Department of Psychology, Dalhousie University, Life Sciences Centre, Halifax, Nova Scotia, Canada.
Psychiatry Res. 2010 May 30;182(2):160-4. doi: 10.1016/j.pscychresns.2010.01.005. Epub 2010 Apr 20.
Magnetic resonance imaging (MRI) scans frequently trigger state anxiety in individuals being scanned. It is not known, however, whether levels of MRI-related anxiety change over the course of a single scan or across repeated scanning experiences. Since changes in state anxiety are known to affect regional brain activity in healthy volunteers, systematic changes in levels of MRI-related anxiety could confound findings from neuroimaging studies. We assessed anxiety levels in eleven healthy male volunteers during a control period and during two MRI scanning sessions. Anxiety levels were highest during the first MRI scan, dropping to control levels or below by the second scan. In addition, anxiety fluctuated within scanning sessions, particularly during the first scan, with levels high at the beginning of the session, decreasing during mid-scan and then increasing again toward the end of the session. These results suggest that habituation in an MRI simulator before participating in a neuroimaging study could help to decrease fluctuations in MRI-related anxiety. Moreover, in studies that address several experimental questions within a single scanning session, experimental designs could be adapted to avoid potential confounds from within-scan variation in scanner-related anxiety.
磁共振成像（MRI）扫描常会引发被扫描者的状态焦虑。然而，目前尚不清楚 MRI 相关焦虑水平是否会在单次扫描过程中或在多次扫描经历中发生变化。由于状态焦虑的变化已知会影响健康志愿者的大脑区域活动，因此 MRI 相关焦虑水平的系统性变化可能会使神经影像学研究的结果产生偏差。我们在一项对照期和两次 MRI 扫描期间评估了 11 名健康男性志愿者的焦虑水平。焦虑水平在第一次 MRI 扫描时最高，第二次扫描时降至对照水平或以下。此外，焦虑在扫描期间波动，特别是在第一次扫描期间，在扫描开始时焦虑水平较高，在扫描中期下降，然后在扫描结束时再次升高。这些结果表明，在参加神经影像学研究之前，在 MRI 模拟器中进行习惯化可能有助于减少 MRI 相关焦虑的波动。此外，在单次扫描期间内解决多个实验问题的研究中，可以调整实验设计以避免由于与扫描仪相关的焦虑在扫描期间的变化而产生潜在的混杂因素。
