Unconscious cognitive dysfunction in emotion dysregulation and psychopathology of panic disorder: evidence from the late positive potential
To date, only two research groups have used functional MRI to investigate the neural basis of reappraisal in PD patients, and all results showed abnormal activation in the prefrontal cortex 5,8. In these studies, the participants were required to transform negative stimuli into less distressing terms by generating their own alternative interpretation. Neuroimaging reviews in healthy individuals have reported that reappraisal recruits areas of the prefrontal cortex involved in effortful cognitive control 4,6. Increased effort and cognitive control may reflect the fact that individuals must generate their own alternative interpretation of images. Thus, it is unclear whether reappraisal-related abnormal brain activity in PD patients reflects emotion dysregulation or insufficient control of increased cognitive demands following reappraisal instructions. Given the interference of cognitive demands, it seems necessary to seek a more precise way to identify the underlying mechanism of cognitive reappraisal.
Therefore, in their recently published study, Zhang et al. 9 investigated the neural correlates and time course of cognitive reappraisal in PD patients using a passive cognitive reappraisal paradigm by event-related potentials. In this task, participants received a brief description of an image before viewing it. Prior to a negative image, the description was either neutral or negative. In the control group, the authors found that the unpleasant pictures preceded by negative descriptions had increased late positive potential (LPP) amplitudes compared with the unpleasant pictures preceded by neutral descriptions. In contrast, in the PD group, larger LPP during the 1000–2000-ms window was observed when unpleasant pictures were preceded by neutral descriptions. This study suggests that cognitive reappraisal is impaired in PD patients. One important aspect of this paper is that this is the first study focusing on electrophysiological correlates of abnormal cognitive reappraisal in patients with PD. Furthermore, the current study used a passive cognitive reappraisal paradigm, avoiding the influence of increased task difficulty or some other cognitive process, to provide evidence that diminished LPP modulation supported abnormal cognitive reappraisal in patients with PD. The shift in description is responsible for subsequent changes in brain activity, rather than increased cognitive demands following reappraisal instructions.
This research indeed provides us with important new data on impaired cognitive reappraisal in PD; however, the deeper significance of the research task and results goes beyond this. In this task, participants received a brief description of the forthcoming image and then simply viewed the picture. In this way, participants were provided with a description that could influence the meaning of the forthcoming image unconsciously, rather than being left to generate their own reinterpretation. During passive viewing of negative images, individuals are not instructed to regulate their feelings, but only to wait and see. Accordingly, the cognitive regulatory process is triggered and occurs outside of awareness.