Direct verbal suggestibility: Measurement and significance.

Hypnotic suggestibility is part of the wider psychological trait of direct verbal suggestibility (DVS). Historically, DVS in hypnosis has informed theories of consciousness and of conversion disorder. More recently it has served as a research tool in cognitive science and in cognitive neuroscience in particular. Here we consider DVS as a general trait, its relation to other psychological characteristics and abilities, and to the origin and treatment of clinical conditions. We then outline the distribution of DVS in the population, its measurement, relationship to other forms of suggestibility, placebo responsiveness, personal characteristics, gender, neurological processes and other factors, such as expectancy. There is currently no scale specifically designed to measure DVS outside a hypnotic context. The most commonly used and well-researched of the hypnosis-based scales, the Harvard Group Scale, is described and identified as a basis for a more broadly based measure of DVS for use in psychological research.

Rivermead assessment of somatosensory performance: Italian normative data.

The Rivermead assessment of somatosensory performance (RASP) provides a quantitative assessment of somatosensory processing, suitable for brain-damaged patients suffering from stroke. It consists of seven subcomponents: Subtest 1 (sharp/dull discrimination), Subtest 2 (surface pressure touch), Subtest 3 (surface localization), Subtest 4 (sensory extinction), Subtest 5 (2-point discrimination), Subtest 6 (temperature discrimination), and Subtest 7 (proprioception). Overall, the RASP assesses 5 bilateral body regions: face (cheek), hand (palm and back), and foot (sole and back). This study aimed at providing normative data and cut-off scores for RASP subtests, for each body region, in a large Italian population sample. We present results from 300 healthy Italian individuals aged 19 to 98 years. Data represent a comprehensive set of norms that cover each subtest and each body region tested. Performance in Subtests 1, 5, and 6 decreased, for some body regions, with increasing age. Based on these results, norms were stratified for age (seven groups), with the pathological/non-pathological cut-off coinciding with the 5th percentile. Conversely, other results were not influenced by age; in such cases, a single error, in each body region, has to be considered indicative of pathological performance. This independent investigation of all subcomponents of the somatosensory system, for each body region, further confirms RASP's potential in clinical practice, for neurological assessment, as well as in research settings.

Delusions and theories of belief.

Cognitive neuropsychiatry is a branch of cognitive psychology that seeks to explain neuropsychiatric symptoms in terms of disruptions or damage to normal cognitive processes. A key objective of this approach is to use insights derived from the study of pathological symptoms to inform accounts of premorbid cognitive systems. Delusions, in particular, can be considered to represent dysfunction of the cognitive processes underlying belief formation, so studying delusions may provide unique insights into nonpathological belief. While this approach has provided compelling accounts for a range of delusions in terms of putative cognitive dysfunctions, it is less clear that it has achieved progress in its reciprocal goal of informing understanding of belief more generally. In this review, we trace the origins of the cognitive neuropsychiatric approach and consider the reasons for the lack of progress. We propose a tentative framework to overcome these challenges and suggest directions for future research.

Hypnotic suggestion: opportunities for cognitive neuroscience.

Hypnosis uses the powerful effects of attention and suggestion to produce, modify and enhance a broad range of subjectively compelling experiences and behaviours. For more than a century, hypnotic suggestion has been used successfully as an adjunctive procedure to treat a wide range of clinical conditions. More recently, hypnosis has attracted a growing interest from a cognitive neuroscience perspective. Recent studies using hypnotic suggestion show how manipulating subjective awareness in the laboratory can provide insights into brain mechanisms involved in attention, motor control, pain perception, beliefs and volition. Moreover, they indicate that hypnotic suggestion can create informative analogues of clinical conditions that may be useful for understanding these conditions and their treatments.

The biopsychosocial model of illness: a model whose time has come.

The biopsychosocial model outlined in Engel's classic Science paper four decades ago emerged from dissatisfaction with the biomedical model of illness, which remains the dominant healthcare model. Engel's call to arms for a biopsychosocial model has been taken up in several healthcare fields, but it has not been accepted in the more economically dominant and politically powerful acute medical and surgical domains. It is widely used in research into complex healthcare interventions, it is the basis of the World Health Organisation's International Classification of Functioning (WHO ICF), it is used clinically, and it is used to structure clinical guidelines. Critically, it is now generally accepted that illness and health are the result of an interaction between biological, psychological, and social factors. Despite the evidence supporting its validity and utility, the biopsychosocial model has had little influence on the larger scale organization and funding of healthcare provision. With chronic diseases now accounting for most morbidity and many deaths in Western countries, healthcare systems designed around acute biomedical care models are struggling to improve patient-reported outcomes and reduce healthcare costs. Consequently, there is now a greater need to apply the biopsychological model to healthcare management. The increasing proportion of healthcare resource devoted to chronic disorders and the accompanying need to improve patient outcomes requires action; better understanding and employment of the biopsychosocial model by those charged with healthcare funding could help improve healthcare outcome while also controlling costs.

Factitious disorders and malingering: challenges for clinical assessment and management.

Compared with other psychiatric disorders, diagnosis of factitious disorders is rare, with identification largely dependent on the systematic collection of relevant information, including a detailed chronology and scrutiny of the patient's medical record. Management of such disorders ideally requires a team-based approach and close involvement of the primary care doctor. As deception is a key defining component of factitious disorders, diagnosis has important implications for young children, particularly when identified in women and health-care workers. Malingering is considered to be rare in clinical practice, whereas simulation of symptoms, motivated by financial rewards, is regarded as more common in medicolegal settings. Although psychometric investigations (eg, symptom validity testing) can inform the detection of illness deception, such tests need support from converging evidence sources, including detailed interview assessments, medical notes, and relevant non-medical investigations. A key challenge in any discussion of abnormal health-care-seeking behaviour is the extent to which a person's reported symptoms are considered to be a product of choice, or psychopathology beyond volitional control, or perhaps both. Clinical skills alone are not typically sufficient for diagnosis or to detect malingering. Medical education needs to provide doctors with the conceptual, developmental, and management frameworks to understand and deal with patients whose symptoms appear to be simulated. Central to the understanding of factitious disorders and malingering are the explanatory models and beliefs used to provide meaning for both patients and doctors. Future progress in management will benefit from an increased appreciation of the contribution of non-medical factors and a greater awareness of the conceptual and clinical findings from social neuroscience, occupational health, and clinical psychology.

Delusions in postpartum Psychosis: Implications for cognitive theories.

Postpartum psychosis is a rare but serious condition that can affect women after childbirth. We present a case study of an individual with no comorbidities or psychiatric history who developed postpartum psychosis characterised by prominent misidentification delusions whilst admitted to hospital. The woman recovered quickly with medication and showed no evidence of relapse over the following three years. Whilst still symptomatic and after recovery, the patient was able to provide a detailed description of her experiences. Contemporaneous interviews and observations during her hospital admission and a subsequent detailed retrospective account provide a unique, comprehensive window into her experience of these time-limited delusions. Her case reveals important insights including the triggers for her misidentification delusions, the role of social and contextual influences on delusional beliefs, and her recall of active involvement in evaluating and discarding delusional hypotheses. These insights highlight the complexity of delusional beliefs, challenge existing theories of delusions, and help inform broader theories of belief formation.

Hypnosis and suggestion as interventions for functional neurological disorder: A systematic review.

OBJECTIVE: Functional neurological disorder (FND) involves the presence of neurological symptoms that cannot be explained by neurological disease. FND has long been linked to hypnosis and suggestion, both of which have been used as treatments. Given ongoing interest, this review examined evidence for the efficacy of hypnosis and suggestion as treatment interventions for FND. METHOD: A systematic search of bibliographic databases was conducted to identify group studies published over the last hundred years. No restrictions were placed on study design, language, or clinical setting. Two reviewers independently assessed papers for inclusion, extracted data, and rated study quality. RESULTS: The search identified 35 studies, including 5 randomised controlled trials, 2 non-randomised trials, and 28 pre-post studies. Of 1584 patients receiving either intervention, 1379 (87%) showed significant improvements, including many who demonstrated resolution of their symptoms in the short-term. Given the heterogeneity of interventions and limitations in study quality overall, more formal quantitative synthesis was not possible. CONCLUSIONS: The findings highlight longstanding and ongoing interest in using hypnosis and suggestion as interventions for FND. While the findings appear promising, limitations in the evidence base, reflecting limitations in FND research more broadly, prevent definitive recommendations. Further research seems warranted given these supportive findings.

Dissociation in hysteria and hypnosis: evidence from cognitive neuroscience.

Jean-Martin Charcot proposed the radical hypothesis that similar brain processes were responsible for the unexplained neurological symptoms of 'hysteria', now typically diagnosed as 'conversion disorder' or 'dissociative (conversion) disorder', and the temporary effects of hypnosis. While this idea has been largely ignored, recent cognitive neuroscience studies indicate that (i) hypnotisability traits are associated with a tendency to develop dissociative symptoms in the sensorimotor domain; (ii) dissociative symptoms can be modelled with suggestions in highly hypnotisable subjects; and (iii) hypnotic phenomena engage brain processes similar to those seen in patients with symptoms of hysteria. One clear theme to emerge from the findings is that 'symptom' presentation, whether clinically diagnosed or simulated using hypnosis, is associated with increases in prefrontal cortex activity suggesting that intervention by the executive system in both automatic and voluntary cognitive processing is common to both hysteria and hypnosis. Nevertheless, while the recent literature provides some compelling leads into the understanding of these phenomena, the field still lacks well controlled systematically designed studies to give a clear insight into the neurocognitive processes underlying dissociation in both hysteria and hypnosis. The aim of this review is to provide an agenda for future research.

Correlates of perceptual distortions in clinical and non-clinical populations using the Cardiff Anomalous Perceptions Scale (CAPS): associations with anxiety and depression and a re-validation using a representative population sample.

Although the literature on hallucinations in psychiatric patients shows clear links with anxiety and depression, associations of affect with a wider array of anomalous perceptual experiences have been much less studied. This study investigated patients with psychosis (N=29) and a non-clinical population (N=193) using the Cardiff Anomalous Perceptions Scale (CAPS), a measure of perceptual distortion and associated distress, intrusiveness and frequency; along with measures of depression, anxiety and worry. The study also allowed a re-validation of the CAPS in a more representative sample of the UK population. Moderate, reliable correlations with depression, anxiety and worry were found in the non-clinical population with the association being stronger in psychotic patients. The study re-confirmed that anomalous perceptual experiences are common in the general population and that a significant minority (11.9%) have higher levels than the mean of psychotic patients. Scale reliability and validity were also re-confirmed, and the CAPS score was found to be unrelated to age or gender in either sample. As in the original study, factor analysis produced a three-factor solution, although factor theme was not fully replicated: as before, a cluster of first-rank symptoms emerged, but with equivocal evidence for a temporal lobe factor and no replication of a 'chemosensation' component.

Using hypnosis to gain insights into healthy and pathological cognitive functioning.

The demonstration that hypnotic suggestion can inhibit word/colour Stroop highlights one of the benefits of using hypnosis to explore cognitive psychology and in particular attentional processes. The compelling results using a rigorous design have particular relevance for the presumed automaticity of some forms of information processing. Moreover the results support the potential that hypnotic suggestion offers for creating clinically informed analogues of relevant psychological and neuropsychological conditions. As with all novel research, the results of Raz and Campbell raise further operational and theoretical questions, relating in this case to the use of hypnotic, post-hypnotic and non-hypnotic suggestion and the utility of existing measures of hypnotizability.

The prevalence of delusion-like beliefs relative to sociocultural beliefs in the general population.

BACKGROUND: Delusions are defined as false beliefs different from those that almost everyone else believes. The aim was to develop a new measure (the Cardiff Beliefs Questionnaire, CBQ) to establish the range and prevalence of delusion-like beliefs (DLB) and compare these to other types of beliefs in the general population. SAMPLING AND METHODS: A total of 1,000 participants completed the CBQ, which uniquely assesses a broader range of currently held beliefs [delusion-like (bizarre and non-bizarre), paranormal and religious and general political/social beliefs) using this large stratified sample. RESULTS: Strong belief in 1 or more DLB was reported by 39% of the participants (91% reporting 'weak', 'moderate' or 'strong' belief in at least 1 DLB). Moreover, 25% endorsed at least 1 bizarre DLB (76% one or more at any strength). Endorsements of DLB were strongly correlated with paranormal and religious beliefs but not general political/social beliefs. CONCLUSIONS: Both bizarre and non-bizarre DLB are frequently found in the general population, lending support to the psychosis continuum account and need to revise key clinical criteria used to diagnose delusions. The good psychometric properties demonstrated by the CBQ indicate that this measure is a useful tool to investigate the wider continuum of beliefs held in the general population.

Giving Up on Consciousness as the Ghost in the Machine.

Consciousness as used here, refers to the private, subjective experience of being aware of our perceptions, thoughts, feelings, actions, memories (psychological contents) including the intimate experience of a unified self with the capacity to generate and control actions and psychological contents. This compelling, intuitive consciousness-centric account has, and continues to shape folk and scientific accounts of psychology and human behavior. Over the last 30 years, research from the cognitive neurosciences has challenged this intuitive social construct account when providing a neurocognitive architecture for a human psychology. Growing evidence suggests that the executive functions typically attributed to the experience of consciousness are carried out competently, backstage and outside subjective awareness by a myriad of fast, efficient non-conscious brain systems. While it remains unclear how and where the experience of consciousness is generated in the brain, we suggested that the traditional intuitive explanation that consciousness is causally efficacious is wrong-headed when providing a cognitive neuroscientific account of human psychology. Notwithstanding the compelling 1st-person experience (inside view) that convinces us that subjective awareness is the mental curator of our actions and thoughts, we argue that the best framework for building a scientific account is to be consistent with the biophysical causal dependency of prior neural processes. From a 3rd person perspective, (outside view), we propose that subjective awareness lacking causal influence, is (no more) than our experience of being aware, our awareness of our psychological content, knowing that we are aware, and the belief that that such experiences are evidence of an agentive capacity shared by others. While the human mind can be described as comprising both conscious and nonconscious aspects, both ultimately depend on neural process in the brain. In arguing for the counter-intuitive epiphenomenal perspective, we suggest that a scientific approach considers all mental aspects of mind including consciousness in terms of their underlying, preceding (causal) biological changes, in the realization that most brain processes are not accompanied by any discernible change in subjective awareness.

Hypnotic suggestion and cognitive neuroscience.

The growing acceptance of consciousness as a legitimate field of enquiry and the availability of functional imaging has rekindled research interest in the use of hypnosis and suggestion to manipulate subjective experience and to gain insights into healthy and pathological cognitive functioning. Current research forms two strands. The first comprises studies exploring the cognitive and neural nature of hypnosis itself. The second employs hypnosis to explore known psychological processes using specifically targeted suggestions. An extension of this second approach involves using hypnotic suggestion to create clinically informed analogues of established structural and functional neuropsychological disorders. With functional imaging, this type of experimental neuropsychopathology offers a productive means of investigating brain activity involved in many symptom-based disorders and their related phenomenology.

Contralateral stimulation, using TENS, of phantom limb pain: two confirmatory cases.

OBJECTIVES: This study aims to evaluate the effectiveness of trans-electric nerve stimulation (TENS) for phantom limb pain applied to contralateral limb (nonamputated limb). DESIGN: Two detailed single case studies using TENS on the contralateral limb are reported in a longitudinal study with one-year follow-up. Five variables were measured across this period. The study comprised of five sequential stages (Pre-assessment, Preliminary baseline, Start of intervention, Extended assessment, One-year follow-up). SETTING AND PATIENTS: Patients were identified at the Rookwood Hospital in Cardiff. They subsequently received regular home visits. The first patient was a 24-year-old male who had suffered a left below-elbow amputation following a car crash. The second patient was a 38-year-old male who had a transfemoral right amputation further to a viral infection. MEASURES: The following semistructured interview and questionnaires were used: McGill Comprehensive pain questionnaire part A and B; The Cambridge Phantom Limb Profile; The Groningen Questionnaire: Problems after Arm Amputation; and 13 Visual Analog Scales. CONCLUSIONS: Both patients showed a significant improvement in their perception of phantom limb pain and sensations that was maintained at one-year follow-up. A randomized blinded controlled trial to confirm these positive outcomes is required.

UNITED KINGDOM NORMS FOR THE HARVARD GROUP SCALE OF HYPNOTIC SUSCEPTIBILITY, FORM A.

The Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A), is widely used as a measure of suggestibility to screen participants for research purposes. To date, there have been a number of normative studies of the HGSHS:A, the majority of which originate from Western countries. The outcomes of these Western studies are summarized, and variations in methodologies are described and discussed. Also reported are the psychometric properties of the HGSHS:A in a large contemporary United Kingdom (UK) sample. Overall, these UK results are consistent with the earlier Western norms studies in terms of response distribution and item difficulty, with only minor differences. The continued use of HGSHS:A as a screening procedure is supported, particularly if corrected for response subjectivity/involuntariness and with revised amnesia scoring. The HGSHS:A is also important as a potential measure of the broader trait of direct verbal suggestibility.

Line bisection: does introspection inform cognitive strategy?

Line bisection is widely used to diagnose and quantify hemispatial neglect, yet there is little consensus as to the cognitive mechanisms used to perform this simple task. Current cognitive accounts have been deduced solely from behavioural measures. The aim of this study was to discover if subject's own knowledge of the mental strategies used to perform the task actually informs behavioural performance. One hundred and forty healthy volunteers bisected a set of lines and were asked to describe the mental strategies used. Three distinct strategies were identified. These were (1) comparing two segments, (2) computing the centre of mass, and (3) externally centred strategies. Strategies 1 and 2 have previously been described but externally centred strategies have not been reported as a distinct strategy in bisection. Although none of the three strategies predicted performance this may have been due to the fact that 44% of subjects failed to describe any strategy. Men and women bisected lines equally well, however more men than women reported use of externally centred strategies.

Are anomalous perceptual experiences necessary for delusions?

Several theories of delusions suggest that anomalous perceptual experience is necessary for delusion formation. This study evaluated levels of anomalous perceptual experience in a large group of nonclinical participants from the general population (N = 337), a group of psychotic inpatients (N = 20), and 2 groups of hallucinating (N = 24) and nonhallucinating (N = 24) deluded patients. The aims of the study were to evaluate the hypothesis that pathological levels of anomalous perceptual experience were necessarily associated with delusions. Using the Cardiff Anomalous Perceptions Scale, the main finding was that as a group, nonhallucinating deluded patients were not significantly different from nonclinical participants on any of the anomalous perceptual experience indices. We conclude that anomalous perceptual experience, as measured by the Cardiff Anomalous Perceptions Scale, is not necessary for the presence of delusions.

Comparative measures of represented linear extent: implications for clinical assessment.

Although line copying provides a simple and direct perceptual estimate of linear extent, line bisection is the most common clinical test traditionally used to quantify visuospatial neglect. This study aimed to establish whether the two tasks tap similar aspects of linear extent and determine which approximates actual stimulus length. One hundred and forty healthy controls were tested. Misrepresentations when copying were more than double those misrepresentations when bisecting, suggesting that the task demands involved in bisection may be less demanding than those involved in copying. Moreover, bisection performance provided the best approximation to the stimulus length used. It is suggested that the (midpoint) computational requirement of bisection facilitates a more accurate representation of linear extent by engaging implicit cues within the task. The fact that line bisection provides for a more accurate measure of represented linear extent attests to its value as a clinical test for patients with visuospatial neglect.

Explaining delusions: a cognitive perspective.

There is now considerable evidence for reasoning, attention, metacognition and attribution biases in delusional patients. Recently, these findings have been incorporated into a number of cognitive models that aim to explain delusion formation, maintenance and content. Although delusions are commonly conceptualized as beliefs, not all models make reference to models of normal belief formation. This review considers those models that explain delusions as a breakdown of normal belief formation (belief-positive models), approaches that explain the pathology only (belief-negative models) and approaches that view delusions as one end of a distribution of anomalous mental phenomena (the continuum view). A cognitive theory that includes the 'pragmatic pathology' of delusions will be able to address both the phenomenology and the treatment of delusion-related distress.