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PubMed1999

A controlled study of temporal lobe structure volumes and P300 responses in schizophrenic patients with persistent auditory hallucinations.

Recent studies of cerebral pathology in patients with schizophrenia have focused on symptomatological and electrophysiological correlates of reduced temporal lobe structure volumes. Volume deficits of the left superior temporal gyrus have been correlated with auditory hallucinations as well as to left-sided P300 amplitude reduction. However, caution is needed to interpret correlational data as evidence of a specific relationship. Therefore, a controlled study was undertaken on schizophrenic patients with and without auditory hallucinations. MRI-defined volumes of the left superior temporal gyrus and other temporal lobe structures were quantified from 3-mm coronal slices in 15 schizophrenic patients with chronic auditory hallucinations (hallucinators), 15 schizophrenic patients without auditory hallucinations (nonhallucinators) and 17 healthy controls. In all subjects a simple oddball paradigm was used to elicit P300 responses at temporal and centro-parietal electrode sites. No evidence was found for volume reductions of temporal lobe structures in the combined patient group compared with controls, or in the hallucinators compared with the nonhallucinators. The patients did show left P300 amplitude reduction compared with controls, particularly in the hallucinator group. Correlations between volumes of left temporal lobe structures and left P300 amplitudes were low and not significant. The results of the present study do not indicate that auditory hallucinations and associated abnormal electrophysiological activity are the consequence of atrophy of localized temporal lobe structures. However, replication in a larger sample of subjects is needed before firm conclusions can be drawn.

Adult↗
PubMed2003

Role of coping strategies and attitudes in mediating distress due to hallucinations in schizophrenia.

The purpose of the present study was to determine the role of coping strategies and attitudes in predicting distress due to hallucinations in schizophrenia. Seventy-five chronic stable schizophrenia patients were assessed with respect to sociodemographic profile, clinical variables, general psychopathology, phenomenology (severity) of hallucinations, attitude towards hallucinations, distress due to hallucinations (determined by two measures) and coping strategies used to deal with hallucinations. On multiple stepwise regression analysis, 'severity of hallucinations' and 'problem-solving coping strategies' contributed significantly to both measures of distress. It can be concluded that distress due to hallucinations in schizophrenia is determined by severity of hallucinations (stressor) and problem-solving coping strategies. Attitudes do not seem to play any role in this respect.

Adaptation, Psychological↗
PubMed1996

Properties of complex hallucinations associated with deficits in vision.

Complex visual hallucinations are known to occur in individuals with impaired vision yet whose emotional and intellectual functions are within the normal range. These hallucinations, which were first reported by Charles Bonnet in 1760, have been described in many case studies, but have not been analyzed empirically to determine their major properties. In the present study, sixty complex hallucinators labeled as Charles Bonnet hallucinators were administered a questionnaire to determine the properties of their hallucinations. Combined use of multiple-correspondence analysis and hierarchical cluster analysis reveals a set of features that characterize the 'typical' Charles Bonnet hallucinatory experience: the hallucinators' experience occurs while they are alert and with the eyelids open; a sharply focused image appears suddenly, without any apparent trigger or voluntary control; the hallucination is present for seconds, does not move during this time, then suddenly vanishes. These features are discussed in terms of a 'dimension' of hallucinatory/perceptual experience, which ranges from discrete perceptual experiences to multiple, changing experiences. Possible mechanisms that underlie the Charles Bonnet hallucinations are discussed.

Blindness↗
PubMed2006

Auditory hallucinations in schizophrenia: intrusive thoughts and forgotten memories.

INTRODUCTION: This paper presents a new cognitive model of auditory hallucinations in schizophrenia. We suggest that auditory hallucinations are auditory representations derived from the unintentional activation of memories and other irrelevant current mental associations. Our model proposes that a combination of deficits in intentional inhibition and contextual memory is critical to the experience of auditory hallucinations. The failure in intentional inhibition produces unwanted and uncontrollable mental events which are not recognised because they have lost the contextual cues that would normally facilitate recognition. METHODS: This article amalgamates recently published data and presents a reanalysis of the findings on 43 patients with a diagnosis of schizophrenia (Badcock, Waters, Maybery, & Michie, 2005; Waters, Badcock, Maybery, & Michie, 2003a; Waters, Maybery, Badcock, & Michie, 2004a). Relative risk was also estimated to determine whether the combination of deficits increases the risk of having auditory hallucinations. RESULTS: Almost 90% of patients currently experiencing auditory hallucinations showed the predicted combination of deficits on both inhibition and context memory, compared to only a third of patients without hallucinations. In addition, the results showed that those patients with the specified cognitive deficits were at an especially increased risk of having auditory hallucinations relative to patients without the deficits. CONCLUSIONS: The results of our investigations strongly support the role of intentional inhibition and context memory in auditory hallucinations. Critical consideration of the findings also suggests that additional cognitive processes might be important for the expression of this symptom.

Cognition↗
PubMed2002

Tc-99m ethylcysteinate dimer brain SPECT perfusion imaging in ictal nonepileptic visual hallucinations.

PURPOSE: Visual hallucinations can occur within the central nervous system and may be associated with a lesion anywhere in the visual pathway. The purpose of this study was to assess "ictal" regional cerebral blood flow with Tc-99m ethylcysteinate dimer (ECD) SPECT in patients having acute hallucinations, and to compare the findings to the "interictal" state. METHODS: A prospective study was performed to evaluate patients admitted to the neurology department with nonpsychiatric and nonepileptic visual hallucinations. The nine patients included in the study underwent thorough neurologic and psychiatric evaluations. A computed tomographic (CT) scan was performed when each patient was admitted, and electroencephalographic (EEG) recordings were made during their hallucinations. All patients underwent a brain SPECT while having acute hallucinations (ictal SPECT), and a follow-up scan was obtained 2 to 3 weeks later. RESULTS: All patients had normal ictal EEG findings during the hallucinations. Seven of nine patients had increased perfusion on the SPECT studies in one or more regions, with a mean lesion-to-contralateral ratio of 2.1 (range, 1.5 to 2.7). Three of the seven patients had findings consistent with a cerebrovascular accident. After treatment, the hallucinations disappeared in two patients and the motor deficit improved dramatically. The follow-up SPECT study showed significant improvement in all patients 1 week later. Charles Bonnet syndrome, frontal lobe dementia, and Anton syndrome were diagnosed in three other patients, and the last one had no identifiable background disease, all with normal findings of EEG, CT, and magnetic resonance examinations. They all responded readily to carbamazepine therapy, and the follow-up SPECT study showed resolution of the findings. Two of nine patients showed posterior cortical hypoperfusion, and eventually Lewy body disease was diagnosed. The SPECT showed no evidence of regional hyperperfusion. CONCLUSIONS: This prospective preliminary study suggests that brain imaging using SPECT may be useful in identifying the mechanisms and evolution of blood flow abnormalities in certain subgroups of patients who have visual hallucinations and may assist in the selection of specific therapy.

Aged↗
PubMed1994

Visual hallucinations in patients from an ophthalmology clinic and medical clinic population.

Although visual hallucinations have been associated with patients with visual disorders, no study has specifically examined whether visual hallucinations are indeed more prevalent than in a general medical population. In this study, 127 consecutive visual disorder patients and 100 consecutive general medical patients were screened for complex visual hallucinations. A total of 6.3% of visual disorder patients and 2% of general medical patients had visual hallucinations. Interestingly, the two medical patients with visual hallucinations also had visual disorders. Factors significantly associated with visual hallucinations were female sex (p = .029) and lower cognitive score (p = .001). Data from a previous study of patients with the visual disorder age-related macular degeneration were combined with this study to increase the sample size of visual hallucinators. Factors significantly associated with visual hallucinations in the combined sample were female sex (p = .015), living alone (p = .019), having hearing problems (p = .047), older age (p = .013), and lower cognitive score (p < .001). Implications and future research are discussed.

Adolescent↗
PubMed2000

Association study of dopamine receptor gene polymorphisms with drug-induced hallucinations in patients with idiopathic Parkinson's disease.

Some patients with idiopathic Parkinson's disease experience hallucinations as a result of treatment with levodopa and dopamine agonists. There is evidence for some heterogeneity in these hallucinating patients based on duration of Parkinson's disease at onset of hallucinations. We compared the frequency of polymorphisms in the dopamine D2 and D3 receptor genes between patients with drug-induced hallucinations and non-hallucinating patients. Two polymorphisms close to DRD2 and one in DRD3 were studied. No association was found with the whole group of hallucinating patients and their controls. However, an association was found with late-onset hallucinations and the C allele of the TaqIA polymorphism, 10.5 kb 3' to DRD2. This polymorphism may be in linkage disequilibrium with a mutation in DRD2 or a nearby gene that predisposes to drug-induced hallucinations which occur later in the course of idiopathic Parkinson's disease.

Alleles↗
PubMed2006

Features associated with the development of hallucinations in Parkinson's disease.

OBJECTIVE: To identify features related to the development of hallucinations in Parkinson's disease (PD). MATERIALS AND METHODS: Seventy PD patients with hallucinations (group 1) and 60 PD patients without hallucinations (group 2) were evaluated for disease severity, presence of motor complications, rapid eye movement (REM) behavior disorder (RBD), and antiparkinsonian drug profile. The ages at the emergence of hallucinations and duration of disease in group 1 were matched with the ages at the last visit of those in group 2. RESULTS: Disease severity and presence of motor complications were similar in both groups. RBD was more frequently encountered among hallucinators than among non-hallucinators (P = 0.007). The mean duration and daily doses of levodopa and other dopaminergic drugs did not differ in both groups; however, the usage of anticholinergics and amantadine were significantly more frequent in group 2, unexpectedly. CONCLUSIONS: The presence of RBD was significantly more common in hallucinators; however, severity of PD, duration and daily doses of dopaminergic drugs were not associated with the emergence of hallucinations.

Adult↗
PubMed1982

The psychopathology of hallucinations--a methodological analysis.

A psychiatry based on operational and dynamic principles requires a new definition of hallucinations which is both heuristically useful and helpful for the understanding of the phenomenon of hallucinations. The time-hallowed definition of hallucinations as 'perceptions without stimulation of the sense organs' is both incorrect and a relic of late 19th century para-physiological thinking. Heuristically it leads into a blind alley. Central to the redefinition of hallucinations is the conception of the hallucinator, the author of his hallucinations, homologous to the dreamer, the author of his dreams. This idea was held firmly by early French 19th century clinicians, who were inspired by a holistic and operational conception in philosophy. Hallucinations are a multifaceted complex human mental activity and defined by means of a number of parameters held together as an indivisible whole. Hallucinations are described phenomenologically, psychologically, dynamically, psychodynamically, emotionally, logically, nosologically, and interpersonally.

Dreams↗
PubMed2001

Modality specific neural correlates of auditory and somatic hallucinations.

Somatic hallucinations occur in schizophrenia and other psychotic disorders, although auditory hallucinations are more common. Although the neural correlates of auditory hallucinations have been described in several neuroimaging studies, little is known of the pathophysiology of somatic hallucinations. Functional magnetic resonance imaging (fMRI) was used to compare the distribution of brain activity during somatic and auditory verbal hallucinations, occurring at different times in a 36 year old man with schizophrenia. Somatic hallucinations were associated with activation in the primary somatosensory and posterior parietal cortex, areas that normally mediate tactile perception. Auditory hallucinations were associated with activation in the middle and superior temporal cortex, areas involved in processing external speech. Hallucinations in a given modality seem to involve areas that normally process sensory information in that modality.

Adult↗
PubMed2006

Persistent auditory hallucinations.

BACKGROUND: There is still a significant proportion of psychotic patients who suffer from persistent auditory hallucinations (PAH) in spite of treatment. The objective of our study was to analyze those clinical dimensions that characterize persistent hallucinators in comparison with episodic hallucinators. SAMPLING AND METHODS: Ninety-one outpatients with AH were assessed through semistructured interviews. The interviews included the Psychotic Symptom Rating Scales for AH and the Krawiecka scale. They elicited descriptions about the persistence of AH, existence of pleasurable hallucinations and other types of hallucinations. RESULTS: Forty-five patients fulfilled criteria for reported PAH. Persistent hallucinators showed greater scores in frequency and duration of hallucinations, Krawiecka total score and incoherence of speech. Moreover, pleasurable experiences were more frequent in this group of patients. Logistic regression analysis rendered a model with the following variables: duration of voices, degree of control and pleasurable hallucinations. CONCLUSION: Specific dimensions of AH can predict the possibility of treatment resistance.

Adult↗
PubMed1997

Visual hallucinations in the elderly.

Visual hallucinations, without auditory hallucinations and in the elderly, are not usually based on previous psychiatric illness. The elderly can, of course, hallucinate as part of severe depression or a life-long schizophrenia, but the clinician should assume that there is an organic basis when an elderly individual begins to develop visual hallucinations for the first time. Representative cases that illustrate visual hallucinations due to ophthalmological, vascular, or degenerative processes are presented. Visual hallucinations can be linked to disorders in multiple parts of the nervous system. Even when related to medications, dementia may also be contributory, as is illustrated by the hallucinations seen in those with Parkinson's disease. Treatment of visual hallucinations is treatment of the underlying cause although some newer drugs such as clozapine may also be helpful for selected patients.

Aged↗
PubMed1991

Hypnotically induced auditory hallucinations and the mouth-opening maneuver: a failure to duplicate findings.

OBJECTIVE: The authors sought to replicate the part of a study by Bick and Kinsbourne in which hypnotically induced auditory hallucinations in normal volunteer subjects were abolished by requiring the subjects to open their mouths. METHODS: Sixty-four normal volunteer subjects were hypnotized, and an attempt was made to induce auditory hallucinations. The subjects in whom hallucinations were successfully induced were then asked to perform the mouth-opening maneuver and the control maneuvers of putting their fingers in their ears or squeezing their eyes shut in an effort to end the hallucinations. RESULTS: Sixteen subjects reported having hallucinations. None of them reported that a hallucination was abolished by opening the mouth or closing the eye; four reported ending hallucinations by putting their fingers in their ears. CONCLUSIONS: Opening the mouth does not affect auditory hallucinations induced by hypnosis in normal persons. The most likely reason for the discrepancy between the results of this experiment and those of the Bick and Kinsbourne study is that the design of the latter study was faulty because it permitted demand characteristics to influence the results.

Adult↗
PubMed1992

Toward a brain map of auditory hallucinations.

OBJECTIVE: This study asks whether auditory hallucinations are reflected in a distinctive metabolic map of the brain. METHOD: Regional brain metabolism was measured by positron emission tomography with [18F]-fluorodeoxyglucose in 12 DSM-III schizophrenic patients who experienced auditory hallucinations during glucose uptake and 10 who did not. All patients were free of neuroleptics and 19 had never been treated with neuroleptics. Nine patients were reexamined after 1 year to assess effects of neuroleptic treatment. RESULTS: Compared with the patients who did not experience hallucinations, the patients who did experience hallucinations had significantly lower relative metabolism in auditory and Wernicke's regions and a trend toward higher metabolism in the right hemisphere homologue of Broca's region. Hallucination scores correlated positively and significantly with relative metabolism in the striatum and anterior cingulate regions. Neuroleptic treatment resulted in a significant increase in striatal metabolism and a reduced frontal-parietal ratio, which was significantly correlated with a decrease in hallucination scores. CONCLUSIONS: Auditory hallucinations involve language regions of the cortex in a pattern similar to that seen in normal subjects listening to their own voices but different in that left prefrontal regions are not activated. The striatum plays a critical role in auditory hallucinations.

Adult↗
PubMed1997

Auditory hallucinations and the temporal cortical response to speech in schizophrenia: a functional magnetic resonance imaging study.

OBJECTIVE: The authors explored whether abnormal functional lateralization of temporal cortical language areas in schizophrenia was associated with a predisposition to auditory hallucinations and whether the auditory hallucinatory state would reduce the temporal cortical response to external speech. METHOD: Functional magnetic resonance imaging was used to measure the blood-oxygenation-level-dependent signal induced by auditory perception of speech in three groups of male subjects: eight schizophrenic patients with a history of auditory hallucinations (trait-positive), none of whom was currently hallucinating; seven schizophrenic patients without such a history (trait-negative); and eight healthy volunteers. Seven schizophrenic patients were also examined while they were actually experiencing severe auditory verbal hallucinations and again after their hallucinations had diminished. RESULTS: Voxel-by-voxel comparison of the median power of subjects' responses to periodic external speech revealed that this measure was reduced in the left superior temporal gyrus but increased in the right middle temporal gyrus in the combined schizophrenic groups relative to the healthy comparison group. Comparison of the trait-positive and trait-negative patients revealed no clear difference in the power of temporal cortical activation. Comparison of patients when experiencing severe hallucinations and when hallucinations were mild revealed reduced responsivity of the temporal cortex, especially the right middle temporal gyrus, to external speech during the former state. CONCLUSIONS: These results suggest that schizophrenia is associated with a reduced left and increased right temporal cortical response to auditory perception of speech, with little distinction between patients who differ in their vulnerability to hallucinations. The auditory hallucinatory state is associated with reduced activity in temporal cortical regions that overlap with those that normally process external speech, possibly because of competition for common neurophysiological resources.

Adult↗
PubMed2000

Occipital atrophy is associated with visual hallucinations in Alzheimer's disease.

In this study of patients with Alzheimer's disease (AD), patients with visual hallucinations were compared with patients who did not have visual hallucinations to determine if selective occipital lobe atrophy is associated with visual hallucinations. Seven AD patients with visual hallucinations were matched by cognitive score to 7 AD patients without visual hallucinations and 3-D MRI images obtained. A ratio of measured occipital volumes to whole brain volumes was compared between the two groups. AD patients with visual hallucinations had a significantly smaller occipital/whole brain ratio than AD patients without visual hallucinations. These results suggest visual hallucinations in AD may be associated with neuropathology of the occipital lobe.

Aged↗
PubMed1996

Visual hallucinations in a geriatric psychiatry clinic: prevalence and associated diagnoses.

Visual hallucinations are associated with a variety of psychiatric, medical, neurologic, and ophthalmologic disorders. One hundred forty outpatients presenting to a geriatric psychiatric clinic were screened for visual hallucinations and assessed on a number of descriptive variables, medical history, ophthalmologic history, psychiatric diagnosis, and cognitive score. The data revealed that 14 patients (10%) experienced visual hallucinations. Presence of visual hallucinations was significantly associated with diagnoses of dementia or delirium, living in a nursing home, lower cognitive score, and presence of auditory hallucinations and delusions. There was no association to number of medications, age, gender, or presence of eye disease. No patient had "insight' into their visual hallucinations. Despite the numerous disorders that are associated with visual hallucinations, the most common causes in a geriatric psychiatry clinic are dementia and delirium. Clinicians assessing older patients with visual hallucinations should first carefully evaluate for these disorders.

Aged↗
PubMed1990

Regional brain metabolism during auditory hallucinations in chronic schizophrenia.

Regions of the brain involved in language and attention were studied using [18F]-fluorodeoxy-glucose in PET. In nine chronic DSM-III schizophrenic patients who had persistent auditory hallucinations, ten who had recovered from hallucinations and ten normal controls. In none of the regions examined was metabolic activity significantly different in hallucinating patients compared with that in other groups. However, a pattern of seven significant correlations of metabolic activity between language regions and between frontal and parietal cortex characterised the hallucinating but not the other groups. Three of the seven correlations were significantly greater in hallucinating patients than in the two other groups, and six were greater in hallucinating patients than controls. Metabolism in Broca's region and its right-hemisphere homologue correlated positively and significantly in the hallucinating group, as it did in anterior cingulate and left superior temporal areas, and in right frontal and parietal areas. Hallucination ratings correlated with metabolism in the anterior cingulate region.

Adult↗