Biological signal analysis

Subject description

Signal transduced from living organisms are reporting processes at the molecular, cell, organ, or systemic level of organisation. Biological signals range from recordings of speech, the electrocardiogram (ECG), the electroencephalogram (EEG), electroretinogram (ERG), electrophysiological recordings on single cells, etc. In many cases we record a combination of signals, e.g. fluorescence signal as a reporter of calcium level in the cell, together with the signal of the plasma membrane current. Similarly, we record signals of a polygraph (lie detector) or polysomnograph for sleep studies. Biological signals are and additive combination of signal and noise.

A brief introduction to signal processing in Octave or Matlab will be given.

Practical application of the signal processing will be studied. We will use analysis approaches of time dependent changes of biological measurements. We will use filtering, fitting of functions, averaging. An example of study of a line profile of fluorescent intensities will be presented. The image noise often results in scattered line profiles. Filtering of the signal results in reduced spatial resolution of the processed data. To avoid reducing the spatial resolution we will apply averaging of neighbouring pixel values. In this practical example the discrete Fourier transform (DFT) will be computed with a fast Fourier transform (FFT) algorithm.

The subject is taught in programs

Objectives and competences

Acquiring of basic skills on data acquisition, analogue to digital conversion, processing, analysis and interpretation of results.

– Data acquisition,

– Noise evaluation and analysis

– Signal averaging, filtering, correlation,

– Measurements of features in the signal

– Real and Complex Fourier Series, Fast Fourier transform, Bode plot

Teaching and learning methods

Lectures, consultations, practical demonstrations, seminars, individual project.

Expected study results

Knowledge and understanding:


– practical knowledge to solve signal processing tasks using computer tools.

– understanding basics of biological signals

– choosing of appropriate methodology to process and analyse signals.

Basic sources and literature

R.B. Northrop:  Signals and Systems Analysis In Biomedical Engineering, 2. ed., CRC press (2009)


Izbrani članki iz revije Biomedical Signal Processing and Control, Elsevier

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