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PubMed1996

The development of in vivo tracer methods to obtain new information about human disease: a study of the hallucinating brain.

An outline is provided of the development of methodological strategies to address the question of focal cerebral activation during hallucinations in schizophrenic patients. In so doing, the innovation and diligence required to tailor in vivo tracer procedures to specific clinical research issues are highlighted. Attention is drawn to the complexity of methodological advances and the way in which they are based upon close scientific and technical collaboration between clinical scientists, and non-clinical scientists and research support staff.

Hallucinations↗
PubMed1994

Release hallucinations and tiapride.

The authors describe seven patients in whom the administration of tiapride led to the disappearance of visual hallucinatory manifestations with the characteristics of "release hallucinations", the results being maintained throughout the period of treatment. The authors also discuss the mechanism and presumed site of action of the drug.

AIDS-Related Opportunistic Infections↗
PubMed1997

A study of visual hallucinations in patients with Parkinson's disease.

In a hospital-based case-control study 29 patients with idiopathic Parkinson's disease (PD) and visual hallucinations (VH) were compared with 58 PD patients matched for age and disease duration, but without VH. VH patients had more frequently sleep disturbances and dementia, higher PD-related disability (Schwab-England scale), and took selegiline more frequently as an anti-Parkinsonian drug. The patient groups did not differ in age at PD onset, Webster score, treatment duration, dosage of any anti-Parkinsonian drug, frequency of levodopa-associated movement disorders, or measures on brain CT. After a median follow-up period of 27 months more VH patients had developed wearing-off and freezing phenomena, while their scores in the Mini Mental State Examination were lower. Nursing home placement during the follow-up period was associated with higher PD-related disability in VH patients.

Aged↗
PubMed1988

Platelet MAO activity in hallucinating and paranoid schizophrenics: a review and meta-analysis.

Published studies of platelet monoamine oxidase (MAO) activity of paranoid (P) and nonparanoid (NP) schizophrenics and normal controls, and of hallucinating (H) and nonhallucinating (NH) schizophrenics and normal controls were critically reviewed, and summary analyses were conducted on the original published data. Methods of comparing results across studies are discussed. Meta-analysis of the results of 11 analyses from 9 studies, examining a total of 165 P and 152 NP schizophrenics and 985 normal controls, indicated that the typical P schizophrenic studied had platelet MAO activity lower than that of 61% of NP schizophrenics and 79% of normal controls. Meta-analysis of the results of 8 separate analyses from 6 studies comprising 130 H, 81 NH schizophrenics, and 186 normal controls indicated that the average H schizophrenic studied had platelet MAO activity lower than that of 84% of NH schizophrenics and 80% of normal controls. In comparison with normal control values, P schizophrenics had the greatest mean percentage decrease in platelet MAO activity (30%), followed by NP schizophrenics (24%), and H schizophrenics (24%). These findings could not readily be attributed to diagnostic, demographic, or methodological factors, nor to the effects of alcohol or neuroleptics.

Blood Platelets↗
PubMed1980

Agitation, disorientation, and hallucinations in patients on cimetidine: a report of three cases and literature review.

Cimetidine, the first of a new class of pharmacologic agents that dramatically inhibit basal gastric acid secretion, is achieving widespread use for the treatment of such acid peptic disorders as duodenal ulcers, gastritis, and reflux esophagitis. Three patients are presented who experienced agitation, disorientation, and hallucinations while being treated with cimetidine. A review of the literature revealed that central nervous system side effects of cimetidine can occur within 24 hours of treatment with the drug; are often unrecognized or misdiagnosed by clinicians, and are reversed within 12 to 48 hours after the discontinuation of the medication.

Adult↗
PubMedDate not supplied

Auditory event-related potential (ERP) and difference-wave topography in schizophrenic patients with/without active hallucinations and delusions: a comparison with young obsessive-compulsive disorder (OCD) and healthy subjects.

Event-related potentials (ERPS) in schizophrenics have been reported to show a reduced P3 on the left and less frontal mismatch negativity (MMN). But the specificity of such findings to component, its locus, the type of eliciting event and patient group remains uncertain. Hence, we examined ERP topography for P3, N2 and 3 precursor peaks according to stimulus (3-tone oddball), attention condition (diffuse/focused) and four types of difference-waves. We contrasted 24 healthy and 13 OCD subjects with schizophrenic patients with high versus low ratings of active delusions and hallucinations (12 paranoid-hallucinatory, PH; 12 nonparanoid, NP). P3 peaks were delayed and reduced in NP and PH groups. Midline peaks were usual in focused attention and a right bias in diffuse attention. P3 responses to irrelevant standards remained lateral in NP and small in OCD patients. All showed a small left and anterior bias in the P3-like peak in difference-waves. Mismatch negativity waveform (MMN) peaks shifted to the right in OCD, to both sides in PH and posteriorly in NP patients. Frontal processing negativity was biased to the left (early) in NP and to the right (late) in PH groups. Early peak topography reflected some later changes (e.g. PH and NP groups; P1-like peak, right bias absent; N1-like peak depressed and widely distributed; NP group, P2-like peak smaller on the left). In OCD patients, peak latencies were topographically undifferentiated (P1, P2) or delayed (N2). The OCD group showed an unusual regional allocation of processing effort. Before 200 ms frontocentral activity was more widespread in Ph and NP groups. Lateralization of negativity in target- and nontarget-derived difference-waves may reflect differential disruption of the frontal-temporal dialogue in registering important vs unimportant features. NP patients, in particular, treated irrelevant stimuli anomalously.

Adolescent↗
PubMed1988

Increased geomagnetic activity and the occurrence of bereavement hallucinations: evidence for melatonin-mediated microseizuring in the temporal lobe?

This study was designed to test the hypothesis that common bereavement apparitions are hallucinatory experiences evoked by transient electrical instability within the (glucocorticoid) sensitized mesiobasal temporal lobes. All first hand reports of 'postmortem apparition' experiences were collected from a published data base. The days on which the experiences occurred displayed significantly greater (mean increase = 10 gamma) geomagnetic activity compared to the days before or afterwards. These results suggest that bereavement apparitions are situation-specific hallucinations evoked by microseizures within sensitized temporal lobe structures; the occurrence of these microseizures might be facilitated by suppression in melatonin levels that could accompany sudden increases in geomagnetic activity.

Bereavement↗
PubMed1995

Schizophrenic auditory hallucinations are associated with increased regional cerebral blood flow during verbal memory activation in a study using single photon emission computed tomography.

Single photon emission tomography with split-dose technetium-99m-d, l-hexamethyl-propylene amine oxime was used to measure regional cerebral blood flow (rCBF) during a memory-activation paradigm in a group of 18 medicated DSM-III-R schizophrenic patients. The relationship between clinical features of schizophrenia and rCBF patterns was examined. Increased blood flow to the left basal ganglia was revealed during activation in patients reporting hallucinations in the previous month, a finding that was not influenced by medication dose or other confounding variables. This result adds to previous functional imaging studies that have related basal ganglia abnormalities to hallucinatory phenomena and suggests that left basal ganglia hyperactivity may be relevant to an internal monitoring deficit responsible for the appearance of those symptoms in schizophrenia.

Adult↗
PubMed1994

Hallucinations following cardiac surgery in a paediatric intensive care unit.

Abnormal behaviour as a result of benzodiezapine withdrawal has been reported in children in intensive care. Other causes of abnormal behaviour may be as a result of intensive care unit (ICU) psychosis or delirium. ICU psychosis in adults is well documented but is rarely reported in children, hence this report on a child who suffered hallucinations after cardiac surgery, and discussion on possible causes and the need for greater awareness of this possible complication.

Cardiac Surgical Procedures↗
PubMed2006

Self-care symptom management strategies for auditory hallucinations among patients with schizophrenia in Taiwan.

This descriptive study explored self-care management strategies for controlling auditory hallucinations (AH) among Taiwanese patients with schizophrenia. Patients with schizophrenia (N = 200) were recruited by convenience from 2 general hospitals. Self-report and semistructured questionnaires were used to identify 41 self-management strategies. Strategies were categorized into 3 groups: physiological, cognitive, and behavioral. Ignoring AH, a cognitive strategy, was the single most frequently used strategy. As a group, strategies in the behavioral category were used the most. The most common resource for strategies was self-learning. These results can help health care providers better understand self-care management strategies for coping with AH among outpatients with schizophrenia. We suggest the development of a manual of selected self-care strategies identified by these patients to empower other patients to use self-care for AH.

Adaptation, Psychological↗
PubMed2005

Self-care symptom management strategies for auditory hallucinations among inpatients with schizophrenia at a Veterans' Hospital in Taiwan.

The purpose of this study was to explore self-care management strategies for auditory hallucinations (AHs) among inpatients with schizophrenia. Self-report and semistructured questionnaires were used to identify 36 self-management strategies of 200 inpatients with schizophrenia living at a veterans' hospital in Taiwan. The most commonly used management category was behavioral change and the most commonly used strategy was ignoring the AHs. The most common resource for strategies was self-learning. These results can help broaden health care providers' understanding about self-care management strategies for coping with AHs among inpatients with schizophrenia. Developing a manual containing selected self-care strategies and incorporating those strategies into cognitive-behavioral psychotherapy could be useful and beneficial to patients experiencing AHs.

Adaptation, Psychological↗
PubMed2005

Slow transcranial magnetic stimulation can rapidly reduce resistant auditory hallucinations in schizophrenia.

BACKGROUND: Almost a quarter of patients with schizophrenia present with resistant auditory verbal hallucinations (AVH), a phenomenon that may relate to activation of brain areas underlying speech perception. Repetitive transcranial magnetic stimulation (rTMS) at 1 Hz reduces cortical activation, and recent results have shown that 1-Hz left temporoparietal rTMS may reduce AVH. The aim of this study was to replicate recent data and investigate whether low-frequency rTMS with a high total stimulation number delivered in a shorter 5-day block produces similar benefit. METHODS: Ten right-handed schizophrenia patients with resistant AVH received 5 days of active rTMS and 5 days of sham rTMS (2,000 stimulations per day at 90% of motor threshold) over the left temporoparietal cortex in a double-blind crossover design. The two weeks of stimulation were separated by a 1-week washout period. RESULTS: AVH were robustly improved (56%) by 5 days active rTMS, whereas no variation was observed after sham. Seven patients were responders to active treatment, five of whom maintained improvement for at least 2 months. CONCLUSIONS: These data confirm the efficiency of low-frequency rTMS applied to the left temporoparietal cortex, compared with sham stimulation, in reducing resistant AVH. This improvement can be obtained in only 5 days without serious initial adverse events.

Adult↗
PubMedDate not supplied

The occipital white matter lesions in Alzheimer's disease patients with visual hallucinations.

PURPOSE: Investigators have suggested that lesions responsible for visual hallucinations (VHs) are situated in the visual association cortex. The aim of this study was to assess the relationship between occipital white matter lesions and VHs in Alzheimer's disease (AD) patients. METHODS: AD patients with a history of VHs (AD+VH) and those without (AD-VH) were retrospectively studied. The two groups of patients were matched by sex and mental state. All subjects underwent brain magnetic resonance image (MRI) scans. The periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWHs) on MRIs were rated by two raters using a semiquantitative scoring method (0=absent; 6=confluent). RESULTS: Five AD+VH patients and five AD-VH patients were enrolled into this study. The occipital PVH score was higher in the AD+VH patients than in the AD-VH patients. The occipital DWH score was zero in both groups. CONCLUSION: The presence of VHs in AD was associated with increased occipital PVHs and an absence of occipital DWHs on brain MRIs, implying that structural lesions in the geniculocalcarine region and preserved subcortical connections with visual association areas are involved in the genesis of VHs in AD.

Aged↗
PubMed2006

Thought as action: inner speech, self-monitoring, and auditory verbal hallucinations.

Passivity experiences in schizophrenia are thought to be due to a failure in a neurocognitive action self-monitoring system (NASS). Drawing on the assumption that inner speech is a form of action, a recent model of auditory verbal hallucinations (AVHs) has proposed that AVHs can be explained by a failure in the NASS. In this article, we offer an alternative application of the NASS to AVHs, with separate mechanisms creating the emotion of self-as-agent and other-as-agent. We defend the assumption that inner speech can be considered as a form of action, and show how a number of previous criticisms of applying the NASS to AVHs can be refuted. This is achieved in part through taking a Vygotskian developmental perspective on inner speech. It is suggested that more research into the nature and development of inner speech is needed to further our understanding of AVHs.

Ego↗
PubMed2004

Acting on command hallucinations and dangerous behavior: a critique of the major findings in the last decade.

Command hallucinations (CH) have recently become the focus of research into positive symptoms of schizophrenia. The importance of CH has become clear for theoretical and practical reasons, because CH are regarded as potentially the most dangerous symptoms of schizophrenia. The aim is to critically review research that has attempted to better understand CH and develop theories that may predict behavior and shape psychological treatments. This review draws together, presents, and critically discusses the current disparate body of literature produced (1990-2000) considering compliance with CH. The literature can be grouped broadly into three overlapping classes. (1) Studies testing for a relationship between CH and compliance. (2) Studies considering factors associated with acting on CH (mediating variables). (3) Studies that look for a relationship between CH and dangerous behavior. The body of literature is in its infancy and marred by methodological difficulties. Researchers have asked differing questions about different samples while hoping to provide similar answers. While acknowledging difficulties in interpreting the literature, themes do emerge. The weight of the evidence is that some individuals who hear commands will act on them. However, some studies show no link or only a weak link and although methodological errors account for some of the inconsistent results, there are also clearly individual differences. The relationship between command and action is more complex than many researchers have assumed. One conjecture is that the relationship is established via psychological processes or mediating variables which include beliefs about the voice and content of instruction. Prediction of compliance with commands is of further interest when dangerous behavior results. It is postulated that the issue of dangerousness is subject to the same mediating variables as other commands. It is clear however, that CH are not sufficient to produce action in isolation and that psychological processes mediate the process.

Acting Out↗
PubMed2006

Neural correlates of inner speech and auditory verbal hallucinations: a critical review and theoretical integration.

The neuroimaging and neurophysiological literature on inner speech in healthy participants and those who experience auditory verbal hallucinations (AVHs) is reviewed. AVH-hearers in remission and controls do not differ neurologically on tasks involving low levels of verbal self-monitoring (VSM), such as reciting sentences in inner speech. In contrast, on tasks involving high levels of VSM, such as auditory verbal imagery, AVH-hearers in remission show less activation in areas including the middle and superior temporal gyri. This pattern of findings leads to a conundrum, given that mentation involving low levels of VSM is typically held to form the raw material for AVHs. We address this by noting that existing neuroimaging and neurophysiological studies have been based on unexamined assumptions about the form and developmental significance of inner speech. We set out a Vygotskian approach to AVHs which can account for why they are generally experienced as the voice of another person, with specific acoustic properties, and a tendency to take the form of commands. On this approach, which we argue is consistent with the neural correlates evidence, AVHs result from abnormalities in the transition between condensed and expanded dialogic inner speech. Further potential empirical tests of this model are discussed.

Attention↗
PubMed2005

The neural basis of hallucinations and delusions.

Schizophrenia is a biologically based disorder characterised by false perceptions (hallucinations) and false beliefs (delusions). The underlying physiological cause of these mental abnormalities remains unknown. There is increasing evidence that one class of symptom, the 'made experiences' including delusions of alien control and thought insertion, is associated with abnormalities in the mechanism that predicts the outcome of intended actions (the forward model). For these patients active movements feel like passive movements. As a result these patients do not feel in control of their actions. However, comparison with various neurological disorders, such as those associated with parietal lobe lesions, suggest that this abnormal experience is not sufficient to explain the feeling that some other agent is controlling is one's actions. Preliminary evidence suggests that patients with schizophrenia have an exaggerated sense of agency. In combination with the feeling of not being in control, this exaggerated sense of agency could explain delusions of alien control in which the patient attributes his own actions to another agent. Little is yet know about the neural basis of the predictive mechanisms that create the feeling that we are in control of our movements. Such prediction requires integration of information about intended movements generated in frontal cortex with sensory processing in posterior regions of the brain. Measures of functional connectivity suggest that long-range interactions between frontal and posterior regions are abnormally reduced in patients with schizophrenia. Further research is needed to explore the precise involvement of long-range connections in the mechanisms of forward modelling.

Animals↗
PubMed2005

Rating the severity and character of transient cocaine-induced delusions and hallucinations with a new instrument, the Scale for Assessment of Positive Symptoms for Cocaine-Induced Psychosis (SAPS-CIP).

BACKGROUND: Cocaine can induce transient psychotic symptoms. We examined the phenomenology of such cocaine-induced psychosis (CIP) using a modified version of the Scale for Assessment of Positive Symptoms (SAPS), a well-validated instrument for the assessment of schizophrenic psychosis. METHODS: We developed a new instrument, the Scale for Assessment of Positive Symptoms for Cocaine-Induced Psychosis (SAPS-CIP), based on the well-validated SAPS. We interviewed 243 unrelated cocaine-dependent adults using both the SAPS-CIP and an instrument for the identification of cocaine-induced paranoia, the Cocaine Experience Questionnaire (CEQ). RESULTS: One hundred and eighty-one (75%) of the subjects endorsed CIP using the CEQ. With the SAPS-CIP, hallucination (HAL) and delusion (DEL) scores correlated strongly, and the DEL domain showed excellent concurrent validity with the CEQ. We observed significant positive correlations, respectively, between severity of HAL and DEL, and lifetime number of episodes of cocaine use, and negative correlations with age at onset of cocaine use. CONCLUSIONS: The results suggest that CIP consists of transient delusional and hallucinatory symptoms, which tend to occur together and co-vary in severity. It appears that rating cocaine-induced paranoia alone (e.g., with the CEQ) can identify most subjects experiencing CIP. However, the SAPS-CIP is useful for quantifying the severity of CIP according to operational criteria. Our data provide additional evidence that CIP is a sensitizing response.

Adult↗