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.

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.

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.

Brain mechanisms for loss of awareness of thought and movement

Loss or reduction of awareness is common in neuropsychiatric disorders and culturally influenced dissociative phenomena but the underlying brain mechanisms are poorly understood. fMRI was combined with suggestions for automatic writing in 18 healthy highly hypnotically suggestible individuals in a within-subjects design to determine whether clinical alterations in awareness of thought and movement can be experimentally modelled and studied independently of illness. Subjective ratings of control, ownership, and awareness of thought and movement, and fMRI data were collected following suggestions for thought insertion and alien control of writing movement, with and without loss of awareness. Subjective ratings confirmed that suggestions were effective. At the neural level, our main findings indicated that loss of awareness for both thought and movement during automatic writing was associated with reduced activation in a predominantly left-sided posterior cortical network including BA 7 (superior parietal lobule and precuneus), and posterior cingulate cortex, involved in self-related processing and awareness of the body in space. Reduced activity in posterior parietal cortices may underlie specific clinical and cultural alterations in awareness of thought and movement. Clinically, these findings may assist development of imaging assessments for loss of awareness of psychological origin, and interventions such as neurofeedback.

Chasing the Rainbow: The Non-conscious Nature of Being

Despite the compelling subjective experience of executive self-control, we argue that “consciousness” contains no top-down control processes and that “consciousness” involves no executive, causal, or controlling relationship with any of the familiar psychological processes conventionally attributed to it. In our view, psychological processing and psychological products are not under the control of consciousness. In particular, we argue that all “contents of consciousness” are generated by and within non-conscious brain systems in the form of a continuous self-referential personal narrative that is not directed or influenced in any way by the “experience of consciousness.” This continuously updated personal narrative arises from selective “internal broadcasting” of outputs from non-conscious executive systems that have access to all forms of cognitive processing, sensory information, and motor control. The personal narrative provides information for storage in autobiographical memory and is underpinned by constructs of self and agency, also created in non-conscious systems. The experience of consciousness is a passive accompaniment to the non-conscious processes of internal broadcasting and the creation of the personal narrative. In this sense, personal awareness is analogous to the rainbow which accompanies physical processes in the atmosphere but exerts no influence over them. Though it is an end-product created by non-conscious executive systems, the personal narrative serves the powerful evolutionary function of enabling individuals to communicate (externally broadcast) the contents of internal broadcasting. This in turn allows recipients to generate potentially adaptive strategies, such as predicting the behavior of others and underlies the development of social and cultural structures, that promote species survival. Consequently, it is the capacity to communicate to others the contents of the personal narrative that confers an evolutionary advantage—not the experience of consciousness (personal awareness) itself.

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.

Illness related deception: social or psychiatric problem?

In this paper we question the validity of factitious disorder as a meaningful psychiatric diagnosis. When the diagnosis is used there is often the assumption that the person engaging in the ‘deception’ is not lying in the traditional sense of being deliberately misleading. Moreover, little is known about the aetiology or psychopathology underlying factitious disorder, and the legitimacy of deception as a mental disorder has been questioned. It is argued that while illness deception may be more common that hitherto assumed, factitious disorder as a distinct type of psychiatric disorder is conceptually flawed, diagnostically impractical and clinically unhelpful and should be dropped from existing nosologies.

Social roles and long-term illness: is it time to rehabilitate convalescence?

The total extent of sickness in the population has increased while disease has decreased. Being sick is a role that offers the patient many advantages both directly, in terms of being absolved from undertaking many daily activities if necessary, and indirectly, through additional financial and other resources that may be offered. Because of these advantages, it is usual for any persistent sickness to be validated by health care professionals. Moreover sick people are expected to make every effort to leave the sick state, especially to make every effort using offered advice and resources such as rehabilitative treatments. However some people are sick longer than anticipated or apparently justified. The sick role developed based on assumptions that may no longer be valid, and the extended World Health Organization's International Classification of Functioning (WHO ICF) model of illness provides a new analysis of the problem, emphasizing that sometimes sickness is caused or perpetuated by factors other than disease. Among other factors, the lack of a way out of the sick role might be one reason for increasing sickness. Therefore re-establishing convalescence as a role might facilitate people in leaving the sick role, and rehabilitation should consider promoting convalescence.

Current practice and clinical relevance of somatosensory assessment after stroke

Objective: To examine the perceived clinical relevance, current practice and knowledge of somatosensory testing in three professional groups involved in the management and rehabilitation of stroke.

Design: Structured postal questionnaire sent to therapists and doctors. Subjects: One hundred and eighty occupational therapists from the National Association of Neurological Occupational Therapists (NANOT), 180 physiotherapists from the Association of Chartered Physiotherapists with an Interest in Neurology (ACPIN) and 360 doctors from the Association of British Neurologists (ABN) and the British Geriatrics Society (BSG).

Setting: Hospitals and rehabilitation centres in the UK.

Results: Replies were obtained from 84 occupational therapists (47%), 98 physiotherapists (55%) and 78 doctors (22%). Sixty-four occupational therapists (77%), 82 physiotherapists (84%) and 66 doctors (87%) indicated that they routinely performed somatosensory assessment as part of their clinical assessment. The two most commonly used measures were proprioception and light touch. Seventy-eight occupational therapists (93%), 88 physiotherapists (90%) and 67 doctors (91%) regarded sensory assessment as clinically significant in determining prognosis after stroke.

Conclusions: Despite published reservations concerning its usefulness and reliability, most therapists and doctors routinely assess somatosensory loss after stroke. All three professions agreed that somatosensory testing presented useful information for prognosis. Furthermore, all professional groups believe somatosensory assessment to be clinically relevant.

Are You Suggesting That's My Hand? The Relation Between Hypnotic Suggestibility and the Rubber Hand Illusion

Hypnotic suggestibility (HS) is the ability to respond automatically to suggestions and to experience alterations in perception and behavior. Hypnotically suggestible participants are also better able to focus and sustain their attention on an experimental stimulus. The present study explores the relation between HS and susceptibility to the rubber hand illusion (RHI). Based on previous research with visual illusions, it was predicted that higher HS would lead to a stronger RHI. Two behavioral output measures of the RHI, an implicit (proprioceptive drift) and an explicit (RHI questionnaire) measure, were correlated against HS scores. Hypnotic suggestibility correlated positively with the implicit RHI measure contributing to 30% of the variation. However, there was no relation between HS and the explicit RHI questionnaire measure, or with compliance control items. High hypnotic suggestibility may facilitate, via attentional mechanisms, the multisensory integration of visuoproprioceptive inputs that leads to greater perceptual mislocalization of a participant's hand. These results may provide insight into the multisensory brain mechanisms involved in our sense of embodiment.

A cognitive account of belief: a tentative road map

Over the past decades, delusions have become the subject of growing and productive research spanning clinical and cognitive neurosciences. Despite this, the nature of belief, which underpins the construct of delusions, has received little formal investigation. No account of delusions, however, would be complete without a cognitive level analysis of belief per se. One reason for this neglect is the assumption that, unlike more established and accessible modular psychological process (e.g., vision, audition, face-recognition, language-processing, and motor-control systems), beliefs comprise more distributed and therefore less accessible central cognitive processes. In this paper, we suggest some defining characteristics and functions of beliefs. Working back from cognitive accounts of delusions, we consider potential candidate cognitive processes that may be involved in normal belief formation. Finally, we advance a multistage account of the belief process that could provide the basis for a more comprehensive model of belief.

Using hypnosis to disrupt face processing: mirrored-self misidentification delusion and different visual media

Mirrored-self misidentification delusion is the belief that one's reflection in the mirror is not oneself. This experiment used hypnotic suggestion to impair normal face processing in healthy participants and recreate key aspects of the delusion in the laboratory. From a pool of 439 participants, 22 high hypnotisable participants ("highs") and 20 low hypnotisable participants were selected on the basis of their extreme scores on two separately administered measures of hypnotisability. These participants received a hypnotic induction and a suggestion for either impaired (i) self-face recognition or (ii) impaired recognition of all faces. Participants were tested on their ability to recognize themselves in a mirror and other visual media - including a photograph, live video, and handheld mirror - and their ability to recognize other people, including the experimenter and famous faces. Both suggestions produced impaired self-face recognition and recreated key aspects of the delusion in highs. However, only the suggestion for impaired other-face recognition disrupted recognition of other faces, albeit in a minority of highs. The findings confirm that hypnotic suggestion can disrupt face processing and recreate features of mirrored-self misidentification. The variability seen in participants' responses also corresponds to the heterogeneity seen in clinical patients. An important direction for future research will be to examine sources of this variability within both clinical patients and the hypnotic model.

Modelling psychiatric and cultural possession phenomena with suggestion and fMRI

Involuntary movements occur in a variety of neuropsychiatric disorders and culturally influenced dissociative states (e.g., delusions of alien control and attributions of spirit possession). However, the underlying brain processes are poorly understood. We combined suggestion and fMRI in 15 highly hypnotically susceptible volunteers to investigate changes in brain activity accompanying different experiences of loss of self-control of movement. Suggestions of external personal control and internal personal control over involuntary movements modelled delusions of control and spirit possession respectively. A suggestion of impersonal control by a malfunctioning machine modelled technical delusions of control, where involuntary movements are attributed to the influence of machines. We found that (i) brain activity and/or connectivity significantly varied with different experiences and attributions of loss of agency; (ii) compared to the impersonal control condition, both external and internal personal alien control were associated with increased connectivity between primary motor cortex (M1) and brain regions involved in attribution of mental states and representing the self in relation to others; (iii) compared to both personal alien control conditions, impersonal control of movement was associated with increased activity in brain regions involved in error detection and object imagery; (iv) there were no significant differences in brain activity, and minor differences in M1 connectivity, between the external and internal personal alien control conditions. Brain networks supporting error detection and object imagery, together with representation of self and others, are differentially recruited to support experiences of impersonal and personal control of involuntary movements. However, similar brain systems underpin attributions and experiences of external and internal alien control of movement. Loss of self-agency for movement can therefore accompany different kinds of experience of alien control supported by distinct brain mechanisms. These findings caution against generalization about single cognitive processes or brain systems underpinning different experiences of loss of self-control of movement.

Making an impact

Cognitive Neuropsychiatry has secured recognition in Thomson's Science and Social Science Citation Indices which will lead to the calculation of the journal impact factor.

Modulating the default mode network using hypnosis

Debate regarding the neural basis of the hypnotic state continues, but a recent hypothesis suggests that it may produce alterations in the default mode network (DMN). DMN describes a network of brain regions more active during low-demand compared to high-demand task conditions and has been linked to processes such as task-independent thinking, episodic memory, semantic processing, and self-awareness. However, the experiential and cognitive correlates of DMN remain difficult to investigate directly. Using hypnosis as a means of altering the resting ("default") state in conjunction with subjective measures and brain imaging, the authors found that the state of attentional absorption following a hypnotic induction was associated with reduced activity in DMN and increased activity in prefrontal attentional systems, under invariant conditions of passive visual stimulation. The findings that hypnosis and spontaneous conceptual thought at rest were subjectively and neurally distinctive are also relevant to understanding hypnosis itself.

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.

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.

Somatosensory recovery: A longitudinal study of the first 6 months after unilateral stroke

PURPOSE

The aim of this study was to characterize the recovery pattern of stroke patients in the first 6 months following stroke.

METHOD

Using the Rivermead Assessment of Somatosensory Performance (RASP), the Motricity index and the Barthel Activities of Daily Living (ADL) index, a case series of serial somatosensory and motor measurements was made on 18 patients with a diagnosis of a first ever stroke. Patients comprised 2 distinct groups, acute and subacute. The acute group were seen weekly for the first month post onset and the subacute group were seen monthly for 6 months. Participants were seen at hospital, regional rehabilitation unit and/or the participant's home. Standard local rehabilitation was given.

RESULTS

The somatosensory subtest of proprioception demonstrated the greatest level of recovery. No patient achieved full recovery on all somatosensory subtests. Motor and functional recovery demonstrated continual improvement over time, somatosensory recovery showed marked variation in subtests both within and between patients.

CONCLUSION

Of the 18 patients tested there were no consistent, generalizable, recognizable patterns of sensory recovery demonstrated.

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.

Influence of age and sex on line bisection: a study of normal performance with implications for visuospatial neglect

Line bisection is an established clinical task used to diagnose visuospatial neglect. To date, few studies have considered the extent to which age and sex as background variables contribute to bisection performance. Both variables affect the neural substrates underlying cognitive processes and hence the behavioural performance of bisection. The purpose of this study was to examine the effects of age and sex on normal bisection performance, using three different line lengths to elucidate the influence of these potential contributing factors. Seventy men and 70 women, divided equally into seven age-cohorts between 14 and 80 years, bisected lines. Results indicated clear age- and sex-related differences both in the magnitude and direction of bisection deviations across the three line lengths. Differences are discussed in terms of neural changes across the adult lifespan including hemispheric differences and hormonally mediated changes.

Residual haptic sensation following stroke using ipsilateral stimulation

In 1987, Weiskrantz and Zhang described a stroke patient with severe somatosensory loss who, nevertheless, demonstrated impressive residual sensory performance when required to touch the affected limb with her ipsilesional hand (self touch; ST). The current study set out to ascertain the prevalence and characteristics of self-touch enhancement (STE) in patients with unilateral stroke and hemihypaesthesia. Thirty-nine stroke patients who were referred with hemihypaesthesia fulfilled the criteria. STE was defined where a patient showed a statistically significant increase (p<0.05) in performance for (i) detection, (ii) localisation and/or (iii) perceived intensity during touch with their ipsilesional hand, compared with standard experimenter elicited sensory performance. Group comparisons between the conventional touch versus ST conditions revealed significant differences for detection (p<0.01), intensity estimation (p<0.01) and localisation (p<0.001) using ST. Twenty-two of the 39 patients (56.4%) showed STE on at least one assessment mode. In detection, 16 (41%) patients showed STE; for localisation, 12 patients (31%) showed STE and for intensity, 17 patients (44%) showed STE. Out of the 22 patients with STE, 17 had right hemisphere lesions. In summary, more than half of the stroke patients showed reliable and significant improvements in somatosensory performance when using their unaffected hand as the source of tactile stimulation. This striking phenomenon suggests that the threshold for the impaired hand is affected by active involvement of the contralateral (ipsilesional) limb when delivering the stimulus contact. Possible mechanisms to explain these findings are discussed.

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.

Illness related deception: social or psychiatric problem?

In this paper we question the validity of factitious disorder as a meaningful psychiatric diagnosis. When the diagnosis is used there is often the assumption that the person engaging in the 'deception' is not lying in the traditional sense of being deliberately misleading. Moreover, little is known about the aetiology or psychopathology underlying factitious disorder, and the legitimacy of deception as a mental disorder has been questioned. It is argued that while illness deception may be more common that hitherto assumed, factitious disorder as a distinct type of psychiatric disorder is conceptually flawed, diagnostically impractical and clinically unhelpful and should be dropped from existing nosologies.

Hereditary Prosopagnosia: the First Case Series

Prosopagnosia is defined as a specific type of visual agnosia characterised by a discernible impairment in the capacity to recognise familiar people by their faces. We present seven family pedigrees with 38 cases in two to four generations of suspected hereditary prosopagnosia, detected using a screening questionnaire. Men and women are impaired and the anomaly is regularly transmitted from generation to generation in all pedigrees studied. Segregation is best explained by a simple autosomal dominant mode of inheritance, suggesting that loss of human face recognition can occur by the mutation of a single gene. Eight of the 38 affected persons were tested on the Warrington Recognition Memory Test for Faces (RMF; Warrington, 1984), famous and family faces tests, learning tests for internal and external facial features and a measure of mental imagery for face and non-face images. As a group, the eight participants scored significantly below an age- and education-matched comparison group on the most relevant test of face recognition; and all were impaired on at least one of the tests. The results provide compelling evidence for significant genetic contribution to face recognition skills and contribute to the promise offered by the emerging field of cognitive neurogenetics.

Hypnotic depth and response to suggestion under standardized conditions and during FMRI scanning

Hypnosis is a potentially valuable cognitive tool for neuroimaging studies. However, understandable concern that Magnetic Resonance Imaging (MRI) in particular may adversely affect hypnotic procedures remains. Measurements of hypnotic depth and responsiveness to suggestions were taken using a standardized procedure that met all the requirements for functional MRI (fMRI). Testing outside the scanning environment showed reliable and stable changes in subjective hypnotic depth, with no carryover once the hypnosis had been terminated. Within-subject comparisons showed that the magnitude and pattern of these changes and the degree of responsiveness to hypnotic suggestion were not discernibly affected by the fMRI environment. It is concluded that hypnosis can be employed as a discrete and reliable cognitive tool within fMRI neuroimaging settings.

Diagnosing delusions: a review of inter-rater reliability

Although several studies have examined the reliability of diagnosing delusions there is no comprehensive review of the literature. Therefore, the reliability of diagnosing 'delusions in general' and the subcategory of 'bizarre delusions' was reviewed, including both structured interview and standardized instrument methods. The literature suggests that delusions in general can be diagnosed reliably with both structured interview and standardized instruments. However, bizarre delusions are not reliably diagnosed by either, suggesting that this concept may have little clinical validity. Nevertheless, many of the studies reviewed are poorly designed or subject to significant confounds. Criteria are suggested for adequate future studies.

Awareness and knowing: Implications for rehabilitation

It has been known for well over a century that brain-damaged patients are often unaware of the very deficits that impair performance in everyday life. Pathologies of awareness have been described for many neurological, psychiatric and neuropsychological deficits and the construct of "awareness" or "insight" understandably now receives attention from many researchers within the clinical and cognitive neurosciences. This paper does not attempt to explain the nature of consciousness or its impairment but rather considers four aspects of consciousness/awareness that health care professionals interested in understanding, measuring and improving deficits of awareness should consider.

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.

The Cardiff Anomalous Perceptions Scale (CAPS): a new validated measure of anomalous perceptual experience

The study describes the Cardiff Anomalous Perceptions Scale (CAPS), a new validated measure of perceptual anomalies. The 32-item CAPS measure is a reliable, self-report scale, which uses neutral language, demonstrates high content validity, and includes subscales that measure distress, intrusiveness, and frequency of anomalous experience. The CAPS was completed by a general population sample of 336 participants and 20 psychotic inpatients. Approximately 11% of the general population sample scored above the mean of the psychotic patient sample, although, as a group, psychotic inpatients scored significantly more than the general population on all CAPS subscales. A principal components analysis of the general population data revealed 3 components: "clinical psychosis" (largely Schneiderian first-rank symptoms), "temporal lobe disturbance" (largely related to temporal lobe epilepsy and related seizure-like disturbances) and "chemosensation" (largely olfactory and gustatory experiences), suggesting that there are multiple contributory factors underlying anomalous perceptual experience and the "psychosis continuum."