Online research in philosophy

The advent of functional brain imaging has revolutionized the ability to understand the biological mechanisms underlying decision-making. Although it has been amply demonstrated that assumptions of rationality often break down in experimental games, there has not been an overarching theory of why this happens. I describe recent advances in functional brain imaging and suggest a framework for considering the function of the human reward system as a discrete agent.

Cognitive neuroscientists use functional magnetic resonance imaging (fMRI) to measure properties of a participant’s brain during a cognitive task. These imaging results are transformed into compelling pictures of brain activity using statistical models. I will argue that, for a broad class of experiments, neuroimaging experts have a tendency to over‐interpret the functional significance of their data. This over‐interpretation appears to follow from contentious theoretical assumptions about the mind‐brain connection, and from a propensity to conflate the anatomical location of a statistically‐significant (...) correlation with knowledge of the mechanistic functioning at that location. (shrink)

Functional magnetic resonance imaging (or fMRI)1 is widely used to support hypotheses about brain function. Many find the images produced from fMRI data to be especially compelling evidence for scientific hypotheses [McCabe and Castel, 2008]. There are many problems with all of this; I want to start with two of them, and argue that they get us closer to an under-appreciated worry about many imaging experiments.

Good research requires, among other virtues,(i) methods that yield stable experimentalobservations without arbitrary (post hoc)assumptions, (ii) logical interpretations ofthe sources of observations, and (iii) soundinferences to general causal mechanismsexplaining experimental results by placing themin larger explanatory contexts. In TheNew Phrenology , William Uttal examines theresearch tradition of localization, and findsit deficient in all three virtues, whetherbased on lesion studies or on new technologiesfor functional brain imaging. In this paper Iconsider just the arguments concerning brainimaging, especially functional MagneticResonance Imaging. I think (...) that Uttal is tooharsh in his methodological critique, butcorrect in his assessment of the conceptuallimitations of localist evidence. I proposeinstead a data-driven test for assessingrelative modularity in brain images, and showits use in a secondary analysis of fMRI datafrom the National fMRI Data Center(www.fmridc.org). Although the analysis is alimited pilot study, it offers additionalempirical challenge to localism. (shrink)

Money is a specifically human incentive. However, functional imaging techniques bring striking evidence that neural circuits pertaining to more “natural” addictive and rewarding processes are involved in response to monetary reward. Main results are evoked here, with specific brain responses demonstrated along the different stages of the process. (Published Online April 5 2006).

aFunctional Imaging Laboratory, Wellcome Department of Imaging Neuroscience, University College London, 12 Queen Square, London WC1N 3BG, UK bDepartment of Experimental Psychology, University of Oxford, UK cOxford Centre for Functional Magnetic Resonance Imaging of the Brain, UK dDepartment of Psychiatry and Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK..