.

SourceChGain

Gain for each channel.

ChannelNames

Names of each channel.

Filtering Parameters

EnableStimulation

Flag to enable/disable stimulation.

StimulationParameters

Matrix to store parameters defined as follows: StimulatonId, StimulationType (voltage/current),DurationDuration1, amplitude1,DurationDuration2, amplitude2 ...

StimulationTriggers

Matrix to define a trigger for stimulation. Convention: StimulatonId, trigger equation,repeats, anode electrodes, kathode electrodes

StimulationExpression

Expression to start CorTec Stimulation.

AbortExpression

Expression to abort CorTec Stimulation.

EnableCorTecFilter

Flag to enable/disable CorTecFilter.

CheckState

Integer to connect stimulation parameters.

See also

User Reference:Filters, Contributions:ADCs