Kernel alignment for identifying objective criteria from brain MEG recordings in schizophrenia

Abstract The current wide access to data from different neuroimaging techniques has permitted to obtain data to explore the possibility of finding objective criteria that can be used for diagnostic purposes. In order to decide which features of the data are relevant for the diagnostic task, we present in this paper a simple method for feature selection based on kernel alignment with the ideal kernel in support vector machines (SVM). The method presented shows state-of-the-art performance while being more efficient than other methods for feature selection in SVM. It is also less prone to overfitting due to the properties of the alignment measure. All these abilities are essential in neuroimaging study, where the number of features representing recordings is usually very large compared with the number of recordings. The method has been applied to a dataset in order to determine objective criteria for the diagnosis of schizophrenia. The dataset analyzed has been obtained from multichannel magnetoencephalogram (MEG) recordings, corresponding to the recordings during the performance of a mismatch negativity (MMN) auditory task by a set of schizophrenia patients and a control group. All signal frequency bands are analyzed (from δ (1–4 Hz) to high frequency γ (60–200 Hz)) and the signal correlations among the different sensors for these frequencies are used as features.

[1]  W. Singer,et al.  Progress in Biophysics and Molecular Biology , 1965 .

[2]  M. E. Spencer,et al.  A Study of Dipole Localization Accuracy for MEG and EEG using a Human Skull Phantom , 1998, NeuroImage.

[3]  Aixia Guo,et al.  Gene Selection for Cancer Classification using Support Vector Machines , 2014 .

[4]  R. C. Oldfield The assessment and analysis of handedness: the Edinburgh inventory. , 1971, Neuropsychologia.

[5]  Jason Weston,et al.  Gene Selection for Cancer Classification using Support Vector Machines , 2002, Machine Learning.

[6]  Fikri Goksu,et al.  Selection of spectro-temporal patterns in multichannel MEG with support vector machines for schizophrenia classification , 2008, 2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[7]  Chih-Jen Lin,et al.  LIBSVM: A library for support vector machines , 2011, TIST.

[8]  Thorsten Joachims,et al.  Text Categorization with Support Vector Machines: Learning with Many Relevant Features , 1998, ECML.

[9]  N. Cristianini,et al.  On Kernel-Target Alignment , 2001, NIPS.

[10]  Roberto Hornero,et al.  Changes in the MEG background activity in patients with positive symptoms of schizophrenia: spectral analysis and impact of age , 2013, Physiological measurement.

[11]  Nello Cristianini,et al.  On the Extensions of Kernel Alignment , 2002 .

[12]  A. Aboraya,et al.  The Reliability of Psychiatric Diagnosis Revisited: The Clinician's Guide to Improve the Reliability of Psychiatric Diagnosis. , 2006, Psychiatry (Edgmont (Pa. : Township)).

[13]  M. Stephane,et al.  Schizophrenia Classification using Working Memory MEG ERD/ERS Patterns , 2007, 2007 3rd International IEEE/EMBS Conference on Neural Engineering.

[14]  Sayan Mukherjee,et al.  Feature Selection for SVMs , 2000, NIPS.

[15]  Nello Cristianini,et al.  Learning the Kernel Matrix with Semidefinite Programming , 2002, J. Mach. Learn. Res..

[16]  P. Nunez,et al.  EEG and MEG coherence: Measures of functional connectivity at distinct spatial scales of neocortical dynamics , 2007, Journal of Neuroscience Methods.

[17]  Michael F. Green,et al.  Diagnosis of schizophrenia: Consistency across information sources and stability of the condition , 2012, Schizophrenia Research.

[18]  Nello Cristianini,et al.  Kernel Methods for Pattern Analysis , 2003, ICTAI.

[19]  S. Nagarajan,et al.  Cognitive Impairments in Schizophrenia as Assessed Through Activation and Connectivity Measures of Magnetoencephalography (MEG) Data , 2009, Front. Hum. Neurosci..

[20]  A. Georgopoulos,et al.  Synchronous neural interactions assessed by magnetoencephalography: a functional biomarker for brain disorders , 2007, Journal of neural engineering.

[21]  M. E. Spencer,et al.  A Study of Dipole Localization Accuracy for MEG and EEG using a Human Skull Phantom , 1998, NeuroImage.

[22]  Ahmed H. Tewfik,et al.  Classification of schizophrenia with spectro-temporo-spatial MEG patterns in working memory , 2009, Clinical Neurophysiology.

[23]  Rajesh P. N. Rao,et al.  Towards adaptive classification for BCI , 2006, Journal of neural engineering.

[24]  Winfried Schlee,et al.  Top-Down Modulation of the Auditory Steady-State Response in a Task-Switch Paradigm , 2008, Front. Hum. Neurosci..

[25]  Gavin C. Cawley,et al.  Manipulation of prior probabilities in support vector classification , 2001, IJCNN'01. International Joint Conference on Neural Networks. Proceedings (Cat. No.01CH37222).