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EEG signs of aging and dementia based on free energy principle and Bayesian brain. Aman Bindal Old řich Vyšata. Dementia. Definition Symptoms Spread Economic effects. Dementia Types. Cases in AD. AD Age groups. Cost of Dementia. Recording EEG. Sample Recording.
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EEG signs of aging and dementiabased on free energy principle and Bayesian brain AmanBindal Oldřich Vyšata
Dementia • Definition • Symptoms • Spread • Economic effects
Fourier transform (FT) • Fourier transform expands a time signal x(t) into a sum (or integral for continuous time) of infinite waves • It can be thought of a transform from “time-domain” to “frequency domain”. FT is formally defined by: • Used in many areas because the concept of frequency and periodic signals is shared in many science domains. • When we talk about “Power spectrum” of a signal we mean the amplitude of the Fourier transform Fourier transform FT Inverse Fourier transform IFT
Free Energy Principle? Self-organizing system that is at equilibrium with its environment must minimize its free energy • Concept • Related to Brain and EEG • EEG characteristics of self-organization
Aging and Neuron Loss • Lesser Number of Neurons for electrical activity (Slower EEG) • Decrease in neuron interaction (Perturbations in EEG Synchrony) • Neural activity patterns and dynamics become simpler and more predictable (Entropy)
Parameters • Pearson Correlation Coefficient • Coherence • Mutual Information
Parameters Contd • Coherence in Frequency Domain • Wavelet Coherence • Corr-Entropy Coefficient
Data • Total Recording: 31009 • Unfiltered Recordings: 17722 • 17540 males • 182 females • mean age of 43.2 (SD=11.2) years
Conclusion • Lossof brain’s auto-organization ability of free energy optimization. • Age related cognitive deficit and dementia • Entropy as the best parameter
Future Work • Including more complexity measures as parameters • Calculation of alpha based on Hurst exponent • Probabilistic model for differentiating AD patients.
Thank You Q & A