Performance monitoring in obsessive–compulsive disorder: A temporo-spatial principal component analysis

Abstract

Hyperactive performance monitoring is a robust finding in obsessive–compulsive disorder (OCD). Patients show increased amplitudes of the error-related negativity (ERN) and correct-related negativity (CRN). Recently, two temporo-spatial factors were shown to contribute to both ERPs in healthy individuals. In the present study, it was investigated whether the factor structure underlying ERN and CRN is similar in OCD and which factors differ between groups. A principal component analysis (PCA) was employed to investigate the temporo-spatial factor structure of ERN and CRN. Twenty-six OCD patients and 26 healthy controls conducted a flanker task. EEG data were analyzed as conventional ERP components and as factor scores derived from temporo-spatial PCA. ERP results showed expected increases in ERN and CRN amplitudes in OCD patients. For both groups, the PCA confirmed the assumed factor structure of a central and a fronto-parietal factor contributing to ERN and CRN. Factor scores of both factors were differently affected by response correctness in OCD. Alterations in factor scores indicate increased activity in both an outcome-independent monitoring process and an error-sensitive process, contributing to overactive performance monitoring in OCD.

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Notes

  1. 1.

    This baseline was used on the basis of similar baseline intervals in earlier studies (Hajcak, McDonald, & Simons, 2004; Larson, Fair, Good, & Baldwin, 2010; Riesel et al., 2011; Ruchsow et al., 2005) and because it aligns preresponse activity between groups. However, the baseline interval already includes the peak that is preceding the ERN and CRN.

  2. 2.

    ERP effects were also analyzed as mean amplitudes (0–100 ms postresponse), and results are in accordance with results from peak analysis. Significant main effects were found for response type, F(1, 50) = 101.97, p < .001, η 2 = .671, and electrode, F(2, 100) = 113.41, p < .001, η 2 = .694, ε = .701, as well as group, F(1, 50) = 7.78, p = .007, η 2 = .135. Interactions were found significant for response type with electrode, F(2, 100) = 56.13, p < .001, η 2 = .529, ε = .691, and there was a trend for response type and group, F(1, 50) = 3.12, p = .084, η 2 = .059.

  3. 3.

    Since this temporo-spatial factor comprised a frontal negativity and parietal positivity, ERP mean amplitudes of ERN and CRN (0–100 ms) were further analyzed by including frontal as well as parietal electrodes. A repeated measures ANOVA was conducted with the factors of group, response type, and caudality (frontal: Fz, FCz; parietal: Cz, CPz). Results indicate significant main effects of response type, F(1, 50) = 79.98, p < .001, η 2 = .615, caudality, F(1, 50) = 245.67, p < .001, η 2 = .831, and group, F(1, 50) = 4.70, p = .035, η 2 = .086. Significant interactions were present for response type with group, F(1, 50) = 4.54, p = .038, η 2 = .083, as well as caudality with group, F(1, 50) = 5.39, p = .024, η 2 = .097, and response type with caudality, F(1, 50) = 18.98, p < .001, η 2 = .275, while the three-way interaction was not significant, F(1, 50) = 0.001, p = .970, η 2 = .000. The response type effect indicates that amplitudes were more negative for errors than for correct responses, while the main effect of caudality indicated that amplitudes were negative at frontal electrodes and positive at parietal electrodes. The interaction of response type and caudality further showed that the difference between errors and correct responses was larger at frontal electrode sites (mean difference: 3.47 μV), as compared with parietal electrode sites (mean difference: 1.5 μV), although it was, in both cases, significant (both ps < .001). The group main effect suggests more negative amplitudes in the OCD group than in the HC group. The interaction of group with caudality indicates that groups differed significantly at frontal electrode sites (p = .006), but not at parietal electrode sites (p = .802).

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Acknowledgments

This work was supported by the German Research Foundation (DFG; EN 906/1-1).

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Klawohn, J., Riesel, A., Grützmann, R. et al. Performance monitoring in obsessive–compulsive disorder: A temporo-spatial principal component analysis. Cogn Affect Behav Neurosci 14, 983–995 (2014). https://doi.org/10.3758/s13415-014-0248-0

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Keywords

  • OCD
  • Error-related negativity
  • Correct-related negativity
  • Performance monitoring
  • EEG
  • PCA