In comparison to controls, patients with psychosis presented problems in both ToM and emotion recognition (ER). Nevertheless, solely problems in ER were related to delusional distress, but not related to other measures of delusions. Problems in ER also had an impact on the quality of the therapeutic alliance and interactional problems viewed by the therapist. Finally, good ER ability reduced the negative impact of delusional frequency on both the quality of the therapeutic relationship and interactional problems during CBT/ST.
The present study is the first study reporting that problems in ER are associated with delusional distress, whereas there were no further associations with other measures of delusions. In particular, problems in recognizing the negative emotions fear and disgust were related with more pronounced delusional distress, whereas problems in recognizing the emotions anger and sadness were not related to delusional distress. Our results suggest that problems in ER (especially problems in recognizing fear and disgust) might not be directly related to the presence of delusions, but enhance the distress associated with them, in line with experimental designs suggesting that problems in ER are more pronounced in stressful situations in patients with psychosis (49). It is possible that in stressful situations, patients with psychosis are less able to interpret social cues correctly and perform more errors in recognizing emotions and in inferring emotional states of other persons (50, 51) and this might lead to interactional problems and reduced social functioning (23). Thus, it might be useful to further investigate using longitudinal assessments whether problems in ER - although not directly associated with the intensity of delusions - might increase delusional distress. In addressing this question, it is highly important to measure ER problems with regard to specific negative emotions, as our results demonstrate that problems in recognizing the emotions fear and disgust are related to delusional distress, whereas problems in recognizing anger and sadness were not related to more pronounced delusional distress. If longitudinal associations between problems in ER and specific negative emotions and delusional distress are further established, ER problems should then be included as one of the cognitive factors involved in the development and maintenance of delusional distress in theoretical models.
The fact that we did not find an association between ToM problems and any measure of delusions nor delusional frequency / distress is in line with findings of two meta-analyses (14, 18) and several other studies that did not report an association between ToM and delusions (8, 52, 53), whereas negative symptoms and symptoms of disorganisation are more constantly associated with ToM problems (14). One explanation might be that ToM problems are less pronounced in patients with delusions in comparison to patients with negative or disorganized symptoms (e.g. (54, 55), see Spronghorst et al. for a review on the literature of subgroup comparisons (56)) and thus, harder to assess using typical ToM paradigms that sometimes lack ecological validity (57). Interestingly, all studies that used more ecologically valid ToM assessments such as movies of social situations (e.g. the Movie of Assessment of Social Cognition (MASC) (58) or the Movie Task of social situations (20)), found associations between ToM problems and more pronounced general and persecutory delusions in patients with psychosis (59).
An additional limitation of current ToM paradigms is the fact that they often measure ToM in a wright-or-wrong format and thus investigate solely reduced ToM abilities/undermentalizing in patients with psychosis, whereas Frith (60) suggested that patients with delusion rather present problems in overmentalizing mental states of other persons, defined as Hyper-ToM (58, 61). First studies addressed the question of associations between Hyper-ToM and delusions in children with psychotic experiences and normal controls (62, 63) and patients with psychosis (58) and found evidence of an association. Thus, Hyper-ToM rather than undermentalizing might play an important role in the formation and maintenance of delusions and should be investigated in future studies.
Concluding, future studies that address the question of associations between ToM problems and delusions might be well-advised to use tasks with more pronounced ecological validity, for example, ToM assessment using videos, virtual reality (Virtual Assessment of Mentalising Ability (VAMA) (64) or investigating ToM problems in real-life using the experience sampling methods (65). Nevertheless, if there are still no associations between problems in Hyper-ToM and delusions, theoretical models correctly excluded ToM as one of the important cognitive factors involved in the formation and maintenance of delusions or positive symptoms (12, 13).
Our study is the first to report that therapists who treated patients with problems in ER (especially problems in recognizing the emotions disgust and fear) perceived more pronounced interactional problems in these patients. In addition, therapists who treated patients with problems in ER (especially in recognizing the emotions fear, anger, sadness and disgust) rated the quality of the therapeutic relationship more negatively. Our findings are partly in line with the study of Jung and colleagues (29) who reported an association between patients’ ratings on the quality of the therapeutic alliance and ToM problems, but no associations between therapists’ ratings and ToM problems, but the size of our study sample enabled us to detect associations of medium and small effect size. Nevertheless, it has to be taken into account, that our results were not pre-specified, but obtained in an exploratory analysis of a randomized-controlled therapy trial, thus, careful replication of our results should be performed, especially in light of the current replication crisis in psychology (see (66) for a review)). If our results are successfully replicated and patients’ problems in ER influence the relationship with an empathetic and highly skilled therapist, it can be assumed that their problems in ER also have a negative impact on other social interactions in their daily life, as suggested by several other studies that directly addressed this question (21, 22).
In addition, we could provide evidence for the clinically important negative impact of delusional frequency on both the therapeutic relationship and interactional problems viewed by the therapist. Again, it is important to note these results were obtained in an exploratory analysis and thus are in need of careful replication. If our findings are replicated in longitudinal assessments, they suggest that delusional frequency negatively affects social interactions (the therapeutic interactions) and thus may also partly contribute to the association between delusions and lower social functioning (67, 68), negative family atmosphere (69), more pronounced loneliness (70, 71) and social exclusion (72, 73).
Further, preserved ER abilities might protect patients from the negative influence of their delusions on the quality of the therapeutic relationship and interactional problems, as a statistically significant moderation effect occurred. Interestingly, the interaction was most pronounced in patients with severe ER problems: in this subgroup, problems in ER had a specific negative influence on both the therapeutic relationship and interactional problems. Our results are partly supported by a second study that addressed the impact of ToM on the association between delusions and self-rated social functioning (31). Their results also suggest that preserved ToM abilities moderated the relationship between persecutory delusions and self-rated social functioning (31). The fact that we did not find a similar moderation effect between ToM and the quality of the therapeutic relationship could be explained by different ToM assessments (the study used the Hinting task (54)) that is based on verbal descriptions of social situations, we used a picture sequencing test based on comics. To some degree, our findings expand on their results, as we used therapists’ ratings of the therapeutic alliance as a direct measure of social functioning instead of self-ratings. Again, if our exploratory findings can be replicated and positive ER skills are a protecting factor against the negative influence of delusions on the therapeutic relationship, patients’ ER abilities might also influence the effectiveness of CBT for psychosis, as a positive therapeutic relationship is closely related to the effectiveness of CBT (28, 74, 75). Interestingly, one study indeed found general ToM abilities (including ER) to moderate change in positive symptoms in CBT (76). Thus, interventions that improve ER and ToM abilities might be beneficial in order to improve the therapeutic relationship and, further, the effectiveness of CBT.
ER and ToM problems in patients with psychosis can also be viewed in a broader perspective as parts of patients’ more general problems in their metacognitive capacities. Metacognition has been defined as “cognition about cognition” by Flavell (77) and also discussed as an important part of social cognition (78). Both ToM and ER are important parts of metacognition, in combination with self-reflectivity (comprehension of one’s own mental state), decentration (the ability to from a complex representation of the world) and mastery, the ability to use information of one’s own and other mental states in respond to and to solve social and psychological problems (79).
In comparison to controls, patients with psychosis were found to present problems in almost all parts of metacognition (see Lysaker et al. (79) for a review on metacognition in schizophrenia). Metacognitive abilities in patients with psychosis are closely linked to a positive therapeutic relationship viewed by patients in CBT (mastery (80)) and also with positive outcome in Cognitive Remediation therapy (learning potential: (81)). Thus, as ER is an important part of metacognition, it is plausible that we also found a link between problems in ER and a less favourable therapeutic relationship and interactional problems viewed by the therapist, as ER can be viewed as one part of metacognitive mastery that was also found to be linked to a positive therapeutic relationship (80). Thus, the association between problems in ER and a less favourable therapeutic relationship could be moderated by general metacognitive deficits in patients with psychosis. Therapists might perceive these deficits during the first therapeutic sessions and these problems might influence the therapeutic relationship.
For example, patients with deficits in ER and metacognition might present problems in their metacognitive self-reflection that could become visible in diagnostic sessions, as they might not be able to talk about their individual thoughts and emotions in specific situations. They also might present problems in understanding the basic cognitive model that consists of relations between individual perceptions, thoughts, emotions and behaviour (82) due to their problems in self-reflection. Further, patients might also present problems in decentration and thus might not be able to form a complex representation of the world that is important in therapy in order to solve personal and interpersonal problems, e.g. due to their well-known jumping-to-conclusions-bias (83). Finally, patients’ level of mastery in using their information on mental states in order to solve real-world problems might also be reduced.
Concluding, it is possible that the association between poor emotion recognition and the therapeutic relationship/interactional problems viewed by the therapist can be explained by patients’ metacognitive problems. In addition, it is plausible that not only ER abilities but also a positive metacognitive performance might moderate the influence of delusional frequency on the therapeutic relationship and thus, might also be helpful for patients with psychosis in their general social life, as suggested by a study that found metacognitive capacities to mediate the negative influence of neurocognitive deficits on social functioning in patients with psychosis (84). Thus, future studies will be well-advised to address all aspects of metacognition in patients with psychosis and their influence on the therapeutic relationship.
Our results suggest for therapists of patients with psychosis to take patients’ potential ER problems (and their metacognitive deficits) into account in CBT for psychosis. First, it could be useful to assess patients with regard to their ER abilities before start of therapy. Second, if patients present ER problems, it is important for therapists to make a special effort to improve the therapeutic relationship with these patients. Third, it could be helpful to train ER (and metacognition) in patients with psychosis using specialized interventions from several social cognition trainings in the framework of Cognitive Remediation (85): the Social Cognition and Interaction Training (86) and the Metacognitive Training (Moritz and Woodward (87)) aim on improving both ToM and ER, whereas the Training of Affect Recognition (41) aims more closely on ER. In general, these trainings were able to enhance both ToM and ER abilities (86, 88-90) and their general effect on social functioning is large (91, 92). It is also possible, that an integration in or a combination of these trainings with CBT in order to improve ER might be beneficial.
Strength and limitations
Strengths of the present study include the large sample of patients with psychosis and the detailed assessment of different dimensions of delusions. An additional strength is the longitudinal assessment of the quality of the therapeutic relationship over five sessions.
In interpreting our findings, it should be mentioned that all associations between ToM, ER, delusions and the therapeutic relationship were of small effect size according to Cohen (93). In addition, it should be noted that solely two of the four scientific hypotheses were pre-specified, whereas all associations between ER, ToM, delusions and the therapeutic relationship were of exploratory nature. Thus, the question of associations between ToM, ER and the therapeutic relationship and the moderation effect require an additional careful replication study.
In addition, while our moderation model and the mode of assessment (ER and delusions were assessed before the start of therapy) suggest a causal association between problems in ER and delusional frequency and also implicate that positive ER abilities moderate the association between delusional frequency and the therapeutic relationship, we cannot rule out the possibility that a low quality of the therapeutic relationship and interactional problems were influenced by other factors, e.g. common therapeutic factors such as therapists’ empathy, expertness, attractiveness and trustworthiness (94, 95) and thus, it is also possible that an unfavourable therapeutic relationship might lead to more pronounced delusions in patients with psychosis. Thus, future studies should focus on symptom change, ER and the therapeutic relationship using multiple assessments in order to address the question whether more pronounced ER problems cause more pronounced delusional frequency/distress and a less favourable therapeutic relationship (or vice versa).
Finally, it should be mentioned that the patients in the present study were patients interested in participating in a therapy trial who might present better general cognitive and social functioning and less pronounced problems in their social cognition. Nevertheless, as the moderation effect occurred predominantly in patients with lower ER skills, a potential selection bias might not influence the generalisation of our exploratory results.