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Commentators agree that the Perception and Attention Deficit (PAD) model is a promising model for accounting for recurrent complex visual hallucinations (RCVH) across several disorders, though with varying detailed criticisms. Its central tenets are not modified, but further consideration of generative models of visual processing and the relationship of proto-objects and memory systems allows the PAD model to deal with variations in phenomenology. The commentaries suggest new ways to generate evidence that will test the model.

As many as two million people in the United Kingdom repeatedly see people, animals, and objects that have no objective reality. Hallucinations on the border of sleep, dementing illnesses, delirium, eye disease, and schizophrenia account for 90% of these. The remainder have rarer disorders. We review existing models of recurrent complex visual hallucinations (RCVH) in the awake person, including cortical irritation, cortical hyperexcitability and cortical release, top-down activation, misperception, dream intrusion, and interactive models. We provide evidence that these can neither fully account for the phenomenology of RCVH, nor for variations in the frequency of RCVH in different disorders. We propose a novel Perception and Attention Deficit (PAD) model for RCVH. A combination of impaired attentional binding and poor sensory activation of a correct proto-object, in conjunction with a relatively intact scene representation, bias perception to allow the intrusion of a hallucinatory proto-object into a scene perception. Incorporation of this image into a context-specific hallucinatory scene representation accounts for repetitive hallucinations. We suggest that these impairments are underpinned by disturbances in a lateral frontal cortex-ventral visual stream system. We show how the frequency of RCVH in different diseases is related to the coexistence of attentional and visual perceptual impairments; how attentional and perceptual processes can account for their phenomenology; and that diseases and other states with high rates of RCVH have cholinergic dysfunction in both frontal cortex and the ventral visual stream. Several tests of the model are indicated, together with a number of treatment options that it generates. Keywords: Blindness; Charles Bonnet; cholinergic; cortical release; delirium; dementia; dream intrusion; hallucination; Perception and Attention Deficit (PAD) model; schizophrenia.

Merker's core idea, that the experience of being conscious reflects the interactions of actions, targets, and motivations in the upper brainstem, with cortex providing the content of the conscious experience, merits serious consideration. However, we have two areas of concern: first, that his definition of consciousness is so broad that it is difficult to find any organisms with a brain that could be non-conscious; second, that the focus on one cortical-subcortical system neglects other systems (e.g., basal forebrain and brainstem cholinergic systems and their cortical and thalamic target areas) which may be of at least equal significance.

Applying Behrendt & Young's (B&Y's) model of thalamocortical synchrony to complex visual hallucinations in neurodegenerative disorders, such as dementia with Lewy bodies and progressive supranuclear palsy, leads us to propose that the primary pathology may be cortical rather than thalamic. Additionally, the extinction of active hallucinations by eye closure challenges their conception of the role of reduced sensory input.

There has been limited application of cognitive behavioural therapy (CBT) to the treatment of distressing visual hallucinations (VH) in people with psychosis. Preliminary research applying interventions to a novel presenting issue are enhanced by utilizing designs that allow strong inferences to be made about the effect of the intervention. Hence, this study aimed to measure change in appraisal, affect, and behaviour as a consequence of CBT VH, to improve understanding of the process of change. A multiple-baseline experimental single-case design methodology was used with five participants who received a CBT VH treatment package. Participants used daily diary measures to record appraisals, affect, and behaviours related to the distressing VH. Standardized measures were completed at each phase change. Four individuals completed therapy. Formal visual analysis of the data supported by statistical analysis indicated significant changes for appraisal and affect, with replication across three participants. Changes in frequency of VH were reported in two cases. Change was not evident on the standardized measures. This study replicates and extends the findings in showing potential value of CBT VH. Further research should consider alternative methods of capturing behavioural change. Attempts should also be made to replicate across therapists and centres. [ABSTRACT FROM AUTHOR]

Background: A previous study (Gauntlett-Gilbert and Kuipers, 2005) has suggested that distress associated with complex visual hallucinations (CVHs) in younger adults with psychosis may more strongly relate to appraisals of meaning than to the content of the hallucination. However, visual hallucinations are most commonly seen in the disorders of later life, where this relationship has not been investigated. Aim: To establish if there is a relationship between appraisals of CVHs and distress in older, non-psychotic people with CVHs. Method: All variables were measured using a semi-structured interview and were compared between a high distress group (n = 16) and a low distress group (n = 19). Results: The high distress group rated their hallucinations as more malevolent and omnipotent, with greater negative implications for physical and mental health. There was no significant difference between groups on ratings of hallucination content (independently rated), frequency, awareness or control. Conclusion: Appraisals of CVHs are linked to distress. [ABSTRACT FROM AUTHOR]

Background: Visual hallucinations (VH) are a common experience and can be distressing and disabling, particularly for people suffering from psychotic illness. However, not everyone with visual hallucinations reports the experience to be distressing. Models of VH propose that appraisals of VH as a threat to wellbeing and the use of safety seeking behaviours help maintain the distress. Aims: This study investigated whether people with distressing VH report threat appraisals and use safety behaviours. Method: The study utilized a single group descriptive design, in which 15 participants with psychosis and VH were asked questions in order to assess the content, distress, appraisals, and behaviours associated with visual hallucinations. Results: People who found visual hallucinations distressing (n = 13) held negative appraisals about those hallucinations and specifically saw them as a threat to their physical or psychological wellbeing. They also engaged in safety seeking behaviours that were logically related to the appraisal and served to maintain the distress. Conclusions: People with distressing VH regard them as a threat to their wellbeing and use safety seeking behaviours as a result of this perceived threat. These key processes are potential targets for treatments that will alleviate the distress associated with VH. [ABSTRACT FROM PUBLISHER]

Mental health policy places a requirement on clinicians to address matters of religion and belief, yet practice falls far behind. This paper summarizes a Panel Discussion at the 2008 BABCP Annual Conference attended by over 50 people. The five speakers each presented their experience of working with particular faith groups (Orthodox Jewish, Christian, Muslim) and from an agnostic viewpoint. Common themes are given, as well as practical advice to therapists who find themselves working with people who hold strong faith beliefs they may not share. [ABSTRACT FROM AUTHOR]