FMRI

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Remarkably precise areas of cortex are often hypothesised to be associated with extremely complex processes and very subtle distinctions. Two examples of cartoons are shown here, one requires a theory of mind the other does not. From Gallagher et al (2000)[1].
Many techniques in neuroscience require the observer to maintain their head position with respect to the visual stimulus and often fixate on a point, too. fMRI is a good example. This stability is critical for studying certain cortical responses such as the retinotopic arrangement of visual areas and other factors that are relevant within a single loop of the helix. But fMRI is used for a much wider range of experiments, ones that involve many loops, for example, scanning the cortical responses of people looking at cartoons that do or do not require a theory of mind in order to understand the joke[1]. The paths through sensory+motivational space are presumably quite different in these two cases, but the trace left behind, in terms of different activity in the cortex, blurred over a long time course as fMRI does, may be quite slight and not the best way of describing the difference between the responses to the two types of cartoon. According to a perspective like this, there is no theory of mind 'portion' of the cortex or even theory of mind ‘network’ (a currently popular idea). Instead, the pattern of paths through sensory+motivational space is quite different for someone who views a cartoon and has a theory of mind compared to someone who does not. The idea that every capacity must have a separate ‘area’ or ‘network’ in the cortex belongs to a quite different conception of the brain.

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References

  1. 1.0 1.1 Gallagher, H. L., Happé, F., Brunswick, N., Fletcher, P. C., Frith, U., & Frith, C. D. (2000). Reading the mind in cartoons and stories: an fMRI study of ‘theory of mind’in verbal and nonverbal tasks. Neuropsychologia, 38(1), 11-21.