Vince Polito

Developing the Sense of Agency Rating Scale (SOARS): an empirical measure of agency disruption in hypnosis.

Two experiments report on the construction of the Sense of Agency Rating Scale (SOARS), a new measure for quantifying alterations to agency. In Experiment 1, 370 participants completed a preliminary version of the scale following hypnosis. Factor analysis revealed two underlying factors: Involuntariness and Effortlessness. In Experiment 2, this two factor structure was confirmed in a sample of 113 low, medium and high hypnotisable participants. The two factors, Involuntariness and Effortlessness, correlated significantly with hypnotisability and pass rates for ideomotor, challenge and cognitive items. Twelve week test-retest correlations showed that Involuntariness was highly stable, but Effortlessness only moderately stable. Analysis of the combined datasets from Experiments 1 and 2 showed both SOARS scores were significantly related to the derived factors of Woody, Barnier, and McConkeys (2005) 4-factor model of hypnotisability. This scale clarifies conceptual confusion around agentive action and provides empirical support for a multifactorial account of sense of agency.

An open clinical trial assessing a novel training program for social cognitive impairment in schizophrenia

Objective: Social cognition is profoundly impaired in patients with schizophrenia. This study describes ‘Mental-State Reasoning Training for Social Cognitive Impairment’ (SoCog-MSRT), a 5-week program developed to improve social cognition in patients with schizophrenia. We aimed to investigate the feasibility of implementing SoCog-MSRT in a rehabilitation setting and to evaluate whether our training methods produced improvements. Method The feasibility and benefits of SoCog-MSRT were evaluated in an open clinical trial with 14 participants with schizophrenia or schizoaffective disorder. Training comprised 10 twice-weekly sessions, for 5 weeks, with a pre- and post-training assessment. Results: There were significant improvements on: (a) a classic false-belief test of Theory of Mind (ToM); (b) inferring complex mental states from the eyes; and (c) a self-reported measure of social understanding. Some of these improvements were associated with baseline levels of working memory and premorbid Intelligence Quotient (IQ). Conclusions SoCog-MSRT can improve ToM abilities and social understanding, but individuals with poorer working memory and lower premorbid IQ may be less able to benefit from this type of training.

Non-hierarchical influence of visual form, touch, and position cues on embodiment, agency, and presence in virtual reality

The concept of self-representation is commonly decomposed into three component constructs (sense of embodiment, sense of agency, and sense of presence), and each is typically investigated separately across different experimental contexts. For example, embodiment has been explored in bodily illusions; agency has been investigated in hypnosis research; and presence has been primarily studied in the context of Virtual Reality (VR) technology. Given that each component involves the integration of multiple cues within and across sensory modalities, they may rely on similar underlying mechanisms. However, the degree to which this may be true remains unclear when they are independently studied. As a first step toward addressing this issue, we manipulated a range of cues relevant to these components of self-representation within a single experimental context. Using consumer-grade Oculus Rift VR technology, and a new implementation of the Virtual Hand Illusion, we systematically manipulated visual form plausibility, visual–tactile synchrony, and visual–proprioceptive spatial offset to explore their influence on self-representation. Our results show that these cues differentially influence embodiment, agency, and presence. We provide evidence that each type of cue can independently and non-hierarchically influence self-representation yet none of these cues strictly constrains or gates the influence of the others. We discuss theoretical implications for understanding self-representation as well as practical implications for VR experiment design, including the suitability of consumer-based VR technology in research settings.

Revisiting the link between body and agency: visual movement congruency enhances intentional binding but is not body-specific

Embodiment and agency are key aspects of how we perceive ourselves that have typically been associated with independent mechanisms. Recent work, however, has suggested that these mechanisms are related. The sense of agency arises from recognising a causal influence on the external world. This influence is typically realised through bodily movements and thus the perception of the bodily self could also be crucial for agency. We investigated whether a key index of agency – intentional binding – was modulated by body-specific information. Participants judged the interval between pressing a button and a subsequent tone. We used virtual reality to manipulate two aspects of movement feedback. First, form: participants viewed a virtual hand or sphere. Second, movement congruency: the viewed object moved congruently or incongruently with the participant’s hidden hand. Both factors, form and movement congruency, significantly influenced embodiment. However, only movement congruency influenced intentional binding. Binding was increased for congruent compared to incongruent movement feedback irrespective of form. This shows that the comparison between viewed and performed movements provides an important cue for agency, whereas body-specific visual form does not. We suggest that embodiment and agency mechanisms both depend on comparisons across sensorimotor signals but that they are influenced by distinct factors.

Belief, delusion, hypnosis, and the right dorsolateral prefrontal cortex: a transcranial magnetic stimulation study

According to the Two-Factor theory of delusional belief (see e.g. Coltheart at al., 2011), there exists a cognitive system dedicated to the generation, evaluation, and acceptance or rejection of beliefs. Studies of the neuropsychology of delusion provide evidence that this system is neurally realized in right dorsolateral prefrontal cortex (rDLPFC). Furthermore, we have shown that convincing analogues of many specific delusional beliefs can be created in nonclinical subjects by hypnotic suggestion and we think of hypnosis as having the effect of temporarily interfering with the operation of the belief system, which allows acceptance of the delusional suggestions. If the belief system does depend on rDLPFC, then disrupting the activity of that region of the brain by the application of repetitive transcranial magnetic stimulation (rTMS) will increase hypnotizability. Dienes and Hutton (2013) have reported such an experiment except that it was left DLPFC to which rTMS was applied. An effect on a subjective measure of hypnotizability was observed, but whether there was an effect on an objective measure could not be determined. We report two experiments. The first was an exact replication of the Dienes and Hutton experiment; here we found no effect of rTMS to lDLPFC on any hypnotic measure. Our second experiment used rTMS applied to right rather then left DLPFC. This right-sided stimulation enhanced hypnotizability (when hypnotic response was measured objectively), as predicted by our hypothesis. These results imply a role for rDLPFC in the cognitive process of belief evaluation, as is proposed in our two-factor theory of delusion. They are also consistent with a conception of the acceptance of a hypnotic suggestion as involving suspension of disbelief.

Hypnotic Clever Hands: agency and automatic responding

The Clever Hands task (Wegner, Fuller, & Sparrow, 2003) is a behavioral illusion in which participants make responses to a trivia quiz for which they have no sense of agency. Sixty high hypnotizable participants completed two versions of the Clever Hands task. Quiz One was a replication of the original study. Quiz Two was a hypnotic adaptation using three suggestions that were based on clinical disruptions to the sense of agency. The suggestions were for: random responding, thought insertion, and alien control. These suggestions led to differences in accuracy (action production) and estimates of accuracy (action projection). Specifically, whereas the random responding suggestion had little effect, the two clinically based suggestions had opposite impacts on action production: the thought insertion suggestion led to an increase in the rate of correct responses (although participants still believed they were responding randomly); while the alien control suggestion led to a reduction in the rate of correct answers and a pattern of results that more closely approximated randomness. Contrary to theoretical accounts that claim that hypnosis affects executive monitoring rather than executive control, this result indicates that specific hypnotic suggestions can also influence the implicit processes involved in action production.

No meditation-related changes in the auditory N1 during first-time meditation

Recent studies link meditation expertise with enhanced low-level attention, measured through auditory event-related potentials (ERPs). In this study, we tested the reliability and validity of a recent finding that the N1 ERP in first-time meditators is smaller during meditation than non-meditation - an effect not present in long-term meditators. In the first experiment, we replicated the finding in first-time meditators. In two subsequent experiments, we discovered that this finding was not due to stimulus-related instructions, but was explained by an effect of the order of conditions. Extended exposure to the same tones has been linked with N1 decrement in other studies, and may explain N1 decrement across our two conditions. We give examples of existing meditation and ERP studies that may include similar condition order effects. The role of condition order among first-time meditators in this study indicates the importance of counterbalancing meditation and non-mediation conditions in meditation studies that use event-related potentials.

Changes in the sense of agency during hypnosis: the Hungarian version of the Sense of Agency Rating Scale (SOARS-HU) and its relationship with phenomenological aspects of consciousness

Changes in the sense of agency are defining feature of hypnosis. The Sense of Agency Rating Scale (SOARS) is a 10-item questionnaire, administered after a hypnosis session to assess alteration in the sense of agency. In the present study, a Hungarian version of the measure (SOARS-HU) is presented. The SOARS-HU and the Phenomenology of Consciousness Inventory (PCI) were administered to 197 subjects following hypnotizability screening with the Harvard Group Scale of Hypnotic Susceptibility Scale, Form A (HGSHS:A). Confirmatory factor analysis and correlations with hypnotizability demonstrate the reliability and validity of the SOARS-HU. Changes in the Involuntariness and Effortlessness subscales of the SOARS-HU were associated with alterations in subjective conscious experience, as measured by the PCI. These changes in subjective experience remained significant after controlling for HGSHS:A scores. These results indicate that changes in the sense of agency during hypnosis are associated with alterations of consciousness that are independent of hypnotizability.

Social knowldge and social cognition dissociate in schizophrenia

Introduction: Longitudinal studies of women with eating disorders report variable outcomes and there are few consistent predictors of outcome. Aim: The study aims were to describe the course and putative predictors of outcome of community women with disordered eating. Method: One hundred and twenty-two young women (mean age 28.596.3 years) identified in a general population based survey (1) with eating disorder symptoms of clinical severity agreed to participate in a follow-up study. The present paper reports on results at two years. Eating disorder symptoms, health related quality of life, general psychological function, help-seeking, and defence style were assessed at baseline, and two years by questionnaire. Results: Eighty-seven women (71%) completed the two year followup. Multiple linear regression analyses were used to identify demographic and other characteristics related to the EDEQ global score and to the SF12 mental score at the two year follow-up. At two years of follow-up the mean EDEQ global score was 3.1, 59.8% of women had experienced at least one day out of role during the past four weeks, and the mean SF12 mental component score was 38.0. In the multivariate model, a higher level of immature defence style and baseline binge eating severity, significantly predicted higher levels of eating disorder symptom severity at two years. A higher level of immature defence style, higher general psychological disturbance, lower BMI, and not reporting home duties as main work, were associated with poorer quality of life. Conclusions: The relevance of defence style to personality structure and as a main predictor of outcome in women with eating disorders will be discussed. Reference 1. Mond JM, Hay PJ, Rodgers B, Owen, C. Self-recognition of disordered eating among women with bulimic-type eating disorders: a community-based study. Int J Eat Disord in press.