Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Hallucinations”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18Linked to original sources
PubMed1994

[Visual hallucination in the hemianopic field caused by dural arteriovenous malformation].

We presented a 65-year-old man with the right occipital dural arteriovenous malformation (AVM) who first experienced photopsia in his left inferior quadrantanopic field and then developed formed hallucinations 8 days later. His visual hallucinations disappeared with saccadic eye movements. EEG showed no epileptic discharge. MRI revealed hyperintensity in the right medial occipital lobe on proton density image. 123I-IMP SPECT during the hallucinations revealed decrease of regional cerebral blood flow (r-CBF) not only in the right medial occipital lobe but also in the right lateral occipital and in the right medial temporal lobe. Both left inferior quadrantanopia and visual hallucinations disappeared following the treatment of the dural AVM by transarterial embolizations. Because the lesion on MRI improved after the treatment, we considered that the lesion was brain edema, not infarction. Additionally decreased r-CBF in the temporo-occipital lesion on SPECT improved after the treatment, we emphasized the role of the temporo-occipital lesion as the cause of visual hallucinations in the hemianopic field.

Aged↗
PubMed1993

[Musical hallucinations: 7 cases].

Musical hallucinations (MH) occurred in 7 patients (5 women and 2 men, age 58-90 yrs) with mild to severe unilateral or bilateral deafness. The hallucinations usually consisted of musical memories (childhood songs, past "hits"). They started abruptly and were identified, sometimes after a period of doubt, as hallucinations. They became "louder" in the silence and, when iterative, could be distressing. By concentrating, 3 patients could change the ongoing tune for another. Elementary (1 case) or verbal (3 cases) auditory hallucinations could be associated and, in one case, vivid visual hallucinations occurred which were not criticized. One patient suffered depression and the MH faded after antidepressive treatment. In the other cases, no psychiatric disorder was identified. Neurological examination, EEGs and brain MRI (in 5 cases) were normal in all but one case, in which MH followed seizures secondary to a left parietal metastasis. Such MH may be termed hallucinosis according to Ey's description. They share some characteristics with other hallucinatory phenomena associated with sensory deprivation, such as the Charles Bonnet syndrome and "pain memories" in phantom limbs. However, the role of deafness, the underlying central mechanisms and psychological factors are poorly understood.

Aged↗
PubMed1996

Dangerousness and command hallucinations: an investigation of psychotic inpatients.

Forensic consultations with psychotic inpatients frequently include issues of risk management, such as dangerousness and civil commitment. An important dimension of these consultations is the role of command hallucinations in producing an increased risk of aggressive behavior. In the present study, psychotic patients with command hallucinations (N = 27) were compared with patients with other hallucinations (N = 27) and with other psychotic patients (N = 30). The groups did not differ on aggressive behavior or most nonhallucinatory symptoms. However, most patients (84.0%) with command hallucinations had recently obeyed them. Among those with command hallucinations, almost one-half had heard and attempted to obey messages of self-harm during the last month.

Adult↗
PubMed2005

Source monitoring for actions in hallucination proneness.

INTRODUCTION: In the present study we explored the role of cognitive factors in hallucinatory proneness by utilising an incidental source monitoring task consisting of actions. METHOD: A total of 65 normal subjects were administered a source monitoring task and were asked either to: (1) perform the action; (2) watch the experimenter perform the action; (3) imagine him/herself performing the action; (4) imagine the experimenter performing the action; (5) or listen to the experimenter say the action verbally. Following a delay, actions were presented consisting of those already presented in one of the 5 conditions (old), and those never before presented (new). For each action, subjects were required to identify if the action was old or new. If the action was identified as old, subjects were required to identify the source of the word (i.e., one of the 5 conditions). Subjects also completed a questionnaire assessing metacognitive beliefs. Subjects were grouped according to their scores on a revised and elaborated version of the Launay-Slade Hallucinations Scale (LSHS). Those with scores within the top 25% were included in the hallucination-prone group (HP) (n = 16), whereas scores within the lower 25% were included in the nonhallucination-prone group (NHP) (n = 16). RESULTS: Within the internal conditions, hallucination-prone subjects confused two internal sources (a specific internal-internal source discrimination error). That is, for imagined actions where the subjects performed the action, HP subjects erroneously attributed these towards an imagined action performed by the experimenter. Results also revealed that hallucination-proneness was associated with metacognitive beliefs. Finally, there was a significant relation between certain metacognitive beliefs and the internal-internal source discrimination error on the source monitoring task. CONCLUSIONS: Findings from the present study suggest that an important cognitive deficit in the genesis of hallucinations may be a perturbation in the control of internally generated cognitive events.

Journal Article↗
PubMed1976

Asymmetry of information processing in hallucinators and nonhallucinators.

In previous work we had developed evidence suggesting that hallucinating schizophrenics differ from nonhallucinators in the pattern of errors made in a shadowing task. Non hallucinators appeared to be less willing to guess when they were unsure. The errors of the hallucinators seemed more semantically elaborate. The experiment had not been designed to study these factors and the current experiment was conducted using a technique reported by Pisoni et al. These workers had studied normal Ss in an immediate recall task, using semantically well integrated (SWI) or poorly integrated (SPI) sentences. Pisoni et al. had shown that right ear presentation produced more accurate recall of SWI as compared to SPI sentences, whereas left ear presentation failed to discriminate these sentences. Utilizing the methods of Pisoni et al., we replicated their findings in a normal control group. The results from our hallucinating and nonhallucinating groups were different from each other, the nonhallucinators being less accurate, discriminating semantic integration level on left rather than right ear input, and making more fragmented errors. Little support could be found for attributing this pattern of performance to nonspecific aspects of the procedures. It appears that the nonhallucinators process information differently from hallucinators. These differences may reflect alterations in language development. It is speculated that such differences might be consistent with interference with the development of brain asymmetry.

Age Factors↗
PubMed1993

Auditory-verbal hallucinations and the phonological loop: a cognitive neuropsychological study.

A patient with continuous auditory-verbal hallucinations was studied, in comparison with two cases with a past history of similar hallucinations, from a cognitive neuropsychological perspective. This attempts to place hallucinations in the context of a normal cognitive process which has become disordered. The process in question is the phonological loop, equivalent to inner speech, derived from a model of short-term or working memory. A series of short-term memory tests, assumed to rely on the adequate functioning of the phonological loop, was administered, the results of which broadly conformed to a normal pattern of performance. It is concluded that verbal hallucinations cannot be regarded as involving the phonological loop directly. Other points in the short-term memory/language system at which verbal hallucinations could arise are discussed, as are suggestions for further research of this kind.

Adult↗
PubMed1977

Quadruplet hallucinations. Phenotypic variations of a schizophrenic genotype.

This article provides an in-depth analysis of hallucinations in monozygous quadruplets concordant for schizophrenia. Since all four are genetically identical, deviations among them with regard to various aspects of hallucinations probably represent the effects that nongenetic factors can produce in hallucinating schizophrenics. Concordance probably represent the effects of genetic factors. We present here findings based on this research strategy, and a brief review of the literature on hallucinations.

Adult↗
PubMed2002

Olanzapine treatment for dopaminergic-induced hallucinations.

Atypical antipsychotic medications with lower affinities for D2 receptors are considered useful alternatives to treat drug-induced hallucinations in Parkinson's disease (PD). We conducted a double-blind, placebo-controlled, unforced titration, parallel design study (2:1 drug to placebo randomization ratio) using olanzapine (2.5-10 mg/day to effect) in 30 PD patients with drug-induced hallucinations. We performed an extensive battery of neuropsychological tests, the Unified Parkinson's Disease Rating Scale (UPDRS), assessments of on and off time at baseline and at 9 weeks after starting the medication. Sixteen patients on olanzapine (mean dose, 4.6 mg/night) and 11 on placebo completed the study. Compared with placebo, performance on the UPDRS item 2 (thought disorder), and a structured interview for hallucinations, both tended to improve on drug but neither reached statistical significance. A neuropsychological test battery did not show any significant differences. Total on UPDRS motor scores (P < 0.05) and timed tapping (P < 0.01) worsened while on drug compared to placebo. Bradykinesia (P < 0.01) and gait (P < 0.001) items on the UPDRS largely accounted for this deterioration. After completion of the study, 8 of 16 patients randomly assigned to drug continued olanzapine at a mean dose of 2.4 mg/day. However, at the last recorded visit only 5 of 24 (20.8%) of all patients exposed to drug (including those originally randomly assigned to placebo) remained on olanzapine. In patients with PD, low-dose olanzapine did not significantly improve hallucinations but did worsen motor function.

Aged↗
PubMed1998

Steady state visually evoked potential correlates of auditory hallucinations in schizophrenia.

This study attempted to localize regions of brain electrical activity associated with the onset of auditory hallucinations. Changes in Steady State Visually Evoked Potential (SSVEP) topography associated with the onset of spontaneous auditory hallucinations was studied in eight schizophrenic patients. The SSVEP elicited by a spatially uniform sinusoidally varying visual flicker was recorded using a 64-channel electrode helmet. A large and significant decrease in SSVEP latency in the right temporo/parietal region occurred in the second prior to the report of auditory hallucinations. A control task with matching motor movements produced no significant decrease in SSVEP latency in the same right temporo/parietal location. This finding suggests that activity of fine temporal resolution in the neural networks in the right temporo/parietal area may be implicated in the genesis of auditory hallucination, in conformity with certain neuropsychological theories.

Adult↗
PubMed1991

Peduncular hallucinations.

Peduncular hallucinations usually present as visual disorders and are often genuine hallucinations associated with thalamic and/or mesencephalic lesions. In this case report we describe the clinical findings in a patient with hallucinations. Magnetic resonance imaging demonstrated bilateral ischaemic lesions in the thalamus and in the mesencephalon. The pathogenesis of hallucinations in these disorders is discussed in the light of the findings provided by imaging techniques.

Cerebral Infarction↗
PubMed1996

Salsolinol, catecholamine metabolites, and visual hallucinations in L-dopa treated patients with Parkinson's disease.

We could quantify the tetrahydroisoquinoline derivative salsolinol in urine of patients with Parkinson's disease and normal control subjects by means of high performance liquid chromatography and electrochemical detection. Urine levels of salsolinol were positively related to the homovanillic acid/3-O-methyl-dopa ratio in the cerebrospinal fluid that reflects dopamine metabolism. In the patient group with visual hallucinations, mean salsolinol level was significantly increased to almost the 3-fold of those found in patients without hallucinations. Since the daily L-dopa doses of both patient groups were nearly identical this result is not due to different L-dopa medications. Additionally, either high values of the main serotonin metabolite, 5-hydroxyindole acetic acid (HIAA) or the L-dopa/3-O-methyl-dopa ratio were found in cerebrospinal fluid of patients with hallucinations. The enhanced salsolinol levels in patients with visual hallucinations seem to be due to an overloaded dopaminergic pathway with an imbalance between dopaminergic and serotonergic systems. Thus, salsolinol appears as a predictor for hallucinosis in Parkinson's disease.

Aged↗
PubMed1987

Visual hallucinations in ophthalmology.

Forty-three patients with severe visual impairment due to bilateral eye disease were assessed for visual hallucinations, 28 of them after eye surgery. Ages ranged between 65 and 93 years and none of the patients had any psychiatric disorder. Five of the 43 patients were diagnosed as cases with Charles Bonnet syndrome reporting visual hallucinations that had developed in the course of sight deterioration. There was strong indication that sensory deprivation was an essential pathogenetic factor for this phenomenon. Three of the 28 patients assessed following eye surgery who had no history of hallucinatory phenomena experienced visual hallucinations on the 2nd postoperative day without showing any other psychiatric symptoms. The various conditions associated with visual hallucinations are discussed that may be of relevance to the ophthalmologist.

Aged↗
PubMed1993

Left superior temporal blood flow increases in schizophrenic and schizophreniform patients with auditory hallucination: a longitudinal case study using 123I-IMP SPECT.

Serial assessments of regional cerebral blood flow were performed using 123I-IMP SPECT in two schizophrenic and three schizophreniform patients with persistent auditory hallucination. The initial SPECT study in the period with prominent auditory hallucination revealed an increased accumulation of 123I-IMP in the left superior temporal area which corresponded to the auditory association cortex. In the follow-up SPECT study performed after clinical improvement, the distribution of 123I-IMP had normalized. One of the case with schizophrenia showed a similar increased uptake of 123I-IMP in the left superior temporal area in the third SPECT scan performed when a psychotic relapse with auditory hallucination occurred. MRI scans in two of the five patients demonstrated reduced volume of the temporal lobes. These findings suggest that the auditory hallucinations in schizophrenia may be involved in functional hyperactivity in the left superior temporal cortex which might be based partly on structural abnormalities in the temporal lobes.

Adult↗
PubMed2004

Associations between visual and auditory hallucinations in children and adolescents, and tobacco use in adulthood.

AIMS: The cross-sectional association between tobacco use and psychotic features has been well established. If psychotic features precede tobacco use, then tobacco may be used to self-medicate psychotic symptoms. The aim was to assess if psychotic features in adolescents constitute a risk factor for later tobacco use. DESIGN: A random target sample of 2,600 children aged 4-16 years from the Dutch general population was followed up across a 14-year interval. At different ages (childhood, adolescence, young adulthood), information about visual and auditory hallucinations was obtained using standardized questionnaires for parents and subjects themselves. At outcome (ages 18-30), tobacco use was assessed. FINDINGS: Auditory hallucinations, but not visual hallucinations, in early and late adolescence, assessed via parents and adolescents themselves, predicted tobacco use in adulthood. CONCLUSIONS: The present study confirmed that auditory psychotic features in adolescence are associated with tobacco use in adulthood. Tobacco may be used to self-medicate auditory, but not visual, hallucinations.

Adolescent↗
PubMed2005

Regional cerebral blood flow change in a case of Alzheimer's disease with musical hallucinations.

We examined alteration of regional cerebral blood flow (rCBF) in a case of Alzheimer's disease (AD) patient with musical hallucination. To detect regions related to musical hallucination, single-photon emission computed tomography (SPECT) imaging of the patient and nine sex, age, and cognitive function-matched AD patients without delusions and hallucinations were compared using statistical parametric mapping 99 (SPM99). In comparison with controls, the patient had increased rCBF in left temporal regions and left angular gyrus. This profile could be relevant to the neuroanatomical basis of musical hallucinations.

Aged↗
PubMed2003

Hallucinating the past: a case of spontaneous and involuntary recall of long-term memories: perspectives on the hemispheric organization of visual memory.

This paper presents the unique case of a patient who developed palinopsias and formed visual hallucinations, representing spontaneous recall of memories from a discrete 10-year time period. The visual phenomena began shortly after the initiation of prophylactic whole-brain radiation therapy, following the removal of a metastatic adenocarcinoma in the region of the right cuneus. The most striking feature of this patient's hallucinations is the composition: memories from a discrete 10-year time period from about 30 years ago. This case provides further evidence to support the theory of a contralateral and hemispheric organization of visual memory. We propose that visual memory traces formed nearly three decades ago were spontaneously recalled in the form of hallucinations and palinopsias. It is noteworthy that the region of the brain most affected by the tumor and subsequent radiation therapy is postulated to permit perception of mental imagery. To our knowledge, no other case involving hallucination of 30-year-old memories has been reported.

Adenocarcinoma↗
PubMed2006

Musical hallucinations in a musician.

The experience of music is difficult to study objectively. Here we describe a detailed analysis of musical hallucinations developing after a probable brainstem stroke in an 83 year old musician who was able to describe and notate the hallucinations. The hallucinations comprised simple, repetitive melodic and rhythmic motifs that were combined apparently randomly without definite tonality, large-scale structure, or timbre. This observation is consistent with the proposal that musical hallucinations represent abnormal spontaneous activity in auditory cortical areas beyond the primary auditory cortex. This activity may generate novel musical motifs.

Aged, 80 and over↗
PubMed1999

Medication-induced hallucination and cerebral blood flow in Parkinson's disease.

Although hallucinations in Parkinson's disease (PD) are not unusual in the long-term treatment with anti-parkinsonian agents, their mechanism is not fully understood. We compared both the neuropsychiatric state and the results of 99mTc-labeled hexamethyl propyleneamine oxime single-photon emission computed tomography in 12 PD patients with medication-induced hallucinations and 21 PD patients without hallucinations. Hallucinatory patients showed significantly lower cerebral blood flow in left temporal regions than nonhallucinatory patients. The cerebral blood flow reduction in these regions may be related to the mechanism of medication-induced hallucinations in PD.

Aged↗