A magnetoencephalography study of choice bias
permalinkExperimental Brain Research - 2010-04-01Hedgcock WM, Crowe D, Leuthold A, Georgopoulos AP10.1007/s00221-009-2117-6Many factors can influence, or bias, human decision making. A considerable amount of research has investigated the neural correlates of such biases, mostly correlating hemodynamic responses in brain areas with some aspect of the decision. These studies, typically done using
Functional Magnetic Resonance Imagingor positron emission tomography, have provided useful information about the location of processing in the brain. However, comparatively little research has examined when these processes occur. The present experiment addressed this question by using
Magnetoencephalographyto record brain activity while subjects chose preferred options from decision sets. We found that
MEGsignal deviations for biased decisions occurred as early as 250-750 ms following stimulus onset. Such deviations occurred earliest in sensors over the right anterior cortex. These findings improve our understanding of temporal dynamics of decision biases and suggest ways that existing explanations for this bias could be refined.