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Revision as of 00:13, 5 January 2014

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fMRI
They also showed activation in the parts of the brain associated with exposure to dubious study methodology, concern about unremoved piercings, and exasperation with fMRI techs who won't stop talking about Warped Tour.
Title text: They also showed activation in the parts of the brain associated with exposure to dubious study methodology, concern about unremoved piercings, and exasperation with fMRI techs who won't stop talking about Warped Tour.

Explanation

fMRI (Functional Magnetic Resonance Imaging), as the name suggests, is an offshoot of the MRI procedure. It is a technique designed to show brain activity, typically while the subject is performing tasks or responding to stimuli. During the test, the subject is laid in a relatively small cylinder inside a big, very loud, machine producing extremely strong magnetic fields. To prevent damage or injury, the subject must remove all metal objects from their body, including piercings, jewelry, watches etc.

In the tests shown, the brain activity detected is a direct results of the testing environment itself, and has nothing to do with the simple tasks being performed by the subject. During fMRI participants hear loud noises, are confined in a small space (thus the claustrophobia) and have removed their jewelry. The researcher has mistaken these associated brain activities as effects as being caused by performing simple tasks which the participants have been asked to do and not a direct result of the settings of the test. Thus, the memory areas described by Megan are those associated with taking a functional MRI scan, rather than those associated with the "test" supposedly being carried out.

In real experiments, reported activity patterns are always a result of subtracting average brain activity from many samples gathered during task from so called resting-state activity - which is obtained while subjects are not engaged in any task, thus eliminating the effect the setting has on brain activity. Apparently, the researcher in the comic has failed to account for that in the analysis of the data.

It appears that Randall makes fun of the overly confident, sweeping statements made by some fMRI researchers, often in the press. In reality the technique requires that the researcher account for several possible sources of errors by, among others, performing proper statistical analyses, multiple comparisons and using proper control groups. These are usually the reasons for fMRI criticism. See the link for further information as well as an anecdote involving a dead salmon showing brain activity.

The title text continues directly with this theme by saying that the subjects also showed activation in the parts of the brain associated with exposure to dubious study methodology. It then continues with the jewelry issue, now especially the concern about unremoved piercings. In the worst case these could be ripped off by the strong magnetic field. So it could be of some concern - especially when you take into consideration some of the places people may have piercings that is not obvious to the MRI personnel! The final remark about activation regards exasperation with fMRI techs who won't stop talking about Warped Tour. "Warped Tour" refers to a traveling music festival that has been going since 2009, originally as a punk rock festival, but now with a more diverse set of music. Due to the nature of Mosh Pits, the loud, cacophonous music, the facial jewelry of concert-goers and the tight quarters of the pit make it similar in description to an MRI.

Transcript

[Megan talking to an unseen audience in front of an fMRI brain scan]
Megan: Our fMRI study found that subjects performing simple memory tasks showed activity in the parts of the brain associated with loud noises, claustrophobia, and the removal of jewelry.

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