Riccardo Maria Martoni

Executive functioning in anorexia nervosa patients and their unaffected relatives

Formal genetic studies suggested a substantial genetic influence for anorexia nervosa (AN), but currently results are inconsistent. The use of the neurocognitive endophenotype approach may facilitate our understanding of the AN pathophysiology. We investigated decision-making, set-shifting and planning in AN patients (n=29) and their unaffected relatives (n=29) compared to healthy probands (n=29) and their relatives (n=29). The Iowa Gambling Task (IGT), the Tower of Hanoi (ToH) and the Wisconsin Card Sorting Test (WCST) were administered. Concordance rates and heritability indices were also calculated in probands/relatives. Impaired performance on the IGT and the WCST were found in both AN probands and their relatives, although planning appeared to be preserved. The IGT heritability index suggested the presence of genetic effects that influence this measure. No evidence for genetic effects was found for the WCST. The results suggest the presence of a shared dysfunctional executive profile in women with AN and their unaffected relatives, characterized by deficient decision-making and set-shifting. Concordance analysis strongly suggests that these impairments aggregate in AN families, supporting the hypothesis that they may constitute biological markers for AN. Decision-making impairment presents a moderate heritability, suggesting that decision-making may be a candidate endophenotype for AN.

Motor inhibition and cognitive flexibility in eating disorder subtypes

Anorexia Nervosa (AN) and Bulimia Nervosa (BN) are complex Eating Disorders (EDs). Even if are considered two different diagnostic categories, they share clinical relevant characteristics. The evaluation of neurocognitive functions, using standardized neuropsychological assessment, could be a interesting approach to better understand differences and similarities between diagnostic categories and clinical subtypes in EDs thus improving our knowledge of the pathophisiology of EDs spectrum. This study explored cognitive flexibility and motor inhibition in patients with AN considering both Restricter and Binge/Purge subtypes, patients with BN and healthy comparisons subjects (HC). Intra-Extra Dimentional Set shifting Test and Stop Signal Task, selected from CANTAB battery, were administered to analyzed set-shifting and motor inhibition respectively. AN patients showed a deficient motor inhibition compared to HC, while no evidence for impaired motor inhibition was found in BN patients; a significant relationship between commission errors in the Stop Signal Task and attentional impulsiveness was found. Moreover, no difference in set-shifting abilities was found comparing all clinician groups and HC. So our results indicated no cognitive impairment in these two cognitive functions in BN patients, while AN and BN showed different performances in motor inhibition. A similar cognitive profile was found in other obsessive compulsive spectrum disorders. Finally, the paper suggests a new interactive approach for the study of cognitive profile in psychiatric disorders; it might be more useful since it is more closely related to the executive functions complexity.

Effects of gender and executive function on visuospatial working memory in adult obsessive–compulsive disorder

Visuospatial working memory (VSWM) is the ability of the brain to transiently store and manipulate visual information. VSWM deficiencies have been reported in obsessive–compulsive disorder (OCD), but not consistently, perhaps due to variability in task design and clinical patient factors. To explore this variability, this study assessed effects of the design factors task difficulty and executive organizational strategy and of the clinical factors gender, OCD symptom dimension, and duration of illness on VSWM in OCD. The CANTAB spatial working memory, spatial recognition memory, delayed matching to sample, and stop signal tasks were administered to 42 adult OCD patients and 42 age- and sex-matched healthy controls. Aims were to detect a possible VSWM deficit in the OCD sample, to evaluate influences of the above task and patient factors, to determine the specificity of the deficit to the visuospatial subdomain, and to examine effects of sustained attention as potential neurocognitive confound. We confirmed previous findings of a VSWM deficit in OCD that was more severe for greater memory load (task difficulty) and that was affected by task strategy (executive function). We failed to demonstrate significant deficits in neighboring or confounding neurocognitive subdomains (visual object recognition or visual object short-term memory, sustained attention). Notably, the VSWM deficit was only significant for female patients, adding to evidence for sexual dimorphism in OCD. Again as in prior work, more severe OCD symptoms in the symmetry dimension (but no other dimension) significantly negatively impacted VSWM. Duration of illness had no significant effect on VSWM. VSWM deficits in OCD appear more severe with higher task load and may be mediated through poor task strategy. Such deficits may present mainly in female patients and in (male and female) patients with symmetry symptoms.

Planning functioning and impulsiveness in obsessive–compulsive disorder

Planning ability (PA) is a key aspect of cognitive functioning and requires subjects to identify and organise the necessary steps to achieve a goal. Despite the central role of executive dysfunction in patients with obsessive–compulsive disorder (OCD), deficits in PA have been investigated leading to contrasting results. Given these inconsistencies, the main aim of our work is to give a deeper and clearer understanding of PA in OCD patients. Moreover, we are interested in investigating the relationship between PAs and impulsivity traits and other clinical variables. Sixty-eight OCD patients and 68 healthy controls (HCs) matched for sex and age were assessed through the Stocking of Cambridge (SoC), a computerised version of the Tower of London. We examined planning sub-components for each difficulty levels (from 2 to 5 minimum moves). Our results showed that OCD patients needed longer initial thinking time than HCs during the execution of low demanding tasks (i.e. 2 and 3 moves), while the accuracy level between the two groups did not significantly differ. OCD patients required longer initial thinking time also during high demanding tasks (i.e., 4 and 5 moves), but in this case their accuracy was significantly worse than HCs’ one. We did not find any association between impulsivity and PAs. Our results supported the hypothesis that OCD patients were not able to retain in memory the planned sequence and they had to reschedule their movements during the execution. Thus, future studies should deepen the interrelation between working memory and PA to better understand the influence between these two cognitive functions and their interaction with clinical variables in OCD patients.

Validating the Italian Version of the Disgust and Propensity Scale-Revised

The aim of this work is to evaluate the factor structure and psychometric properties of the Italian version of the Disgust Propensity and Sensitivity Scale-Revised (DPSS-R, 16 items) in two samples taken from the general population. In the first study, 285 participants completed the DPSS-R questionnaire through a web-based survey. Exploratory factor analysis for ordinal Likert-type data supported the existence of four underlying factors, reflecting self-focused disgust, disgust propensity, somatic anxiety and disgust sensitivity. In the second study, an independent sample of 293 participants was enrolled as a test set to validate the factor structure obtained in the exploratory phase. The factor solution was confirmed, but showed quite highly correlated latent factors. We fitted the model and tested whether or not the bifactor structure was better than the previous one (four correlated factors). Actually, we had evidence supporting the presence of a general factor, providing a measure of disgust susceptibility, along with the four specific factors previously defined. This result could be useful also from the clinical perspective since the DPSS-R questionnaire will be used in clinical context, where underlying factors may be related to different and specific psychopathological profiles. Finally, we examined and visualized the interrelationships among the four DPSS-R factors and the external scales (Anxiety Sensitivity, Disgust Scale and Padua) using a graphical model approach.

Low baseline startle in anorexia nervosa patients

This study examined baseline startle magnitude, using eye blink response and skin conductance response in anorexia nervosa patients. Twenty female in-patients with anorexia nervosa and an equal number of female healthy controls were tested. Baseline startle response was assessed during blank screens while four startling loud sounds (a 116 dB, 1s, 250 Hz tone) were delivered with a time interval ranging from 35 to 55 s. It was investigated if BMI and state anxiety correlated with physiological responses. The clinical sample showed a lower baseline startle reflex measured with both indices, than healthy controls. Across the whole sample, a single regression model partially explained the relationship between BMI and baseline skin conductance response.

Integrating Dimensional and Discrete Theories of Emotions: A New Set of Anger- and Fear-Eliciting Stimuli for Children

ABSTRACT The selection of appropriate stimuli for inducing specific emotional states has become one of the most challenging topics in psychological research. In the literature there is a lack of affective picture database specifically suited to investigate emotional response in children. Here the authors present the methodology that led us to create a new database (called Anger- and Fear-Eliciting Stimuli for Children) of affective stimuli inducing experiences of 3 target emotions (neutral, anger, and fear) to use in experimental session involving children. A total of 84 children were asked to (a) indicate the perceived emotion and its intensity and (b) rate the three affective dimensions of the Self-Assessment Manikin (SAM). Based on concordance between labeled and expected target emotion, the authors decided to select 15 stimuli to be included in Multivariate modeling techniques were applied to evaluate the association between expected target emotion and SAM ratings. The authors found that the hit rate for the neutral pictures was good (greater than 81%), for fear-eliciting pictures it was greater than 64%, and for anger-eliciting pictures it was moderate (between 45% and 56%). The study results reveal also an age effect only in the arousal scale. However, the authors did not find significant gender-related differences in SAM ratings.

Exploring and integrating discrete and dimensional approaches while inducing negative emotional states

Abstract Selecting visual stimuli for inducing specific emotional states is very challenging, since the choice relies on specific conceptualization of emotions. In this work, we present a set of 55 stimuli, realized integrating discrete and dimensional theories of emotions, and specifically selected to investigate anger, fear, and disgust reactions in non-clinical and clinical contexts. Our set of stimuli presents several aspects of novelty since (1) a large and heterogeneous sample of subjects from the general population was involved in the labelling task, and (2) bivariate and multivariate statistical techniques were applied to integrate emotion models. The proposed set of stimuli could be useful for researchers and other professionals in the affective sciences to address negative emotion recognition issues within a broader perspective both in general population and in psychiatric samples. The obtained comprehensive characterization of the stimuli allowed us to confirm the sexual dimorphism in emotional processing.

Who Has Done It? Exploring Gaze Agency in Obsessive-Compulsive Checkers

The sense of agency (SoA) is a multifaceted construct, which can be defined as the ability to understand the causal relationships between our actions and sensory events. Obsessive-Compulsive Disorder (OCD) patients with checking compulsions often report a “lack of action completion” sensations, which has been conceptualized in the so-called “Not Just Right Experiences” construct. An intriguing explanation of this phenomenon comes from Belayachi and Van der Linden (2009, 2010), who suggest that OCD-checking patients are more prone to specify their action in a relatively molecular and inflexible way. Currently, there are no studies in literature which address this issue in OCD patients, except for the one of Gentsch et al. (2012), who suggested an altered SoA in these patients. Here we exploited a novel construct, gaze agency, to evaluate causal attribution capabilities in a group of 21 OCD patients (checkers) and matched healthy controls (HCs). Basically, two tasks targeted observers’ capability to identify their own eye movements as the cause of concurrently presented beeps, which allowed us to measure agency sensitivity as well as subtle agency alterations in an ecological setting. We found a poorer performance in OCD patients as compared to HCs in many parameters of our tasks, suggesting a difficulty with causal attribution possibly due to both a reduced cognitive flexibility and a less functional gaze agency in OCD patients.