John Fredy Ochoa Gómez, Ph. D.

e-mail: john.ochoa@udea.edu.co

INTERESTS: Biosignals and Systems, Digital image processing, Processing of biomedical signals, Neuroengineering.

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A review of the current findings in PSEN1 E280A Family using quantitative EEG.


The most common cause of familial early onset AD are the PSEN1 mutations. One of the largest family of carriers of the mutation lives in Antioquia, Colombia. The study of mutation carriers provides a unique opportunity to characterize the preclinical changes and the brain reorganization strategies associated with predisposition to AD. The Electroencephalography (EEG) has an enormous potential to study the neurophysiological changes in neurodegenerative processes with promising clinical applications.

During the 2012 – 2017 period different studies on a large database of high density EEG from PSEN1 E280A carriers were done trying to identify early changes that could be preclinical biomarkers of AD. Although many findings have been reported using nuclear medicine techniques, the use of EEG opens the possibility to obtain markers that could be easily used on a broad population as a first filter before the use of more invasive or expensive techniques.

Univariate and multivariate approaches were done over the data to stablish a baseline of possible easy detectable changes that could be transferred to clinical settings. The current review discuss the findings using spectral analysis, functional connectivity and graph theory.


Spatial filters for the study of neurodegenerative diseases: results and perspectives on PSEN1 E280A Family.


In the current review the results obtained using a workflow based on Independent Component Analysis, introduced to improve the spatial resolution given by EEG, are discussed. The workflow open the possibility of explore reliable neuronal sources among subjects and compare those sources in clinical populations. The comparison of carriers of PSEN1 E280A mutation and non-carriers, show altered brain function even in asymptomatic stage complementing previous findings using functional Magnetic Resonance Imaging or Positron Emission Tomography. Regions, like the Precuneus, can be screened across the neurodegenerative process, offering new potential biomarkers of the Alzheimer’s disease. The multivariate analysis of brain sources show generalized impairment in the brain connectivity for asymptomatic subjects. The results found using the workflow were compared with alternatives approaches of analysis, based on scalp EEG or data obtained through inverse solution methods, corroborating the findings. The neurophysiological correlates found opens the possibility of studying new biomarkers in AD based in EEG. The workflow proposed can be used in other neurodegenerative diseases or other brain mapping problems based in EEG.