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Transient formed visual hallucinations following macular translocation for subfoveal choroidal neovascularization secondary to age-related macular degeneration.

PURPOSE: To report the occurrence of transient formed visual hallucinations following macular translocation. METHODS: Two case reports. RESULTS: Two white women aged 84 and 83 years with bilateral age-related macular degeneration and unilateral subfoveal choroidal neovascularization underwent macular translocation with punctate retinotomy (limited macular translocation) and chorioscleral infolding in the eye with neovascularization. They complained of formed visual hallucinations which began within 24 hours following macular translocation and ceased 7 and 3 days postoperatively, respectively. Their symptoms occurred in the presence of normal cognition, orientation and insight, were not associated with other psychiatric symptoms, and were characteristic of Charles Bonnet syndrome (CBS). CONCLUSION: The temporary deliberate retinal detachment and/or poor vision following macular translocation may be associated with postoperative CBS, and this report extends the spectrum of conditions associated with CBS.

Aged↗

Reduced frontotemporal functional connectivity in schizophrenia associated with auditory hallucinations.

BACKGROUND: We used functional magnetic resonance imaging (fMRI) to investigate the frontotemporal disconnection hypothesis of schizophrenia. METHODS: Eight DSM-IV schizophrenia patients and 10 control subjects were studied with fMRI while they thought of the missing last word in 128 visually presented sentences. The fMRI data were analyzed comparing the effect of sentence completion (vs. rest) using a random effects analysis. RESULTS: There were no significant group differences in regional brain responses. Correlation coefficients between left temporal cortex (x = -54, y = -42, z = 3) and left dorsolateral prefrontal cortex (x = -39, y = 12, z = 24) were significantly lower in the schizophrenic group and were negatively correlated with the severity of auditory hallucinations. CONCLUSIONS: Previous demonstrations of hypofrontality in schizophrenia may reflect particular task requirements. Frontotemporal functional connectivity is reduced in schizophrenia and may be associated with auditory hallucinations.

Adult↗

Underconstrained perception: a theoretical approach to the nature and function of verbal hallucinations.

We do not see the world as it is. Perception forms a subjective image of the world in a language that has proven to be adaptive to our interaction with the external world. Perception is mainly determined by current needs of the organism and goals of behavior. Sensory processing itself does not culminate in perception and is not essential for perception, since perception derives from representations of internal symbols and their features. The current stimulation of sensory organs does, however, constrain our perception. Perception might be less constrained by the external world in cases of (1) increased attention, (2) decreased sensory stimulation, or (3) facilitated formation of cortical associations between representations of expectations and internal symbols. Hallucinations are perceptions that are underconstrained by external sensory stimulation. Verbal hallucinations that allow the patient to infer about his self-image might constitute the core psychopathology in a subset of schizophrenia. Commenting and discussing voices might be perceived under the pressure of increased attention to environmental factors that relate to the patient's social fears and wishes. Secondarily, delusions about the possession of thoughts and disorders of self-experience may develop.

Association↗

[Guillain-Barré syndrome with hallucinations and onirism: an underestimated association].

INTRODUCTION: Guillain-Barré Syndrome (GBS) is generally related to peripheral nervous system involvement, but certain variants with central nervous system manifestations have been described. CASE REPORT: In the present study we report 2 patients with GBS associated with hallucinations and onirism. Two men (age 64 and 49 years) presented GBS without proven infectious origin who required intensive care because of respiratory problems. The disease progressed and manifestations of encephalitis (hallucinations and onirism) appeared. The sensorimotor signs and encephalitis manifestations evolved in parallel with full recovery in the first patient and death after 11 months of intensive care in the second. CONCLUSION: GBS may be associated with stereotypic central nervous system symptoms, mimicking delirium tremens. The manifestations would be related to the severity of the initial period, but not to long-term prognosis.

Adult↗

Auras and other hallucinations: windows on the visual brain.

Hallucinations in psychologically normal individuals provide a valuable route to studying the neural mechanisms of visual awareness. Migraine auras, epileptic auras and the hallucinations of Charles Bonnet Syndrome are examined in this context. Both similarities and striking differences in content are noted and the extent to which we are currently able to localize the source of these forms of endogenously driven visual awareness is discussed.

Brain↗

Characteristics of the psychoses of late onset in children and adolescents (a comparative study of hallucinating children).

In a retrospective design, 20 children and adolescents with psychoses of late onset and hallucinations were compared with 20 children with conduct or emotional disorders who also had hallucinations. Marked differences emerged between the two groups. Psychotic subjects showed significantly more delusions, abnormalities in language production, inappropriate affect, bizarre behaviour, hypoactivity, and social withdrawal. Some subjects had symptoms which indicated a specially profound breakdown in personality functioning, but schneiderian and other schizophrenic symptoms were relatively rare. This questions their diagnostic value in the psychoses of late onset of children and adolescents.

Adolescent↗

[Adaptation to central scotoma. III. Visual hallucinations and Charles Bonnet syndrome].

Patients with low vision due to central scotoma may experience complex visual hallucinations, referred to as Charles Bonnet syndrome. The present review reports the current literature on this syndrome and details its frequency, predisposing circumstances, the nature of the hallucinations, and treatments. It also reports the possible occurrence of the syndrome immediately after macular treatments using laser photocoagulation and photodynamic therapy. Patients should be reassured when they experience this syndrome, which is not severe but may be the cause of patient concern.

Adaptation, Physiological↗

[Musical hallucinations].

Musical hallucinations are rarely reported. Acquired deafness play an important role in their development. The anatomical and neurophysiological substrates for the musical hallucinations are unknown. Most authors related the perceptual disturbance to organic origin (central or peripheral).

Aged↗

Clarithromycin-associated visual hallucinations in a patient with chronic renal failure on continuous ambulatory peritoneal dialysis.

Visual hallucinations are a rare event in chronic renal failure and not related to uremia per se. Unreported in the literature is visual hallucinations occurring in association with the new macrolide antibiotic, clarithromycin. We describe such a case in a patient with end-stage renal disease (ESRD) maintained on continuous ambulatory peritoneal dialysis (CAPD). The combination of a relatively high dose of clarithromycin in face of chronic renal failure in a functionally anephric patient, with underlying aluminum intoxication, may have facilitated the appearance of this neurotoxic side effect. It is important to understand the pharmacokinetics of medications in face of chronic renal failure, the possibility of drug interactions, and how these factors should help guide medication therapy in the ESRD patient.

Anti-Bacterial Agents↗

Individual cognitive-behavior therapy in the treatment of hallucinations and delusions: a review.

The limitations of biochemical treatments in reducing the severity of hallucinations and delusions has led to an increased interest in the investigation of psychological treatments for these symptoms. These investigations have spanned the last 4 decades and have covered a range of psychological approaches from psychoanalytically oriented psychotherapy to behavioral approaches. More recently, findings that some psychotherapies are not effective treatments for psychosis and that cognitive-behavior therapy can be an effective treatment for neurotic disorders have led to increasing interest in the investigation of the effectiveness of cognitive-behavior therapy for psychosis. This review describes and evaluates the research on the cognitive-behavioral treatment of hallucinations and delusions and describes the cognitive models from which the treatments have developed. The conclusion is that, on the whole, the literature provides fairly strong evidence for the efficacy of cognitive-behavioral approaches in the management of chronic psychotic disorders and associated symptoms, although there are a number of areas where further development is necessary.

Adaptation, Psychological↗

Visual hallucinations in a toddler: accidental ingestion of a sympathomimetic over-the-counter nasal decongestant.

Hallucinations are uncommonly encountered in the young child. The differential diagnosis of such behavior includes a number of potentially serious syndromes such as central nervous system malignancy, encephalitis, temporal lobe epilepsy, closed head trauma with frontal lobe confusion, hypoglycemia, drug intoxications, and childhood psychiatric syndromes. Organic explanations are most often discovered and frequently involve toxicologic causes. A case is presented of a toddler with hallucinations caused by inappropriately high doses of pseudoephedrine.

Bronchodilator Agents↗

Antiepileptic drug-induced visual hallucinations in a child.

The neurologic signs and symptoms of carbamazepine and phenytoin toxicity, such as ataxia, dysarthria, and nystagmus, are well known. The psychiatric manifestations of toxicity, such as psychosis and hallucinations, however, are less widely recognized. This study reports the case of a 9-year-old male with seizures who developed intermittent complex visual hallucinations after therapy with antiepileptic drugs was begun. This study considered seizures, migraine, underlying psychiatric diathesis, and drug toxicity as possible etiologies but after extensive investigation concluded that his symptoms were most likely a drug side effect.

Anticonvulsants↗

Reduced corticocortical connectivity can induce speech perception pathology and hallucinated 'voices'.

Reciprocal interactions between multiple cortical areas are required for higher-order cognitive processes in animals and humans. A growing body of evidence suggests that reduced cortical connectivity is associated with schizophrenia. We have used neural network computer simulations to characterize symptoms and cognitive pathology that could arise from connectivity reductions. When this pathology was reproduced in simulations of speech perception networks, spontaneous percepts analogous to hallucinated speech were induced due to the emergence of 'locked-in' or 'parasitic' states. We propose that these simulations provide a model for hallucinated 'voices' reported by actual schizophrenic patients. The 'hallucinogenic' model of speech perception also demonstrated subtle speech perception impairments. We have demonstrated similar impairments when assessing schizophrenic patients reporting 'voices', but not when assessing similarly diagnosed patients not reporting this symptom. The model also demonstrates how a 'hypodopaminergic' state can reverse cognitive pathology arising from connectivity disturbances.

Cerebral Cortex↗

Auditory hallucinations: a review of psychological treatments.

Auditory hallucinations (AH) occur frequently amongst psychiatric patients, being most common in schizophrenia. In 25-30% of cases they are refractory to traditional antipsychotic drugs. A variety of psychosocial treatments have been used, but their efficacy remains unclear. This review aims to bring together the more recent studies of psychological treatments and discuss them in the context of recent cognitive models of hallucinations and functional imaging studies. The search strategy included the following sources: MEDLINE, Embase and Psychlit. Strategies reported by patients can be categorised as: (1) distracting activities, such as listening to music; (2) behavioural tasks, such as taking exercise; (3) cognitive tasks, such as ignoring AH. Almost all the strategies produced some benefit in some patients: treatment often improved AH-associated distress, rather than frequency of AH. There are many difficulties in conducting research on AH. Treatment should be individually tailored and used as an adjunct to pharmacotherapy. Future theory-driven studies need to be based on complex aetiological models and incorporate functional imaging to elucidate the physiological changes induced by therapeutic interventions.

Antipsychotic Agents↗

Further evidence of the multi-dimensionality of hallucinatory predisposition: factor structure of a modified version of the Launay-Slade Hallucinations Scale in a normal sample.

Recent years has seen an increasing interest in the hallucinatory experience, including investigations of its phenomenological prevalence and character both in pathological and normal (predisposed) populations. We investigated the multi-dimensionality of hallucinatory experiences in 265 subjects from the normal population, who completed a modified version of the Launay-Slade Hallucinations Scale. Principal components analysis was performed on the data. Four factors were obtained loading on items reflecting (1) sleep-related hallucinatory experiences (2) vivid daydreams (3) intrusive thoughts or realness of thought and (4) auditory hallucinations. The results offer further evidence of the multi-dimensionality of hallucinatory disposition in the normal population. Directions for future research in hallucinatory predisposition are discussed.

Adult↗

Seeing is believing: the reality of hypnotic hallucinations.

Two experiments investigated the reality attributed to hypnotic suggestion through subtle projection of a visual image during simultaneous suggestion for a visual hallucination that resembled the projected image. In Experiment 1, high and low hypnotizable participants were administered either a hypnotic induction or wake instructions, given a suggestion to hallucinate a shape, and then the projected image was subsequently introduced. Although highs in both conditions rated the projected image more vividly than lows, highs in the hypnosis (but not wake) condition made comparable reality ratings when the projected image was absent and present. In Experiment 2, high hypnotizable participants were administered a suggestion to see a shape on a wall. For half the participants the suggested image was projected on the wall and then removed, and for half the projection was initially absent and then introduced. Participants who had the projection absent and then present reported comparable reality and vividness ratings when the projection was absent and present. These findings indicate that elevated hypnotizability and hypnosis are associated with attributions of external reality to suggested experiences.

Adolescent↗

Self-monitoring in speech production: effects of verbal hallucinations and negative symptoms.

This paper reports results of a study on self-monitoring in speech production. Thirty schizophrenics, varying in verbal hallucination and in negative symptoms status, and 17 controls were tested on the reporter test. The position of interruptions of the speech-flow to repair errors was used to indicate whether the detection of the errors was through monitoring of internal phonetic plans or through external acoustic feedback. We have found that the internal error detection was twice as frequent in controls as in schizophrenics. The relevance of this finding to Frith's (1992) model of schizophrenia is discussed. Our conclusion is that the problem with internal monitoring of phonetic plans is common to all schizophrenics, and not just to those with verbal hallucinations.

Adolescent↗