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Band Pass filter Design

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It is designed by giving higher cut of frequency and lower cut of frequencies. We record EEG signal externally by using Electrodes. Because of that Skin noise, skull noise, disturbance noise, power line noise etc noise present in EEG signal. For removing the higher cut off and lower cut of frequency from the signal band pass filter is used. We want the signal frequency up to 30 Hz because the beta band frequencies is up to that frequency. Design the Band pass Butterworth filter in the matlab by using the code Algorithm: i) First take eeg input data ii) Pot that data iii) Mention the sampling frequency iv) Calculate the normalize frequency by using formula fnormal = cut of frequency (Fs/2) v) Then design the butter of the filter in that we put the order of filter, normalize frequency , curve type, for this we take two vectors. vi) Then filter the data using Filtfilt . it performs zero-phase digital filtering by processing t...
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Geography of Thoughts

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The cerebral cortex is split into two hemispheres that often have very different functions. For instance, most language functions lie primarily in the left hemisphere, while the right hemisphere controls many abstract and spatial reasoning skills. Also, most motor and sensory signals to and from the brain cross hemispheres, meaning that the right brain senses and controls the left side of the body and vice versa. The brain can be further divided into separate regions specialized for different functions. For example, occipital regions at the very back of the head are largely devoted to processing of visual information. Areas in the temporal regions, roughly along the sides and lower areas of the cortex are involved in memory, pattern matching, and language processing and auditory processing. Still other areas of the cortex are devoted to diverse functions such as spatial representation and processing, attention orienting, arithmetic, voluntary muscle movement, planning, reas...
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Electrode distribution

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     The standard EEG electrodes naming and position on the scalp are according to the international 10-20 electrode system ( Jasper 1958 ). The system ensures that different laboratories share the same names over electrode positioning. It is based on arcs dividing the scalp in an array, using the Nasion and Inion as longitudinal reference points (i.e. front and back respectively) and the left and right Pre-Auricular points as lateral reference points ( Figure a .). The intersection between the longitudinal line and the lateral is called the Vertex, and at this point it is located over the center. The 10-20 system identify each point using each lobe (Frontal-F, Temporal-T, Central-C, Parietal-P and Occipital-O) and each hemisphere (Left-Odd, Right-Even numbers and z or zero over the midline) as a marking. An extension to this configuration is using 70 electrodes ( Figure b.), subdividing in between the 10-20 arcs (using the combinations of the letters ...
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