Distinct conflict resolution deficits related to different facets of Schizophrenia

Influence of empathetic pain processing on cognition in schizophrenia

Deficits in both empathy and cognition have been reported widely in patients with schizophrenia. However, little is known about how these deficits interact among such patients. In the present study, we used pain portraying pictures preceding a color-word Stroop task to investigate the effect of empathetic pain observation on cognition among patients with schizophrenia. Twenty patients with schizophrenia and twenty healthy controls were included. The control group showed increased Stroop facilitation and decreased interference during the empathetic pain condition compared with the non-empathetic condition. Although patients with schizophrenia exhibited deficits in cognition, they demonstrated a similar empathy effect to controls on Stroop facilitation, but a somewhat larger empathy effect on Stroop interference (a more decreased effect). In particular, the groups did not differ in either automatic or controlled processing during the non-empathetic condition, suggesting general rather than specific cognitive deficits in schizophrenia. Together, we interpret our findings in terms of two opposing effects of empathy on cognition in schizophrenia, with possible neuromodulatory mechanism. Whereas prior studies showed empathy to be impaired, our outcomes indicate that at least some components of empathetic pain processing are preserved in such patients.

Inhibiting reactions to emotional versus non-emotional response cues in schizophrenia: Insights from a motor-process paradigm

Recent models of schizophrenia suggest deficient use of contextual response cues when confronted with countermanding emotional cues. It is important to clinically validate these models by testing patients diagnosed with schizophrenia on tasks with competing emotional and contextual response determinants. Control and schizophrenia groups completed a novel task that elicited motor responses consistent with, or in opposition to, pre-potent emotional actions (i.e., approach vs. avoidance). An analogous non-emotional task was also used to examine cue-conflict impairment more generally. The groups demonstrated statistically equivalent performance decrements on incongruent versus congruent trials on both tasks. However, within the schizophrenia group, the incongruency effect was significantly greater in the emotional versus non-emotional task. These data suggest that, while patients with schizophrenia were able to employ contextual response cues to override competing emotional responses, they were slower to resolve emotional versus non-emotional response conflict. When patients were subdivided according to the presence or absence of disorganized symptoms, this effect was confined to patients with disorganized symptoms.

Perception of emotion-related conflict in human communications: what are the effects of schizophrenia?

Our ability to make sense of emotional cues is of paramount importance for understanding state of mind and communicative intent. However, emotional cues often conflict with each other; this presents a significant challenge for people with schizophrenia. We conducted a theoretical review to determine the extent and types of impaired processing of emotion-related conflict in schizophrenia; we evaluated the relationship with medication and symptoms, and considered possible mediatory mechanisms. The literature established that people with schizophrenia demonstrated impaired function: (i) when passively exposed to emotion cues whilst performing an unrelated task, (ii) when selectively attending to one source of emotion cues whilst trying to ignore interference from another source, and (iii) when trying to resolve conflicting emotion cues and judge meta-communicative intent. These deficits showed associations with both negative and positive symptoms. There was limited evidence for antipsychotic medications attenuating impaired emotion perception when there are conflicting cues, with further direct research needed. Impaired attentional control and context processing may underlie some of the observed impairments. Neuroanatomical correlates are likely to involve interhemispheric transfer via the corpus callosum, limbic regions such as the amygdala, and possibly dorsolateral prefrontal and anterior cingulate cortex through their role in conflict processing.

EEG activity represents the correctness of perceptual decisions trial-by-trial

Performance monitoring is an executive function, which we depend on for detecting and evaluating the consequences of our behavior. Although event related potentials (ERPs) have revealed the existence of differences after correct and incorrect decisions, it is not known whether there is a trial-by-trial representation of the accuracy of the decision. We recorded the electroencephalographic activity (EEG) while participants performed a perceptual discrimination task, with two levels of difficulty, in which they received immediate feedback. Receiver Operating Characteristic (ROC) analyses were used to reveal two components that convey trial-by-trial representations of the correctness of the decisions. Firstly, the performance monitoring-related negativity (PM-N), a negative deflection whose amplitude is higher (more negative) after incorrect trials. Secondly, the performance monitoring-related positivity (PM-P), a positive deflection whose amplitude is higher after incorrect trials. During the time periods corresponding to these components, trials can be accurately categorized as correct or incorrect by looking at the EEG activity; this categorization is more accurate when based on the PM-P. We further show that the difficulty of the discrimination task has a different effect on each component: after easy trials the latency of the PM-N is shorter and the amplitude of the PM-P is higher than after difficult trials. Consistent with previous interpretations of performance-related ERPs, these results suggest a functional differentiation between these components. The PM-N could be related to an automatic error detection system, responsible for fast behavioral corrections of ongoing actions, while the PM-P could reflect the difference between expected and actual outcomes and be related to long-term changes in the decision process.

ERP Evidence of a Stroop-Like Effect in Emotional Speech Related to Social Anhedonia

The present study investigated the ERP correlates of the integration of emotional prosody to the emotional meaning of a spoken word. Thirty-four nonclinical participants listened to negative and positive words that were spoken with an angry or happy prosody and classified the emotional valence of the word meaning while ignoring emotional prosody. Social anhedonia was also self-rated by the subjects. Compared to congruent trials, incongruent ones elicited slower and less accurate behavioral responses, and a smaller P300 component at the brain response level. The present data suggest that vocal emotional information is salient enough to be integrated early in verbal processing. The P300 amplitude modulation by the prosody-meaning congruency positively correlated with the social anhedonia score, suggesting that the sensitivity of the electrical brain response to emotional prosody increased with social anhedonia. Interpretations of this result in terms of emotional processing in social anhedonia are discussed.

Conflict and error processing in an extended cingulo-opercular and cerebellar network in schizophrenia

The loss of cognitive control is a prominent feature of schizophrenia. Relevant for adaptive control, individuals with schizophrenia often show impairments in their ability to monitor their ongoing behavior, and to adjust their responses based on advance information or feedback. By conducting a systematic examination of the behavioral adjustments after error and conflict and of activity within and between brain regions sensitive to the need to increase control (i.e. error commission, conflict presentation) in individuals with schizophrenia (n = 38) compared to healthy controls, we aimed to 1) shed light on the role of diverse brain regions previously associated with adaptive cognitive control, and 2) contribute to our understanding of the nature of the cognitive deficits present in individuals with schizophrenia. Our results show that error- and conflict-related behavioral adjustments are relatively intact during the performance of a change-signal task. Similarly, individuals with schizophrenia demonstrated intact error- and conflict-related effects in the dorsal anterior cingulate cortex, as well as in a number of other key regions including the bilateral anterior prefrontal cortex (PFC), bilateral insula, right inferior parietal lobule during error processing, and bilateral inferior parietal lobule and thalamus, right anterior PFC, left insula, and left lateral and inferior cerebellum during conflict processing. Given that a critical characteristic of our experimental design was the use of tasks that explicitly provide information about errors and conflict, we interpret our results as suggesting that the error- and conflict-detection systems are still somewhat functional in individuals with schizophrenia, but that a compromise in the ability to represent task relevant information that allow for the generation of an error representation may lead to the alterations in error- and conflict-processing documented in the schizophrenia literature.

Impaired error-likelihood prediction in medial prefrontal cortex in schizophrenia

The cognitive impairment in individuals with schizophrenia includes deficits of working memory in dorsolateral prefrontal cortex and deficits of performance monitoring in medial prefrontal cortex (MPFC). Recent work suggests a more general role for MPFC in predicting the outcome of actions and then evaluating those predictions. Here we investigate, in individuals with schizophrenia, two specific effects associated with this role: the error likelihood effect (occurring on trials with correct performance, but features that predict a high probability of errors), and the error unexpectedness effect (occurring on trials with an error, but features that predict errors are of low probability). In a rapid event-related fMRI design with a modified version of the change-signal task, a cue incidentally predicting error likelihood was encoded into working memory by participants in order to perform a secondary delayed match-to-sample task. There were four key findings: (1) individuals with schizophrenia exhibited poorer working memory performance and reduced error signals in MPFC; (2) even in control and schizophrenia subgroups matched on working memory performance, the schizophrenia subgroup showed a deficit in error-likelihood prediction in MPFC at the time of the predictive cue; (3) the schizophrenia subgroup also showed a deficit in evaluative error-unexpectedness activity when errors were committed; and (4) a mediation analysis indicated that error-likelihood predictions successfully explained error-unexpectedness evaluations in both controls and patients. Collectively, these findings suggest that individuals with schizophrenia have a disturbance in the evaluation of outcomes that is the result of a primary deficit in the prediction of error likelihood in MPFC.