Francesca Ferri

A sensorimotor network for the bodily self

Neuroscientists and philosophers, among others, have long questioned the contribution of bodily experience to the constitution of self-consciousness. Contemporary research answers this question by focusing on the notions of sense of agency and/or sense of ownership. Recently, however, it has been proposed that the bodily self might also be rooted in bodily motor experience, that is, in the experience of oneself as instantiating a bodily structure that enables a specific range of actions. In the current fMRI study, we tested this hypothesis by making participants undergo a hand laterality judgment task, which is known to be solved by simulating a motor rotation of ones own hand. The stimulus to be judged was either the participants own hand or the hand of a stranger. We used this task to investigate whether mental rotation of pictures depicting ones own hands leads to a different activation of the sensorimotor areas as compared with the mental rotation of pictures depicting anothers hand. We revealed a neural network for the general representation of the bodily self encompassing the SMA and pre-SMA, the anterior insula, and the occipital cortex, bilaterally. Crucially, the representation of ones own dominant hand turned out to be primarily confined to the left premotor cortex. Our data seem to support the existence of a sense of bodily self encased within the sensorimotor system. We propose that such a sensorimotor representation of the bodily self might help us to differentiate our own body from that of others.

Social Requests and Social Affordances: How They Affect the Kinematics of Motor Sequences during Interactions between Conspecifics

The present study aimed at determining whether and what factors affect the control of motor sequences related to interactions between conspecifics. Experiment 1 demonstrated that during interactions between conspecifics guided by the social intention of feeding, a social affordance was activated, which modified the kinematics of sequences constituted by reaching-grasping and placing. This was relative to the same sequence directed to an inanimate target. Experiments 2 and 4 suggested that the related-to-feeding social request emitted by the receiver (i.e. the request gesture of mouth opening) is prerequisite in order to activate a social affordance. Specifically, the two experiments showed that the social request to be fed activated a social affordance even when the sequences directed towards a conspecific were not finalized to feed. Experiment 3 showed that moving inside the peripersonal space of a conspecific, who did not produce any social request, marginally affected the sequence. Finally, experiments 5 and 6 indicated that the gaze of a conspecific is necessary to make a social request effective at activating a social affordance. Summing up, the results of the present study suggest that the control of motor sequences can be changed by the interaction between giver and receiver: the interaction is characterized by a social affordance that the giver activates on the basis of social requests produced by the receiver. The gaze of the receiver is a prerequisite to make a social request effective.

The body beyond the body: expectation of a sensory event is enough to induce ownership over a fake hand

More than 100 papers have been published on the rubber hand illusion since its discovery 14 years ago. The illusion has been proposed as a demonstration that the body is distinguished from other objects by its participation in specific forms of intermodal perceptual correlation. Here, we radically challenge this view by claiming that perceptual correlation is not necessary to produce the experience of this body as mine. Each of 15 participants was seated with his/her right arm resting upon a table just below another smaller table. Thus, the real hand was hidden from the participants view and a life-sized rubber model of a right hand was placed on the small table in front of the participant. The participant observed the experimenters hand while approaching—without touching—the rubber hand. Phenomenology of the illusion was measured by means of skin conductance response and questionnaire. Both measures indicated that participants experienced the illusion that the experimenters hand was about to touch their hidden hand rather than the rubber hand, as if the latter replaced their own hand. This did not occur when the rubber hand was rotated by 180° or replaced by a piece of wood. This illusion indicates that our brain does not build a sense of self in a merely reactive way, via perceptual correlations; rather it generates predictions on what may or may not belong to itself.

Update on the Adverse Effects of Clozapine: Focus on Myocarditis

Clozapine, an atypical antipsychotic, is a dibenzodiazepine derivative and its therapeutic effects are probably mediated by dopaminergic and serotonergic activity. In accordance to several studies, it appears to be the most effective antipsychotic drug for treatment-resistant schizophrenia. Moreover, clozapine appears to be particularly beneficial in patients with schizophrenia who are suicidal and in those with comorbid substance use disorder. However, despite its efficacy, the general use of clozapine in clinical practice is somewhat limited because of the risk of several serious adverse effects such as agranulocytosis and thromboembolism. Clozapine may be associated with fatal myocarditis and cardiomyopathy in physically healthy young adults. Consequently, the FDA and the drugs manufacturer have strengthened warnings to include that a potentially fatal myocarditis may occur when taking clozapine. In the present paper the literature on clozapine-related myocardis will be reviewed and practical advice will be given concerning the diagnosis and management of such potentially fatal adverse effect.

Functional connectivity and neuronal variability of resting state activity in bipolar disorder—reduction and decoupling in anterior cortical midline structures

Introduction: The cortical midline structures seem to be involved in the modulation of different resting state networks, such as the default mode network (DMN) and salience network (SN). Alterations in these systems, in particular in the perigenual anterior cingulate cortex (PACC), seem to play a central role in bipolar disorder (BD). However, the exact role of the PACC, and its functional connections to other midline regions (within and outside DMN) still remains unclear in BD. Methods: We investigated functional connectivity (FC), standard deviation (SD, as a measure of neuronal variability) and their correlation in bipolar patients (n = 40) versus healthy controls (n = 40), in the PACC and in its connections in different frequency bands (standard: 0.01–0.10 Hz; Slow‐5: 0.01–0.027 Hz; Slow‐4: 0.027–0.073 Hz). Finally, we studied the correlations between FC alterations and clinical‐neuropsychological parameters and we explored whether subgroups of patients in different phases of the illness present different patterns of FC abnormalities. Results: We found in BD decreased FC (especially in Slow‐5) from the PACC to other regions located predominantly in the posterior DMN (such as the posterior cingulate cortex (PCC) and inferior temporal gyrus) and in the SN (such as the supragenual anterior cingulate cortex and ventrolateral prefrontal cortex). Second, we found in BD a decoupling between PACC‐based FC and variability in the various target regions (without alteration in variability itself). Finally, in our subgroups explorative analysis, we found a decrease in FC between the PACC and supragenual ACC (in depressive phase) and between the PACC and PCC (in manic phase). Conclusions: These findings suggest that in BD the communication, that is, information transfer, between the different cortical midline regions within the cingulate gyrus does not seem to work properly. This may result in dysbalance between different resting state networks like the DMN and SN. A deficit in the anterior DMN‐SN connectivity could lead to an abnormal shifting toward the DMN, while a deficit in the anterior DMN‐posterior DMN connectivity could lead to an abnormal shifting toward the SN, resulting in excessive focusing on internal contents and reduced transition from idea to action or in excessive focusing on external contents and increased transition from idea to action, respectively, which could represent central dimensions of depression and mania. If confirmed, they could represent diagnostic markers in BD. Hum Brain Mapp 36:666–682, 2015.

Is There a Nonadditive Interaction Between Spontaneous and Evoked Activity? Phase-Dependence and Its Relation to the Temporal Structure of Scale-Free Brain Activity

Abstract The aim of our study was to use functional magnetic resonance imaging to investigate how spontaneous activity interacts with evoked activity, as well as how the temporal structure of spontaneous activity, that is, long‐range temporal correlations, relate to this interaction. Using an extremely sparse event‐related design (intertrial intervals: 52‐60 s), a novel blood oxygen level‐dependent signal correction approach (accounting for spontaneous fluctuations using pseudotrials) and phase analysis, we provided direct evidence for a nonadditive interaction between spontaneous and evoked activity. We demonstrated the discrepancy between the present and previous observations on why a linear superposition between spontaneous and evoked activity can be seen by using co‐occurring signals from homologous brain regions. Importantly, we further demonstrated that the nonadditive interaction can be characterized by phase‐dependent effects of spontaneous activity, which is closely related to the degree of long‐range temporal correlations in spontaneous activity as indexed by both power‐law exponent and phase‐amplitude coupling. Our findings not only contribute to the understanding of spontaneous brain activity and its scale‐free properties, but also bear important implications for our understanding of neural activity in general.

Alexithymia and Suicide Ideation in a Sample of Patients with Binge Eating Disorder

Objective. The goal of this cross-sectional study was to evaluate the relationships between alexithymia and suicide ideation in 80 adult outpatients with a DSM-IV diagnosis of binge eating disorder (BED). Methods. Alexithymia was measured with the 20-item Toronto Alexithymia Scale (TAS-20); suicide ideation was assessed with the Scale of Suicide Ideation (SSI); severity of BED was assessed with the Binge Eating Scale (BES); and depressive and anxiety symptoms were evaluated, respectively, with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Anxiety Rating Scale (Ham-A). Results. Prevalence of current suicide ideation was 27.5% (n=22) in this sample and 10 subjects (12.5%) had attempted suicide at some time in their lives. Subjects with alexithymia had more significant suicide ideation, a higher prevalence of current suicide ideation, and more previous suicide attempts than those without alexithymia. In a linear regression model, higher MADRS scores and higher scores on the Difficulty in Identifying Feelings/Difficulty in Describing Feelings dimensions of the TAS-20 were associated with increased suicide ideation. Discussion. Suicidal behavior is no less common in BED than in other eating disorders. Individuals with BED may show increased suicide ideation, especially in the presence of alexithymia and depressive symptoms, even if these symptoms are subclinical. The authors also discuss limitations of this study and future research needs. (Journal of Psychiatric Practice 2012;18:5–11)

To me or to you? When the self is advantaged.

The present study aimed at verifying whether and why sequences of actions directed to oneself are facilitated when compared to action sequences directed to conspecifics. In experiment 1, participants reached to grasp and brought a piece of food either to their own mouth for self-feeding or to the mouth of a conspecific for feeding. In control conditions, they executed the same sequence to place the piece of food into a mouth-like aperture in a flat container placed upon either their own mouth or the mouth of a conspecific. Kinematic analysis showed that the actions of reaching and bringing were faster when directed to the participant’s own body, especially for self-feeding. The data support the hypothesis that reaching to grasp and bringing to one’s own body and, in particular, one’s own mouth for self-feeding, form an automatic sequence, because this is the result of more frequent execution and coordination between different effectors of one’s own body, such as arm and mouth. In contrast, the same sequence directed toward a conspecific is not automatic and requires more accuracy probably because it is guided by social intentions. This hypothesis was supported by the results of control experiment 2 in which we compared the kinematics of reaching to grasp and placing the piece of food into the mouth of a conspecific (i.e. feeding) with those of reaching to grasp and placing the same piece of food into a mouth-like aperture in a human body shape (i.e. placing). Indeed, the entire sequence was slowed down during feeding when compared to placing.

Altered Brain Long-Range Functional Interactions Underlying the Link Between Aberrant Self-experience and Self-other Relationship in First-Episode Schizophrenia

Self-experience anomalies are elementary features of schizophrenic pathology. Such deficits can have a profound impact on self-other relationship, but how they are related through aberrant brain function remains poorly understood. In this functional magnetic resonance imaging (fMRI) study, we provide new evidence for a cortical link between aberrant self-experience and social cognition in first-episode schizophrenia (FES). As identified in previous studies, ventral premotor cortex (vPMC) and posterior insula (pIC) are candidate brain regions underlying disturbances in both self-experience and self-other relationship due to their processing of predominantly externally guided (vPMC; goal-oriented behavior) and internally guided (pIC; interoception) stimuli. Results from functional interaction analysis in a sample of 24 FES patients and 22 healthy controls show aberrant functional interactions (background/intrinsic connectivity) of right vPMC and bilateral pIC with posterior cingulate cortex (PCC), a midline region that has been shown central in mediating self-experience. More specifically, our results show increased functional coupling between vPMC and PCC, which positively correlated with basic symptoms (subjective self-experience disturbances). pIC showed reduced functional coupling with PCC and postcentral gyrus and increased functional interactions with anterior insula. Taken together, our results suggest an imbalance in the processing between internally and externally guided information and its abnormal integration with self-referential processing as mediated by PCC. Due to our correlation findings, we suggest this imbalance to be closely related to basic symptoms in FES and thus anomalous self-experience. The findings further disentangle the cortical basis of how self-experience anomalies may pervade the social domain.

Bodily self: an implicit knowledge of what is explicitly unknown

We tested the hypothesis that the body self-advantage, i.e., the facilitation in discriminating self versus other people’s body-effectors, is the expression of an implicit and body-specific knowledge, based mainly on the sensorimotor representation of one’s own body-effectors. Alternatively, the body self-advantage could rely on visual recognition of pictorial cues. According to the first hypothesis, using gray-scale pictures of body-parts, the body self-advantage should emerge when self-body recognition is implicitly required and should be specific for body-effectors and not for inanimate-objects. In contrast, if the self-advantage is due to a mere visual–perceptual facilitation, it should be independent of the implicit or explicit request (and could be extended also to objects). To disentangle these hypotheses, healthy participants were implicitly or explicitly required to recognize either their own body-effectors or inanimate-objects. Participants were more accurate in the implicit task with self rather than with others’ body-effectors. In contrast, the self-advantage was not found when an explicit recognition of one’s own body-effectors was required, suggesting that the body self-advantage relies upon a sensorimotor, rather than a mere visual representation of one’s own body. Moreover, the absence of both self/other and implicit/explicit effects, when processing inanimate-objects, underlines the differences between the body and other objects.