Visual hallucinations and mental state. A study of 14 Charles Bonnet syndrome hallucinators

Visual Impairment and Mental Health: Unmet Needs and Treatment Options

Purpose

An estimated 2.2 billion people are visually impaired worldwide. Given that age-related vision loss is a primary cause of vision impairment, this number is projected to rise with increases in average lifespan. Vision loss often results in significant disability and is associated with a substantial economic burden, reduced quality-of-life, concurrent medical issues, and mental health problems. In this review, the mental health needs of people with vision impairment are examined.

Patients and methods

A review of recent literature on mental health outcomes and current treatments in people with visual impairment was conducted.

Results

Considerable data indicate that rates of depression and anxiety are elevated among people with visual impairments. Moreover, individuals of lower socioeconomic status may be at increased risk for vision impairment and subsequent mental health problems. Existing psychosocial interventions for improving mental health in people with visual impairment show some promise, but are limited by low adherence and lack generalizability.

Conclusion

In order to improve outcomes, a better understanding of the mechanisms linking visual impairment and poor mental health is needed. It will also be essential to develop more effective interventions and expand access to services to improve the detection and treatment of mental health problems in this population.

Evaluation of the Clinical Features, Management, and Prognoses of Patients With Charles Bonnet Syndrome

Charles Bonnet syndrome (CBS) is characterized by visual hallucinations with preservation of cognitive abilities. The hallucinations consist mostly of vivid (realistic) objects and tend to reoccur. Here, we evaluate the etiologies, symptoms, treatments, and prognoses of 13 CBS cases. All patients had visual hallucinations but were normal on cognitive and psychiatric assessments. Patient demographic and clinical characteristics, treatment options, and 3-month follow-up data were retrospectively reviewed. The possible causes of CBS and what the patients perceived during their hallucinations were recorded. Antipsychotic agents, such as risperidone and quetiapine, and anticonvulsants, such as levetiracetam, may be effective in some cases.

Screening for Charles Bonnet syndrome: Should the definition be reconsidered?

Purpose

Charles Bonnet syndrome (CBS) is a condition in which individuals with visual impairment (VI) and with no cognitive deficits experience visual hallucinations, typically with no other sensory hallucinations. Although few isolated case reports of CBS from India have been published, the prevalence for CBS in India is largely unknown. The primary aim of this study was to estimate CBS prevalence in patients with vision impairment visiting a tertiary eye care center.

Methods

The study was conducted in two phases. In phase 1, patients with VI, age ≥40 years with presenting visual acuity worse than 20/63 were enrolled. In phase 2, patients with presenting visual acuity worse than 20/63 and/or with binocular visual field loss, age ≥18 years were recruited. A CBS survey was administered only to those who passed a screening test for cognition impairment.

Results

A total of 218 patients were screened (phase 1 = 113 and phase 2 = 105). Two-hundred ten patients (mean age ± standard deviation = 49.2 ± 17.3 years, males = 139) were found eligible to complete the CBS survey. Fourteen patients were found to have visual hallucinations. In addition, three other patients had visual hallucinations with associated auditory input to the visual imagery. All patients had complete insight about their hallucinations.

Conclusion

Depending on the inclusion criteria, we found the prevalence for CBS in patients with VI to vary between 6.7% to 8.1% (if including patients with auditory input). More investigation is needed to assess the associated role of other sensory inputs (e.g. auditory) with the visual imagery experienced in CBS.

Cognitive impairment and Charles Bonnet syndrome: a prospective study

OBJECTIVES

Charles Bonnet syndrome (CBS) is a common cause of visual hallucinations in older people. The relationship between CBS and cognitive impairment is unclear, but anecdotal reports exist of dementia emerging in patients diagnosed with CBS. This work set out to determine if there is an increased incidence of dementia, and increased severity of cognitive impairment, in people with CBS compared to controls from the same clinical setting.

METHOD

People over 65 attending low-vision and glaucoma clinics, and a cohort of age-matched controls, underwent a psychiatric assessment. The cohorts were followed up after one year.

RESULTS

Mild cognitive impairment was present in 2/12 CBS participants and 2/10 controls. Partial insight was seen in nine CBS participants. Two participants with CBS, and no controls, developed dementia at follow-up. No significant differences in performance on the ACE-R were found between the groups. Both participants who developed dementia had partial insight and hallucinations of familiar figures at diagnosis of CBS, and one had mild cognitive impairment.

CONCLUSIONS

Reassurance that CBS is universally benign may be misplaced. Some people given this diagnosis go on to develop dementia. Cognitive testing at the point of diagnosis was unable to identify those at risk of this outcome. Partial insight, the presence of Mild Cognitive Impairment, and hallucinations of familiar figures at diagnosis of CBS may confer an increased risk of subsequent dementia diagnosis. Copyright © 2017 John Wiley & Sons, Ltd.

Charles Bonnet syndrome and cognitive impairment: a systematic review

ABSTRACT Background: Charles Bonnet syndrome (CBS) is defined as complex persistent visual hallucinations in the absence of mental disorder. It is common in conditions causing significant visual impairment. Many authors advise reassurance, considering the condition benign. However, others have suggested that CBS may in some patients represent the early stages of dementia. This review seeks to systematically examine the evidence for any link between CBS and cognitive impairment. Methods: Literature search using OVID Medline, PsychINFO, and Embase. Results: Three studies where cognitive functioning was the primary focus of the research were found. All were small, did not properly apply diagnostic criteria, and reported conflicting results. Eight other studies commented on cognitive functioning, but none used tests sufficiently sensitive to detect changes seen in early dementia. One hundred and thirty four case reports were scrutinized, and reports found of 16 patients with CBS where dementia emerged. High rates of partial insight at diagnosis of CBS were seen in these patients. Conclusions: There have been no adequately powered studies, using accepted diagnostic criteria, where changes in cognitive functioning were the primary outcome. Existing studies are of limited methodological quality and allow no conclusion regarding a relationship between cognitive impairment and CBS to be reached. Numerous case reports of dementia developing in patients with CBS and partial insight raise the possibility of a link between these conditions. There is a clear need for properly constructed studies to investigate this.

Clinical phenomenology and mortality in Charles Bonnet syndrome

BACKGROUND/AIM

Despite existing diagnostic criteria for Charles Bonnet syndrome (CBS), clinical manifestations vary greatly. We examined the clinical course and mortality of patients diagnosed with CBS.

METHODS

We conducted a retrospective chart review of patients with CBS. We collected demographic and clinical information and medical burden scores. Kaplan-Meier mortality curves were compared using log-rank test. Cox proportional hazard model was used for multivariate analysis and hazard ratio (HR). Mortality was compared to expected mortality from Minnesota population.

RESULTS

Seventy-seven patients with CBS had a mean age of 79.5 (standard deviation ± 13.0) and were predominantly Caucasian (97%) and female (73%). In all, 20 (26%) subsequently developed a dementia syndrome, most often Lewy body. A total of 46 (60%) deaths occurred with an average follow-up time of 33.0 months. Characteristics associated with mortality included older age (75-84 [HR 3.34, P = .029], >85 [HR 4.58, P = .007]) and renal disease (HR 3.39 with 95% confidence interval 1.31-8.80, P = .012). Medical burden scores were not associated with overall mortality. Mortality was high compared to Minnesota population (P < .0001).

CONCLUSIONS

A large proportion of patients with CBS developed dementia, and there was a high mortality rate associated with older age and renal disease. Medical burden was not associated with mortality.

Dermatomal scratching after intramedullary quisqualate injection: correlation with cutaneous denervation

Central nervous system lesions cause peripheral dysfunctions currently attributed to central cell death that compromises function of intact peripheral nerves. Injecting quisqualate (QUIS) into the rat spinal cord models spinal cord injury (SCI) and causes at-level scratching and self-injury. Such overgrooming was interpreted to model pain until patients with self-injurious scratching after SCI reported itch motivated scratching that was painless because of sensory loss. Because self-injurious scratching is difficult to explain by central mechanisms alone, we hypothesized that QUIS injections damage peripheral axons of at-level afferents. QUIS was injected into thoracic spinal cords of 18 Long-Evans rats. Animals were killed 3 days after overgrooming began or 14 days after injection. Spinal cord lesions were localized and DRG-immunolabeled for ATF-3. At-level and control skin samples were PGP9.5-immunabeled to quantify axons. Eighty-four percent of QUIS rats overgroomed. Skin in these regions had lost two-thirds of epidermal innervation as compared with controls (P < .001). Rats that overgroomed had 47% less axon-length than nongrooming rats (P = .006). The presence of ATF-3 immunolabeled neurons within diagnosis-related groups of QUIS rats indicated death of afferent cell bodies. Overgrooming after QUIS injections may not be due entirely to central changes. As in humans, self-injurious neuropathic scratching appeared to require loss of protective pain sensations in addition to peripheral denervation.

PERSPECTIVE

This study suggests that intramedullary injection of quisqualic acid in rats causes death of at-level peripheral as well as central neurons. Self-injurious dermatomal scratching that develops in spinal-injured rats may reflect neuropathic itch and loss of protective pain sensations.

New approaches to understanding hallucinations in Parkinson's disease: phenomenology and possible origins

The authors review current literature on hallucinations in Parkinson's disease (PD). Recent neuropathological studies showed that hallucinations occur in synucleinopathies and are a significant predictor of Lewy Body depositions. Therefore, hallucinations are a hallmark of PD and of dementia with Lewy Bodies. Visual hallucinations are mostly complex and kinematic; preserved or disturbed insight on the nature of hallucinations is a major prognostic factor, although eventually all hallucinators will present with reduced insight. Current theories on the origin of hallucinations point to visual dysfunction, dream overflow and cognitive impairment, yet objection can be raised on each one of the putative models of hallucinations. Understanding of the origin of hallucinations is required in order to develop treatments: all treatment evaluations were focused in general on psychosis, and only clozapine obtained positive evidence-based ratings on efficacy. However, it is likely that cholinesterase inhibitors, antipsychotics and anti-5-hydroxytryptamine(3) agents and drugs acting on sleep regulation will have different and perhaps opposite effects on different types of hallucinations, whether they are accompanied by disturbed insight, sleep disorders or other psychotic features. Further studies will try to separate phenomenology and responses to treatment and will investigate the relevance of concomitant sleep disorders and abnormality of frontoparietal networks involved in the attention process.

Visual hallucinations in Parkinson's disease: clues to separate origins

Our paper discusses two experimental studies suggesting that Visual Hallucinations (VH) in Parkinson's Disease (PD) may have separate origins. The first is a prospective 8years study evaluating the appearance of VH, visual abnormalities assessed by Visual Evoked Potentials (VEPs) and REM sleep Behaviour Disorder (RBD), in 80 PD patients treated with l-Dopa and Dopaminoagonists (DA). In chronically treated, cognitively unimpaired, PD patients VH were statistically related (p=0.001) to RBD occurrence and high DA doses. Visual abnormalities were significantly reduced by l-Dopa or DA intake, and were statistically unrelated to VH. The second study involved PD patients placed in a Virtual Reality Environment, to decontextualize visual input. When motor symptoms worsened and VEP abnormalities developed patients consistently described hallucinatory dysperceptions of the virtual environment. The two studies therefore show that VH can occur in two seemingly distinct conditions, one is related to chronic treatment and to a sleep disorder frequently observed in PD, the other is probably related to a hypodopaminergic state. Our studies support a recently proposed integrative model of VH, and show that the neural circuits purported to explain VH must include the retinal dopaminergic system and the REM sleep regulatory system.

Spatial characteristics of hallucinations associated with sleep paralysis

INTRODUCTION

Spatial properties of hallucinations have received relatively little systematic investigation. We present evidence from a web-based study of the spatial properties of a broad array of hallucinations associated with sleep paralysis. Predictions regarding spatial characteristics of hallucinations were based on proposed neurophysiological mechanisms underlying different types of hallucinations.

METHOD

Distributions in three dimensions as well as distance and dispersion measures were assessed for 279 experient for two general categories of hallucinations: Intruder hallucinations--including presence, visual, and auditory hallucinations; and Vestibular-Motor (V-M) hallucinations--including floating, flying, illusory motor movements, out-of-body experiences (OBEs), and autoscopy.

RESULTS

For all spatial measures, Confirmatory Factor Analysis revealed that Intruder and V-M hallucinations constituted distinctive factors. In addition, Intruder hallucinations were experienced as occurring close to, usually within a meter of, the experient, whereas V-M hallucinations involved excursions of considerable distance, often beyond the immediate environment. V-M hallucination distance was positively associated with vividness of V-M hallucinations, whereas Intruder hallucination distance was negatively correlated with theoretically related contact hallucinations (pressure, obstructed breathing, pain, choking, and touch).

CONCLUSION

The differences in the spatial characteristics of Intruder and V-M hallucinations largely corroborated predictions based on the respective hypothesised neural substrates of a threat activated vigilance system and a bodily-self neuromatrix.

Complex visual hallucinations (Charles Bonnet syndrome) in visual field defects following cerebral surgery

✓ The development of visual hallucinations after loss of vision is known as the Charles Bonnet syndrome. This phenomenon was first described in 1760 by Charles Bonnet and others during their observations of elderly patients with degeneration of the retina or cornea. To date a clear association between visual hallucinations and neurosurgical procedures has not been reported. Because of their clear demarcation, however, surgical lesions in the cerebrum offer a unique opportunity to determine the pathoanatomical aspects of visual hallucinations. During a 3-year period, 41 consecutive patients who acquired visual field defects after neurosurgery were examined for the occurrence of visual hallucination. Postoperatively, four of these patients experienced visual hallucinations. In two of them an upper quadrantanopia developed after the patients had undergone selective amygdalohippocampectomy. In the other two patients a complete hemianopia developed, in one case after resection of a parietal astrocytoma and in the other after resection of an occipital glioblastoma multiforme. The visual hallucinations were transient and gradually disappeared between 4 days and 6 months postoperatively. The patients were aware of the fact that their hallucinations were fictitious and displayed no psychosis. Electroencephalographic recordings were obtained in only two patients and epileptic discharges were found.

Deafferentiation of cortical association areas may lead to the spontaneous generation of complex visual phenomena. In the present series this phenomenon occurred in approximately 10% of patients with postoperative visual field defects. In all four cases the central optic radiation was damaged between the lateral geniculate nucleus and the primary visual cortex. The complex nature of the visual hallucination indicates that they were generated in visual association areas.

Pediatric phantom vision (Charles Bonnet) syndrome

Visual symptomatology in childhood often presents diagnostic difficulties. Recurrent paroxysmal visual complaints, although typically associated with migraine, may also signal other disorders. We describe a 9-year-old partially sighted male with paroxysmal zoopsias resulting from Charles Bonnet syndrome. This condition is characterized by paroxysmal visual hallucinations occurring in patients with chronic visual impairment, akin to the phantom-limb phenomenon. This pediatric case is the fourth report of this condition. We have reviewed the other cases.

Charles Bonnet syndrome in glaucoma patients with low vision

PURPOSE

To characterize the nature and frequency of Charles Bonnet syndrome in glaucoma patients with low vision.

PATIENTS AND METHODS

All patients attending the glaucoma clinic during a period of 10 months who had visual acuity of 20/80 or less in both eyes were included in this study. Each patient was questioned about the occurrence of visual hallucinations. Those who responded positively had a thorough interview relating to the characteristics of the hallucinations. Medical history and social history were taken, followed by a complete ocular examination.

RESULTS

Eighty-nine patients met the inclusion criteria. Eleven patients (12.3%), eight men and three women, admitted to having experienced visual hallucinations. Except for one case, the patients did not disclose this experience previously. Eight patients had one repeatable hallucination, and three patients experienced more than one sight. The visions were usually sharp, and the figures were occasionally incomplete. Most hallucinations were chromatic. Frequency of hallucinations varied between daily and weekly, and duration was mostly a few minutes. In addition to glaucoma, nine of the eleven patients had other ocular findings that could have contributed to the reduction of vision.

CONCLUSION

Visual hallucinations are not rare in glaucoma patients with low vision. Patients tend to conceal their experience of visual hallucinations, but a discussion of these phenomena with the patient and assurance of their harmless nature will reduce his or her anxiety and concerns.

Atypical Charles Bonnet hallucinations: an elf in the woodshed, a spirit of evil, and the cowboy malefactors

In this article, the authors review the literature on the Charles Bonnet syndrome (CBS), a condition involving visual hallucinations in normal persons with severe sight loss. Attempts to assess the characteristics of this "phantom vision" have resulted in descriptions of a "typical" CBS hallucination. However, the many exceptions to a modal CBS experience cause the authors to postulate two other general categories of CBS hallucinations: a) the atypical sensory/perceptual (ASP), and b) the atypical psychodynamic (APD) hallucinations. Case studies illustrating these two types are provided. Extending the categories of Charles Bonnet hallucinations allows for more specific diagnosis, treatment, and may result in the possibility of greater precision in future research.

Social and psychological characteristics of elderly visually handicapped patients with the Charles Bonnet Syndrome

The Charles Bonnet syndrome (CBS) is characterized by the presence of complex visual hallucinations in psychologically normal people. The syndrome occurs predominantly in the visually handicapped elderly. Little is known about its etiology and pathogenesis. The aim of this study was to examine the associations of CBS with psychological and social determinants. All subjects were patients older than 64 years from a low-vision unit. Using a case-control approach, 50 patients with CBS and 80 patients without visual hallucinations were interviewed about their educational level, social circumstances, number of social contacts, and ability to cope with visual handicap. Loneliness was measured with the De Jong-Gierveld-Kamphuis loneliness scale, and personality traits were examined with the Dutch-language short version of the Minnesota Multiphasic Personality Inventory ([MMPI] Nederlandse Verkorte MMPI [NVM]). Compared with the control group, significantly more CBS patients were lonely. Mean scores on the NVM shyness scale and extraversion scale were significantly higher and lower, respectively, in CBS patients. In multiple logistic regression analysis for the three determinants simultaneously, loneliness and low extraversion were significant predictors for CBS, but shyness was not. It is concluded that loneliness, low extraversion, and shyness are risk indicators for CBS in elderly visually handicapped people. The findings suggest that CBS is associated with a low quality of social contacts.

Non-painful sensory phenomena after spinal cord injury

OBJECTIVES

Non-painful sensory phenomena or "phantom" sensations are common after spinal cord injury. However, the physiological mechanisms responsible for these sensations are poorly understood. The aim of this study, therefore, was to document in a prospective fashion the time course, prevalence, and features of non-painful sensory phenomena after spinal cord injury, and to determine whether there was a relation between the presence of these sensations and completeness, level of injury, and type of spinal cord injury.

METHODS

Patients admitted to an acute spinal injuries unit were interviewed after admission and at several time points over a 2 year period to determine the presence and characteristics of non-painful sensations. Sensations were divided into simple and complex, with complex referring to sensations that incorporated a sensation of volume, length, posture, or movement.

RESULTS

The present study showed that the large majority (90%) of patients experience either type of sensation and most complex sensations (60%) are first experienced within 24 hours after the injury. Complex sensations were more common in those patients who had complete spinal cord injuries. The presence of either type of sensation did not seem to be related to the level of injury or the type of injury (cord syndrome). A relatively small proportion (22%) of patients reported that the postural sensations were related to their position at the time of injury and sensations were more commonly related to a familiar, comfortable, or often used position before the spinal cord injury.

CONCLUSION

Complex sensations such as postural illusions seem to be due to functional changes in the CNS that may occur almost immediately after spinal cord injury. These sensations may be related to a strong sensory memory "imprint" that has been established before injury.

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.

Therapeutic options in Charles Bonnet syndrome

The term 'Charles Bonnet syndrome' refers to visual pseudohallucinations occurring especially in elderly people with reduced visual acuity. Despite numerous case reports, few successful methods of treatment have been described. Therapies with classical neuroleptics, antidepressants or benzodiazepines have generally been found to be unpromising. Only with carbamazepine treatment has improvement been observed in a few cases. In the three cases reported here, we successfully treated the condition with the atypical neuroleptic melperone.

Charles Bonnet syndrome: an early marker for dementia?

OBJECTIVE

To clarify the neuropsychological function in patients with Charles Bonnet Syndrome.

DESIGN

Control group comparison study.

SETTING

University of Chicago Hospitals.

PARTICIPANTS

The neuropsychological function of 15 older adults with presenting complaints of visual hallucinations who met criteria for Charles Bonnet Syndrome (CBS) were compared with 11 demographically matched controls to determine if there was any evidence of functional brain impairment. CBS patients were screened for focal brain lesions and epileptic disturbance via MRI and EEG and also received pattern visual evoked potentials and ophthalmological examinations.

MEASUREMENTS

Scores from the Wechsler Adult Intelligence Scale-Revised, Mattis Dementia Rating Scale, Wechsler Memory Scale, and the Auditory Verbal Learning Test were compared.

RESULTS

Significant differences were found between the two groups on the neuropsychological measures. Moreover, 14 of 14 subjects had ocular abnormalities and six of eight had abnormal age-corrected pattern visual evoked potentials indicative of dysfunction in the visual system.

CONCLUSIONS

The results of the study indicate that patients diagnosed with Charles Bonnet Syndrome evidence neuropsychological changes commonly associated with the early stages of dementia. Therefore, in patients with impaired vision, the appearance of cognitive deficits, albeit subtle, occur with the onset of visual hallucinations. We propose that isolated visual hallucinations in the older adult may be an indication of the early stages of dementia.

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.

The Charles Bonnet syndrome: A description of two cases

The Charles Bonnet syndrome is characterized by the occurrence of visual hallucinations in elderly people, but without any mental disorders. Two clinical cases are described. An etiological and physiopathological theory is proposed, based on vascular pathology, lack of visual stimulation and a psychodynamic component.