Ahmad Abu-Akel

Neuroanatomical and neurochemical bases of theory of mind

This paper presents a novel neurobiological model of theory of mind (ToM) that incorporates both neuroanatomical and neurochemical levels of specificity. Within this model, cortical and subcortical regions are functionally organized into networks that subserve the ability to represent cognitive and affective mental states to both self and other. The model maintains that (1) cognitive and affective aspects of ToM are subserved by dissociable, yet interacting, prefrontal networks. The cognitive ToM network primarily engages the dorsomedial prefrontal cortex, the dorsal anterior cingulate cortex and the dorsal striatum; and the affective ToM network primarily engages the ventromedial and orbitofrontal cortices, the ventral anterior cingulate cortex, the amygdala and the ventral striatum; (2) self and other mental-state representation is processed by distinct brain regions within the mentalizing network, and that the ability to distinguish between self and other mental states is modulated by a functionally interactive dorsal and ventral attention/selection systems at the temporoparietal junction and the anterior cingulate cortex; and (3) ToM functioning is dependent on the integrity of the dopaminergic and serotonergic systems which are primarily engaged in the maintenance and application processes of represented mental states. In addition to discussing the mechanisms involved in mentalizing in terms of its component processes, we discuss the models implications to pathologies that variably impact ones ability to represent, attribute and apply mental states.

The Social Salience Hypothesis of Oxytocin

Oxytocin is a nonapeptide that also serves as a neuromodulator in the human central nervous system. Over the last decade, a sizeable body of literature has examined its effects on social behavior in humans. These studies show that oxytocin modulates various aspects of social behaviors such as empathy, trust, in-group preference, and memory of socially relevant cues. Several theoretical formulations have attempted to explain the effects of oxytocin. The prosocial account argues that oxytocin mainly enhances affiliative prosocial behaviors; the fear/stress theory suggests that oxytocin affects social performance by attenuating stress; and the in-/out-group approach proposes that oxytocin regulates cooperation and conflict among humans in the context of intergroup relations. Nonetheless, accumulating evidence reveals that the effects of oxytocin are dependent on a variety of contextual aspects and the individuals characteristics and can induce antisocial effects including aggression and envy. In an attempt to reconcile these accounts, we suggest a theoretical framework that focuses on the overarching role of oxytocin in regulating the salience of social cues through its interaction with the dopaminergic system. Crucially, the salience effect modulates attention orienting responses to external contextual social cues (e.g., competitive vs. cooperative environment) but is dependent on baseline individual differences such as gender, personality traits, and degree of psychopathology. This view could have important implications for the therapeutic applications of oxytocin in conditions characterized with aberrant social behavior.

Risk factors for violence among patients with schizophrenia.

Studies of birth cohorts show evidence of greater risk of violence among patients with schizophrenia compared to the general population. However, the contribution of schizophrenia to violence is heavily debated and remains unclear. This debate has spurred research whose focus can be associated with one of the following areas: psychotic symptoms, personality disorders (in particular psychopathy), mentalizing abilities, substance abuse and demographic factors. The aim of the current review is to evaluate the predictive role of these risk factors in the occurrence of violence among patients with schizophrenia. We identified two different trajectories for violent behavior in schizophrenia: one pertains to patients with no prior history of violence or criminal behavior and for whom positive symptoms appear to explain violent behavior, and another where personality pathology, including psychopathy, predict violence, regardless of other symptomatology associated with schizophrenia. Furthermore, emergent data suggest that specific mentalizing profiles can be associated with the occurrence of violence in schizophrenia, an issue that warrants further consideration in future research.

The association between autism and schizophrenia spectrum disorders: A review of eight alternate models of co-occurrence

Although now believed to be two distinct disorders, autism spectrum disorders (ASD) and schizophrenia spectrum disorders (SSD) share multiple phenotypic similarities and risk factors, and have been reported to co-occur at elevated rates. In this narrative review, we give a brief overview of the phenomenological, genetic, environmental, and imaging evidence for the overlap between ASD and SSD, highlighting similarities and areas of distinction. We examine eight possible alternate models of explanation for the association and comorbidity between the disorders, and set out a research agenda to test these models. Understanding how and why these disorders co-occur has important implications for diagnosis, treatment, and prognosis, as well as for developing fundamental aetiological models of the disorders.

‘Theory of mind’ in violent and nonviolent patients with paranoid schizophrenia

The role of mentalizing abilities (or theory of mind) and empathic abilities in violent behavior were studied in 24 hospitalized males with paranoid schizophrenia (ICD-10). Patients were divided into violent and nonviolent groups based on their history of committing violent acts against others. To examine these abilities, patients heard a series of 12 short scenarios depicting social situations followed by questions that require making mental state or empathic inferencing. Our results show that violent patients have more difficulties than nonviolent patients in tasks involving empathic inferencing, and better abilities in inferring cognitive-mental states in others. In addition, violence seems to be associated with a history of alcohol and drug abuse, young age, and the hostility component of the Brief Psychiatric Rating Scale. Logistic regression analyses suggest that violence is associated with the combination of hostility towards others, good mentalizing abilities and poor empathy. These results are discussed in light of recent theories on violent behavior in psychiatric populations.

Oxytocin increases empathy to pain when adopting the other- but not the self-perspective

There is growing evidence that the neuropeptide oxytocin (OT) facilitates various forms of sensitivity to others, but the mechanism by which OT enhances empathy in humans is unclear. In this study, we examined whether OT increases empathy by the way of blurring the distinction between self and other, or by enhancing the difference between self and other. In this double-blind, placebo-controlled, within-subject crossover design, empathic responses of healthy participants were compared when imagining oneself (i.e., self-perspective empathy) versus when imagining the other (i.e., other-perspective empathy) in painful and nonpainful situations. Under OT treatment, participants expressed more empathy when imagining others than when imagining oneself in pain. This was in contrast to the placebo condition where there were no differences between the empathic responses during the self- and the other-perspective. We propose that the modulatory effect of OT on empathy when taking the other-perspective may be mediated by its role in self- and other-distinctiveness and corollary by its role in increasing salience to social agents and cues.

Association of psychopathic traits and symptomatology with violence in patients with schizophrenia

The main aim of the current study is to investigate the association of psychopathic traits and symptomatology with violence in male patients with schizophrenia. The Psychopathy Checklist-Revised (PCL-R) and the Brief Psychiatric Rating Scale (BPRS) were administered to 35 hospitalized male patients diagnosed with schizophrenia. Based on their history of violence, the sample was divided into violent (N = 19) and nonviolent (N = 16) groups. Data were analyzed using parametric, nonparametric and regression analyses. The mean psychopathy and hostility (component of the BPRS) scores were significantly higher for the violent group. Only three patients (16%), all from the violent group, met the diagnostic cutoff for psychopathy (a PCL-R score > or = 30). Regression analyses suggest that both the hostility component of the BPRS and the behavioral component of the PCL-R (Factor 2) are significant predictors of violent behavior in male patients with schizophrenia. However, when the psychopathy scores are high, the probability for violence is already considerable and the level of hostility has only a slight effect. These findings suggest that improvement in illness condition may not reduce the likelihood for violence in male patients with a high psychopathic profile.

Perspective-taking abilities in the balance between autism tendencies and psychosis proneness

Difficulties with the ability to appreciate the perspective of others (mentalizing) is central to both autism and schizophrenia spectrum disorders. While the disorders are diagnostically independent, they can co-occur in the same individual. The effect of such co-morbidity is hypothesized to worsen mentalizing abilities. The recent influential ‘diametric brain theory’, however, suggests that the disorders are etiologically and phenotypically diametrical, predicting opposing effects on ones mentalizing abilities. To test these contrasting hypotheses, we evaluated the effect of psychosis and autism tendencies on the perspective-taking (PT) abilities of 201 neurotypical adults, on the assumption that autism tendencies and psychosis proneness are heritable dimensions of normal variation. We show that while both autism tendencies and psychosis proneness induce PT errors, their interaction reduced these errors. Our study is, to our knowledge, the first to observe that co-occurring autistic and psychotic traits can exert opposing influences on performance, producing a normalizing effect possibly by way of their diametrical effects on socio-cognitive abilities. This advances the notion that some individuals may, to some extent, be buffered against developing either illness or present fewer symptoms owing to a balanced expression of autistic and psychosis liability.

Superior mentalizing abilities of female patients with schizophrenia

Mentalizing abilities are severely disrupted in patients with schizophrenia, but gender-related differences in this domain are virtually unexplored. Given the importance of these abilities in understanding psychopathology, social functioning and outcome, this study aimed to examine the mentalizing abilities of male and female patients with schizophrenia. The cognitive and affective mentalizing abilities of self and other of clinically stable male and female patients with schizophrenia were analyzed using the abbreviated version of the Metacognitive Assessment Scale (MAS-A). Compared to their male counterparts, the female patients demonstrated superior overall mentalizing abilities. This advantage was also evident when mentalizing about the Self or the Other. When examining cognitive versus affective mentalizing, women were significantly better in their ability to attribute and understand the affective mental states of others. These differences were unrelated to intelligence or psychopathology. The superior mentalizing abilities of female patients extend gender-related differences in schizophrenia to include social cognition. This suggests that our current knowledge of socio-cognitive abilities in schizophrenia is generalizable to male but not to female patients. The findings also provide important insights to understanding how etiological differences affect social cognition. Awareness to such differences has important implications for diagnosis and clinical treatment.

Mentalizing mediates the relationship between psychopathy and type of aggression in schizophrenia.

Abstract Convincing evidence demonstrates that psychopathy is associated with premeditated aggression. However, studies have failed to explain why this association exists and whether socio-cognitive functions, such as mentalizing, could explain the relation. This cross-sectional study investigates, in 108 patients with schizophrenia, the association of psychopathy and mentalizing abilities with premeditated and impulsive aggression and probes the nature of their influence on these specific aggression patterns. Patients’ engagement in premeditated aggression was associated with diminishing mentalizing and increasing psychopathic tendencies. Moreover, mediation analyses reveal that the ability to attribute mental states to others mediates the relation between psychopathy and type of aggression. This mediation is facilitated by a specific mentalizing profile characterized by the presence of intact cognitive and deficient emotional mentalizing capacities. This study is the first to report a mediating effect of mentalizing on the relationship between psychopathy and type of aggression in schizophrenia. Implications of these results are discussed.