Patients with bipolar disorder show altered gaze processing on EEG recordings taken during working memory exercises, new study results suggest.
The study, led by Cristina Berchio of the department of basic neurosciences at the University of Geneva, recruited 19 euthymic patients with bipolar I or II from the Mood Disorders Unit at the University Hospital of Geneva and 19 controls matched for age, gender, education level, and handedness. While undergoing high-density EEG recording, participants performed a two-back working memory exercise that involved neutral faces with either direct or averted gazes. The study was published in NeuroImage: Clinical.
; both of those functions are thought to be impaired in patients with bipolar disorder. They suggested that this might reflect early-life dysfunctional parental-infant gaze experiences that could affect how those patients with bipolar disorder learned emotion-regulation strategies. “In this sense, our early gaze experiences might also be considered an environmental risk factor, that might remain as a vulnerability trait in [bipolar patients],” they wrote.
Limitations of the study include the working memory exercise’s design, which could have led to misleading anticipatory effects. The small sample size is another limitation that affected the ability to perform certain analyses. The surface nature of EEG also limited evaluation of deeper brain structures that might have proved salient to this exercise.
The study was supported by several entities, including the Swiss National Center of Competence in Research. The authors declared no conflicts of interest.
SOURCE: Berchio C et al. NeuroImage Clin. 2019. doi: 10.1016/j.nicl.2017.09.006.