Auditory P3a and P3b neural generators in schizophrenia: An adaptive sLORETA P300 localization approach.
The present study investigates the neural substrates underlying cognitive processing in schizophrenia (Sz) patients. To this end, an auditory 3-stimulus oddball paradigm was used to identify P3a and P3b components, elicited by rare-distractor and rare-target tones, respectively. Event-related potentials (ERP) were recorded from 31 Sz patients and 38 healthy controls. The P3a and P3b brain-source generators were identified by time-averaging of low-resolution brain electromagnetic tomography (LORETA) current density images. In contrast with the commonly used fixed window of interest (WOI), we proposed to apply an adaptive WOI, which takes into account subjects' P300 latency variability. Our results showed different P3a and P3b source activation patterns in both groups. P3b sources included frontal, parietal and limbic lobes, whereas P3a response generators were localized over bilateral frontal and superior temporal regions. These areas have been related to the discrimination of auditory stimulus and to the inhibition (P3a) or the initiation (P3b) of motor response in a cognitive task. In addition, differences in source localization between Sz and control groups were observed. Sz patients showed lower P3b source activity in bilateral frontal structures and the cingulate. P3a generators were less widespread for Sz patients than for controls in right superior, medial and middle frontal gyrus. Our findings suggest that target and distractor processing involves distinct attentional subsystems, both being altered in Sz. Hence, the study of neuroelectric brain information can provide further insights to understand cognitive processes and underlying mechanisms in Sz.
Biomedical Engineering Group, E.T.S. Ingenieros de Telecomunicación, Universidad de Valladolid, 47011 Valladolid, Spain. Electronic address: alejandro.bachiller@uva.es.
Alejandro
A
Bachiller
Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), 08028 Barcelona, Spain; CIBER-BBN, Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Spain. Electronic address: sergio.romero-lafuente@upc.edu.
Sergio
S
Romero
Psychiatry Department, Hospital Clínico Universitario, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain; INCYL, Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, 37007 Salamanca, Spain. Electronic address: vmolina@med.uva.es.
Vicente
V
Molina
Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), 08028 Barcelona, Spain; CIBER-BBN, Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Spain. Electronic address: joan.francesc.alonso@upc.edu.
Joan F
JF
Alonso
Department of Automatic Control (ESAII), Biomedical Engineering Research Center (CREB), Universitat Politècnica de Catalunya (UPC), 08028 Barcelona, Spain; CIBER-BBN, Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, Spain. Electronic address: miguel.angel.mananas@upc.edu.
Miguel A
MA
Mañanas
Biomedical Engineering Group, E.T.S. Ingenieros de Telecomunicación, Universidad de Valladolid, 47011 Valladolid, Spain; INCYL, Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, 37007 Salamanca, Spain; IMUVA, Instituto de Investigación en Matemáticas, Universidad de Valladolid, 47011 Valladolid, Spain. Electronic address: jesus.poza@tel.uva.es.
Jesús
J
Poza
Biomedical Engineering Group, E.T.S. Ingenieros de Telecomunicación, Universidad de Valladolid, 47011 Valladolid, Spain; IMUVA, Instituto de Investigación en Matemáticas, Universidad de Valladolid, 47011 Valladolid, Spain. Electronic address: roberto.hornero@tel.uva.es.
Roberto
R
Hornero
D000161:Acoustic Stimulation; D000328:Adult; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D001931:Brain Mapping; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012559:Schizophrenia / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed
Event-related potentials; Loreta; P3a and P3b; Schizophrenia; Source localization; Window of interest