Original Research Article
High-frequency oscillations in distributed neural networks reveal the dynamics of human decision making
1 Biomagnetic Imaging Lab, Department of Radiology, University of California San Francisco (UCSF), USA
2 Department of Neurology, Department of Neurology, University of Berne, Switzerland
3 Joint Graduate Group in Bioengineering, University of California, San Francisco, and University of California Berkeley, USA
2 Department of Neurology, Department of Neurology, University of Berne, Switzerland
3 Joint Graduate Group in Bioengineering, University of California, San Francisco, and University of California Berkeley, USA
We examine the relative timing of numerous brain regions involved in human decisions that are based on external criteria, learned information, personal preferences, or unconstrained internal considerations. Using magnetoencephalography (MEG) and advanced signal analysis techniques, we were able to non-invasively reconstruct oscillations of distributed neural networks in the high-gamma frequency band (60–150 Hz). The time course of the observed neural activity suggested that two-alternative forced choice tasks are processed in four overlapping stages: processing of sensory input, option evaluation, intention formation, and action execution. Visual areas are activated fi rst, and show recurring activations throughout the entire decision process. The temporo-occipital junction and the intraparietal sulcus are active during evaluation of external values of the options, 250–500 ms after stimulus presentation. Simultaneously, personal preference is mediated by cortical midline structures. Subsequently, the posterior parietal and superior occipital cortices appear to encode intention, with different subregions being responsible for different types of choice. The cerebellum and inferior parietal cortex are recruited for internal generation of decisions and actions, when all options have the same value. Action execution was accompanied by activation peaks in the contralateral motor cortex. These results suggest that high-gamma oscillations as recorded by MEG allow a reliable reconstruction of decision processes with excellent spatiotemporal resolution.
Keywords: decision making, choice, magnetoencephalography, time, high-gamma frequency band, source localization, adaptive spatial filter
Copyright: © 2008 Guggisberg, Dalal, Findlay and Nagarajan. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Adrian G. Guggisberg, Biomagnetic Imaging Lab, Department of Radiology, University of California San Francisco (UCSF), 513 Parnassus Avenue S-362, San Francisco, CA 94143-0628, USA; Department of Neurology, University of Berne, Inselspital, 3010 Bern, Switzerland. e-mail: aguggis@gmail.com
Citation: Guggisberg AG, Dalal SS, Findlay AM and Nagarajan SS (2008) High-frequency oscillations in distributed neural networks reveal the dynamics of human decision making. Front. Hum. Neurosci. (2007) 1:14. doi:10.3389/neuro.09.014.2007
Received: 15 October 2007; paper pending published: 28 November 2007; accepted: 09 January 2008; published online: 28 March 2008.
Edited by:
Robert T. Knight, University of California Berkeley, USA
Reviewed by:
Francisco Barcelo, University of Illes Balears, Spain
Olivier Bertrand, INSERM, France; Lyon I university, France
Olivier Bertrand, INSERM, France; Lyon I university, France
*Correspondence: Adrian G. Guggisberg, Biomagnetic Imaging Lab, Department of Radiology, University of California San Francisco (UCSF), 513 Parnassus Avenue S-362, San Francisco, CA 94143-0628, USA; Department of Neurology, University of Berne, Inselspital, 3010 Bern, Switzerland. e-mail: aguggis@gmail.com


