In a 2009 study, scientists there used fMRI (Functional MRI) imaging to measure brain activity in regions of emotional processing in the brain before and after injecting Botox to suppress smiling muscles.

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The researchers used fMRI (functional magnetic resonance imaging) scans to monitor brain activity in 15 people with autistic spectrum disorders and 15 without.

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The hype has increased in the last few decades since functional neuro-imaging has enabled scientists to observe directly the activity in the brains of conscious subjects exposed to certain stimuli or engaging in different tasks.

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It does not measure the actual activity, but can provide clues that some areas are still functional.

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And secondly we are looking at functional connectivity - how strongly two brain regions are linked across time and activity.

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Using a technique called functional magnetic resonance imaging (fMRI), the researchers were able to record the brain's activity in response to internal and external stimuli such as eating and drinking.

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