Impaired implicit emotion regulation in patients with panic disorder: An event-related potential study on affect labeling.

BACKGROUND: Panic disorder (PD) involves emotion dysregulation, but its underlying mechanisms remain poorly understood. Previous research suggests that implicit emotion regulation may play a central role in PD-related emotion dysregulation and symptom maintenance. However, there is a lack of studies exploring the neural mechanisms of implicit emotion regulation in PD using neurophysiological indicators. AIM: To study the neural mechanisms of implicit emotion regulation in PD with event-related potentials (ERP). METHODS: A total of 25 PD patients and 20 healthy controls (HC) underwent clinical eva-luations. The study utilized a case-control design with random sampling, selecting participants for the case group from March to December 2018. Participants performed an affect labeling task, using affect labeling as the experimental condition and gender labeling as the control condition. ERP and behavioral data were recorded to compare the late positive potential (LPP) within and between the groups. RESULTS: Both PD and HC groups showed longer reaction times and decreased accuracy under the affect labeling. In the HC group, late LPP amplitudes exhibited a dynamic pattern of initial increase followed by decrease. Importantly, a significant group × condition interaction effect was observed. Simple effect analysis revealed a reduction in the differences of late LPP amplitudes between the affect labeling and gender labeling conditions in the PD group compared to the HC group. Furthermore, among PD patients under the affect labeling, the late LPP was negatively correlated with disease severity, symptom frequency, and intensity. CONCLUSION: PD patients demonstrate abnormalities in implicit emotion regulation, hampering their ability to mobilize cognitive resources for downregulating negative emotions. The late LPP amplitude in response to affect labeling may serve as a potentially valuable clinical indicator of PD severity.

[Abnormal automatic processing of facial expression in generalized anxiety disorder patients: an event-related potential study].

OBJECTIVE: To examine the automatic processing of facial expression and explore the pathogenesis in generalized anxiety disorder (GAD) patients. METHODS: Fifteen GAD patients and 15 gender-, age- and education-matched healthy volunteers were recruited from First Affiliated Hospital, Dalian Medical University. The expression-related mismatch negativity (MMN) was recorded to explore the automatic processing mechanism into emotional faces with task-irrelevant emotional faces as effective media. RESULTS: The MMNs elicited by emotional faces were significantly lower in GAD participants than those in healthy participants [MMN1:case group (-0.30 ± 0.09) µV, control group (-0.68 ± 0.13) µV, P = 0.0003; MMN2: case group (-0.22 ± 0.13) µV, control group (-0.72 ± 0.13) µV, P = 0.011] (Ps < 0.05) analyzing. For the effect of expression, it was found that the MMNs elicited by negative expression were lower in GAD participants than those in healthy participants mainly in right hemisphere while positive expression mainly in left hemisphere [MMN1:case group (-0.45 ± 0.15) µV, control group (-0.99 ± 0.15) µV, P = 0.017; MMN2:case group (0.23 ± 0.22) µV, control group (-1.23 ± 0.22) µV, P = 0.003; (MMN1:case group (-0.12 ± 0.14) µV, control group (-0.65 ± 0.14) µV, P = 0.015; MMN2:case group (0.14 ± 0.18) µV, control group (-0.42 ± 0.18) µV, P = 0.039]. CONCLUSION: There is an impairment of automatic processing of emotional faces.

Heightened sensitivity to panic-related sounds with reduced sensitivity to neutral sounds in preattentive processing among panic patients.

BACKGROUND: Hypervigilance to panic-related stimuli is believed to play a critical role in the pathogenesis of panic disorder. The current event-related potential study explored whether this hyperresponsivity occurred in the absence of focused attention. METHODS: Mismatch negativity (MMN) responses to panic-related vs. neutral deviants were assessed in 15 medication-free panic patients without agoraphobia and 16 healthy controls using a reverse-standard-deviant paradigm. RESULTS: Panic patients relative to healthy controls exhibited an enhanced MMN in response to panic-related sounds but a reduced MMN in response to neutral sounds. Furthermore, MMN responses were delayed in panic patients compared to healthy controls, irrespective of stimulus type. LIMITATION: The sample size is relatively small. CONCLUSIONS: Our data provide evidence that panic disorder was associated with an increased sensitivity to panic-related changes, accompanied by a reduced sensitivity to other acoustic changes as well as a general slow-down of cognitive processing during the preattentive processing stage.

Pre-attentive dysfunction of musical processing in major depressive disorder: A mismatch negativity study.

BACKGROUND: Deficits of pre-attentive information processing have been frequently found in patients with major depressive disorder, nevertheless the results are quite inconsistent due to clinical heterogeneity and methodological difference. Cognitive processing of music is a useful tool for investigating human cognition and its underlying brain mechanisms. Although general auditory processing and perception of musical sound are hampered in patients with MDD, whether the deficits in musical processing begin from pre-attentive stage is not well investigated yet. The present study aimed to investigate the MMN of musical sound in patients with MDD. METHOD: MMN responses to different musical features were compared in 20 patients with MDD and 20 age-matched healthy controls. The multi-feature paradigm was used to examine automatic change detection of six different musical sound features (pitch, timbre, location, intensity, slide, rhythm) in a complex musical context. Severity of depression and co-morbid anxiety were evaluated using the Hamilton Rating Scale of Depression (HRSD-17) and the Hamilton Anxiety Rating Scale (HAMA). RESULTS: MMNs were obtained with all deviants. The timbre-MMN was significantly larger in MDD patients than in healthy controls, while the other deviants (pitch, location, intensity, slide and rhythm) elicited similar MMN across groups. For MDD patients, the amplitudes and latencies of MMNs did not correlate with severity of depression or co-morbid anxiety. LIMITATIONS: The sample size in this study is relatively small. CONCLUSION: Patients with MDD do not perform at the same level as controls in automatic change detection of timbre. This dysfunction is considered to be a trait-dependent feature of MDD.

Mismatch negativity indices of enhanced preattentive automatic processing in panic disorder as measured by a multi-feature paradigm.

Panic disorder (PD) is a mental disorder characterized by recurrent panic attacks and worrying about having subsequent attacks. Mismatch negativity (MMN) has been established as a correlate of preattentive automatic processing. The aim of the present study is to investigate the preattentive automatic information processing in PD patients as measured by MMN. Subjects included 15 medication-free patients with a DSM-IV diagnosis of PD and 15 age-matched healthy volunteers. MMN was investigated using event-related potentials. The protocol used a multi-feature paradigm. Mean amplitudes and peak latencies were subjected to repeated-measures ANOVAs. PD patients showed a significantly increased MMN of sound intensity and location compared with healthy participants. The correlation between the amplitudes of intensity-MMN and disease severity was also significant. These data provide evidence of anomalous preattentive automatic information processing in PD patients. In particular, the abnormality may be specific for PD.

Mismatch negativity of sad syllables is absent in patients with major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is an important and highly prevalent mental disorder characterized by anhedonia and a lack of interest in everyday activities. Additionally, patients with MDD appear to have deficits in various cognitive abilities. Although a number of studies investigating the central auditory processing of low-level sound features in patients with MDD have demonstrated that this population exhibits impairments in automatic processing, the influence of emotional voice processing has yet to be addressed. To explore the automatic processing of emotional prosodies in patients with MDD, we analyzed the ability to detect automatic changes using event-related potentials (ERPs). METHOD: This study included 18 patients with MDD and 22 age- and sex-matched healthy controls. Subjects were instructed to watch a silent movie but to ignore the afferent acoustic emotional prosodies presented to both ears while continuous electroencephalographic activity was synchronously recorded. Prosodies included meaningless syllables, such as "dada" spoken with happy, angry, sad, or neutral tones. The mean amplitudes of the ERPs elicited by emotional stimuli and the peak latency of the emotional differential waveforms were analyzed. RESULTS: The sad MMN was absent in patients with MDD, whereas the happy and angry MMN components were similar across groups. The abnormal sad emotional MMN component was not significantly correlated with the HRSD-17 and HAMA scores, respectively. CONCLUSION: The data indicate that patients with MDD are impaired in their ability to automatically process sad prosody, whereas their ability to process happy and angry prosodies remains normal. The dysfunctional sad emotion-related MMN in patients with MDD were not correlated with depression symptoms. The blunted MMN of sad prosodies could be considered a trait of MDD.

Visual mismatch negativity in the detection of facial emotions in patients with panic disorder.

Panic disorder is a highly prevalent mental disease characterized by sudden and recurrent panic attacks. Studies on patients with panic disorder have found dysfunctional strategic processing of facial expressions and abnormal automatic processing of panic-related stimuli. However, whether the automatic processing of facial emotions in patients with panic disorder is normal is unknown. Visual mismatch negativity (vMMN) reflects automatic processing of change detection. We recorded expression-related vMMN to compare the automatic detection of schematic facial emotions (negative and positive) of 12 patients with panic disorder and 17 age-matched and education-matched controls. During the late time window (220-330 ms), the vMMN amplitudes for two emotions (negative and positive) were significantly decreased in patients with panic disorder (P=0.02). This finding implies that the ability to automatically detect facial emotions is impaired in patients with panic disorder. This is the first report on expression-related vMMN being used with patients with panic disorder.

Dysfunction of preattentive visual information processing among patients with major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is a mental disorder characterized by depressed mood and inability to experience pleasure. Mismatch negativity (MMN) has been established as a correlate of preattentive change detection. In this study, preattentive processing of visual information in MDD patients was investigated using visual MMN (vMMN), and an abnormal vMMN was predicted in depressed patients relative to healthy participants because of dysfunction at the preattentive level. The processes underlying vMMN in MDD patients were also explored, and memory-based comparison preattentive processing was hypothesized to be impaired in MDD patients. METHODS: Subjects included 14 medication-free patients (41.4 ± 12.6 years) with a DSM-IV diagnosis of MDD and 14 age-matched healthy volunteers (41.7 ± 17.5 years). vMMN was investigated using event-related potentials. The protocol used both an equiprobable sequence and a traditional oddball sequence, and three kinds of difference waves (i.e., deviant-minus-standard, deviant-minus-control, and control-minus-standard) were investigated. Mean amplitudes and peak latencies were subjected to repeated-measures analysis of variance. RESULTS: Although MDD patients showed no reduction in the oddball-vMMN (deviant-minus-standard), they showed a significantly decreased deviant-minus-control difference waves and a trend for an increased control-minus-standard difference waves compared with healthy participants. CONCLUSIONS: These data provide evidence for anomalous preattentive information processing in MDD patients. In particular, the abnormality may be due to an attenuated memory-based comparison process and an enhanced refractory process.