Editing Talk:1453: fMRI

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..."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"
 
..."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"
Actually, task activation is generally compared to some other control task or condition, rather than resting state, especially for a short-term memory study such as that referenced in the comic. For example some other task with matched stimulus presentation and response demands (i.e. press a button), but without any memory load. And if rest were used as the implicit baseline, it is extremely unlikely any actual subtraction would be done--rather the so-called resting state would be the implicit baseline state of a multiple regression, in which the task-related predictor variables are convolved with a canonical hemodynamic response function. {{unsigned ip|108.162.219.118}} [[Special:Contributions/108.162.219.118|108.162.219.118]] 18:57, 1 December 2014 (UTC)
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Actually, task activation is generally compared to some other control task or condition, rather than resting state, especially for a short-term memory study such as that referenced in the comic. For example some other task with matched stimulus presentation and response demands (i.e. press a button), but without any memory load. And if rest were used as the implicit baseline, it is extremely unlikely any actual subtraction would be done--rather the so-called resting state would be the implicit baseline state of a multiple regression, in which the task-related predictor variables are convolved with a canonical hemodynamic response function. {{unsigned ip|108.162.219.118}}
 
 
Also, the concern with unremoved piercings would not be that they could be ripped off during scanning. A participant or patient would not be allowed in the MR room with a dangerous (i.e. large, ferrous metal) piercing, and if somehow one were it would be noticed prior to the initiation of any functional scans (the magnet is always on, so it would be ripped off or otherwise respond to the magnetic field while the participant was being positioned in the scanner bore). Rather, the concern here would be about the piercings heating up during scanning and potentially burning the participant, or potentially causing magnetic susceptibility artifacts in the acquired images (particularly for facial piercings). As precaution it is common to warn participants with unremoved piercings to be attentive to any heating sensation around their piercings and to notify MR technologists immediately if any heating occurs. [[Special:Contributions/108.162.219.118|108.162.219.118]] 18:57, 1 December 2014 (UTC)
 
 
 
When I remove jewelry, my main worry is that it will get stolen. {{unsigned ip|199.27.133.94}}
 

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