NIRS hyperscanning data analysis (3) quality check

1 min read

NIRS hyperscanning data analysis (1)
NIRS hyperscanning data analysis (2)
NIRS hyperscanning data analysis (3)
NIRS hyperscanning data analysis (4)

Data quality check

1. Behavior data

To identify behavior abnormalities, we need to plot the behavior data for each individual subject. In this case, we plotted the reaction time vs trial. An example is shown below. It apparent that subject 2 (red) did something strange in trial 20.

behavior data (reaction time)
behavior data (reaction time)

We can also plot the difference of reaction time and the threshold to win. Obviously they only win 1 trial and this is unusual.

Reaction time different and threshold
Reaction time different and threshold

We can also find the mean, min and max of the reaction times. Below is the script:

figure;plot([1:40],subjectData.reaction1,'s-')
hold on;plot([1:40],subjectData.reaction2,'s-r')

figure('color','w');plot([1:40],abs(subjectData.reaction1-subjectData.reaction2),'s-k')
hold on;plot([1:40],subjectData.winthreshold,'s-m')
legend({'reaction time difference','threshold'})
xlabel('trial');ylabel('second')

winNum = sum((subjectData.winthreshold - abs(subjectData.reaction1-subjectData.reaction2))>0);
disp('winning trials = ')
disp(winNum)

disp(length(subjectData.eventwarning))

disp(mean(subjectData.reaction1))
disp(max(subjectData.reaction1))
disp(min(subjectData.reaction1))

disp(mean(subjectData.reaction2))
disp(max(subjectData.reaction2))
disp(min(subjectData.reaction2))

2. NIRS data

The 1st way to identify abnormalities in NIRS data is to plot all channel’s time series in one figure, like the figure below. In the following figure, the time series for each channel is plotted and aligned vertically. It’s easy to identify that the green channel (channel #44) has much more noise than others.

NIRS time series

Another way is to use wavelet transform. If the NIRS signal was acquired well, then the heart beating signal should be captured, leaving a bright brand in the frequency ~1Hz in the wavelet transform plot, just like the left plot in the figure below (the band close to period 8). If there is no such band, it does not necessarily mean the signal is trash, but you need to be cautious.

NIRS wavelet
NIRS wavelet

 

The third way is to check the correlation between hbo and hbr. They are supposed to have negative correlation. If not, or if they have perfect negative correlation (-1), then they might contain too much noise. We have a separate article on this method. Please check out https://www.alivelearn.net/?p=1767

[hbo,hbr,mark]=readHitachData('SA06_MES_Probe1.csv');

figure;plotTraces(hbr,1:52,mark)

figure;wt(hbo(:,1))

for ii=1:52; wt(hbo(:,ii)); pause; end

[badchannels] = checkDataQuality(hbo,hbr);

3. Digitizer data

You want to make sure the measure digitizer data is reasonable by looking at the probe positions in a 3D space.

Digitizer data
Digitizer data
pos_data=readPosFile('0001.pos');
figure;plot3(pos_data(:,1),pos_data(:,2),pos_data(:,3),'o');axis equal;



写作助手,把中式英语变成专业英文


Want to receive new post notification? 有新文章通知我

第六十二期fNIRS Journal Club通知2025/5/17, 10am 李杨卓博士

该文章的声音简介(中文版): 该文章的声音简介(英文版): 说服是促进信息传播、人类社会发展最有效的形式之一。日常生活中说服和被说服无处不在,是什么人际神经通路决定了自然二元说服情境中,说服信息的成功
Wanling Zhu
4 sec read

第六十一期fNIRS Journal Club视频 冯小丹

Youtube: https://youtu.be/eyC7K9lxz1s 优酷:https://v.youku.com/video?vid=XNjQ3NDc1MTUwOA%3D%3D 无论是对人类个
Wanling Zhu
15 sec read

第六十一期fNIRS Journal Club通知2025/4/12, 10am 冯小丹

该文章的声音简介(中文版): 该文章的声音简介(英文版): 无论是对人类个体的认知能力发展还是对整个社会的文明演进来说,课堂教学都发挥着不可替代的独特作用。正如著名教育思想家夸美纽斯 (John Am
Wanling Zhu
10 sec read

Leave a Reply

Your email address will not be published. Required fields are marked *